text: /*
   * omap_hwmod implementation for OMAP2/3/4
   *
   * Copyright (C) 2009 Nokia Corporation
   *
   * 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.
   *
   * This code manages "OMAP modules" (on-chip devices) and their
   * integration with Linux device driver and bus code.
   *
   * References:
   * - 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:
   * - pin mux handling
   * - 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.h>
  #include <linux/delay.h>
  #include <linux/err.h>
  #include <linux/list.h>
  #include <linux/mutex.h>
  
  #include <plat/common.h>
  #include <plat/cpu.h>
  #include <plat/clockdomain.h>
  #include <plat/powerdomain.h>
  #include <plat/clock.h>
  #include <plat/omap_hwmod.h>
  
  #include "cm.h"
  
  /* Maximum microseconds to wait for OMAP module to reset */
  #define MAX_MODULE_RESET_WAIT		10000
  
  /* Name of the OMAP hwmod for the MPU */
  #define MPU_INITIATOR_NAME		"mpu"
  
  /* omap_hwmod_list contains all registered struct omap_hwmods */
  static LIST_HEAD(omap_hwmod_list);
  
  static DEFINE_MUTEX(omap_hwmod_mutex);
  
  /* mpu_oh: used to add/remove MPU initiator from sleepdep list */
  static struct omap_hwmod *mpu_oh;
  
  /* inited: 0 if omap_hwmod_init() has not yet been called; 1 otherwise */
  static u8 inited;
  
  
  /* Private functions */
  
  /**
   * _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_readl(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 */
  
  	if (oh->_sysc_cache != v) {
  		oh->_sysc_cache = v;
  		omap_hwmod_writel(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.CLOCKACTIVITY bits 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;
  }
  
  /**
   * _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 = (0x3 << autoidle_shift);
  
  	*v &= ~autoidle_mask;
  	*v |= autoidle << autoidle_shift;
  
  	return 0;
  }
  
  /**
   * _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, wakeup_mask;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
  		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;
  	}
  
  	wakeup_mask = (0x1 << oh->class->sysc->sysc_fields->enwkup_shift);
  
  	v = oh->_sysc_cache;
  	v |= wakeup_mask;
  	_write_sysconfig(v, oh);
  
  	/* XXX test pwrdm_get_wken for this hwmod's subsystem */
  
  	oh->_int_flags |= _HWMOD_WAKEUP_ENABLED;
  
  	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, wakeup_mask;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
  		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;
  	}
  
  	wakeup_mask = (0x1 << oh->class->sysc->sysc_fields->enwkup_shift);
  
  	v = oh->_sysc_cache;
  	v &= ~wakeup_mask;
  	_write_sysconfig(v, oh);
  
  	/* XXX test pwrdm_get_wken for this hwmod's subsystem */
  
  	oh->_int_flags &= ~_HWMOD_WAKEUP_ENABLED;
  
  	return 0;
  }
  
  /**
   * _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.  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)
  {
  	if (!oh->_clk)
  		return -EINVAL;
  
  	return clkdm_add_sleepdep(oh->_clk->clkdm, init_oh->_clk->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.  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)
  {
  	if (!oh->_clk)
  		return -EINVAL;
  
  	return clkdm_del_sleepdep(oh->_clk->clkdm, init_oh->_clk->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 = omap_clk_get_by_name(oh->main_clk);
  	if (!oh->_clk) {
  		pr_warning("omap_hwmod: %s: cannot clk_get main_clk %s\n",
  			   oh->name, oh->main_clk);
  		return -EINVAL;
  	}
  
  	if (!oh->_clk->clkdm)
  		pr_warning("omap_hwmod: %s: missing clockdomain for %s.\n",
  			   oh->main_clk, oh->_clk->name);
  
  	return ret;
  }
  
  /**
   * _init_interface_clk - 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 clk *c;
  	int i;
  	int ret = 0;
  
  	if (oh->slaves_cnt == 0)
  		return 0;
  
  	for (i = 0; i < oh->slaves_cnt; i++) {
  		struct omap_hwmod_ocp_if *os = oh->slaves[i];
  
  		if (!os->clk)
  			continue;
  
  		c = omap_clk_get_by_name(os->clk);
  		if (!c) {
  			pr_warning("omap_hwmod: %s: cannot clk_get interface_clk %s\n",
  				   oh->name, os->clk);
  			ret = -EINVAL;
  		}
  		os->_clk = c;
  	}
  
  	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 = omap_clk_get_by_name(oc->clk);
  		if (!c) {
  			pr_warning("omap_hwmod: %s: cannot clk_get opt_clk %s\n",
  				   oh->name, oc->clk);
  			ret = -EINVAL;
  		}
  		oc->_clk = c;
  	}
  
