text: /*
   * omap_hwmod implementation for OMAP2/3/4
   *
   * Copyright (C) 2009-2011 Nokia Corporation
   * Copyright (C) 2011-2012 Texas Instruments, Inc.
   *
   * Paul Walmsley, Benoît Cousson, Kevin Hilman
   *
   * Created in collaboration with (alphabetical order): Thara Gopinath,
   * Tony Lindgren, Rajendra Nayak, Vikram Pandita, Sakari Poussa, Anand
   * Sawant, Santosh Shilimkar, Richard Woodruff
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   * Introduction
   * ------------
   * One way to view an OMAP SoC is as a collection of largely unrelated
   * IP blocks connected by interconnects.  The IP blocks include
   * devices such as ARM processors, audio serial interfaces, UARTs,
   * etc.  Some of these devices, like the DSP, are created by TI;
   * others, like the SGX, largely originate from external vendors.  In
   * TI's documentation, on-chip devices are referred to as "OMAP
   * modules."  Some of these IP blocks are identical across several
   * OMAP versions.  Others are revised frequently.
   *
   * These OMAP modules are tied together by various interconnects.
   * Most of the address and data flow between modules is via OCP-based
   * interconnects such as the L3 and L4 buses; but there are other
   * interconnects that distribute the hardware clock tree, handle idle
   * and reset signaling, supply power, and connect the modules to
   * various pads or balls on the OMAP package.
   *
   * OMAP hwmod provides a consistent way to describe the on-chip
   * hardware blocks and their integration into the rest of the chip.
   * This description can be automatically generated from the TI
   * hardware database.  OMAP hwmod provides a standard, consistent API
   * to reset, enable, idle, and disable these hardware blocks.  And
   * hwmod provides a way for other core code, such as the Linux device
   * code or the OMAP power management and address space mapping code,
   * to query the hardware database.
   *
   * Using hwmod
   * -----------
   * Drivers won't call hwmod functions directly.  That is done by the
   * omap_device code, and in rare occasions, by custom integration code
   * in arch/arm/ *omap*.  The omap_device code includes functions to
   * build a struct platform_device using omap_hwmod data, and that is
   * currently how hwmod data is communicated to drivers and to the
   * Linux driver model.  Most drivers will call omap_hwmod functions only
   * indirectly, via pm_runtime*() functions.
   *
   * From a layering perspective, here is where the OMAP hwmod code
   * fits into the kernel software stack:
   *
   *            +-------------------------------+
   *            |      Device driver code       |
   *            |      (e.g., drivers/)         |
   *            +-------------------------------+
   *            |      Linux driver model       |
   *            |     (platform_device /        |
   *            |  platform_driver data/code)   |
   *            +-------------------------------+
   *            | OMAP core-driver integration  |
   *            |(arch/arm/mach-omap2/devices.c)|
   *            +-------------------------------+
   *            |      omap_device code         |
   *            | (../plat-omap/omap_device.c)  |
   *            +-------------------------------+
   *   ---->    |    omap_hwmod code/data       |    <-----
   *            | (../mach-omap2/omap_hwmod*)   |
   *            +-------------------------------+
   *            | OMAP clock/PRCM/register fns  |
   *            | (__raw_{read,write}l, clk*)   |
   *            +-------------------------------+
   *
   * Device drivers should not contain any OMAP-specific code or data in
   * them.  They should only contain code to operate the IP block that
   * the driver is responsible for.  This is because these IP blocks can
   * also appear in other SoCs, either from TI (such as DaVinci) or from
   * other manufacturers; and drivers should be reusable across other
   * platforms.
   *
   * The OMAP hwmod code also will attempt to reset and idle all on-chip
   * devices upon boot.  The goal here is for the kernel to be
   * completely self-reliant and independent from bootloaders.  This is
   * to ensure a repeatable configuration, both to ensure consistent
   * runtime behavior, and to make it easier for others to reproduce
   * bugs.
   *
   * OMAP module activity states
   * ---------------------------
   * The hwmod code considers modules to be in one of several activity
   * states.  IP blocks start out in an UNKNOWN state, then once they
   * are registered via the hwmod code, proceed to the REGISTERED state.
   * Once their clock names are resolved to clock pointers, the module
   * enters the CLKS_INITED state; and finally, once the module has been
   * reset and the integration registers programmed, the INITIALIZED state
   * is entered.  The hwmod code will then place the module into either
   * the IDLE state to save power, or in the case of a critical system
   * module, the ENABLED state.
   *
   * OMAP core integration code can then call omap_hwmod*() functions
   * directly to move the module between the IDLE, ENABLED, and DISABLED
   * states, as needed.  This is done during both the PM idle loop, and
   * in the OMAP core integration code's implementation of the PM runtime
   * functions.
   *
   * References
   * ----------
   * This is a partial list.
   * - OMAP2420 Multimedia Processor Silicon Revision 2.1.1, 2.2 (SWPU064)
   * - OMAP2430 Multimedia Device POP Silicon Revision 2.1 (SWPU090)
   * - OMAP34xx Multimedia Device Silicon Revision 3.1 (SWPU108)
   * - OMAP4430 Multimedia Device Silicon Revision 1.0 (SWPU140)
   * - Open Core Protocol Specification 2.2
   *
   * To do:
   * - handle IO mapping
   * - bus throughput & module latency measurement code
   *
   * XXX add tests at the beginning of each function to ensure the hwmod is
   * in the appropriate state
   * XXX error return values should be checked to ensure that they are
   * appropriate
   */
  #undef DEBUG
  
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/io.h>
  #include <linux/clk-provider.h>
  #include <linux/delay.h>
  #include <linux/err.h>
  #include <linux/list.h>
  #include <linux/mutex.h>
  #include <linux/spinlock.h>
  #include <linux/slab.h>
  #include <linux/bootmem.h>
  #include <linux/cpu.h>
  #include <linux/of.h>
  #include <linux/of_address.h>
  
  #include <asm/system_misc.h>
  
  #include "clock.h"
  #include "omap_hwmod.h"
  
  #include "soc.h"
  #include "common.h"
  #include "clockdomain.h"
  #include "powerdomain.h"
  #include "cm2xxx.h"
  #include "cm3xxx.h"
  #include "cminst44xx.h"
  #include "cm33xx.h"
  #include "prm.h"
  #include "prm3xxx.h"
  #include "prm44xx.h"
  #include "prm33xx.h"
  #include "prminst44xx.h"
  #include "mux.h"
  #include "pm.h"
  
  /* Name of the OMAP hwmod for the MPU */
  #define MPU_INITIATOR_NAME		"mpu"
  
  /*
   * Number of struct omap_hwmod_link records per struct
   * omap_hwmod_ocp_if record (master->slave and slave->master)
   */
  #define LINKS_PER_OCP_IF		2
  
  /**
   * struct omap_hwmod_soc_ops - fn ptrs for some SoC-specific operations
   * @enable_module: function to enable a module (via MODULEMODE)
   * @disable_module: function to disable a module (via MODULEMODE)
   *
   * XXX Eventually this functionality will be hidden inside the PRM/CM
   * device drivers.  Until then, this should avoid huge blocks of cpu_is_*()
   * conditionals in this code.
   */
  struct omap_hwmod_soc_ops {
  	void (*enable_module)(struct omap_hwmod *oh);
  	int (*disable_module)(struct omap_hwmod *oh);
  	int (*wait_target_ready)(struct omap_hwmod *oh);
  	int (*assert_hardreset)(struct omap_hwmod *oh,
  				struct omap_hwmod_rst_info *ohri);
  	int (*deassert_hardreset)(struct omap_hwmod *oh,
  				  struct omap_hwmod_rst_info *ohri);
  	int (*is_hardreset_asserted)(struct omap_hwmod *oh,
  				     struct omap_hwmod_rst_info *ohri);
  	int (*init_clkdm)(struct omap_hwmod *oh);
  	void (*update_context_lost)(struct omap_hwmod *oh);
  	int (*get_context_lost)(struct omap_hwmod *oh);
  };
  
  /* soc_ops: adapts the omap_hwmod code to the currently-booted SoC */
  static struct omap_hwmod_soc_ops soc_ops;
  
  /* omap_hwmod_list contains all registered struct omap_hwmods */
  static LIST_HEAD(omap_hwmod_list);
  
  /* mpu_oh: used to add/remove MPU initiator from sleepdep list */
  static struct omap_hwmod *mpu_oh;
  
  /* io_chain_lock: used to serialize reconfigurations of the I/O chain */
  static DEFINE_SPINLOCK(io_chain_lock);
  
  /*
   * linkspace: ptr to a buffer that struct omap_hwmod_link records are
   * allocated from - used to reduce the number of small memory
   * allocations, which has a significant impact on performance
   */
  static struct omap_hwmod_link *linkspace;
  
  /*
   * free_ls, max_ls: array indexes into linkspace; representing the
   * next free struct omap_hwmod_link index, and the maximum number of
   * struct omap_hwmod_link records allocated (respectively)
   */
  static unsigned short free_ls, max_ls, ls_supp;
  
  /* inited: set to true once the hwmod code is initialized */
  static bool inited;
  
  /* Private functions */
  
  /**
   * _fetch_next_ocp_if - return the next OCP interface in a list
   * @p: ptr to a ptr to the list_head inside the ocp_if to return
   * @i: pointer to the index of the element pointed to by @p in the list
   *
   * Return a pointer to the struct omap_hwmod_ocp_if record
   * containing the struct list_head pointed to by @p, and increment
   * @p such that a future call to this routine will return the next
   * record.
   */
  static struct omap_hwmod_ocp_if *_fetch_next_ocp_if(struct list_head **p,
  						    int *i)
  {
  	struct omap_hwmod_ocp_if *oi;
  
  	oi = list_entry(*p, struct omap_hwmod_link, node)->ocp_if;
  	*p = (*p)->next;
  
  	*i = *i + 1;
  
  	return oi;
  }
  
  /**
   * _update_sysc_cache - return the module OCP_SYSCONFIG register, keep copy
   * @oh: struct omap_hwmod *
   *
   * Load the current value of the hwmod OCP_SYSCONFIG register into the
   * struct omap_hwmod for later use.  Returns -EINVAL if the hwmod has no
   * OCP_SYSCONFIG register or 0 upon success.
   */
  static int _update_sysc_cache(struct omap_hwmod *oh)
  {
  	if (!oh->class->sysc) {
  		WARN(1, "omap_hwmod: %s: cannot read OCP_SYSCONFIG: not defined on hwmod's class\n", oh->name);
  		return -EINVAL;
  	}
  
  	/* XXX ensure module interface clock is up */
  
  	oh->_sysc_cache = omap_hwmod_read(oh, oh->class->sysc->sysc_offs);
  
  	if (!(oh->class->sysc->sysc_flags & SYSC_NO_CACHE))
  		oh->_int_flags |= _HWMOD_SYSCONFIG_LOADED;
  
  	return 0;
  }
  
  /**
   * _write_sysconfig - write a value to the module's OCP_SYSCONFIG register
   * @v: OCP_SYSCONFIG value to write
   * @oh: struct omap_hwmod *
   *
   * Write @v into the module class' OCP_SYSCONFIG register, if it has
   * one.  No return value.
   */
  static void _write_sysconfig(u32 v, struct omap_hwmod *oh)
  {
  	if (!oh->class->sysc) {
  		WARN(1, "omap_hwmod: %s: cannot write OCP_SYSCONFIG: not defined on hwmod's class\n", oh->name);
  		return;
  	}
  
  	/* XXX ensure module interface clock is up */
  
  	/* Module might have lost context, always update cache and register */
  	oh->_sysc_cache = v;
  	omap_hwmod_write(v, oh, oh->class->sysc->sysc_offs);
  }
  
  /**
   * _set_master_standbymode: set the OCP_SYSCONFIG MIDLEMODE field in @v
   * @oh: struct omap_hwmod *
   * @standbymode: MIDLEMODE field bits
   * @v: pointer to register contents to modify
   *
   * Update the master standby mode bits in @v to be @standbymode for
   * the @oh hwmod.  Does not write to the hardware.  Returns -EINVAL
   * upon error or 0 upon success.
   */
  static int _set_master_standbymode(struct omap_hwmod *oh, u8 standbymode,
  				   u32 *v)
  {
  	u32 mstandby_mask;
  	u8 mstandby_shift;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_MIDLEMODE))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	mstandby_shift = oh->class->sysc->sysc_fields->midle_shift;
  	mstandby_mask = (0x3 << mstandby_shift);
  
  	*v &= ~mstandby_mask;
  	*v |= __ffs(standbymode) << mstandby_shift;
  
  	return 0;
  }
  
  /**
   * _set_slave_idlemode: set the OCP_SYSCONFIG SIDLEMODE field in @v
   * @oh: struct omap_hwmod *
   * @idlemode: SIDLEMODE field bits
   * @v: pointer to register contents to modify
   *
   * Update the slave idle mode bits in @v to be @idlemode for the @oh
   * hwmod.  Does not write to the hardware.  Returns -EINVAL upon error
   * or 0 upon success.
   */
  static int _set_slave_idlemode(struct omap_hwmod *oh, u8 idlemode, u32 *v)
  {
  	u32 sidle_mask;
  	u8 sidle_shift;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_SIDLEMODE))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	sidle_shift = oh->class->sysc->sysc_fields->sidle_shift;
  	sidle_mask = (0x3 << sidle_shift);
  
  	*v &= ~sidle_mask;
  	*v |= __ffs(idlemode) << sidle_shift;
  
  	return 0;
  }
  
  /**
   * _set_clockactivity: set OCP_SYSCONFIG.CLOCKACTIVITY bits in @v
   * @oh: struct omap_hwmod *
   * @clockact: CLOCKACTIVITY field bits
   * @v: pointer to register contents to modify
   *
   * Update the clockactivity mode bits in @v to be @clockact for the
   * @oh hwmod.  Used for additional powersaving on some modules.  Does
   * not write to the hardware.  Returns -EINVAL upon error or 0 upon
   * success.
   */
  static int _set_clockactivity(struct omap_hwmod *oh, u8 clockact, u32 *v)
  {
  	u32 clkact_mask;
  	u8  clkact_shift;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_CLOCKACTIVITY))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	clkact_shift = oh->class->sysc->sysc_fields->clkact_shift;
  	clkact_mask = (0x3 << clkact_shift);
  
  	*v &= ~clkact_mask;
  	*v |= clockact << clkact_shift;
  
  	return 0;
  }
  
  /**
   * _set_softreset: set OCP_SYSCONFIG.SOFTRESET bit in @v
   * @oh: struct omap_hwmod *
   * @v: pointer to register contents to modify
   *
   * Set the SOFTRESET bit in @v for hwmod @oh.  Returns -EINVAL upon
   * error or 0 upon success.
   */
  static int _set_softreset(struct omap_hwmod *oh, u32 *v)
  {
  	u32 softrst_mask;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_SOFTRESET))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	softrst_mask = (0x1 << oh->class->sysc->sysc_fields->srst_shift);
  
  	*v |= softrst_mask;
  
  	return 0;
  }
  
  /**
   * _clear_softreset: clear OCP_SYSCONFIG.SOFTRESET bit in @v
   * @oh: struct omap_hwmod *
   * @v: pointer to register contents to modify
   *
   * Clear the SOFTRESET bit in @v for hwmod @oh.  Returns -EINVAL upon
   * error or 0 upon success.
   */
  static int _clear_softreset(struct omap_hwmod *oh, u32 *v)
  {
  	u32 softrst_mask;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_SOFTRESET))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1,
  		     "omap_hwmod: %s: sysc_fields absent for sysconfig class\n",
  		     oh->name);
  		return -EINVAL;
  	}
  
  	softrst_mask = (0x1 << oh->class->sysc->sysc_fields->srst_shift);
  
  	*v &= ~softrst_mask;
  
  	return 0;
  }
  
  /**
   * _wait_softreset_complete - wait for an OCP softreset to complete
   * @oh: struct omap_hwmod * to wait on
   *
   * Wait until the IP block represented by @oh reports that its OCP
   * softreset is complete.  This can be triggered by software (see
   * _ocp_softreset()) or by hardware upon returning from off-mode (one
   * example is HSMMC).  Waits for up to MAX_MODULE_SOFTRESET_WAIT
   * microseconds.  Returns the number of microseconds waited.
   */
  static int _wait_softreset_complete(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_class_sysconfig *sysc;
  	u32 softrst_mask;
  	int c = 0;
  
  	sysc = oh->class->sysc;
  
  	if (sysc->sysc_flags & SYSS_HAS_RESET_STATUS)
  		omap_test_timeout((omap_hwmod_read(oh, sysc->syss_offs)
  				   & SYSS_RESETDONE_MASK),
  				  MAX_MODULE_SOFTRESET_WAIT, c);
  	else if (sysc->sysc_flags & SYSC_HAS_RESET_STATUS) {
  		softrst_mask = (0x1 << sysc->sysc_fields->srst_shift);
  		omap_test_timeout(!(omap_hwmod_read(oh, sysc->sysc_offs)
  				    & softrst_mask),
  				  MAX_MODULE_SOFTRESET_WAIT, c);
  	}
  
  	return c;
  }
  
  /**
   * _set_dmadisable: set OCP_SYSCONFIG.DMADISABLE bit in @v
   * @oh: struct omap_hwmod *
   *
   * The DMADISABLE bit is a semi-automatic bit present in sysconfig register
   * of some modules. When the DMA must perform read/write accesses, the
   * DMADISABLE bit is cleared by the hardware. But when the DMA must stop
   * for power management, software must set the DMADISABLE bit back to 1.
   *
   * Set the DMADISABLE bit in @v for hwmod @oh.  Returns -EINVAL upon
   * error or 0 upon success.
   */
  static int _set_dmadisable(struct omap_hwmod *oh)
  {
  	u32 v;
  	u32 dmadisable_mask;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_DMADISABLE))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	/* clocks must be on for this operation */
  	if (oh->_state != _HWMOD_STATE_ENABLED) {
  		pr_warn("omap_hwmod: %s: dma can be disabled only from enabled state\n", oh->name);
  		return -EINVAL;
  	}
  
  	pr_debug("omap_hwmod: %s: setting DMADISABLE\n", oh->name);
  
  	v = oh->_sysc_cache;
  	dmadisable_mask =
  		(0x1 << oh->class->sysc->sysc_fields->dmadisable_shift);
  	v |= dmadisable_mask;
  	_write_sysconfig(v, oh);
  
  	return 0;
  }
  
  /**
   * _set_module_autoidle: set the OCP_SYSCONFIG AUTOIDLE field in @v
   * @oh: struct omap_hwmod *
   * @autoidle: desired AUTOIDLE bitfield value (0 or 1)
   * @v: pointer to register contents to modify
   *
   * Update the module autoidle bit in @v to be @autoidle for the @oh
   * hwmod.  The autoidle bit controls whether the module can gate
   * internal clocks automatically when it isn't doing anything; the
   * exact function of this bit varies on a per-module basis.  This
   * function does not write to the hardware.  Returns -EINVAL upon
   * error or 0 upon success.
   */
  static int _set_module_autoidle(struct omap_hwmod *oh, u8 autoidle,
  				u32 *v)
  {
  	u32 autoidle_mask;
  	u8 autoidle_shift;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_AUTOIDLE))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	autoidle_shift = oh->class->sysc->sysc_fields->autoidle_shift;
  	autoidle_mask = (0x1 << autoidle_shift);
  