  	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)
  {
  	int i;
  
  	pr_debug("omap_hwmod: %s: enabling clocks\n", oh->name);
  
  	if (oh->_clk)
  		clk_enable(oh->_clk);
  
  	if (oh->slaves_cnt > 0) {
  		for (i = 0; i < oh->slaves_cnt; i++) {
  			struct omap_hwmod_ocp_if *os = oh->slaves[i];
  			struct clk *c = os->_clk;
  
  			if (c && (os->flags & OCPIF_SWSUP_IDLE))
  				clk_enable(c);
  		}
  	}
  
  	/* 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)
  {
  	int i;
  
  	pr_debug("omap_hwmod: %s: disabling clocks\n", oh->name);
  
  	if (oh->_clk)
  		clk_disable(oh->_clk);
  
  	if (oh->slaves_cnt > 0) {
  		for (i = 0; i < oh->slaves_cnt; i++) {
  			struct omap_hwmod_ocp_if *os = oh->slaves[i];
  			struct clk *c = os->_clk;
  
  			if (c && (os->flags & OCPIF_SWSUP_IDLE))
  				clk_disable(c);
  		}
  	}
  
  	/* The opt clocks are controlled by the device driver. */
  
  	return 0;
  }
  
  /**
   * _find_mpu_port_index - find hwmod OCP slave port ID intended for MPU use
   * @oh: struct omap_hwmod *
   *
   * Returns the array index of the OCP slave port that the MPU
   * addresses the device on, or -EINVAL upon error or not found.
   */
  static int _find_mpu_port_index(struct omap_hwmod *oh)
  {
  	int i;
  	int found = 0;
  
  	if (!oh || oh->slaves_cnt == 0)
  		return -EINVAL;
  
  	for (i = 0; i < oh->slaves_cnt; i++) {
  		struct omap_hwmod_ocp_if *os = oh->slaves[i];
  
  		if (os->user & OCP_USER_MPU) {
  			found = 1;
  			break;
  		}
  	}
  
  	if (found)
  		pr_debug("omap_hwmod: %s: MPU OCP slave port ID  %d\n",
  			 oh->name, i);
  	else
  		pr_debug("omap_hwmod: %s: no MPU OCP slave port found\n",
  			 oh->name);
  
  	return (found) ? i : -EINVAL;
  }
  
  /**
   * _find_mpu_rt_base - find hwmod register target base addr accessible by MPU
   * @oh: struct omap_hwmod *
   *
   * Return the virtual address of the base of the register target of
   * device @oh, or NULL on error.
   */
  static void __iomem *_find_mpu_rt_base(struct omap_hwmod *oh, u8 index)
  {
  	struct omap_hwmod_ocp_if *os;
  	struct omap_hwmod_addr_space *mem;
  	int i;
  	int found = 0;
  	void __iomem *va_start;
  
  	if (!oh || oh->slaves_cnt == 0)
  		return NULL;
  
  	os = oh->slaves[index];
  
  	for (i = 0, mem = os->addr; i < os->addr_cnt; i++, mem++) {
  		if (mem->flags & ADDR_TYPE_RT) {
  			found = 1;
  			break;
  		}
  	}
  
  	if (found) {
  		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 NULL;
  		}
  		pr_debug("omap_hwmod: %s: MPU register target at va %p\n",
  			 oh->name, va_start);
  	} else {
  		pr_debug("omap_hwmod: %s: no MPU register target found\n",
  			 oh->name);
  	}
  
  	return (found) ? va_start : NULL;
  }
  
  /**
   * _sysc_enable - try to bring a module out of idle via OCP_SYSCONFIG
   * @oh: struct omap_hwmod *
   *
   * If module is marked as SWSUP_SIDLE, force the module out of slave
   * idle; otherwise, configure it for smart-idle.  If module is marked
   * as SWSUP_MSUSPEND, force the module out of master standby;
   * otherwise, configure it for smart-standby.  No return value.
   */
  static void _sysc_enable(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) {
  		idlemode = (oh->flags & HWMOD_SWSUP_SIDLE) ?
  			HWMOD_IDLEMODE_NO : HWMOD_IDLEMODE_SMART;
  		_set_slave_idlemode(oh, idlemode, &v);
  	}
  
  	if (sf & SYSC_HAS_MIDLEMODE) {
  		idlemode = (oh->flags & HWMOD_SWSUP_MSTANDBY) ?
  			HWMOD_IDLEMODE_NO : HWMOD_IDLEMODE_SMART;
  		_set_master_standbymode(oh, idlemode, &v);
  	}
  
  	if (sf & SYSC_HAS_AUTOIDLE) {
  		idlemode = (oh->flags & HWMOD_NO_OCP_AUTOIDLE) ?
  			0 : 1;
  		_set_module_autoidle(oh, idlemode, &v);
  	}
  