  	*v &= ~autoidle_mask;
  	*v |= autoidle << autoidle_shift;
  
  	return 0;
  }
  
  /**
   * _set_idle_ioring_wakeup - enable/disable IO pad wakeup on hwmod idle for mux
   * @oh: struct omap_hwmod *
   * @set_wake: bool value indicating to set (true) or clear (false) wakeup enable
   *
   * Set or clear the I/O pad wakeup flag in the mux entries for the
   * hwmod @oh.  This function changes the @oh->mux->pads_dynamic array
   * in memory.  If the hwmod is currently idled, and the new idle
   * values don't match the previous ones, this function will also
   * update the SCM PADCTRL registers.  Otherwise, if the hwmod is not
   * currently idled, this function won't touch the hardware: the new
   * mux settings are written to the SCM PADCTRL registers when the
   * hwmod is idled.  No return value.
   */
  static void _set_idle_ioring_wakeup(struct omap_hwmod *oh, bool set_wake)
  {
  	struct omap_device_pad *pad;
  	bool change = false;
  	u16 prev_idle;
  	int j;
  
  	if (!oh->mux || !oh->mux->enabled)
  		return;
  
  	for (j = 0; j < oh->mux->nr_pads_dynamic; j++) {
  		pad = oh->mux->pads_dynamic[j];
  
  		if (!(pad->flags & OMAP_DEVICE_PAD_WAKEUP))
  			continue;
  
  		prev_idle = pad->idle;
  
  		if (set_wake)
  			pad->idle |= OMAP_WAKEUP_EN;
  		else
  			pad->idle &= ~OMAP_WAKEUP_EN;
  
  		if (prev_idle != pad->idle)
  			change = true;
  	}
  
  	if (change && oh->_state == _HWMOD_STATE_IDLE)
  		omap_hwmod_mux(oh->mux, _HWMOD_STATE_IDLE);
  }
  
  /**
   * _enable_wakeup: set OCP_SYSCONFIG.ENAWAKEUP bit in the hardware
   * @oh: struct omap_hwmod *
   *
   * Allow the hardware module @oh to send wakeups.  Returns -EINVAL
   * upon error or 0 upon success.
   */
  static int _enable_wakeup(struct omap_hwmod *oh, u32 *v)
  {
  	if (!oh->class->sysc ||
  	    !((oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP) ||
  	      (oh->class->sysc->idlemodes & SIDLE_SMART_WKUP) ||
  	      (oh->class->sysc->idlemodes & MSTANDBY_SMART_WKUP)))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	if (oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP)
  		*v |= 0x1 << oh->class->sysc->sysc_fields->enwkup_shift;
  
  	if (oh->class->sysc->idlemodes & SIDLE_SMART_WKUP)
  		_set_slave_idlemode(oh, HWMOD_IDLEMODE_SMART_WKUP, v);
  	if (oh->class->sysc->idlemodes & MSTANDBY_SMART_WKUP)
  		_set_master_standbymode(oh, HWMOD_IDLEMODE_SMART_WKUP, v);
  
  	/* XXX test pwrdm_get_wken for this hwmod's subsystem */
  
  	return 0;
  }
  
  /**
   * _disable_wakeup: clear OCP_SYSCONFIG.ENAWAKEUP bit in the hardware
   * @oh: struct omap_hwmod *
   *
   * Prevent the hardware module @oh to send wakeups.  Returns -EINVAL
   * upon error or 0 upon success.
   */
  static int _disable_wakeup(struct omap_hwmod *oh, u32 *v)
  {
  	if (!oh->class->sysc ||
  	    !((oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP) ||
  	      (oh->class->sysc->idlemodes & SIDLE_SMART_WKUP) ||
  	      (oh->class->sysc->idlemodes & MSTANDBY_SMART_WKUP)))
  		return -EINVAL;
  
  	if (!oh->class->sysc->sysc_fields) {
  		WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
  		return -EINVAL;
  	}
  
  	if (oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP)
  		*v &= ~(0x1 << oh->class->sysc->sysc_fields->enwkup_shift);
  
  	if (oh->class->sysc->idlemodes & SIDLE_SMART_WKUP)
  		_set_slave_idlemode(oh, HWMOD_IDLEMODE_SMART, v);
  	if (oh->class->sysc->idlemodes & MSTANDBY_SMART_WKUP)
  		_set_master_standbymode(oh, HWMOD_IDLEMODE_SMART, v);
  
  	/* XXX test pwrdm_get_wken for this hwmod's subsystem */
  
  	return 0;
  }
  
  static struct clockdomain *_get_clkdm(struct omap_hwmod *oh)
  {
  	struct clk_hw_omap *clk;
  
  	if (oh->clkdm) {
  		return oh->clkdm;
  	} else if (oh->_clk) {
  		clk = to_clk_hw_omap(__clk_get_hw(oh->_clk));
  		return  clk->clkdm;
  	}
  	return NULL;
  }
  
  /**
   * _add_initiator_dep: prevent @oh from smart-idling while @init_oh is active
   * @oh: struct omap_hwmod *
   *
   * Prevent the hardware module @oh from entering idle while the
   * hardare module initiator @init_oh is active.  Useful when a module
   * will be accessed by a particular initiator (e.g., if a module will
   * be accessed by the IVA, there should be a sleepdep between the IVA
   * initiator and the module).  Only applies to modules in smart-idle
   * mode.  If the clockdomain is marked as not needing autodeps, return
   * 0 without doing anything.  Otherwise, returns -EINVAL upon error or
   * passes along clkdm_add_sleepdep() value upon success.
   */
  static int _add_initiator_dep(struct omap_hwmod *oh, struct omap_hwmod *init_oh)
  {
  	struct clockdomain *clkdm, *init_clkdm;
  
  	clkdm = _get_clkdm(oh);
  	init_clkdm = _get_clkdm(init_oh);
  
  	if (!clkdm || !init_clkdm)
  		return -EINVAL;
  
  	if (clkdm && clkdm->flags & CLKDM_NO_AUTODEPS)
  		return 0;
  
  	return clkdm_add_sleepdep(clkdm, init_clkdm);
  }
  
  /**
   * _del_initiator_dep: allow @oh to smart-idle even if @init_oh is active
   * @oh: struct omap_hwmod *
   *
   * Allow the hardware module @oh to enter idle while the hardare
   * module initiator @init_oh is active.  Useful when a module will not
   * be accessed by a particular initiator (e.g., if a module will not
   * be accessed by the IVA, there should be no sleepdep between the IVA
   * initiator and the module).  Only applies to modules in smart-idle
   * mode.  If the clockdomain is marked as not needing autodeps, return
   * 0 without doing anything.  Returns -EINVAL upon error or passes
   * along clkdm_del_sleepdep() value upon success.
   */
  static int _del_initiator_dep(struct omap_hwmod *oh, struct omap_hwmod *init_oh)
  {
  	struct clockdomain *clkdm, *init_clkdm;
  
  	clkdm = _get_clkdm(oh);
  	init_clkdm = _get_clkdm(init_oh);
  
  	if (!clkdm || !init_clkdm)
  		return -EINVAL;
  
  	if (clkdm && clkdm->flags & CLKDM_NO_AUTODEPS)
  		return 0;
  
  	return clkdm_del_sleepdep(clkdm, init_clkdm);
  }
  
  /**
   * _init_main_clk - get a struct clk * for the the hwmod's main functional clk
   * @oh: struct omap_hwmod *
   *
   * Called from _init_clocks().  Populates the @oh _clk (main
   * functional clock pointer) if a main_clk is present.  Returns 0 on
   * success or -EINVAL on error.
   */
  static int _init_main_clk(struct omap_hwmod *oh)
  {
  	int ret = 0;
  
  	if (!oh->main_clk)
  		return 0;
  
  	oh->_clk = clk_get(NULL, oh->main_clk);
  	if (IS_ERR(oh->_clk)) {
  		pr_warning("omap_hwmod: %s: cannot clk_get main_clk %s\n",
  			   oh->name, oh->main_clk);
  		return -EINVAL;
  	}
  	/*
  	 * HACK: This needs a re-visit once clk_prepare() is implemented
  	 * to do something meaningful. Today its just a no-op.
  	 * If clk_prepare() is used at some point to do things like
  	 * voltage scaling etc, then this would have to be moved to
  	 * some point where subsystems like i2c and pmic become
  	 * available.
  	 */
  	clk_prepare(oh->_clk);
  
  	if (!_get_clkdm(oh))
  		pr_debug("omap_hwmod: %s: missing clockdomain for %s.\n",
  			   oh->name, oh->main_clk);
  
  	return ret;
  }
  
  /**
   * _init_interface_clks - get a struct clk * for the the hwmod's interface clks
   * @oh: struct omap_hwmod *
   *
   * Called from _init_clocks().  Populates the @oh OCP slave interface
   * clock pointers.  Returns 0 on success or -EINVAL on error.
   */
  static int _init_interface_clks(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_ocp_if *os;
  	struct list_head *p;
  	struct clk *c;
  	int i = 0;
  	int ret = 0;
  
  	p = oh->slave_ports.next;
  
  	while (i < oh->slaves_cnt) {
  		os = _fetch_next_ocp_if(&p, &i);
  		if (!os->clk)
  			continue;
  
  		c = clk_get(NULL, os->clk);
  		if (IS_ERR(c)) {
  			pr_warning("omap_hwmod: %s: cannot clk_get interface_clk %s\n",
  				   oh->name, os->clk);
  			ret = -EINVAL;
  		}
  		os->_clk = c;
  		/*
  		 * HACK: This needs a re-visit once clk_prepare() is implemented
  		 * to do something meaningful. Today its just a no-op.
  		 * If clk_prepare() is used at some point to do things like
  		 * voltage scaling etc, then this would have to be moved to
  		 * some point where subsystems like i2c and pmic become
  		 * available.
  		 */
  		clk_prepare(os->_clk);
  	}
  
  	return ret;
  }
  
  /**
   * _init_opt_clk - get a struct clk * for the the hwmod's optional clocks
   * @oh: struct omap_hwmod *
   *
   * Called from _init_clocks().  Populates the @oh omap_hwmod_opt_clk
   * clock pointers.  Returns 0 on success or -EINVAL on error.
   */
  static int _init_opt_clks(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_opt_clk *oc;
  	struct clk *c;
  	int i;
  	int ret = 0;
  
  	for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++) {
  		c = clk_get(NULL, oc->clk);
  		if (IS_ERR(c)) {
  			pr_warning("omap_hwmod: %s: cannot clk_get opt_clk %s\n",
  				   oh->name, oc->clk);
  			ret = -EINVAL;
  		}
  		oc->_clk = c;
  		/*
  		 * HACK: This needs a re-visit once clk_prepare() is implemented
  		 * to do something meaningful. Today its just a no-op.
  		 * If clk_prepare() is used at some point to do things like
  		 * voltage scaling etc, then this would have to be moved to
  		 * some point where subsystems like i2c and pmic become
  		 * available.
  		 */
  		clk_prepare(oc->_clk);
  	}
  
  	return ret;
  }
  
  /**
   * _enable_clocks - enable hwmod main clock and interface clocks
   * @oh: struct omap_hwmod *
   *
   * Enables all clocks necessary for register reads and writes to succeed
   * on the hwmod @oh.  Returns 0.
   */
  static int _enable_clocks(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_ocp_if *os;
  	struct list_head *p;
  	int i = 0;
  
  	pr_debug("omap_hwmod: %s: enabling clocks\n", oh->name);
  
  	if (oh->_clk)
  		clk_enable(oh->_clk);
  
  	p = oh->slave_ports.next;
  
  	while (i < oh->slaves_cnt) {
  		os = _fetch_next_ocp_if(&p, &i);
  
  		if (os->_clk && (os->flags & OCPIF_SWSUP_IDLE))
  			clk_enable(os->_clk);
  	}
  
  	/* The opt clocks are controlled by the device driver. */
  
  	return 0;
  }
  
  /**
   * _disable_clocks - disable hwmod main clock and interface clocks
   * @oh: struct omap_hwmod *
   *
   * Disables the hwmod @oh main functional and interface clocks.  Returns 0.
   */
  static int _disable_clocks(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_ocp_if *os;
  	struct list_head *p;
  	int i = 0;
  
  	pr_debug("omap_hwmod: %s: disabling clocks\n", oh->name);
  
  	if (oh->_clk)
  		clk_disable(oh->_clk);
  
  	p = oh->slave_ports.next;
  
  	while (i < oh->slaves_cnt) {
  		os = _fetch_next_ocp_if(&p, &i);
  
  		if (os->_clk && (os->flags & OCPIF_SWSUP_IDLE))
  			clk_disable(os->_clk);
  	}
  
  	/* The opt clocks are controlled by the device driver. */
  
  	return 0;
  }
  
  static void _enable_optional_clocks(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_opt_clk *oc;
  	int i;
  
  	pr_debug("omap_hwmod: %s: enabling optional clocks\n", oh->name);
  
  	for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++)
  		if (oc->_clk) {
  			pr_debug("omap_hwmod: enable %s:%s\n", oc->role,
  				 __clk_get_name(oc->_clk));
  			clk_enable(oc->_clk);
  		}
  }
  
  static void _disable_optional_clocks(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_opt_clk *oc;
  	int i;
  
  	pr_debug("omap_hwmod: %s: disabling optional clocks\n", oh->name);
  
  	for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++)
  		if (oc->_clk) {
  			pr_debug("omap_hwmod: disable %s:%s\n", oc->role,
  				 __clk_get_name(oc->_clk));
  			clk_disable(oc->_clk);
  		}
  }
  
  /**
   * _omap4_enable_module - enable CLKCTRL modulemode on OMAP4
   * @oh: struct omap_hwmod *
   *
   * Enables the PRCM module mode related to the hwmod @oh.
   * No return value.
   */
  static void _omap4_enable_module(struct omap_hwmod *oh)
  {
  	if (!oh->clkdm || !oh->prcm.omap4.modulemode)
  		return;
  
  	pr_debug("omap_hwmod: %s: %s: %d\n",
  		 oh->name, __func__, oh->prcm.omap4.modulemode);
  
  	omap4_cminst_module_enable(oh->prcm.omap4.modulemode,
  				   oh->clkdm->prcm_partition,
  				   oh->clkdm->cm_inst,
  				   oh->clkdm->clkdm_offs,
  				   oh->prcm.omap4.clkctrl_offs);
  }
  
  /**
   * _am33xx_enable_module - enable CLKCTRL modulemode on AM33XX
   * @oh: struct omap_hwmod *
   *
   * Enables the PRCM module mode related to the hwmod @oh.
   * No return value.
   */
  static void _am33xx_enable_module(struct omap_hwmod *oh)
  {
  	if (!oh->clkdm || !oh->prcm.omap4.modulemode)
  		return;
  
  	pr_debug("omap_hwmod: %s: %s: %d\n",
  		 oh->name, __func__, oh->prcm.omap4.modulemode);
  
  	am33xx_cm_module_enable(oh->prcm.omap4.modulemode, oh->clkdm->cm_inst,
  				oh->clkdm->clkdm_offs,
  				oh->prcm.omap4.clkctrl_offs);
  }
  
  /**
   * _omap4_wait_target_disable - wait for a module to be disabled on OMAP4
   * @oh: struct omap_hwmod *
   *
   * Wait for a module @oh to enter slave idle.  Returns 0 if the module
   * does not have an IDLEST bit or if the module successfully enters
   * slave idle; otherwise, pass along the return value of the
   * appropriate *_cm*_wait_module_idle() function.
   */
  static int _omap4_wait_target_disable(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return -EINVAL;
  
  	if (oh->_int_flags & _HWMOD_NO_MPU_PORT || !oh->clkdm)
  		return 0;
  
  	if (oh->flags & HWMOD_NO_IDLEST)
  		return 0;
  
  	return omap4_cminst_wait_module_idle(oh->clkdm->prcm_partition,
  					     oh->clkdm->cm_inst,
  					     oh->clkdm->clkdm_offs,
  					     oh->prcm.omap4.clkctrl_offs);
  }
  
  /**
   * _am33xx_wait_target_disable - wait for a module to be disabled on AM33XX
   * @oh: struct omap_hwmod *
   *
   * Wait for a module @oh to enter slave idle.  Returns 0 if the module
   * does not have an IDLEST bit or if the module successfully enters
   * slave idle; otherwise, pass along the return value of the
   * appropriate *_cm*_wait_module_idle() function.
   */
  static int _am33xx_wait_target_disable(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return -EINVAL;
  
  	if (oh->_int_flags & _HWMOD_NO_MPU_PORT)
  		return 0;
  
  	if (oh->flags & HWMOD_NO_IDLEST)
  		return 0;
  
  	return am33xx_cm_wait_module_idle(oh->clkdm->cm_inst,
  					     oh->clkdm->clkdm_offs,
  					     oh->prcm.omap4.clkctrl_offs);
  }
  