  	/* XXX OCP ENAWAKEUP bit? */
  
  	/*
  	 * 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);
  }
  
  /**
   * _sysc_idle - 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 _sysc_idle(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) {
  		idlemode = (oh->flags & HWMOD_SWSUP_SIDLE) ?
  			HWMOD_IDLEMODE_FORCE : HWMOD_IDLEMODE_SMART;
  		_set_slave_idlemode(oh, idlemode, &v);
  	}
  
  	if (sf & SYSC_HAS_MIDLEMODE) {
  		idlemode = (oh->flags & HWMOD_SWSUP_MSTANDBY) ?
  			HWMOD_IDLEMODE_FORCE : HWMOD_IDLEMODE_SMART;
  		_set_master_standbymode(oh, idlemode, &v);
  	}
  
  	_write_sysconfig(v, oh);
  }
  
  /**
   * _sysc_shutdown - 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 _sysc_shutdown(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.
   * Caller must hold omap_hwmod_mutex.
   */
  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_clocks - clk_get() all clocks associated with this hwmod
   * @oh: struct omap_hwmod *
   *
   * Called by omap_hwmod_late_init() (after omap2_clk_init()).
   * Resolves all clock names embedded in the hwmod.  Must be called
   * with omap_hwmod_mutex held.  Returns -EINVAL if the omap_hwmod
   * has not yet been registered or if the clocks have already been
   * initialized, 0 on success, or a non-zero error on failure.
   */
  static int _init_clocks(struct omap_hwmod *oh)
  {
  	int ret = 0;
  
  	if (!oh || (oh->_state != _HWMOD_STATE_REGISTERED))
  		return -EINVAL;
  
  	pr_debug("omap_hwmod: %s: looking up clocks\n", oh->name);
  
  	ret |= _init_main_clk(oh);
  	ret |= _init_interface_clks(oh);
  	ret |= _init_opt_clks(oh);
  
  	if (!ret)
  		oh->_state = _HWMOD_STATE_CLKS_INITED;
  
  	return 0;
  }
  
  /**
   * _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 _wait_target_ready(struct omap_hwmod *oh)
  {
  	struct omap_hwmod_ocp_if *os;
  	int ret;
  
  	if (!oh)
  		return -EINVAL;
  
  	if (oh->_int_flags & _HWMOD_NO_MPU_PORT)
  		return 0;
  
  	os = oh->slaves[oh->_mpu_port_index];
  
  	if (oh->flags & HWMOD_NO_IDLEST)
  		return 0;
  
  	/* XXX check module SIDLEMODE */
  
  	/* XXX check clock enable states */
  
  	if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
  		ret = omap2_cm_wait_module_ready(oh->prcm.omap2.module_offs,
  						 oh->prcm.omap2.idlest_reg_id,
  						 oh->prcm.omap2.idlest_idle_bit);
  	} else if (cpu_is_omap44xx()) {
  		ret = omap4_cm_wait_module_ready(oh->prcm.omap4.clkctrl_reg);
  	} else {
  		BUG();
  	};
  
  	return ret;
  }
  
  /**
   * _reset - reset an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Resets an omap_hwmod @oh via the OCP_SYSCONFIG bit.  hwmod must be
   * enabled for this to work.  Must be called with omap_hwmod_mutex
   * held.  Returns -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)
  {
  	u32 r, v;
  	int c = 0;
  
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_SOFTRESET) ||
  	    (oh->class->sysc->sysc_flags & SYSS_MISSING))
  		return -EINVAL;
  
  	/* clocks must be on for this operation */
  	if (oh->_state != _HWMOD_STATE_ENABLED) {
  		WARN(1, "omap_hwmod: %s: reset can only be entered from "
  		     "enabled state\n", oh->name);
  		return -EINVAL;
  	}
  
  	pr_debug("omap_hwmod: %s: resetting\n", oh->name);
  
  	v = oh->_sysc_cache;
  	r = _set_softreset(oh, &v);
  	if (r)
  		return r;
  	_write_sysconfig(v, oh);
  
  	omap_test_timeout((omap_hwmod_readl(oh, oh->class->sysc->syss_offs) &
  			   SYSS_RESETDONE_MASK),
  			  MAX_MODULE_RESET_WAIT, c);
  
  	if (c == MAX_MODULE_RESET_WAIT)
  		WARN(1, "omap_hwmod: %s: failed to reset in %d usec\n",
  		     oh->name, MAX_MODULE_RESET_WAIT);
  	else
  		pr_debug("omap_hwmod: %s: reset 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()
  	 */
  
  	return (c == MAX_MODULE_RESET_WAIT) ? -ETIMEDOUT : 0;
  }
  
  /**
   * _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.  Must be called with omap_hwmod_mutex held.
   * 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;
  