  /**
   * _count_mpu_irqs - count the number of MPU IRQ lines associated with @oh
   * @oh: struct omap_hwmod *oh
   *
   * Count and return the number of MPU IRQs associated with the hwmod
   * @oh.  Used to allocate struct resource data.  Returns 0 if @oh is
   * NULL.
   */
  static int _count_mpu_irqs(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_irq_info *ohii;
  	int i = 0;
  
  	if (!oh || !oh->mpu_irqs)
  		return 0;
  
  	do {
  		ohii = &oh->mpu_irqs[i++];
  	} while (ohii->irq != -1);
  
  	return i-1;
  }
  
  /**
   * _count_sdma_reqs - count the number of SDMA request lines associated with @oh
   * @oh: struct omap_hwmod *oh
   *
   * Count and return the number of SDMA request lines associated with
   * the hwmod @oh.  Used to allocate struct resource data.  Returns 0
   * if @oh is NULL.
   */
  static int _count_sdma_reqs(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_dma_info *ohdi;
  	int i = 0;
  
  	if (!oh || !oh->sdma_reqs)
  		return 0;
  
  	do {
  		ohdi = &oh->sdma_reqs[i++];
  	} while (ohdi->dma_req != -1);
  
  	return i-1;
  }
  
  /**
   * _count_ocp_if_addr_spaces - count the number of address space entries for @oh
   * @oh: struct omap_hwmod *oh
   *
   * Count and return the number of address space ranges associated with
   * the hwmod @oh.  Used to allocate struct resource data.  Returns 0
   * if @oh is NULL.
   */
  static int _count_ocp_if_addr_spaces(struct omap_hwmod_ocp_if *os)
  {
  	struct omap_hwmod_addr_space *mem;
  	int i = 0;
  
  	if (!os || !os->addr)
  		return 0;
  
  	do {
  		mem = &os->addr[i++];
  	} while (mem->pa_start != mem->pa_end);
  
  	return i-1;
  }
  
  /**
   * _get_mpu_irq_by_name - fetch MPU interrupt line number by name
   * @oh: struct omap_hwmod * to operate on
   * @name: pointer to the name of the MPU interrupt number to fetch (optional)
   * @irq: pointer to an unsigned int to store the MPU IRQ number to
   *
   * Retrieve a MPU hardware IRQ line number named by @name associated
   * with the IP block pointed to by @oh.  The IRQ number will be filled
   * into the address pointed to by @dma.  When @name is non-null, the
   * IRQ line number associated with the named entry will be returned.
   * If @name is null, the first matching entry will be returned.  Data
   * order is not meaningful in hwmod data, so callers are strongly
   * encouraged to use a non-null @name whenever possible to avoid
   * unpredictable effects if hwmod data is later added that causes data
   * ordering to change.  Returns 0 upon success or a negative error
   * code upon error.
   */
  static int _get_mpu_irq_by_name(struct omap_hwmod *oh, const char *name,
  				unsigned int *irq)
  {
  	int i;
  	bool found = false;
  
  	if (!oh->mpu_irqs)
  		return -ENOENT;
  
  	i = 0;
  	while (oh->mpu_irqs[i].irq != -1) {
  		if (name == oh->mpu_irqs[i].name ||
  		    !strcmp(name, oh->mpu_irqs[i].name)) {
  			found = true;
  			break;
  		}
  		i++;
  	}
  
  	if (!found)
  		return -ENOENT;
  
  	*irq = oh->mpu_irqs[i].irq;
  
  	return 0;
  }
  
  /**
   * _get_sdma_req_by_name - fetch SDMA request line ID by name
   * @oh: struct omap_hwmod * to operate on
   * @name: pointer to the name of the SDMA request line to fetch (optional)
   * @dma: pointer to an unsigned int to store the request line ID to
   *
   * Retrieve an SDMA request line ID named by @name on the IP block
   * pointed to by @oh.  The ID will be filled into the address pointed
   * to by @dma.  When @name is non-null, the request line ID associated
   * with the named entry will be returned.  If @name is null, the first
   * matching entry will be returned.  Data order is not meaningful in
   * hwmod data, so callers are strongly encouraged to use a non-null
   * @name whenever possible to avoid unpredictable effects if hwmod
   * data is later added that causes data ordering to change.  Returns 0
   * upon success or a negative error code upon error.
   */
  static int _get_sdma_req_by_name(struct omap_hwmod *oh, const char *name,
  				 unsigned int *dma)
  {
  	int i;
  	bool found = false;
  
  	if (!oh->sdma_reqs)
  		return -ENOENT;
  
  	i = 0;
  	while (oh->sdma_reqs[i].dma_req != -1) {
  		if (name == oh->sdma_reqs[i].name ||
  		    !strcmp(name, oh->sdma_reqs[i].name)) {
  			found = true;
  			break;
  		}
  		i++;
  	}
  
  	if (!found)
  		return -ENOENT;
  
  	*dma = oh->sdma_reqs[i].dma_req;
  
  	return 0;
  }
  
  /**
   * _get_addr_space_by_name - fetch address space start & end by name
   * @oh: struct omap_hwmod * to operate on
   * @name: pointer to the name of the address space to fetch (optional)
   * @pa_start: pointer to a u32 to store the starting address to
   * @pa_end: pointer to a u32 to store the ending address to
   *
   * Retrieve address space start and end addresses for the IP block
   * pointed to by @oh.  The data will be filled into the addresses
   * pointed to by @pa_start and @pa_end.  When @name is non-null, the
   * address space data associated with the named entry will be
   * returned.  If @name is null, the first matching entry will be
   * returned.  Data order is not meaningful in hwmod data, so callers
   * are strongly encouraged to use a non-null @name whenever possible
   * to avoid unpredictable effects if hwmod data is later added that
   * causes data ordering to change.  Returns 0 upon success or a
   * negative error code upon error.
   */
  static int _get_addr_space_by_name(struct omap_hwmod *oh, const char *name,
  				   u32 *pa_start, u32 *pa_end)
  {
  	int i, j;
  	struct omap_hwmod_ocp_if *os;
  	struct list_head *p = NULL;
  	bool found = false;
  
  	p = oh->slave_ports.next;
  
  	i = 0;
  	while (i < oh->slaves_cnt) {
  		os = _fetch_next_ocp_if(&p, &i);
  
  		if (!os->addr)
  			return -ENOENT;
  
  		j = 0;
  		while (os->addr[j].pa_start != os->addr[j].pa_end) {
  			if (name == os->addr[j].name ||
  			    !strcmp(name, os->addr[j].name)) {
  				found = true;
  				break;
  			}
  			j++;
  		}
  
  		if (found)
  			break;
  	}
  
  	if (!found)
  		return -ENOENT;
  
  	*pa_start = os->addr[j].pa_start;
  	*pa_end = os->addr[j].pa_end;
  
  	return 0;
  }
  
  /**
   * _save_mpu_port_index - find and save the index to @oh's MPU port
   * @oh: struct omap_hwmod *
   *
   * Determines the array index of the OCP slave port that the MPU uses
   * to address the device, and saves it into the struct omap_hwmod.
   * Intended to be called during hwmod registration only. No return
   * value.
   */
  static void __init _save_mpu_port_index(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_ocp_if *os = NULL;
  	struct list_head *p;
  	int i = 0;
  
  	if (!oh)
  		return;
  
  	oh->_int_flags |= _HWMOD_NO_MPU_PORT;
  
  	p = oh->slave_ports.next;
  
  	while (i < oh->slaves_cnt) {
  		os = _fetch_next_ocp_if(&p, &i);
  		if (os->user & OCP_USER_MPU) {
  			oh->_mpu_port = os;
  			oh->_int_flags &= ~_HWMOD_NO_MPU_PORT;
  			break;
  		}
  	}
  
  	return;
  }
  
  /**
   * _find_mpu_rt_port - return omap_hwmod_ocp_if accessible by the MPU
   * @oh: struct omap_hwmod *
   *
   * Given a pointer to a struct omap_hwmod record @oh, return a pointer
   * to the struct omap_hwmod_ocp_if record that is used by the MPU to
   * communicate with the IP block.  This interface need not be directly
   * connected to the MPU (and almost certainly is not), but is directly
   * connected to the IP block represented by @oh.  Returns a pointer
   * to the struct omap_hwmod_ocp_if * upon success, or returns NULL upon
   * error or if there does not appear to be a path from the MPU to this
   * IP block.
   */
  static struct omap_hwmod_ocp_if *_find_mpu_rt_port(struct omap_hwmod *oh)
  {
  	if (!oh || oh->_int_flags & _HWMOD_NO_MPU_PORT || oh->slaves_cnt == 0)
  		return NULL;
  
  	return oh->_mpu_port;
  };
  
  /**
   * _find_mpu_rt_addr_space - return MPU register target address space for @oh
   * @oh: struct omap_hwmod *
   *
   * Returns a pointer to the struct omap_hwmod_addr_space record representing
   * the register target MPU address space; or returns NULL upon error.
   */
  static struct omap_hwmod_addr_space * __init _find_mpu_rt_addr_space(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_ocp_if *os;
  	struct omap_hwmod_addr_space *mem;
  	int found = 0, i = 0;
  
  	os = _find_mpu_rt_port(oh);
  	if (!os || !os->addr)
  		return NULL;
  
  	do {
  		mem = &os->addr[i++];
  		if (mem->flags & ADDR_TYPE_RT)
  			found = 1;
  	} while (!found && mem->pa_start != mem->pa_end);
  
  	return (found) ? mem : NULL;
  }
  
  /**
   * _enable_sysc - try to bring a module out of idle via OCP_SYSCONFIG
   * @oh: struct omap_hwmod *
   *
   * Ensure that the OCP_SYSCONFIG register for the IP block represented
   * by @oh is set to indicate to the PRCM that the IP block is active.
   * Usually this means placing the module into smart-idle mode and
   * smart-standby, but if there is a bug in the automatic idle handling
   * for the IP block, it may need to be placed into the force-idle or
   * no-idle variants of these modes.  No return value.
   */
  static void _enable_sysc(struct omap_hwmod *oh)
  {
  	u8 idlemode, sf;
  	u32 v;
  	bool clkdm_act;
  	struct clockdomain *clkdm;
  
  	if (!oh->class->sysc)
  		return;
  
  	/*
  	 * Wait until reset has completed, this is needed as the IP
  	 * block is reset automatically by hardware in some cases
  	 * (off-mode for example), and the drivers require the
  	 * IP to be ready when they access it
  	 */
  	if (oh->flags & HWMOD_CONTROL_OPT_CLKS_IN_RESET)
  		_enable_optional_clocks(oh);
  	_wait_softreset_complete(oh);
  	if (oh->flags & HWMOD_CONTROL_OPT_CLKS_IN_RESET)
  		_disable_optional_clocks(oh);
  
  	v = oh->_sysc_cache;
  	sf = oh->class->sysc->sysc_flags;
  
  	clkdm = _get_clkdm(oh);
  	if (sf & SYSC_HAS_SIDLEMODE) {
  		if (oh->flags & HWMOD_SWSUP_SIDLE ||
  		    oh->flags & HWMOD_SWSUP_SIDLE_ACT) {
  			idlemode = HWMOD_IDLEMODE_NO;
  		} else {
  			if (sf & SYSC_HAS_ENAWAKEUP)
  				_enable_wakeup(oh, &v);
  			if (oh->class->sysc->idlemodes & SIDLE_SMART_WKUP)
  				idlemode = HWMOD_IDLEMODE_SMART_WKUP;
  			else
  				idlemode = HWMOD_IDLEMODE_SMART;
  		}
  
  		/*
  		 * This is special handling for some IPs like
  		 * 32k sync timer. Force them to idle!
  		 */
  		clkdm_act = (clkdm && clkdm->flags & CLKDM_ACTIVE_WITH_MPU);
  		if (clkdm_act && !(oh->class->sysc->idlemodes &
  				   (SIDLE_SMART | SIDLE_SMART_WKUP)))
  			idlemode = HWMOD_IDLEMODE_FORCE;
  
  		_set_slave_idlemode(oh, idlemode, &v);
  	}
  
  	if (sf & SYSC_HAS_MIDLEMODE) {
  		if (oh->flags & HWMOD_FORCE_MSTANDBY) {
  			idlemode = HWMOD_IDLEMODE_FORCE;
  		} else if (oh->flags & HWMOD_SWSUP_MSTANDBY) {
  			idlemode = HWMOD_IDLEMODE_NO;
  		} else {
  			if (sf & SYSC_HAS_ENAWAKEUP)
  				_enable_wakeup(oh, &v);
  			if (oh->class->sysc->idlemodes & MSTANDBY_SMART_WKUP)
  				idlemode = HWMOD_IDLEMODE_SMART_WKUP;
  			else
  				idlemode = HWMOD_IDLEMODE_SMART;
  		}
  		_set_master_standbymode(oh, idlemode, &v);
  	}
  
  	/*
  	 * XXX The clock framework should handle this, by
  	 * calling into this code.  But this must wait until the
  	 * clock structures are tagged with omap_hwmod entries
  	 */
  	if ((oh->flags & HWMOD_SET_DEFAULT_CLOCKACT) &&
  	    (sf & SYSC_HAS_CLOCKACTIVITY))
  		_set_clockactivity(oh, oh->class->sysc->clockact, &v);
  
  	_write_sysconfig(v, oh);
  
  	/*
  	 * Set the autoidle bit only after setting the smartidle bit
  	 * Setting this will not have any impact on the other modules.
  	 */
  	if (sf & SYSC_HAS_AUTOIDLE) {
  		idlemode = (oh->flags & HWMOD_NO_OCP_AUTOIDLE) ?
  			0 : 1;
  		_set_module_autoidle(oh, idlemode, &v);
  		_write_sysconfig(v, oh);
  	}
  }
  
  /**
   * _idle_sysc - try to put a module into idle via OCP_SYSCONFIG
   * @oh: struct omap_hwmod *
   *
   * If module is marked as SWSUP_SIDLE, force the module into slave
   * idle; otherwise, configure it for smart-idle.  If module is marked
   * as SWSUP_MSUSPEND, force the module into master standby; otherwise,
   * configure it for smart-standby.  No return value.
   */
  static void _idle_sysc(struct omap_hwmod *oh)
  {
  	u8 idlemode, sf;
  	u32 v;
  
  	if (!oh->class->sysc)
  		return;
  
  	v = oh->_sysc_cache;
  	sf = oh->class->sysc->sysc_flags;
  
  	if (sf & SYSC_HAS_SIDLEMODE) {
  		if (oh->flags & HWMOD_SWSUP_SIDLE) {
  			idlemode = HWMOD_IDLEMODE_FORCE;
  		} else {
  			if (sf & SYSC_HAS_ENAWAKEUP)
  				_enable_wakeup(oh, &v);
  			if (oh->class->sysc->idlemodes & SIDLE_SMART_WKUP)
  				idlemode = HWMOD_IDLEMODE_SMART_WKUP;
  			else
  				idlemode = HWMOD_IDLEMODE_SMART;
  		}
  		_set_slave_idlemode(oh, idlemode, &v);
  	}
  
  	if (sf & SYSC_HAS_MIDLEMODE) {
  		if ((oh->flags & HWMOD_SWSUP_MSTANDBY) ||
  		    (oh->flags & HWMOD_FORCE_MSTANDBY)) {
  			idlemode = HWMOD_IDLEMODE_FORCE;
  		} else {
  			if (sf & SYSC_HAS_ENAWAKEUP)
  				_enable_wakeup(oh, &v);
  			if (oh->class->sysc->idlemodes & MSTANDBY_SMART_WKUP)
  				idlemode = HWMOD_IDLEMODE_SMART_WKUP;
  			else
  				idlemode = HWMOD_IDLEMODE_SMART;
  		}
  		_set_master_standbymode(oh, idlemode, &v);
  	}
  
  	_write_sysconfig(v, oh);
  }
  
  /**
   * _shutdown_sysc - force a module into idle via OCP_SYSCONFIG
   * @oh: struct omap_hwmod *
   *
   * Force the module into slave idle and master suspend. No return
   * value.
   */
  static void _shutdown_sysc(struct omap_hwmod *oh)
  {
  	u32 v;
  	u8 sf;
  
  	if (!oh->class->sysc)
  		return;
  
  	v = oh->_sysc_cache;
  	sf = oh->class->sysc->sysc_flags;
  
  	if (sf & SYSC_HAS_SIDLEMODE)
  		_set_slave_idlemode(oh, HWMOD_IDLEMODE_FORCE, &v);
  
  	if (sf & SYSC_HAS_MIDLEMODE)
  		_set_master_standbymode(oh, HWMOD_IDLEMODE_FORCE, &v);
  
  	if (sf & SYSC_HAS_AUTOIDLE)
  		_set_module_autoidle(oh, 1, &v);
  
  	_write_sysconfig(v, oh);
  }
  
  /**
   * _lookup - find an omap_hwmod by name
   * @name: find an omap_hwmod by name
   *
   * Return a pointer to an omap_hwmod by name, or NULL if not found.
   */
  static struct omap_hwmod *_lookup(const char *name)
  {
  	struct omap_hwmod *oh, *temp_oh;
  
  	oh = NULL;
  
  	list_for_each_entry(temp_oh, &omap_hwmod_list, node) {
  		if (!strcmp(name, temp_oh->name)) {
  			oh = temp_oh;
  			break;
  		}
  	}
  
  	return oh;
  }
  
  /**
   * _init_clkdm - look up a clockdomain name, store pointer in omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Convert a clockdomain name stored in a struct omap_hwmod into a
   * clockdomain pointer, and save it into the struct omap_hwmod.
   * Return -EINVAL if the clkdm_name lookup failed.
   */
  static int _init_clkdm(struct omap_hwmod *oh)
  {
  	if (!oh->clkdm_name) {
  		pr_debug("omap_hwmod: %s: missing clockdomain\n", oh->name);
  		return 0;
  	}
  
  	oh->clkdm = clkdm_lookup(oh->clkdm_name);
  	if (!oh->clkdm) {
  		pr_warning("omap_hwmod: %s: could not associate to clkdm %s\n",
  			oh->name, oh->clkdm_name);
  		return -EINVAL;
  	}
  
  	pr_debug("omap_hwmod: %s: associated to clkdm %s\n",
  		oh->name, oh->clkdm_name);
  
  	return 0;
  }
  
  /**
   * _init_clocks - clk_get() all clocks associated with this hwmod. Retrieve as
   * well the clockdomain.
   * @oh: struct omap_hwmod *
   * @data: not used; pass NULL
   *
   * Called by omap_hwmod_setup_*() (after omap2_clk_init()).
   * Resolves all clock names embedded in the hwmod.  Returns 0 on
   * success, or a negative error code on failure.
   */
  static int _init_clocks(struct omap_hwmod *oh, void *data)
  {
  	int ret = 0;
  
  	if (oh->_state != _HWMOD_STATE_REGISTERED)
  		return 0;
  
  	pr_debug("omap_hwmod: %s: looking up clocks\n", oh->name);
  
  	if (soc_ops.init_clkdm)
  		ret |= soc_ops.init_clkdm(oh);
  
  	ret |= _init_main_clk(oh);
  	ret |= _init_interface_clks(oh);
  	ret |= _init_opt_clks(oh);
  
  	if (!ret)
  		oh->_state = _HWMOD_STATE_CLKS_INITED;
  	else
  		pr_warning("omap_hwmod: %s: cannot _init_clocks\n", oh->name);
  
  	return ret;
  }
  
  /**
   * _lookup_hardreset - fill register bit info for this hwmod/reset line
   * @oh: struct omap_hwmod *
   * @name: name of the reset line in the context of this hwmod
   * @ohri: struct omap_hwmod_rst_info * that this function will fill in
   *
   * Return the bit position of the reset line that match the
   * input name. Return -ENOENT if not found.
   */
  static int _lookup_hardreset(struct omap_hwmod *oh, const char *name,
  			     struct omap_hwmod_rst_info *ohri)
  {
  	int i;
  
  	for (i = 0; i < oh->rst_lines_cnt; i++) {
  		const char *rst_line = oh->rst_lines[i].name;
  		if (!strcmp(rst_line, name)) {
  			ohri->rst_shift = oh->rst_lines[i].rst_shift;
  			ohri->st_shift = oh->rst_lines[i].st_shift;
  			pr_debug("omap_hwmod: %s: %s: %s: rst %d st %d\n",
  				 oh->name, __func__, rst_line, ohri->rst_shift,
  				 ohri->st_shift);
  
  			return 0;
  		}
  	}
  
  	return -ENOENT;
  }
  
  /**
   * _assert_hardreset - assert the HW reset line of submodules
   * contained in the hwmod module.
   * @oh: struct omap_hwmod *
   * @name: name of the reset line to lookup and assert
   *
   * Some IP like dsp, ipu or iva contain processor that require an HW
   * reset line to be assert / deassert in order to enable fully the IP.
   * Returns -EINVAL if @oh is null, -ENOSYS if we have no way of
   * asserting the hardreset line on the currently-booted SoC, or passes
   * along the return value from _lookup_hardreset() or the SoC's
   * assert_hardreset code.
   */
  static int _assert_hardreset(struct omap_hwmod *oh, const char *name)
  {
  	struct omap_hwmod_rst_info ohri;
  	int ret = -EINVAL;
  
  	if (!oh)
  		return -EINVAL;
  
  	if (!soc_ops.assert_hardreset)
  		return -ENOSYS;
  
  	ret = _lookup_hardreset(oh, name, &ohri);
  	if (ret < 0)
  		return ret;
  
  	ret = soc_ops.assert_hardreset(oh, &ohri);
  
  	return ret;
  }
  
  /**
   * _deassert_hardreset - deassert the HW reset line of submodules contained
   * in the hwmod module.
   * @oh: struct omap_hwmod *
   * @name: name of the reset line to look up and deassert
   *
   * Some IP like dsp, ipu or iva contain processor that require an HW
   * reset line to be assert / deassert in order to enable fully the IP.
   * Returns -EINVAL if @oh is null, -ENOSYS if we have no way of
   * deasserting the hardreset line on the currently-booted SoC, or passes
   * along the return value from _lookup_hardreset() or the SoC's
   * deassert_hardreset code.
   */
  static int _deassert_hardreset(struct omap_hwmod *oh, const char *name)
  {
  	struct omap_hwmod_rst_info ohri;
  	int ret = -EINVAL;
  	int hwsup = 0;
  
  	if (!oh)
  		return -EINVAL;
  
  	if (!soc_ops.deassert_hardreset)
  		return -ENOSYS;
  
  	ret = _lookup_hardreset(oh, name, &ohri);
  	if (ret < 0)
  		return ret;
  
  	if (oh->clkdm) {
  		/*
  		 * A clockdomain must be in SW_SUP otherwise reset
  		 * might not be completed. The clockdomain can be set
  		 * in HW_AUTO only when the module become ready.
  		 */
  		hwsup = clkdm_in_hwsup(oh->clkdm);
  		ret = clkdm_hwmod_enable(oh->clkdm, oh);
  		if (ret) {
  			WARN(1, "omap_hwmod: %s: could not enable clockdomain %s: %d\n",
  			     oh->name, oh->clkdm->name, ret);
  			return ret;
  		}
  	}
  
  	_enable_clocks(oh);
  	if (soc_ops.enable_module)
  		soc_ops.enable_module(oh);
  
  	ret = soc_ops.deassert_hardreset(oh, &ohri);
  
  	if (soc_ops.disable_module)
  		soc_ops.disable_module(oh);
  	_disable_clocks(oh);
  
  	if (ret == -EBUSY)
  		pr_warning("omap_hwmod: %s: failed to hardreset\n", oh->name);
  
  	if (!ret) {
  		/*
  		 * Set the clockdomain to HW_AUTO, assuming that the
  		 * previous state was HW_AUTO.
  		 */
  		if (oh->clkdm && hwsup)
  			clkdm_allow_idle(oh->clkdm);
  	} else {
  		if (oh->clkdm)
  			clkdm_hwmod_disable(oh->clkdm, oh);
  	}
  
  	return ret;
  }
  
  /**
   * _read_hardreset - read the HW reset line state of submodules
   * contained in the hwmod module
   * @oh: struct omap_hwmod *
   * @name: name of the reset line to look up and read
   *
   * Return the state of the reset line.  Returns -EINVAL if @oh is
   * null, -ENOSYS if we have no way of reading the hardreset line
   * status on the currently-booted SoC, or passes along the return
   * value from _lookup_hardreset() or the SoC's is_hardreset_asserted
   * code.
   */
  static int _read_hardreset(struct omap_hwmod *oh, const char *name)
  {
  	struct omap_hwmod_rst_info ohri;
  	int ret = -EINVAL;
  
  	if (!oh)
  		return -EINVAL;
  
  	if (!soc_ops.is_hardreset_asserted)
  		return -ENOSYS;
  
  	ret = _lookup_hardreset(oh, name, &ohri);
  	if (ret < 0)
  		return ret;
  
  	return soc_ops.is_hardreset_asserted(oh, &ohri);
  }
  
  /**
   * _are_all_hardreset_lines_asserted - return true if the @oh is hard-reset
   * @oh: struct omap_hwmod *
   *
   * If all hardreset lines associated with @oh are asserted, then return true.
   * Otherwise, if part of @oh is out hardreset or if no hardreset lines
   * associated with @oh are asserted, then return false.
   * This function is used to avoid executing some parts of the IP block
   * enable/disable sequence if its hardreset line is set.
   */
  static bool _are_all_hardreset_lines_asserted(struct omap_hwmod *oh)
  {
  	int i, rst_cnt = 0;
  
  	if (oh->rst_lines_cnt == 0)
  		return false;
  
  	for (i = 0; i < oh->rst_lines_cnt; i++)
  		if (_read_hardreset(oh, oh->rst_lines[i].name) > 0)
  			rst_cnt++;
  
  	if (oh->rst_lines_cnt == rst_cnt)
  		return true;
  
  	return false;
  }
  
  /**
   * _are_any_hardreset_lines_asserted - return true if any part of @oh is
   * hard-reset
   * @oh: struct omap_hwmod *
   *
   * If any hardreset lines associated with @oh are asserted, then
   * return true.  Otherwise, if no hardreset lines associated with @oh
   * are asserted, or if @oh has no hardreset lines, then return false.
   * This function is used to avoid executing some parts of the IP block
   * enable/disable sequence if any hardreset line is set.
   */
  static bool _are_any_hardreset_lines_asserted(struct omap_hwmod *oh)
  {
  	int rst_cnt = 0;
  	int i;
  
  	for (i = 0; i < oh->rst_lines_cnt && rst_cnt == 0; i++)
  		if (_read_hardreset(oh, oh->rst_lines[i].name) > 0)
  			rst_cnt++;
  
  	return (rst_cnt) ? true : false;
  }
  
  /**
   * _omap4_disable_module - enable CLKCTRL modulemode on OMAP4
   * @oh: struct omap_hwmod *
   *
   * Disable the PRCM module mode related to the hwmod @oh.
   * Return EINVAL if the modulemode is not supported and 0 in case of success.
   */
  static int _omap4_disable_module(struct omap_hwmod *oh)
  {
  	int v;
  
  	if (!oh->clkdm || !oh->prcm.omap4.modulemode)
  		return -EINVAL;
  
  	/*
  	 * Since integration code might still be doing something, only
  	 * disable if all lines are under hardreset.
  	 */
  	if (_are_any_hardreset_lines_asserted(oh))
  		return 0;
  
  	pr_debug("omap_hwmod: %s: %s\n", oh->name, __func__);
  
  	omap4_cminst_module_disable(oh->clkdm->prcm_partition,
  				    oh->clkdm->cm_inst,
  				    oh->clkdm->clkdm_offs,
  				    oh->prcm.omap4.clkctrl_offs);
  
  	v = _omap4_wait_target_disable(oh);
  	if (v)
  		pr_warn("omap_hwmod: %s: _wait_target_disable failed\n",
  			oh->name);
  
  	return 0;
  }
  
  /**
   * _am33xx_disable_module - enable CLKCTRL modulemode on AM33XX
   * @oh: struct omap_hwmod *
   *
   * Disable the PRCM module mode related to the hwmod @oh.
   * Return EINVAL if the modulemode is not supported and 0 in case of success.
   */
  static int _am33xx_disable_module(struct omap_hwmod *oh)
  {
  	int v;
  
  	if (!oh->clkdm || !oh->prcm.omap4.modulemode)
  		return -EINVAL;
  
  	pr_debug("omap_hwmod: %s: %s\n", oh->name, __func__);
  
  	if (_are_any_hardreset_lines_asserted(oh))
  		return 0;
  
  	am33xx_cm_module_disable(oh->clkdm->cm_inst, oh->clkdm->clkdm_offs,
  				 oh->prcm.omap4.clkctrl_offs);
  
  	v = _am33xx_wait_target_disable(oh);
  	if (v)
  		pr_warn("omap_hwmod: %s: _wait_target_disable failed\n",
  			oh->name);
  
  	return 0;
  }
  
  /**
   * _ocp_softreset - reset an omap_hwmod via the OCP_SYSCONFIG bit
   * @oh: struct omap_hwmod *
   *
   * Resets an omap_hwmod @oh via the OCP_SYSCONFIG bit.  hwmod must be
   * enabled for this to work.  Returns -ENOENT if the hwmod cannot be
   * reset this way, -EINVAL if the hwmod is in the wrong state,
   * -ETIMEDOUT if the module did not reset in time, or 0 upon success.
   *
   * In OMAP3 a specific SYSSTATUS register is used to get the reset status.
   * Starting in OMAP4, some IPs do not have SYSSTATUS registers and instead
   * use the SYSCONFIG softreset bit to provide the status.
   *
   * Note that some IP like McBSP do have reset control but don't have
   * reset status.
   */
  static int _ocp_softreset(struct omap_hwmod *oh)
  {
  	u32 v;
  	int c = 0;
  	int ret = 0;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_SOFTRESET))
  		return -ENOENT;
  
  	/* clocks must be on for this operation */
  	if (oh->_state != _HWMOD_STATE_ENABLED) {
  		pr_warn("omap_hwmod: %s: reset can only be entered from enabled state\n",
  			oh->name);
  		return -EINVAL;
  	}
  
  	/* For some modules, all optionnal clocks need to be enabled as well */
  	if (oh->flags & HWMOD_CONTROL_OPT_CLKS_IN_RESET)
  		_enable_optional_clocks(oh);
  
  	pr_debug("omap_hwmod: %s: resetting via OCP SOFTRESET\n", oh->name);
  
  	v = oh->_sysc_cache;
  	ret = _set_softreset(oh, &v);
  	if (ret)
  		goto dis_opt_clks;
  
  	_write_sysconfig(v, oh);
  	ret = _clear_softreset(oh, &v);
  	if (ret)
  		goto dis_opt_clks;
  
  	_write_sysconfig(v, oh);
  
  	if (oh->class->sysc->srst_udelay)
  		udelay(oh->class->sysc->srst_udelay);
  
  	c = _wait_softreset_complete(oh);
  	if (c == MAX_MODULE_SOFTRESET_WAIT)
  		pr_warning("omap_hwmod: %s: softreset failed (waited %d usec)\n",
  			   oh->name, MAX_MODULE_SOFTRESET_WAIT);
  	else
  		pr_debug("omap_hwmod: %s: softreset in %d usec\n", oh->name, c);
  
  	/*
  	 * XXX add _HWMOD_STATE_WEDGED for modules that don't come back from
  	 * _wait_target_ready() or _reset()
  	 */
  
  	ret = (c == MAX_MODULE_SOFTRESET_WAIT) ? -ETIMEDOUT : 0;
  
  dis_opt_clks:
  	if (oh->flags & HWMOD_CONTROL_OPT_CLKS_IN_RESET)
  		_disable_optional_clocks(oh);
  
  	return ret;
  }
  
  /**
   * _reset - reset an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Resets an omap_hwmod @oh.  If the module has a custom reset
   * function pointer defined, then call it to reset the IP block, and
   * pass along its return value to the caller.  Otherwise, if the IP
   * block has an OCP_SYSCONFIG register with a SOFTRESET bitfield
   * associated with it, call a function to reset the IP block via that
   * method, and pass along the return value to the caller.  Finally, if
   * the IP block has some hardreset lines associated with it, assert
   * all of those, but do _not_ deassert them. (This is because driver
   * authors have expressed an apparent requirement to control the
   * deassertion of the hardreset lines themselves.)
   *
   * The default software reset mechanism for most OMAP IP blocks is
   * triggered via the OCP_SYSCONFIG.SOFTRESET bit.  However, some
   * hwmods cannot be reset via this method.  Some are not targets and
   * therefore have no OCP header registers to access.  Others (like the
   * IVA) have idiosyncratic reset sequences.  So for these relatively
   * rare cases, custom reset code can be supplied in the struct
   * omap_hwmod_class .reset function pointer.
   *
   * _set_dmadisable() is called to set the DMADISABLE bit so that it
   * does not prevent idling of the system. This is necessary for cases
   * where ROMCODE/BOOTLOADER uses dma and transfers control to the
   * kernel without disabling dma.
   *
   * Passes along the return value from either _ocp_softreset() or the
   * custom reset function - these must return -EINVAL if the hwmod
   * cannot be reset this way or if the hwmod is in the wrong state,
   * -ETIMEDOUT if the module did not reset in time, or 0 upon success.
   */
  static int _reset(struct omap_hwmod *oh)
  {
  	int i, r;
  
  	pr_debug("omap_hwmod: %s: resetting\n", oh->name);
  
  	if (oh->class->reset) {
  		r = oh->class->reset(oh);
  	} else {
  		if (oh->rst_lines_cnt > 0) {
  			for (i = 0; i < oh->rst_lines_cnt; i++)
  				_assert_hardreset(oh, oh->rst_lines[i].name);
  			return 0;
  		} else {
  			r = _ocp_softreset(oh);
  			if (r == -ENOENT)
  				r = 0;
  		}
  	}
  
  	_set_dmadisable(oh);
  
  	/*
  	 * OCP_SYSCONFIG bits need to be reprogrammed after a
  	 * softreset.  The _enable() function should be split to avoid
  	 * the rewrite of the OCP_SYSCONFIG register.
  	 */
  	if (oh->class->sysc) {
  		_update_sysc_cache(oh);
  		_enable_sysc(oh);
  	}
  
  	return r;
  }
  
  /**
   * _reconfigure_io_chain - clear any I/O chain wakeups and reconfigure chain
   *
   * Call the appropriate PRM function to clear any logged I/O chain
   * wakeups and to reconfigure the chain.  This apparently needs to be
   * done upon every mux change.  Since hwmods can be concurrently
   * enabled and idled, hold a spinlock around the I/O chain
   * reconfiguration sequence.  No return value.
   *
   * XXX When the PRM code is moved to drivers, this function can be removed,
   * as the PRM infrastructure should abstract this.
   */
  static void _reconfigure_io_chain(void)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&io_chain_lock, flags);
  
  	if (cpu_is_omap34xx() && omap3_has_io_chain_ctrl())
  		omap3xxx_prm_reconfigure_io_chain();
  	else if (cpu_is_omap44xx())
  		omap44xx_prm_reconfigure_io_chain();
  
  	spin_unlock_irqrestore(&io_chain_lock, flags);
  }
  
  /**
   * _omap4_update_context_lost - increment hwmod context loss counter if
   * hwmod context was lost, and clear hardware context loss reg
   * @oh: hwmod to check for context loss
   *
   * If the PRCM indicates that the hwmod @oh lost context, increment
   * our in-memory context loss counter, and clear the RM_*_CONTEXT
   * bits. No return value.
   */
  static void _omap4_update_context_lost(struct omap_hwmod *oh)
  {
  	if (oh->prcm.omap4.flags & HWMOD_OMAP4_NO_CONTEXT_LOSS_BIT)
  		return;
  
  	if (!prm_was_any_context_lost_old(oh->clkdm->pwrdm.ptr->prcm_partition,
  					  oh->clkdm->pwrdm.ptr->prcm_offs,
  					  oh->prcm.omap4.context_offs))
  		return;
  
  	oh->prcm.omap4.context_lost_counter++;
  	prm_clear_context_loss_flags_old(oh->clkdm->pwrdm.ptr->prcm_partition,
  					 oh->clkdm->pwrdm.ptr->prcm_offs,
  					 oh->prcm.omap4.context_offs);
  }
  