  	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;
  	}
  
  	pr_debug("omap_hwmod: %s: enabling\n", oh->name);
  
  	/* XXX mux balls */
  
  	_add_initiator_dep(oh, mpu_oh);
  	_enable_clocks(oh);
  
  	r = _wait_target_ready(oh);
  	if (!r) {
  		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);
  			_sysc_enable(oh);
  		}
  	} else {
  		pr_debug("omap_hwmod: %s: _wait_target_ready: %d\n",
  			 oh->name, r);
  	}
  
  	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)
  {
  	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;
  	}
  
  	pr_debug("omap_hwmod: %s: idling\n", oh->name);
  
  	if (oh->class->sysc)
  		_sysc_idle(oh);
  	_del_initiator_dep(oh, mpu_oh);
  	_disable_clocks(oh);
  
  	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)
  {
  	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;
  	}
  
  	pr_debug("omap_hwmod: %s: disabling\n", oh->name);
  
  	if (oh->class->sysc)
  		_sysc_shutdown(oh);
  	_del_initiator_dep(oh, mpu_oh);
  	/* XXX what about the other system initiators here? DMA, tesla, d2d */
  	_disable_clocks(oh);
  	/* XXX Should this code also force-disable the optional clocks? */
  
  	/* XXX mux any associated balls to safe mode */
  
  	oh->_state = _HWMOD_STATE_DISABLED;
  
  	return 0;
  }
  
  /**
   * _setup - do initial configuration of omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Writes the CLOCKACTIVITY bits @clockact to the hwmod @oh
   * OCP_SYSCONFIG register.  Must be called with omap_hwmod_mutex
   * held.  Returns -EINVAL if the hwmod is in the wrong state or returns
   * 0.
   */
  static int _setup(struct omap_hwmod *oh)
  {
  	int i, r;
  
  	if (!oh)
  		return -EINVAL;
  
  	/* Set iclk autoidle mode */
  	if (oh->slaves_cnt > 0) {
  		for (i = 0; i < oh->slaves_cnt; i++) {
  			struct omap_hwmod_ocp_if *os = oh->slaves[i];
  			struct clk *c = os->_clk;
  
  			if (!c)
  				continue;
  
  			if (os->flags & OCPIF_SWSUP_IDLE) {
  				/* XXX omap_iclk_deny_idle(c); */
  			} else {
  				/* XXX omap_iclk_allow_idle(c); */
  				clk_enable(c);
  			}
  		}
  	}
  
  	oh->_state = _HWMOD_STATE_INITIALIZED;
  
  	r = _enable(oh);
  	if (r) {
  		pr_warning("omap_hwmod: %s: cannot be enabled (%d)\n",
  			   oh->name, oh->_state);
  		return 0;
  	}
  
  	if (!(oh->flags & HWMOD_INIT_NO_RESET)) {
  		/*
  		 * XXX Do the OCP_SYSCONFIG bits need to be
  		 * reprogrammed after a reset?  If not, then this can
  		 * be removed.  If they do, then probably the
  		 * _enable() function should be split to avoid the
  		 * rewrite of the OCP_SYSCONFIG register.
  		 */
  		if (oh->class->sysc) {
  			_update_sysc_cache(oh);
  			_sysc_enable(oh);
  		}
  	}
  
  	if (!(oh->flags & HWMOD_INIT_NO_IDLE))
  		_idle(oh);
  
  	return 0;
  }
  
  
  
  /* Public functions */
  
  u32 omap_hwmod_readl(struct omap_hwmod *oh, u16 reg_offs)
  {
  	return __raw_readl(oh->_rt_va + reg_offs);
  }
  
  void omap_hwmod_writel(u32 v, struct omap_hwmod *oh, u16 reg_offs)
  {
  	__raw_writel(v, oh->_rt_va + reg_offs);
  }
  
  int omap_hwmod_set_slave_idlemode(struct omap_hwmod *oh, u8 idlemode)
  {
  	u32 v;
  	int retval = 0;
  
  	if (!oh)
  		return -EINVAL;
  
  	v = oh->_sysc_cache;
  
  	retval = _set_slave_idlemode(oh, idlemode, &v);
  	if (!retval)
  		_write_sysconfig(v, oh);
  