  /**
   * _omap4_get_context_lost - get context loss counter for a hwmod
   * @oh: hwmod to get context loss counter for
   *
   * Returns the in-memory context loss counter for a hwmod.
   */
  static int _omap4_get_context_lost(struct omap_hwmod *oh)
  {
  	return oh->prcm.omap4.context_lost_counter;
  }
  
  /**
   * _enable_preprogram - Pre-program an IP block during the _enable() process
   * @oh: struct omap_hwmod *
   *
   * Some IP blocks (such as AESS) require some additional programming
   * after enable before they can enter idle.  If a function pointer to
   * do so is present in the hwmod data, then call it and pass along the
   * return value; otherwise, return 0.
   */
  static int _enable_preprogram(struct omap_hwmod *oh)
  {
  	if (!oh->class->enable_preprogram)
  		return 0;
  
  	return oh->class->enable_preprogram(oh);
  }
  
  /**
   * _enable - enable an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Enables an omap_hwmod @oh such that the MPU can access the hwmod's
   * register target.  Returns -EINVAL if the hwmod is in the wrong
   * state or passes along the return value of _wait_target_ready().
   */
  static int _enable(struct omap_hwmod *oh)
  {
  	int r;
  	int hwsup = 0;
  
  	pr_debug("omap_hwmod: %s: enabling\n", oh->name);
  
  	/*
  	 * hwmods with HWMOD_INIT_NO_IDLE flag set are left in enabled
  	 * state at init.  Now that someone is really trying to enable
  	 * them, just ensure that the hwmod mux is set.
  	 */
  	if (oh->_int_flags & _HWMOD_SKIP_ENABLE) {
  		/*
  		 * If the caller has mux data populated, do the mux'ing
  		 * which wouldn't have been done as part of the _enable()
  		 * done during setup.
  		 */
  		if (oh->mux)
  			omap_hwmod_mux(oh->mux, _HWMOD_STATE_ENABLED);
  
  		oh->_int_flags &= ~_HWMOD_SKIP_ENABLE;
  		return 0;
  	}
  
  	if (oh->_state != _HWMOD_STATE_INITIALIZED &&
  	    oh->_state != _HWMOD_STATE_IDLE &&
  	    oh->_state != _HWMOD_STATE_DISABLED) {
  		WARN(1, "omap_hwmod: %s: enabled state can only be entered from initialized, idle, or disabled state\n",
  			oh->name);
  		return -EINVAL;
  	}
  
  	/*
  	 * If an IP block contains HW reset lines and all of them are
  	 * asserted, we let integration code associated with that
  	 * block handle the enable.  We've received very little
  	 * information on what those driver authors need, and until
  	 * detailed information is provided and the driver code is
  	 * posted to the public lists, this is probably the best we
  	 * can do.
  	 */
  	if (_are_all_hardreset_lines_asserted(oh))
  		return 0;
  
  	/* Mux pins for device runtime if populated */
  	if (oh->mux && (!oh->mux->enabled ||
  			((oh->_state == _HWMOD_STATE_IDLE) &&
  			 oh->mux->pads_dynamic))) {
  		omap_hwmod_mux(oh->mux, _HWMOD_STATE_ENABLED);
  		_reconfigure_io_chain();
  	}
  
  	_add_initiator_dep(oh, mpu_oh);
  
  	if (oh->clkdm) {
  		/*
  		 * A clockdomain must be in SW_SUP before enabling
  		 * completely the module. The clockdomain can be set
  		 * in HW_AUTO only when the module become ready.
  		 */
  		hwsup = clkdm_in_hwsup(oh->clkdm) &&
  			!clkdm_missing_idle_reporting(oh->clkdm);
  		r = clkdm_hwmod_enable(oh->clkdm, oh);
  		if (r) {
  			WARN(1, "omap_hwmod: %s: could not enable clockdomain %s: %d\n",
  			     oh->name, oh->clkdm->name, r);
  			return r;
  		}
  	}
  
  	_enable_clocks(oh);
  	if (soc_ops.enable_module)
  		soc_ops.enable_module(oh);
  	if (oh->flags & HWMOD_BLOCK_WFI)
  		cpu_idle_poll_ctrl(true);
  
  	if (soc_ops.update_context_lost)
  		soc_ops.update_context_lost(oh);
  
  	r = (soc_ops.wait_target_ready) ? soc_ops.wait_target_ready(oh) :
  		-EINVAL;
  	if (!r) {
  		/*
  		 * Set the clockdomain to HW_AUTO only if the target is ready,
  		 * assuming that the previous state was HW_AUTO
  		 */
  		if (oh->clkdm && hwsup)
  			clkdm_allow_idle(oh->clkdm);
  
  		oh->_state = _HWMOD_STATE_ENABLED;
  
  		/* Access the sysconfig only if the target is ready */
  		if (oh->class->sysc) {
  			if (!(oh->_int_flags & _HWMOD_SYSCONFIG_LOADED))
  				_update_sysc_cache(oh);
  			_enable_sysc(oh);
  		}
  		r = _enable_preprogram(oh);
  	} else {
  		if (soc_ops.disable_module)
  			soc_ops.disable_module(oh);
  		_disable_clocks(oh);
  		pr_debug("omap_hwmod: %s: _wait_target_ready: %d\n",
  			 oh->name, r);
  
  		if (oh->clkdm)
  			clkdm_hwmod_disable(oh->clkdm, oh);
  	}
  
  	return r;
  }
  
  /**
   * _idle - idle an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Idles an omap_hwmod @oh.  This should be called once the hwmod has
   * no further work.  Returns -EINVAL if the hwmod is in the wrong
   * state or returns 0.
   */
  static int _idle(struct omap_hwmod *oh)
  {
  	pr_debug("omap_hwmod: %s: idling\n", oh->name);
  
  	if (oh->_state != _HWMOD_STATE_ENABLED) {
  		WARN(1, "omap_hwmod: %s: idle state can only be entered from enabled state\n",
  			oh->name);
  		return -EINVAL;
  	}
  
  	if (_are_all_hardreset_lines_asserted(oh))
  		return 0;
  
  	if (oh->class->sysc)
  		_idle_sysc(oh);
  	_del_initiator_dep(oh, mpu_oh);
  
  	if (oh->flags & HWMOD_BLOCK_WFI)
  		cpu_idle_poll_ctrl(false);
  	if (soc_ops.disable_module)
  		soc_ops.disable_module(oh);
  
  	/*
  	 * The module must be in idle mode before disabling any parents
  	 * clocks. Otherwise, the parent clock might be disabled before
  	 * the module transition is done, and thus will prevent the
  	 * transition to complete properly.
  	 */
  	_disable_clocks(oh);
  	if (oh->clkdm)
  		clkdm_hwmod_disable(oh->clkdm, oh);
  
  	/* Mux pins for device idle if populated */
  	if (oh->mux && oh->mux->pads_dynamic) {
  		omap_hwmod_mux(oh->mux, _HWMOD_STATE_IDLE);
  		_reconfigure_io_chain();
  	}
  
  	oh->_state = _HWMOD_STATE_IDLE;
  
  	return 0;
  }
  
  /**
   * _shutdown - shutdown an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Shut down an omap_hwmod @oh.  This should be called when the driver
   * used for the hwmod is removed or unloaded or if the driver is not
   * used by the system.  Returns -EINVAL if the hwmod is in the wrong
   * state or returns 0.
   */
  static int _shutdown(struct omap_hwmod *oh)
  {
  	int ret, i;
  	u8 prev_state;
  
  	if (oh->_state != _HWMOD_STATE_IDLE &&
  	    oh->_state != _HWMOD_STATE_ENABLED) {
  		WARN(1, "omap_hwmod: %s: disabled state can only be entered from idle, or enabled state\n",
  			oh->name);
  		return -EINVAL;
  	}
  
  	if (_are_all_hardreset_lines_asserted(oh))
  		return 0;
  
  	pr_debug("omap_hwmod: %s: disabling\n", oh->name);
  
  	if (oh->class->pre_shutdown) {
  		prev_state = oh->_state;
  		if (oh->_state == _HWMOD_STATE_IDLE)
  			_enable(oh);
  		ret = oh->class->pre_shutdown(oh);
  		if (ret) {
  			if (prev_state == _HWMOD_STATE_IDLE)
  				_idle(oh);
  			return ret;
  		}
  	}
  
  	if (oh->class->sysc) {
  		if (oh->_state == _HWMOD_STATE_IDLE)
  			_enable(oh);
  		_shutdown_sysc(oh);
  	}
  
  	/* clocks and deps are already disabled in idle */
  	if (oh->_state == _HWMOD_STATE_ENABLED) {
  		_del_initiator_dep(oh, mpu_oh);
  		/* XXX what about the other system initiators here? dma, dsp */
  		if (oh->flags & HWMOD_BLOCK_WFI)
  			cpu_idle_poll_ctrl(false);
  		if (soc_ops.disable_module)
  			soc_ops.disable_module(oh);
  		_disable_clocks(oh);
  		if (oh->clkdm)
  			clkdm_hwmod_disable(oh->clkdm, oh);
  	}
  	/* XXX Should this code also force-disable the optional clocks? */
  
  	for (i = 0; i < oh->rst_lines_cnt; i++)
  		_assert_hardreset(oh, oh->rst_lines[i].name);
  
  	/* Mux pins to safe mode or use populated off mode values */
  	if (oh->mux)
  		omap_hwmod_mux(oh->mux, _HWMOD_STATE_DISABLED);
  
  	oh->_state = _HWMOD_STATE_DISABLED;
  
  	return 0;
  }
  
  /**
   * of_dev_hwmod_lookup - look up needed hwmod from dt blob
   * @np: struct device_node *
   * @oh: struct omap_hwmod *
   *
   * Parse the dt blob and find out needed hwmod. Recursive function is
   * implemented to take care hierarchical dt blob parsing.
   * Return: The device node on success or NULL on failure.
   */
  static struct device_node *of_dev_hwmod_lookup(struct device_node *np,
  						struct omap_hwmod *oh)
  {
  	struct device_node *np0 = NULL, *np1 = NULL;
  	const char *p;
  
  	for_each_child_of_node(np, np0) {
  		if (of_find_property(np0, "ti,hwmods", NULL)) {
  			p = of_get_property(np0, "ti,hwmods", NULL);
  			if (!strcmp(p, oh->name))
  				return np0;
  			np1 = of_dev_hwmod_lookup(np0, oh);
  			if (np1)
  				return np1;
  		}
  	}
  	return NULL;
  }
  
  /**
   * _init_mpu_rt_base - populate the virtual address for a hwmod
   * @oh: struct omap_hwmod * to locate the virtual address
   *
   * Cache the virtual address used by the MPU to access this IP block's
   * registers.  This address is needed early so the OCP registers that
   * are part of the device's address space can be ioremapped properly.
   * No return value.
   */
  static void __init _init_mpu_rt_base(struct omap_hwmod *oh, void *data)
  {
  	struct omap_hwmod_addr_space *mem;
  	void __iomem *va_start = NULL;
  	struct device_node *np;
  
  	if (!oh)
  		return;
  
  	_save_mpu_port_index(oh);
  
  	if (oh->_int_flags & _HWMOD_NO_MPU_PORT)
  		return;
  
  	mem = _find_mpu_rt_addr_space(oh);
  	if (!mem) {
  		pr_debug("omap_hwmod: %s: no MPU register target found\n",
  			 oh->name);
  
  		/* Extract the IO space from device tree blob */
  		if (!of_have_populated_dt())
  			return;
  
  		np = of_dev_hwmod_lookup(of_find_node_by_name(NULL, "ocp"), oh);
  		if (np)
  			va_start = of_iomap(np, 0);
  	} else {
  		va_start = ioremap(mem->pa_start, mem->pa_end - mem->pa_start);
  	}
  
  	if (!va_start) {
  		pr_err("omap_hwmod: %s: Could not ioremap\n", oh->name);
  		return;
  	}
  
  	pr_debug("omap_hwmod: %s: MPU register target at va %p\n",
  		 oh->name, va_start);
  
  	oh->_mpu_rt_va = va_start;
  }
  
  /**
   * _init - initialize internal data for the hwmod @oh
   * @oh: struct omap_hwmod *
   * @n: (unused)
   *
   * Look up the clocks and the address space used by the MPU to access
   * registers belonging to the hwmod @oh.  @oh must already be
   * registered at this point.  This is the first of two phases for
   * hwmod initialization.  Code called here does not touch any hardware
   * registers, it simply prepares internal data structures.  Returns 0
   * upon success or if the hwmod isn't registered, or -EINVAL upon
   * failure.
   */
  static int __init _init(struct omap_hwmod *oh, void *data)
  {
  	int r;
  
  	if (oh->_state != _HWMOD_STATE_REGISTERED)
  		return 0;
  
  	if (oh->class->sysc)
  		_init_mpu_rt_base(oh, NULL);
  
  	r = _init_clocks(oh, NULL);
  	if (r < 0) {
  		WARN(1, "omap_hwmod: %s: couldn't init clocks\n", oh->name);
  		return -EINVAL;
  	}
  
  	oh->_state = _HWMOD_STATE_INITIALIZED;
  
  	return 0;
  }
  
  /**
   * _setup_iclk_autoidle - configure an IP block's interface clocks
   * @oh: struct omap_hwmod *
   *
   * Set up the module's interface clocks.  XXX This function is still mostly
   * a stub; implementing this properly requires iclk autoidle usecounting in
   * the clock code.   No return value.
   */
  static void __init _setup_iclk_autoidle(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_ocp_if *os;
  	struct list_head *p;
  	int i = 0;
  	if (oh->_state != _HWMOD_STATE_INITIALIZED)
  		return;
  
  	p = oh->slave_ports.next;
  
  	while (i < oh->slaves_cnt) {
  		os = _fetch_next_ocp_if(&p, &i);
  		if (!os->_clk)
  			continue;
  
  		if (os->flags & OCPIF_SWSUP_IDLE) {
  			/* XXX omap_iclk_deny_idle(c); */
  		} else {
  			/* XXX omap_iclk_allow_idle(c); */
  			clk_enable(os->_clk);
  		}
  	}
  
  	return;
  }
  
  /**
   * _setup_reset - reset an IP block during the setup process
   * @oh: struct omap_hwmod *
   *
   * Reset the IP block corresponding to the hwmod @oh during the setup
   * process.  The IP block is first enabled so it can be successfully
   * reset.  Returns 0 upon success or a negative error code upon
   * failure.
   */
  static int __init _setup_reset(struct omap_hwmod *oh)
  {
  	int r;
  
  	if (oh->_state != _HWMOD_STATE_INITIALIZED)
  		return -EINVAL;
  
  	if (oh->flags & HWMOD_EXT_OPT_MAIN_CLK)
  		return -EPERM;
  
  	if (oh->rst_lines_cnt == 0) {
  		r = _enable(oh);
  		if (r) {
  			pr_warning("omap_hwmod: %s: cannot be enabled for reset (%d)\n",
  				   oh->name, oh->_state);
  			return -EINVAL;
  		}
  	}
  
  	if (!(oh->flags & HWMOD_INIT_NO_RESET))
  		r = _reset(oh);
  
  	return r;
  }
  
  /**
   * _setup_postsetup - transition to the appropriate state after _setup
   * @oh: struct omap_hwmod *
   *
   * Place an IP block represented by @oh into a "post-setup" state --
   * either IDLE, ENABLED, or DISABLED.  ("post-setup" simply means that
   * this function is called at the end of _setup().)  The postsetup
   * state for an IP block can be changed by calling
   * omap_hwmod_enter_postsetup_state() early in the boot process,
   * before one of the omap_hwmod_setup*() functions are called for the
   * IP block.
   *
   * The IP block stays in this state until a PM runtime-based driver is
   * loaded for that IP block.  A post-setup state of IDLE is
   * appropriate for almost all IP blocks with runtime PM-enabled
   * drivers, since those drivers are able to enable the IP block.  A
   * post-setup state of ENABLED is appropriate for kernels with PM
   * runtime disabled.  The DISABLED state is appropriate for unusual IP
   * blocks such as the MPU WDTIMER on kernels without WDTIMER drivers
   * included, since the WDTIMER starts running on reset and will reset
   * the MPU if left active.
   *
   * This post-setup mechanism is deprecated.  Once all of the OMAP
   * drivers have been converted to use PM runtime, and all of the IP
   * block data and interconnect data is available to the hwmod code, it
   * should be possible to replace this mechanism with a "lazy reset"
   * arrangement.  In a "lazy reset" setup, each IP block is enabled
   * when the driver first probes, then all remaining IP blocks without
   * drivers are either shut down or enabled after the drivers have
   * loaded.  However, this cannot take place until the above
   * preconditions have been met, since otherwise the late reset code
   * has no way of knowing which IP blocks are in use by drivers, and
   * which ones are unused.
   *
   * No return value.
   */
  static void __init _setup_postsetup(struct omap_hwmod *oh)
  {
  	u8 postsetup_state;
  
  	if (oh->rst_lines_cnt > 0)
  		return;
  
  	postsetup_state = oh->_postsetup_state;
  	if (postsetup_state == _HWMOD_STATE_UNKNOWN)
  		postsetup_state = _HWMOD_STATE_ENABLED;
  
  	/*
  	 * XXX HWMOD_INIT_NO_IDLE does not belong in hwmod data -
  	 * it should be set by the core code as a runtime flag during startup
  	 */
  	if ((oh->flags & HWMOD_INIT_NO_IDLE) &&
  	    (postsetup_state == _HWMOD_STATE_IDLE)) {
  		oh->_int_flags |= _HWMOD_SKIP_ENABLE;
  		postsetup_state = _HWMOD_STATE_ENABLED;
  	}
  
  	if (postsetup_state == _HWMOD_STATE_IDLE)
  		_idle(oh);
  	else if (postsetup_state == _HWMOD_STATE_DISABLED)
  		_shutdown(oh);
  	else if (postsetup_state != _HWMOD_STATE_ENABLED)
  		WARN(1, "hwmod: %s: unknown postsetup state %d! defaulting to enabled\n",
  		     oh->name, postsetup_state);
  
  	return;
  }
  
  /**
   * _setup - prepare IP block hardware for use
   * @oh: struct omap_hwmod *
   * @n: (unused, pass NULL)
   *
   * Configure the IP block represented by @oh.  This may include
   * enabling the IP block, resetting it, and placing it into a
   * post-setup state, depending on the type of IP block and applicable
   * flags.  IP blocks are reset to prevent any previous configuration
   * by the bootloader or previous operating system from interfering
   * with power management or other parts of the system.  The reset can
   * be avoided; see omap_hwmod_no_setup_reset().  This is the second of
   * two phases for hwmod initialization.  Code called here generally
   * affects the IP block hardware, or system integration hardware
   * associated with the IP block.  Returns 0.
   */
  static int __init _setup(struct omap_hwmod *oh, void *data)
  {
  	if (oh->_state != _HWMOD_STATE_INITIALIZED)
  		return 0;
  
  	_setup_iclk_autoidle(oh);
  
  	if (!_setup_reset(oh))
  		_setup_postsetup(oh);
  
  	return 0;
  }
  
  /**
   * _register - register a struct omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Registers the omap_hwmod @oh.  Returns -EEXIST if an omap_hwmod
   * already has been registered by the same name; -EINVAL if the
   * omap_hwmod is in the wrong state, if @oh is NULL, if the
   * omap_hwmod's class field is NULL; if the omap_hwmod is missing a
   * name, or if the omap_hwmod's class is missing a name; or 0 upon
   * success.
   *
   * XXX The data should be copied into bootmem, so the original data
   * should be marked __initdata and freed after init.  This would allow
   * unneeded omap_hwmods to be freed on multi-OMAP configurations.  Note
   * that the copy process would be relatively complex due to the large number
   * of substructures.
   */
  static int __init _register(struct omap_hwmod *oh)
  {
  	if (!oh || !oh->name || !oh->class || !oh->class->name ||
  	    (oh->_state != _HWMOD_STATE_UNKNOWN))
  		return -EINVAL;
  
  	pr_debug("omap_hwmod: %s: registering\n", oh->name);
  
  	if (_lookup(oh->name))
  		return -EEXIST;
  
  	list_add_tail(&oh->node, &omap_hwmod_list);
  
  	INIT_LIST_HEAD(&oh->master_ports);
  	INIT_LIST_HEAD(&oh->slave_ports);
  	spin_lock_init(&oh->_lock);
  
  	oh->_state = _HWMOD_STATE_REGISTERED;
  
  	/*
  	 * XXX Rather than doing a strcmp(), this should test a flag
  	 * set in the hwmod data, inserted by the autogenerator code.
  	 */
  	if (!strcmp(oh->name, MPU_INITIATOR_NAME))
  		mpu_oh = oh;
  
  	return 0;
  }
  
  /**
   * _alloc_links - return allocated memory for hwmod links
   * @ml: pointer to a struct omap_hwmod_link * for the master link
   * @sl: pointer to a struct omap_hwmod_link * for the slave link
   *
   * Return pointers to two struct omap_hwmod_link records, via the
   * addresses pointed to by @ml and @sl.  Will first attempt to return
   * memory allocated as part of a large initial block, but if that has
   * been exhausted, will allocate memory itself.  Since ideally this
   * second allocation path will never occur, the number of these
   * 'supplemental' allocations will be logged when debugging is
   * enabled.  Returns 0.
   */
  static int __init _alloc_links(struct omap_hwmod_link **ml,
  			       struct omap_hwmod_link **sl)
  {
  	unsigned int sz;
  
  	if ((free_ls + LINKS_PER_OCP_IF) <= max_ls) {
  		*ml = &linkspace[free_ls++];
  		*sl = &linkspace[free_ls++];
  		return 0;
  	}
  
  	sz = sizeof(struct omap_hwmod_link) * LINKS_PER_OCP_IF;
  
  	*sl = NULL;
  	*ml = alloc_bootmem(sz);
  
  	memset(*ml, 0, sz);
  
  	*sl = (void *)(*ml) + sizeof(struct omap_hwmod_link);
  
  	ls_supp++;
  	pr_debug("omap_hwmod: supplemental link allocations needed: %d\n",
  		 ls_supp * LINKS_PER_OCP_IF);
  
  	return 0;
  };
  
  /**
   * _add_link - add an interconnect between two IP blocks
   * @oi: pointer to a struct omap_hwmod_ocp_if record
   *
   * Add struct omap_hwmod_link records connecting the master IP block
   * specified in @oi->master to @oi, and connecting the slave IP block
   * specified in @oi->slave to @oi.  This code is assumed to run before
   * preemption or SMP has been enabled, thus avoiding the need for
   * locking in this code.  Changes to this assumption will require
   * additional locking.  Returns 0.
   */
  static int __init _add_link(struct omap_hwmod_ocp_if *oi)
  {
  	struct omap_hwmod_link *ml, *sl;
  
  	pr_debug("omap_hwmod: %s -> %s: adding link\n", oi->master->name,
  		 oi->slave->name);
  
  	_alloc_links(&ml, &sl);
  
  	ml->ocp_if = oi;
  	INIT_LIST_HEAD(&ml->node);
  	list_add(&ml->node, &oi->master->master_ports);
  	oi->master->masters_cnt++;
  
  	sl->ocp_if = oi;
  	INIT_LIST_HEAD(&sl->node);
  	list_add(&sl->node, &oi->slave->slave_ports);
  	oi->slave->slaves_cnt++;
  
  	return 0;
  }
  
  /**
   * _register_link - register a struct omap_hwmod_ocp_if
   * @oi: struct omap_hwmod_ocp_if *
   *
   * Registers the omap_hwmod_ocp_if record @oi.  Returns -EEXIST if it
   * has already been registered; -EINVAL if @oi is NULL or if the
   * record pointed to by @oi is missing required fields; or 0 upon
   * success.
   *
   * XXX The data should be copied into bootmem, so the original data
   * should be marked __initdata and freed after init.  This would allow
   * unneeded omap_hwmods to be freed on multi-OMAP configurations.
   */
  static int __init _register_link(struct omap_hwmod_ocp_if *oi)
  {
  	if (!oi || !oi->master || !oi->slave || !oi->user)
  		return -EINVAL;
  
  	if (oi->_int_flags & _OCPIF_INT_FLAGS_REGISTERED)
  		return -EEXIST;
  
  	pr_debug("omap_hwmod: registering link from %s to %s\n",
  		 oi->master->name, oi->slave->name);
  
  	/*
  	 * Register the connected hwmods, if they haven't been
  	 * registered already
  	 */
  	if (oi->master->_state != _HWMOD_STATE_REGISTERED)
  		_register(oi->master);
  
  	if (oi->slave->_state != _HWMOD_STATE_REGISTERED)
  		_register(oi->slave);
  
  	_add_link(oi);
  
  	oi->_int_flags |= _OCPIF_INT_FLAGS_REGISTERED;
  
  	return 0;
  }
  
  /**
   * _alloc_linkspace - allocate large block of hwmod links
   * @ois: pointer to an array of struct omap_hwmod_ocp_if records to count
   *
   * Allocate a large block of struct omap_hwmod_link records.  This
   * improves boot time significantly by avoiding the need to allocate
   * individual records one by one.  If the number of records to
   * allocate in the block hasn't been manually specified, this function
   * will count the number of struct omap_hwmod_ocp_if records in @ois
   * and use that to determine the allocation size.  For SoC families
   * that require multiple list registrations, such as OMAP3xxx, this
   * estimation process isn't optimal, so manual estimation is advised
   * in those cases.  Returns -EEXIST if the allocation has already occurred
   * or 0 upon success.
   */
  static int __init _alloc_linkspace(struct omap_hwmod_ocp_if **ois)
  {
  	unsigned int i = 0;
  	unsigned int sz;
  
  	if (linkspace) {
  		WARN(1, "linkspace already allocated\n");
  		return -EEXIST;
  	}
  
  	if (max_ls == 0)
  		while (ois[i++])
  			max_ls += LINKS_PER_OCP_IF;
  
  	sz = sizeof(struct omap_hwmod_link) * max_ls;
  
  	pr_debug("omap_hwmod: %s: allocating %d byte linkspace (%d links)\n",
  		 __func__, sz, max_ls);
  
  	linkspace = alloc_bootmem(sz);
  
  	memset(linkspace, 0, sz);
  
  	return 0;
  }
  
  /* Static functions intended only for use in soc_ops field function pointers */
  
  /**
   * _omap2xxx_wait_target_ready - wait for a module to leave slave idle
   * @oh: struct omap_hwmod *
   *
   * Wait for a module @oh to leave slave idle.  Returns 0 if the module
   * does not have an IDLEST bit or if the module successfully leaves
   * slave idle; otherwise, pass along the return value of the
   * appropriate *_cm*_wait_module_ready() function.
   */
  static int _omap2xxx_wait_target_ready(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return -EINVAL;
  
  	if (oh->flags & HWMOD_NO_IDLEST)
  		return 0;
  
  	if (!_find_mpu_rt_port(oh))
  		return 0;
  
  	/* XXX check module SIDLEMODE, hardreset status, enabled clocks */
  
  	return omap2xxx_cm_wait_module_ready(oh->prcm.omap2.module_offs,
  					     oh->prcm.omap2.idlest_reg_id,
  					     oh->prcm.omap2.idlest_idle_bit);
  }
  
  /**
   * _omap3xxx_wait_target_ready - wait for a module to leave slave idle
   * @oh: struct omap_hwmod *
   *
   * Wait for a module @oh to leave slave idle.  Returns 0 if the module
   * does not have an IDLEST bit or if the module successfully leaves
   * slave idle; otherwise, pass along the return value of the
   * appropriate *_cm*_wait_module_ready() function.
   */
  static int _omap3xxx_wait_target_ready(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return -EINVAL;
  
  	if (oh->flags & HWMOD_NO_IDLEST)
  		return 0;
  
  	if (!_find_mpu_rt_port(oh))
  		return 0;
  
  	/* XXX check module SIDLEMODE, hardreset status, enabled clocks */
  
  	return omap3xxx_cm_wait_module_ready(oh->prcm.omap2.module_offs,
  					     oh->prcm.omap2.idlest_reg_id,
  					     oh->prcm.omap2.idlest_idle_bit);
  }
  
  /**
   * _omap4_wait_target_ready - wait for a module to leave slave idle
   * @oh: struct omap_hwmod *
   *
   * Wait for a module @oh to leave slave idle.  Returns 0 if the module
   * does not have an IDLEST bit or if the module successfully leaves
   * slave idle; otherwise, pass along the return value of the
   * appropriate *_cm*_wait_module_ready() function.
   */
  static int _omap4_wait_target_ready(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return -EINVAL;
  
  	if (oh->flags & HWMOD_NO_IDLEST || !oh->clkdm)
  		return 0;
  
  	if (!_find_mpu_rt_port(oh))
  		return 0;
  
  	/* XXX check module SIDLEMODE, hardreset status */
  
  	return omap4_cminst_wait_module_ready(oh->clkdm->prcm_partition,
  					      oh->clkdm->cm_inst,
  					      oh->clkdm->clkdm_offs,
  					      oh->prcm.omap4.clkctrl_offs);
  }
  
  /**
   * _am33xx_wait_target_ready - wait for a module to leave slave idle
   * @oh: struct omap_hwmod *
   *
   * Wait for a module @oh to leave slave idle.  Returns 0 if the module
   * does not have an IDLEST bit or if the module successfully leaves
   * slave idle; otherwise, pass along the return value of the
   * appropriate *_cm*_wait_module_ready() function.
   */
  static int _am33xx_wait_target_ready(struct omap_hwmod *oh)
  {
  	if (!oh || !oh->clkdm)
  		return -EINVAL;
  
  	if (oh->flags & HWMOD_NO_IDLEST)
  		return 0;
  
  	if (!_find_mpu_rt_port(oh))
  		return 0;
  
  	/* XXX check module SIDLEMODE, hardreset status */
  
  	return am33xx_cm_wait_module_ready(oh->clkdm->cm_inst,
  					      oh->clkdm->clkdm_offs,
  					      oh->prcm.omap4.clkctrl_offs);
  }
  
  /**
   * _omap2_assert_hardreset - call OMAP2 PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to assert hardreset
   * @ohri: hardreset line data
   *
   * Call omap2_prm_assert_hardreset() with parameters extracted from
   * the hwmod @oh and the hardreset line data @ohri.  Only intended for
   * use as an soc_ops function pointer.  Passes along the return value
   * from omap2_prm_assert_hardreset().  XXX This function is scheduled
   * for removal when the PRM code is moved into drivers/.
   */
  static int _omap2_assert_hardreset(struct omap_hwmod *oh,
  				   struct omap_hwmod_rst_info *ohri)
  {
  	return omap2_prm_assert_hardreset(oh->prcm.omap2.module_offs,
  					  ohri->rst_shift);
  }
  
  /**
   * _omap2_deassert_hardreset - call OMAP2 PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to deassert hardreset
   * @ohri: hardreset line data
   *
   * Call omap2_prm_deassert_hardreset() with parameters extracted from
   * the hwmod @oh and the hardreset line data @ohri.  Only intended for
   * use as an soc_ops function pointer.  Passes along the return value
   * from omap2_prm_deassert_hardreset().  XXX This function is
   * scheduled for removal when the PRM code is moved into drivers/.
   */
  static int _omap2_deassert_hardreset(struct omap_hwmod *oh,
  				     struct omap_hwmod_rst_info *ohri)
  {
  	return omap2_prm_deassert_hardreset(oh->prcm.omap2.module_offs,
  					    ohri->rst_shift,
  					    ohri->st_shift);
  }
  
  /**
   * _omap2_is_hardreset_asserted - call OMAP2 PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to test hardreset
   * @ohri: hardreset line data
   *
   * Call omap2_prm_is_hardreset_asserted() with parameters extracted
   * from the hwmod @oh and the hardreset line data @ohri.  Only
   * intended for use as an soc_ops function pointer.  Passes along the
   * return value from omap2_prm_is_hardreset_asserted().  XXX This
   * function is scheduled for removal when the PRM code is moved into
   * drivers/.
   */
  static int _omap2_is_hardreset_asserted(struct omap_hwmod *oh,
  					struct omap_hwmod_rst_info *ohri)
  {
  	return omap2_prm_is_hardreset_asserted(oh->prcm.omap2.module_offs,
  					       ohri->st_shift);
  }
  
  /**
   * _omap4_assert_hardreset - call OMAP4 PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to assert hardreset
   * @ohri: hardreset line data
   *
   * Call omap4_prminst_assert_hardreset() with parameters extracted
   * from the hwmod @oh and the hardreset line data @ohri.  Only
   * intended for use as an soc_ops function pointer.  Passes along the
   * return value from omap4_prminst_assert_hardreset().  XXX This
   * function is scheduled for removal when the PRM code is moved into
   * drivers/.
   */
  static int _omap4_assert_hardreset(struct omap_hwmod *oh,
  				   struct omap_hwmod_rst_info *ohri)
  {
  	if (!oh->clkdm)
  		return -EINVAL;
  
  	return omap4_prminst_assert_hardreset(ohri->rst_shift,
  				oh->clkdm->pwrdm.ptr->prcm_partition,
  				oh->clkdm->pwrdm.ptr->prcm_offs,
  				oh->prcm.omap4.rstctrl_offs);
  }
  
  /**
   * _omap4_deassert_hardreset - call OMAP4 PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to deassert hardreset
   * @ohri: hardreset line data
   *
   * Call omap4_prminst_deassert_hardreset() with parameters extracted
   * from the hwmod @oh and the hardreset line data @ohri.  Only
   * intended for use as an soc_ops function pointer.  Passes along the
   * return value from omap4_prminst_deassert_hardreset().  XXX This
   * function is scheduled for removal when the PRM code is moved into
   * drivers/.
   */
  static int _omap4_deassert_hardreset(struct omap_hwmod *oh,
  				     struct omap_hwmod_rst_info *ohri)
  {
  	if (!oh->clkdm)
  		return -EINVAL;
  
  	if (ohri->st_shift)
  		pr_err("omap_hwmod: %s: %s: hwmod data error: OMAP4 does not support st_shift\n",
  		       oh->name, ohri->name);
  	return omap4_prminst_deassert_hardreset(ohri->rst_shift,
  				oh->clkdm->pwrdm.ptr->prcm_partition,
  				oh->clkdm->pwrdm.ptr->prcm_offs,
  				oh->prcm.omap4.rstctrl_offs);
  }
  
  /**
   * _omap4_is_hardreset_asserted - call OMAP4 PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to test hardreset
   * @ohri: hardreset line data
   *
   * Call omap4_prminst_is_hardreset_asserted() with parameters
   * extracted from the hwmod @oh and the hardreset line data @ohri.
   * Only intended for use as an soc_ops function pointer.  Passes along
   * the return value from omap4_prminst_is_hardreset_asserted().  XXX
   * This function is scheduled for removal when the PRM code is moved
   * into drivers/.
   */
  static int _omap4_is_hardreset_asserted(struct omap_hwmod *oh,
  					struct omap_hwmod_rst_info *ohri)
  {
  	if (!oh->clkdm)
  		return -EINVAL;
  
  	return omap4_prminst_is_hardreset_asserted(ohri->rst_shift,
  				oh->clkdm->pwrdm.ptr->prcm_partition,
  				oh->clkdm->pwrdm.ptr->prcm_offs,
  				oh->prcm.omap4.rstctrl_offs);
  }
  
  /**
   * _am33xx_assert_hardreset - call AM33XX PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to assert hardreset
   * @ohri: hardreset line data
   *
   * Call am33xx_prminst_assert_hardreset() with parameters extracted
   * from the hwmod @oh and the hardreset line data @ohri.  Only
   * intended for use as an soc_ops function pointer.  Passes along the
   * return value from am33xx_prminst_assert_hardreset().  XXX This
   * function is scheduled for removal when the PRM code is moved into
   * drivers/.
   */
  static int _am33xx_assert_hardreset(struct omap_hwmod *oh,
  				   struct omap_hwmod_rst_info *ohri)
  
  {
  	return am33xx_prm_assert_hardreset(ohri->rst_shift,
  				oh->clkdm->pwrdm.ptr->prcm_offs,
  				oh->prcm.omap4.rstctrl_offs);
  }
  
  /**
   * _am33xx_deassert_hardreset - call AM33XX PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to deassert hardreset
   * @ohri: hardreset line data
   *
   * Call am33xx_prminst_deassert_hardreset() with parameters extracted
   * from the hwmod @oh and the hardreset line data @ohri.  Only
   * intended for use as an soc_ops function pointer.  Passes along the
   * return value from am33xx_prminst_deassert_hardreset().  XXX This
   * function is scheduled for removal when the PRM code is moved into
   * drivers/.
   */
  static int _am33xx_deassert_hardreset(struct omap_hwmod *oh,
  				     struct omap_hwmod_rst_info *ohri)
  {
  	return am33xx_prm_deassert_hardreset(ohri->rst_shift,
  				ohri->st_shift,
  				oh->clkdm->pwrdm.ptr->prcm_offs,
  				oh->prcm.omap4.rstctrl_offs,
  				oh->prcm.omap4.rstst_offs);
  }
  
  /**
   * _am33xx_is_hardreset_asserted - call AM33XX PRM hardreset fn with hwmod args
   * @oh: struct omap_hwmod * to test hardreset
   * @ohri: hardreset line data
   *
   * Call am33xx_prminst_is_hardreset_asserted() with parameters
   * extracted from the hwmod @oh and the hardreset line data @ohri.
   * Only intended for use as an soc_ops function pointer.  Passes along
   * the return value from am33xx_prminst_is_hardreset_asserted().  XXX
   * This function is scheduled for removal when the PRM code is moved
   * into drivers/.
   */
  static int _am33xx_is_hardreset_asserted(struct omap_hwmod *oh,
  					struct omap_hwmod_rst_info *ohri)
  {
  	return am33xx_prm_is_hardreset_asserted(ohri->rst_shift,
  				oh->clkdm->pwrdm.ptr->prcm_offs,
  				oh->prcm.omap4.rstctrl_offs);
  }
  
  /* Public functions */
  
  u32 omap_hwmod_read(struct omap_hwmod *oh, u16 reg_offs)
  {
  	if (oh->flags & HWMOD_16BIT_REG)
  		return __raw_readw(oh->_mpu_rt_va + reg_offs);
  	else
  		return __raw_readl(oh->_mpu_rt_va + reg_offs);
  }
  
  void omap_hwmod_write(u32 v, struct omap_hwmod *oh, u16 reg_offs)
  {
  	if (oh->flags & HWMOD_16BIT_REG)
  		__raw_writew(v, oh->_mpu_rt_va + reg_offs);
  	else
  		__raw_writel(v, oh->_mpu_rt_va + reg_offs);
  }
  
  /**
   * omap_hwmod_softreset - reset a module via SYSCONFIG.SOFTRESET bit
   * @oh: struct omap_hwmod *
   *
   * This is a public function exposed to drivers. Some drivers may need to do
   * some settings before and after resetting the device.  Those drivers after
   * doing the necessary settings could use this function to start a reset by
   * setting the SYSCONFIG.SOFTRESET bit.
   */
  int omap_hwmod_softreset(struct omap_hwmod *oh)
  {
  	u32 v;
  	int ret;
  
  	if (!oh || !(oh->_sysc_cache))
  		return -EINVAL;
  
  	v = oh->_sysc_cache;
  	ret = _set_softreset(oh, &v);
  	if (ret)
  		goto error;
  	_write_sysconfig(v, oh);
  
  	ret = _clear_softreset(oh, &v);
  	if (ret)
  		goto error;
  	_write_sysconfig(v, oh);
  
  error:
  	return ret;
  }
  
  /**
   * omap_hwmod_lookup - look up a registered omap_hwmod by name
   * @name: name of the omap_hwmod to look up
   *
   * Given a @name of an omap_hwmod, return a pointer to the registered
   * struct omap_hwmod *, or NULL upon error.
   */
  struct omap_hwmod *omap_hwmod_lookup(const char *name)
  {
  	struct omap_hwmod *oh;
  
  	if (!name)
  		return NULL;
  
  	oh = _lookup(name);
  
  	return oh;
  }
  
  /**
   * omap_hwmod_for_each - call function for each registered omap_hwmod
   * @fn: pointer to a callback function
   * @data: void * data to pass to callback function
   *
   * Call @fn for each registered omap_hwmod, passing @data to each
   * function.  @fn must return 0 for success or any other value for
   * failure.  If @fn returns non-zero, the iteration across omap_hwmods
   * will stop and the non-zero return value will be passed to the
   * caller of omap_hwmod_for_each().  @fn is called with
   * omap_hwmod_for_each() held.
   */
  int omap_hwmod_for_each(int (*fn)(struct omap_hwmod *oh, void *data),
  			void *data)
  {
  	struct omap_hwmod *temp_oh;
  	int ret = 0;
  
  	if (!fn)
  		return -EINVAL;
  
  	list_for_each_entry(temp_oh, &omap_hwmod_list, node) {
  		ret = (*fn)(temp_oh, data);
  		if (ret)
  			break;
  	}
  
  	return ret;
  }
  
  /**
   * omap_hwmod_register_links - register an array of hwmod links
   * @ois: pointer to an array of omap_hwmod_ocp_if to register
   *
   * Intended to be called early in boot before the clock framework is
   * initialized.  If @ois is not null, will register all omap_hwmods
   * listed in @ois that are valid for this chip.  Returns -EINVAL if
   * omap_hwmod_init() hasn't been called before calling this function,
   * -ENOMEM if the link memory area can't be allocated, or 0 upon
   * success.
   */
  int __init omap_hwmod_register_links(struct omap_hwmod_ocp_if **ois)
  {
  	int r, i;
  
  	if (!inited)
  		return -EINVAL;
  
  	if (!ois)
  		return 0;
  
  	if (!linkspace) {
  		if (_alloc_linkspace(ois)) {
  			pr_err("omap_hwmod: could not allocate link space\n");
  			return -ENOMEM;
  		}
  	}
  
  	i = 0;
  	do {
  		r = _register_link(ois[i]);
  		WARN(r && r != -EEXIST,
  		     "omap_hwmod: _register_link(%s -> %s) returned %d\n",
  		     ois[i]->master->name, ois[i]->slave->name, r);
  	} while (ois[++i]);
  
  	return 0;
  }
  
  /**
   * _ensure_mpu_hwmod_is_setup - ensure the MPU SS hwmod is init'ed and set up
   * @oh: pointer to the hwmod currently being set up (usually not the MPU)
   *
   * If the hwmod data corresponding to the MPU subsystem IP block
   * hasn't been initialized and set up yet, do so now.  This must be
   * done first since sleep dependencies may be added from other hwmods
   * to the MPU.  Intended to be called only by omap_hwmod_setup*().  No
   * return value.
   */
  static void __init _ensure_mpu_hwmod_is_setup(struct omap_hwmod *oh)
  {
  	if (!mpu_oh || mpu_oh->_state == _HWMOD_STATE_UNKNOWN)
  		pr_err("omap_hwmod: %s: MPU initiator hwmod %s not yet registered\n",
  		       __func__, MPU_INITIATOR_NAME);
  	else if (mpu_oh->_state == _HWMOD_STATE_REGISTERED && oh != mpu_oh)
  		omap_hwmod_setup_one(MPU_INITIATOR_NAME);
  }
  
  /**
   * omap_hwmod_setup_one - set up a single hwmod
   * @oh_name: const char * name of the already-registered hwmod to set up
   *
   * Initialize and set up a single hwmod.  Intended to be used for a
   * small number of early devices, such as the timer IP blocks used for
   * the scheduler clock.  Must be called after omap2_clk_init().
   * Resolves the struct clk names to struct clk pointers for each
   * registered omap_hwmod.  Also calls _setup() on each hwmod.  Returns
   * -EINVAL upon error or 0 upon success.
   */
  int __init omap_hwmod_setup_one(const char *oh_name)
  {
  	struct omap_hwmod *oh;
  
  	pr_debug("omap_hwmod: %s: %s\n", oh_name, __func__);
  
  	oh = _lookup(oh_name);
  	if (!oh) {
  		WARN(1, "omap_hwmod: %s: hwmod not yet registered\n", oh_name);
  		return -EINVAL;
  	}
  
  	_ensure_mpu_hwmod_is_setup(oh);
  
  	_init(oh, NULL);
  	_setup(oh, NULL);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_setup_all - set up all registered IP blocks
   *
   * Initialize and set up all IP blocks registered with the hwmod code.
   * Must be called after omap2_clk_init().  Resolves the struct clk
   * names to struct clk pointers for each registered omap_hwmod.  Also
   * calls _setup() on each hwmod.  Returns 0 upon success.
   */
  static int __init omap_hwmod_setup_all(void)
  {
  	_ensure_mpu_hwmod_is_setup(NULL);
  
  	omap_hwmod_for_each(_init, NULL);
  	omap_hwmod_for_each(_setup, NULL);
  
  	return 0;
  }
  omap_core_initcall(omap_hwmod_setup_all);
  
  /**
   * omap_hwmod_enable - enable an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Enable an omap_hwmod @oh.  Intended to be called by omap_device_enable().
   * Returns -EINVAL on error or passes along the return value from _enable().
   */
  int omap_hwmod_enable(struct omap_hwmod *oh)
  {
  	int r;
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	r = _enable(oh);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return r;
  }
  
  /**
   * omap_hwmod_idle - idle an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Idle an omap_hwmod @oh.  Intended to be called by omap_device_idle().
   * Returns -EINVAL on error or passes along the return value from _idle().
   */
  int omap_hwmod_idle(struct omap_hwmod *oh)
  {
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	_idle(oh);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_shutdown - shutdown an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Shutdown an omap_hwmod @oh.  Intended to be called by
   * omap_device_shutdown().  Returns -EINVAL on error or passes along
   * the return value from _shutdown().
   */
  int omap_hwmod_shutdown(struct omap_hwmod *oh)
  {
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	_shutdown(oh);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_enable_clocks - enable main_clk, all interface clocks
   * @oh: struct omap_hwmod *oh
   *
   * Intended to be called by the omap_device code.
   */
  int omap_hwmod_enable_clocks(struct omap_hwmod *oh)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	_enable_clocks(oh);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_disable_clocks - disable main_clk, all interface clocks
   * @oh: struct omap_hwmod *oh
   *
   * Intended to be called by the omap_device code.
   */
  int omap_hwmod_disable_clocks(struct omap_hwmod *oh)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	_disable_clocks(oh);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_ocp_barrier - wait for posted writes against the hwmod to complete
   * @oh: struct omap_hwmod *oh
   *
   * Intended to be called by drivers and core code when all posted
   * writes to a device must complete before continuing further
   * execution (for example, after clearing some device IRQSTATUS
   * register bits)
   *
   * XXX what about targets with multiple OCP threads?
   */
  void omap_hwmod_ocp_barrier(struct omap_hwmod *oh)
  {
  	BUG_ON(!oh);
  
  	if (!oh->class->sysc || !oh->class->sysc->sysc_flags) {
  		WARN(1, "omap_device: %s: OCP barrier impossible due to device configuration\n",
  			oh->name);
  		return;
  	}
  
  	/*
  	 * Forces posted writes to complete on the OCP thread handling
  	 * register writes
  	 */
  	omap_hwmod_read(oh, oh->class->sysc->sysc_offs);
  }
  
  /**
   * omap_hwmod_reset - reset the hwmod
   * @oh: struct omap_hwmod *
   *
   * Under some conditions, a driver may wish to reset the entire device.
   * Called from omap_device code.  Returns -EINVAL on error or passes along
   * the return value from _reset().
   */
  int omap_hwmod_reset(struct omap_hwmod *oh)
  {
  	int r;
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	r = _reset(oh);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return r;
  }
  
  /*
   * IP block data retrieval functions
   */
  
  /**
   * omap_hwmod_count_resources - count number of struct resources needed by hwmod
   * @oh: struct omap_hwmod *
   * @flags: Type of resources to include when counting (IRQ/DMA/MEM)
   *
   * Count the number of struct resource array elements necessary to
   * contain omap_hwmod @oh resources.  Intended to be called by code
   * that registers omap_devices.  Intended to be used to determine the
   * size of a dynamically-allocated struct resource array, before
   * calling omap_hwmod_fill_resources().  Returns the number of struct
   * resource array elements needed.
   *
   * XXX This code is not optimized.  It could attempt to merge adjacent
   * resource IDs.
   *
   */
  int omap_hwmod_count_resources(struct omap_hwmod *oh, unsigned long flags)
  {
  	int ret = 0;
  
  	if (flags & IORESOURCE_IRQ)
  		ret += _count_mpu_irqs(oh);
  
  	if (flags & IORESOURCE_DMA)
  		ret += _count_sdma_reqs(oh);
  
  	if (flags & IORESOURCE_MEM) {
  		int i = 0;
  		struct omap_hwmod_ocp_if *os;
  		struct list_head *p = oh->slave_ports.next;
  
  		while (i < oh->slaves_cnt) {
  			os = _fetch_next_ocp_if(&p, &i);
  			ret += _count_ocp_if_addr_spaces(os);
  		}
  	}
  
  	return ret;
  }
  
  /**
   * omap_hwmod_fill_resources - fill struct resource array with hwmod data
   * @oh: struct omap_hwmod *
   * @res: pointer to the first element of an array of struct resource to fill
   *
   * Fill the struct resource array @res with resource data from the
   * omap_hwmod @oh.  Intended to be called by code that registers
   * omap_devices.  See also omap_hwmod_count_resources().  Returns the
   * number of array elements filled.
   */
  int omap_hwmod_fill_resources(struct omap_hwmod *oh, struct resource *res)
  {
  	struct omap_hwmod_ocp_if *os;
  	struct list_head *p;
  	int i, j, mpu_irqs_cnt, sdma_reqs_cnt, addr_cnt;
  	int r = 0;
  
  	/* For each IRQ, DMA, memory area, fill in array.*/
  
  	mpu_irqs_cnt = _count_mpu_irqs(oh);
  	for (i = 0; i < mpu_irqs_cnt; i++) {
  		(res + r)->name = (oh->mpu_irqs + i)->name;
  		(res + r)->start = (oh->mpu_irqs + i)->irq;
  		(res + r)->end = (oh->mpu_irqs + i)->irq;
  		(res + r)->flags = IORESOURCE_IRQ;
  		r++;
  	}
  
  	sdma_reqs_cnt = _count_sdma_reqs(oh);
  	for (i = 0; i < sdma_reqs_cnt; i++) {
  		(res + r)->name = (oh->sdma_reqs + i)->name;
  		(res + r)->start = (oh->sdma_reqs + i)->dma_req;
  		(res + r)->end = (oh->sdma_reqs + i)->dma_req;
  		(res + r)->flags = IORESOURCE_DMA;
  		r++;
  	}
  
  	p = oh->slave_ports.next;
  
  	i = 0;
  	while (i < oh->slaves_cnt) {
  		os = _fetch_next_ocp_if(&p, &i);
  		addr_cnt = _count_ocp_if_addr_spaces(os);
  
  		for (j = 0; j < addr_cnt; j++) {
  			(res + r)->name = (os->addr + j)->name;
  			(res + r)->start = (os->addr + j)->pa_start;
  			(res + r)->end = (os->addr + j)->pa_end;
  			(res + r)->flags = IORESOURCE_MEM;
  			r++;
  		}
  	}
  
  	return r;
  }
  
  /**
   * omap_hwmod_fill_dma_resources - fill struct resource array with dma data
   * @oh: struct omap_hwmod *
   * @res: pointer to the array of struct resource to fill
   *
   * Fill the struct resource array @res with dma resource data from the
   * omap_hwmod @oh.  Intended to be called by code that registers
   * omap_devices.  See also omap_hwmod_count_resources().  Returns the
   * number of array elements filled.
   */
  int omap_hwmod_fill_dma_resources(struct omap_hwmod *oh, struct resource *res)
  {
  	int i, sdma_reqs_cnt;
  	int r = 0;
  
  	sdma_reqs_cnt = _count_sdma_reqs(oh);
  	for (i = 0; i < sdma_reqs_cnt; i++) {
  		(res + r)->name = (oh->sdma_reqs + i)->name;
  		(res + r)->start = (oh->sdma_reqs + i)->dma_req;
  		(res + r)->end = (oh->sdma_reqs + i)->dma_req;
  		(res + r)->flags = IORESOURCE_DMA;
  		r++;
  	}
  
  	return r;
  }
  
  /**
   * omap_hwmod_get_resource_byname - fetch IP block integration data by name
   * @oh: struct omap_hwmod * to operate on
   * @type: one of the IORESOURCE_* constants from include/linux/ioport.h
   * @name: pointer to the name of the data to fetch (optional)
   * @rsrc: pointer to a struct resource, allocated by the caller
   *
   * Retrieve MPU IRQ, SDMA request line, or address space start/end
   * data for the IP block pointed to by @oh.  The data will be filled
   * into a struct resource record pointed to by @rsrc.  The struct
   * resource must be allocated by the caller.  When @name is non-null,
   * the data associated with the matching entry in the IRQ/SDMA/address
   * space hwmod data arrays will be returned.  If @name is null, the
   * first array entry will be returned.  Data order is not meaningful
   * in hwmod data, so callers are strongly encouraged to use a non-null
   * @name whenever possible to avoid unpredictable effects if hwmod
   * data is later added that causes data ordering to change.  This
   * function is only intended for use by OMAP core code.  Device
   * drivers should not call this function - the appropriate bus-related
   * data accessor functions should be used instead.  Returns 0 upon
   * success or a negative error code upon error.
   */
  int omap_hwmod_get_resource_byname(struct omap_hwmod *oh, unsigned int type,
  				   const char *name, struct resource *rsrc)
  {
  	int r;
  	unsigned int irq, dma;
  	u32 pa_start, pa_end;
  
  	if (!oh || !rsrc)
  		return -EINVAL;
  
  	if (type == IORESOURCE_IRQ) {
  		r = _get_mpu_irq_by_name(oh, name, &irq);
  		if (r)
  			return r;
  
  		rsrc->start = irq;
  		rsrc->end = irq;
  	} else if (type == IORESOURCE_DMA) {
  		r = _get_sdma_req_by_name(oh, name, &dma);
  		if (r)
  			return r;
  
  		rsrc->start = dma;
  		rsrc->end = dma;
  	} else if (type == IORESOURCE_MEM) {
  		r = _get_addr_space_by_name(oh, name, &pa_start, &pa_end);
  		if (r)
  			return r;
  
  		rsrc->start = pa_start;
  		rsrc->end = pa_end;
  	} else {
  		return -EINVAL;
  	}
  
  	rsrc->flags = type;
  	rsrc->name = name;
  
  	return 0;
  }
  
  /**
   * omap_hwmod_get_pwrdm - return pointer to this module's main powerdomain
   * @oh: struct omap_hwmod *
   *
   * Return the powerdomain pointer associated with the OMAP module
   * @oh's main clock.  If @oh does not have a main clk, return the
   * powerdomain associated with the interface clock associated with the
   * module's MPU port. (XXX Perhaps this should use the SDMA port
   * instead?)  Returns NULL on error, or a struct powerdomain * on
   * success.
   */
  struct powerdomain *omap_hwmod_get_pwrdm(struct omap_hwmod *oh)
  {
  	struct clk *c;
  	struct omap_hwmod_ocp_if *oi;
  	struct clockdomain *clkdm;
  	struct clk_hw_omap *clk;
  
  	if (!oh)
  		return NULL;
  
  	if (oh->clkdm)
  		return oh->clkdm->pwrdm.ptr;
  
  	if (oh->_clk) {
  		c = oh->_clk;
  	} else {
  		oi = _find_mpu_rt_port(oh);
  		if (!oi)
  			return NULL;
  		c = oi->_clk;
  	}
  
  	clk = to_clk_hw_omap(__clk_get_hw(c));
  	clkdm = clk->clkdm;
  	if (!clkdm)
  		return NULL;
  
  	return clkdm->pwrdm.ptr;
  }
  
  /**
   * omap_hwmod_get_mpu_rt_va - return the module's base address (for the MPU)
   * @oh: struct omap_hwmod *
   *
   * Returns the virtual address corresponding to the beginning of the
   * module's register target, in the address range that is intended to
   * be used by the MPU.  Returns the virtual address upon success or NULL
   * upon error.
   */
  void __iomem *omap_hwmod_get_mpu_rt_va(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return NULL;
  
  	if (oh->_int_flags & _HWMOD_NO_MPU_PORT)
  		return NULL;
  
  	if (oh->_state == _HWMOD_STATE_UNKNOWN)
  		return NULL;
  
  	return oh->_mpu_rt_va;
  }
  
  /**
   * omap_hwmod_add_initiator_dep - add sleepdep from @init_oh to @oh
   * @oh: struct omap_hwmod *
   * @init_oh: struct omap_hwmod * (initiator)
   *
   * Add a sleep dependency between the initiator @init_oh and @oh.
   * Intended to be called by DSP/Bridge code via platform_data for the
   * DSP case; and by the DMA code in the sDMA case.  DMA code, *Bridge
   * code needs to add/del initiator dependencies dynamically
   * before/after accessing a device.  Returns the return value from
   * _add_initiator_dep().
   *
   * XXX Keep a usecount in the clockdomain code
   */
  int omap_hwmod_add_initiator_dep(struct omap_hwmod *oh,
  				 struct omap_hwmod *init_oh)
  {
  	return _add_initiator_dep(oh, init_oh);
  }
  
  /*
   * XXX what about functions for drivers to save/restore ocp_sysconfig
   * for context save/restore operations?
   */
  
  /**
   * omap_hwmod_del_initiator_dep - remove sleepdep from @init_oh to @oh
   * @oh: struct omap_hwmod *
   * @init_oh: struct omap_hwmod * (initiator)
   *
   * Remove a sleep dependency between the initiator @init_oh and @oh.
   * Intended to be called by DSP/Bridge code via platform_data for the
   * DSP case; and by the DMA code in the sDMA case.  DMA code, *Bridge
   * code needs to add/del initiator dependencies dynamically
   * before/after accessing a device.  Returns the return value from
   * _del_initiator_dep().
   *
   * XXX Keep a usecount in the clockdomain code
   */
  int omap_hwmod_del_initiator_dep(struct omap_hwmod *oh,
  				 struct omap_hwmod *init_oh)
  {
  	return _del_initiator_dep(oh, init_oh);
  }
  
  /**
   * omap_hwmod_enable_wakeup - allow device to wake up the system
   * @oh: struct omap_hwmod *
   *
   * Sets the module OCP socket ENAWAKEUP bit to allow the module to
   * send wakeups to the PRCM, and enable I/O ring wakeup events for
   * this IP block if it has dynamic mux entries.  Eventually this
   * should set PRCM wakeup registers to cause the PRCM to receive
   * wakeup events from the module.  Does not set any wakeup routing
   * registers beyond this point - if the module is to wake up any other
   * module or subsystem, that must be set separately.  Called by
   * omap_device code.  Returns -EINVAL on error or 0 upon success.
   */
  int omap_hwmod_enable_wakeup(struct omap_hwmod *oh)
  {
  	unsigned long flags;
  	u32 v;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  
  	if (oh->class->sysc &&
  	    (oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP)) {
  		v = oh->_sysc_cache;
  		_enable_wakeup(oh, &v);
  		_write_sysconfig(v, oh);
  	}
  
  	_set_idle_ioring_wakeup(oh, true);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_disable_wakeup - prevent device from waking the system
   * @oh: struct omap_hwmod *
   *
   * Clears the module OCP socket ENAWAKEUP bit to prevent the module
   * from sending wakeups to the PRCM, and disable I/O ring wakeup
   * events for this IP block if it has dynamic mux entries.  Eventually
   * this should clear PRCM wakeup registers to cause the PRCM to ignore
   * wakeup events from the module.  Does not set any wakeup routing
   * registers beyond this point - if the module is to wake up any other
   * module or subsystem, that must be set separately.  Called by
   * omap_device code.  Returns -EINVAL on error or 0 upon success.
   */
  int omap_hwmod_disable_wakeup(struct omap_hwmod *oh)
  {
  	unsigned long flags;
  	u32 v;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  
  	if (oh->class->sysc &&
  	    (oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP)) {
  		v = oh->_sysc_cache;
  		_disable_wakeup(oh, &v);
  		_write_sysconfig(v, oh);
  	}
  
  	_set_idle_ioring_wakeup(oh, false);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_assert_hardreset - assert the HW reset line of submodules
   * contained in the hwmod module.
   * @oh: struct omap_hwmod *
   * @name: name of the reset line to lookup and assert
   *
   * Some IP like dsp, ipu or iva contain processor that require
   * an HW reset line to be assert / deassert in order to enable fully
   * the IP.  Returns -EINVAL if @oh is null or if the operation is not
   * yet supported on this OMAP; otherwise, passes along the return value
   * from _assert_hardreset().
   */
  int omap_hwmod_assert_hardreset(struct omap_hwmod *oh, const char *name)
  {
  	int ret;
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	ret = _assert_hardreset(oh, name);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return ret;
  }
  
  /**
   * omap_hwmod_deassert_hardreset - deassert the HW reset line of submodules
   * contained in the hwmod module.
   * @oh: struct omap_hwmod *
   * @name: name of the reset line to look up and deassert
   *
   * Some IP like dsp, ipu or iva contain processor that require
   * an HW reset line to be assert / deassert in order to enable fully
   * the IP.  Returns -EINVAL if @oh is null or if the operation is not
   * yet supported on this OMAP; otherwise, passes along the return value
   * from _deassert_hardreset().
   */
  int omap_hwmod_deassert_hardreset(struct omap_hwmod *oh, const char *name)
  {
  	int ret;
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	ret = _deassert_hardreset(oh, name);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return ret;
  }
  
  /**
   * omap_hwmod_read_hardreset - read the HW reset line state of submodules
   * contained in the hwmod module
   * @oh: struct omap_hwmod *
   * @name: name of the reset line to look up and read
   *
   * Return the current state of the hwmod @oh's reset line named @name:
   * returns -EINVAL upon parameter error or if this operation
   * is unsupported on the current OMAP; otherwise, passes along the return
   * value from _read_hardreset().
   */
  int omap_hwmod_read_hardreset(struct omap_hwmod *oh, const char *name)
  {
  	int ret;
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  	ret = _read_hardreset(oh, name);
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return ret;
  }
  
  
  /**
   * omap_hwmod_for_each_by_class - call @fn for each hwmod of class @classname
   * @classname: struct omap_hwmod_class name to search for
   * @fn: callback function pointer to call for each hwmod in class @classname
   * @user: arbitrary context data to pass to the callback function
   *
   * For each omap_hwmod of class @classname, call @fn.
   * If the callback function returns something other than
   * zero, the iterator is terminated, and the callback function's return
   * value is passed back to the caller.  Returns 0 upon success, -EINVAL
   * if @classname or @fn are NULL, or passes back the error code from @fn.
   */
  int omap_hwmod_for_each_by_class(const char *classname,
  				 int (*fn)(struct omap_hwmod *oh,
  					   void *user),
  				 void *user)
  {
  	struct omap_hwmod *temp_oh;
  	int ret = 0;
  
  	if (!classname || !fn)
  		return -EINVAL;
  
  	pr_debug("omap_hwmod: %s: looking for modules of class %s\n",
  		 __func__, classname);
  
  	list_for_each_entry(temp_oh, &omap_hwmod_list, node) {
  		if (!strcmp(temp_oh->class->name, classname)) {
  			pr_debug("omap_hwmod: %s: %s: calling callback fn\n",
  				 __func__, temp_oh->name);
  			ret = (*fn)(temp_oh, user);
  			if (ret)
  				break;
  		}
  	}
  
  	if (ret)
  		pr_debug("omap_hwmod: %s: iterator terminated early: %d\n",
  			 __func__, ret);
  
  	return ret;
  }
  
  /**
   * omap_hwmod_set_postsetup_state - set the post-_setup() state for this hwmod
   * @oh: struct omap_hwmod *
   * @state: state that _setup() should leave the hwmod in
   *
   * Sets the hwmod state that @oh will enter at the end of _setup()
   * (called by omap_hwmod_setup_*()).  See also the documentation
   * for _setup_postsetup(), above.  Returns 0 upon success or
   * -EINVAL if there is a problem with the arguments or if the hwmod is
   * in the wrong state.
   */
  int omap_hwmod_set_postsetup_state(struct omap_hwmod *oh, u8 state)
  {
  	int ret;
  	unsigned long flags;
  
  	if (!oh)
  		return -EINVAL;
  
  	if (state != _HWMOD_STATE_DISABLED &&
  	    state != _HWMOD_STATE_ENABLED &&
  	    state != _HWMOD_STATE_IDLE)
  		return -EINVAL;
  
  	spin_lock_irqsave(&oh->_lock, flags);
  
  	if (oh->_state != _HWMOD_STATE_REGISTERED) {
  		ret = -EINVAL;
  		goto ohsps_unlock;
  	}
  
  	oh->_postsetup_state = state;
  	ret = 0;
  
  ohsps_unlock:
  	spin_unlock_irqrestore(&oh->_lock, flags);
  
  	return ret;
  }
  
  /**
   * omap_hwmod_get_context_loss_count - get lost context count
   * @oh: struct omap_hwmod *
   *
   * Returns the context loss count of associated @oh
   * upon success, or zero if no context loss data is available.
   *
   * On OMAP4, this queries the per-hwmod context loss register,
   * assuming one exists.  If not, or on OMAP2/3, this queries the
   * enclosing powerdomain context loss count.
   */
  int omap_hwmod_get_context_loss_count(struct omap_hwmod *oh)
  {
  	struct powerdomain *pwrdm;
  	int ret = 0;
  
  	if (soc_ops.get_context_lost)
  		return soc_ops.get_context_lost(oh);
  
  	pwrdm = omap_hwmod_get_pwrdm(oh);
  	if (pwrdm)
  		ret = pwrdm_get_context_loss_count(pwrdm);
  
  	return ret;
  }
  
  /**
   * omap_hwmod_no_setup_reset - prevent a hwmod from being reset upon setup
   * @oh: struct omap_hwmod *
   *
   * Prevent the hwmod @oh from being reset during the setup process.
   * Intended for use by board-*.c files on boards with devices that
   * cannot tolerate being reset.  Must be called before the hwmod has
   * been set up.  Returns 0 upon success or negative error code upon
   * failure.
   */
  int omap_hwmod_no_setup_reset(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return -EINVAL;
  
  	if (oh->_state != _HWMOD_STATE_REGISTERED) {
  		pr_err("omap_hwmod: %s: cannot prevent setup reset; in wrong state\n",
  			oh->name);
  		return -EINVAL;
  	}
  
  	oh->flags |= HWMOD_INIT_NO_RESET;
  
  	return 0;
  }
  
  /**
   * omap_hwmod_pad_route_irq - route an I/O pad wakeup to a particular MPU IRQ
   * @oh: struct omap_hwmod * containing hwmod mux entries
   * @pad_idx: array index in oh->mux of the hwmod mux entry to route wakeup
   * @irq_idx: the hwmod mpu_irqs array index of the IRQ to trigger on wakeup
   *
   * When an I/O pad wakeup arrives for the dynamic or wakeup hwmod mux
   * entry number @pad_idx for the hwmod @oh, trigger the interrupt
   * service routine for the hwmod's mpu_irqs array index @irq_idx.  If
   * this function is not called for a given pad_idx, then the ISR
   * associated with @oh's first MPU IRQ will be triggered when an I/O
   * pad wakeup occurs on that pad.  Note that @pad_idx is the index of
   * the _dynamic or wakeup_ entry: if there are other entries not
   * marked with OMAP_DEVICE_PAD_WAKEUP or OMAP_DEVICE_PAD_REMUX, these
   * entries are NOT COUNTED in the dynamic pad index.  This function
   * must be called separately for each pad that requires its interrupt
   * to be re-routed this way.  Returns -EINVAL if there is an argument
   * problem or if @oh does not have hwmod mux entries or MPU IRQs;
   * returns -ENOMEM if memory cannot be allocated; or 0 upon success.
   *
   * XXX This function interface is fragile.  Rather than using array
   * indexes, which are subject to unpredictable change, it should be
   * using hwmod IRQ names, and some other stable key for the hwmod mux
   * pad records.
   */
  int omap_hwmod_pad_route_irq(struct omap_hwmod *oh, int pad_idx, int irq_idx)
  {
  	int nr_irqs;
  
  	might_sleep();
  
  	if (!oh || !oh->mux || !oh->mpu_irqs || pad_idx < 0 ||
  	    pad_idx >= oh->mux->nr_pads_dynamic)
  		return -EINVAL;
  
  	/* Check the number of available mpu_irqs */
  	for (nr_irqs = 0; oh->mpu_irqs[nr_irqs].irq >= 0; nr_irqs++)
  		;
  
  	if (irq_idx >= nr_irqs)
  		return -EINVAL;
  
  	if (!oh->mux->irqs) {
  		/* XXX What frees this? */
  		oh->mux->irqs = kzalloc(sizeof(int) * oh->mux->nr_pads_dynamic,
  			GFP_KERNEL);
  		if (!oh->mux->irqs)
  			return -ENOMEM;
  	}
  	oh->mux->irqs[pad_idx] = irq_idx;
  
  	return 0;
  }
  
  /**
   * omap_hwmod_init - initialize the hwmod code
   *
   * Sets up some function pointers needed by the hwmod code to operate on the
   * currently-booted SoC.  Intended to be called once during kernel init
   * before any hwmods are registered.  No return value.
   */
  void __init omap_hwmod_init(void)
  {
  	if (cpu_is_omap24xx()) {
  		soc_ops.wait_target_ready = _omap2xxx_wait_target_ready;
  		soc_ops.assert_hardreset = _omap2_assert_hardreset;
  		soc_ops.deassert_hardreset = _omap2_deassert_hardreset;
  		soc_ops.is_hardreset_asserted = _omap2_is_hardreset_asserted;
  	} else if (cpu_is_omap34xx()) {
  		soc_ops.wait_target_ready = _omap3xxx_wait_target_ready;
  		soc_ops.assert_hardreset = _omap2_assert_hardreset;
  		soc_ops.deassert_hardreset = _omap2_deassert_hardreset;
  		soc_ops.is_hardreset_asserted = _omap2_is_hardreset_asserted;
  	} else if (cpu_is_omap44xx() || soc_is_omap54xx()) {
  		soc_ops.enable_module = _omap4_enable_module;
  		soc_ops.disable_module = _omap4_disable_module;
  		soc_ops.wait_target_ready = _omap4_wait_target_ready;
  		soc_ops.assert_hardreset = _omap4_assert_hardreset;
  		soc_ops.deassert_hardreset = _omap4_deassert_hardreset;
  		soc_ops.is_hardreset_asserted = _omap4_is_hardreset_asserted;
  		soc_ops.init_clkdm = _init_clkdm;
  		soc_ops.update_context_lost = _omap4_update_context_lost;
  		soc_ops.get_context_lost = _omap4_get_context_lost;
  	} else if (soc_is_am33xx()) {
  		soc_ops.enable_module = _am33xx_enable_module;
  		soc_ops.disable_module = _am33xx_disable_module;
  		soc_ops.wait_target_ready = _am33xx_wait_target_ready;
  		soc_ops.assert_hardreset = _am33xx_assert_hardreset;
  		soc_ops.deassert_hardreset = _am33xx_deassert_hardreset;
  		soc_ops.is_hardreset_asserted = _am33xx_is_hardreset_asserted;
  		soc_ops.init_clkdm = _init_clkdm;
  	} else {
  		WARN(1, "omap_hwmod: unknown SoC type\n");
  	}
  
  	inited = true;
  }
  
  /**
   * omap_hwmod_get_main_clk - get pointer to main clock name
   * @oh: struct omap_hwmod *
   *
   * Returns the main clock name assocated with @oh upon success,
   * or NULL if @oh is NULL.
   */
  const char *omap_hwmod_get_main_clk(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return NULL;
  
  	return oh->main_clk;
  }
  