  	return retval;
  }
  
  /**
   * omap_hwmod_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.
   */
  int omap_hwmod_register(struct omap_hwmod *oh)
  {
  	int ret, ms_id;
  
  	if (!oh || !oh->name || !oh->class || !oh->class->name ||
  	    (oh->_state != _HWMOD_STATE_UNKNOWN))
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  
  	pr_debug("omap_hwmod: %s: registering\n", oh->name);
  
  	if (_lookup(oh->name)) {
  		ret = -EEXIST;
  		goto ohr_unlock;
  	}
  
  	ms_id = _find_mpu_port_index(oh);
  	if (!IS_ERR_VALUE(ms_id)) {
  		oh->_mpu_port_index = ms_id;
  		oh->_rt_va = _find_mpu_rt_base(oh, oh->_mpu_port_index);
  	} else {
  		oh->_int_flags |= _HWMOD_NO_MPU_PORT;
  	}
  
  	list_add_tail(&oh->node, &omap_hwmod_list);
  
  	oh->_state = _HWMOD_STATE_REGISTERED;
  
  	ret = 0;
  
  ohr_unlock:
  	mutex_unlock(&omap_hwmod_mutex);
  	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;
  
  	mutex_lock(&omap_hwmod_mutex);
  	oh = _lookup(name);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	return oh;
  }
  
  /**
   * omap_hwmod_for_each - call function for each registered omap_hwmod
   * @fn: pointer to a 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))
  {
  	struct omap_hwmod *temp_oh;
  	int ret;
  
  	if (!fn)
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  	list_for_each_entry(temp_oh, &omap_hwmod_list, node) {
  		ret = (*fn)(temp_oh);
  		if (ret)
  			break;
  	}
  	mutex_unlock(&omap_hwmod_mutex);
  
  	return ret;
  }
  
  
  /**
   * omap_hwmod_init - init omap_hwmod code and register hwmods
   * @ohs: pointer to an array of omap_hwmods to register
   *
   * Intended to be called early in boot before the clock framework is
   * initialized.  If @ohs is not null, will register all omap_hwmods
   * listed in @ohs that are valid for this chip.  Returns -EINVAL if
   * omap_hwmod_init() has already been called or 0 otherwise.
   */
  int omap_hwmod_init(struct omap_hwmod **ohs)
  {
  	struct omap_hwmod *oh;
  	int r;
  
  	if (inited)
  		return -EINVAL;
  
  	inited = 1;
  
  	if (!ohs)
  		return 0;
  
  	oh = *ohs;
  	while (oh) {
  		if (omap_chip_is(oh->omap_chip)) {
  			r = omap_hwmod_register(oh);
  			WARN(r, "omap_hwmod: %s: omap_hwmod_register returned "
  			     "%d\n", oh->name, r);
  		}
  		oh = *++ohs;
  	}
  
  	return 0;
  }
  
  /**
   * omap_hwmod_late_init - do some post-clock framework initialization
   *
   * 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.
   */
  int omap_hwmod_late_init(void)
  {
  	int r;
  
  	/* XXX check return value */
  	r = omap_hwmod_for_each(_init_clocks);
  	WARN(r, "omap_hwmod: omap_hwmod_late_init(): _init_clocks failed\n");
  
  	mpu_oh = omap_hwmod_lookup(MPU_INITIATOR_NAME);
  	WARN(!mpu_oh, "omap_hwmod: could not find MPU initiator hwmod %s\n",
  	     MPU_INITIATOR_NAME);
  
  	omap_hwmod_for_each(_setup);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_unregister - unregister an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Unregisters a previously-registered omap_hwmod @oh.  There's probably
   * no use case for this, so it is likely to be removed in a later version.
   *
   * XXX Free all of the bootmem-allocated structures here when that is
   * implemented.  Make it clear that core code is the only code that is
   * expected to unregister modules.
   */
  int omap_hwmod_unregister(struct omap_hwmod *oh)
  {
  	if (!oh)
  		return -EINVAL;
  
  	pr_debug("omap_hwmod: %s: unregistering\n", oh->name);
  
  	mutex_lock(&omap_hwmod_mutex);
  	iounmap(oh->_rt_va);
  	list_del(&oh->node);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_enable - enable an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Enable an omap_hwomd @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;
  
  	if (!oh)
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  	r = _enable(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	return r;
  }
  
  /**
   * omap_hwmod_idle - idle an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Idle an omap_hwomd @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)
  {
  	if (!oh)
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  	_idle(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	return 0;
  }
  
  /**
   * omap_hwmod_shutdown - shutdown an omap_hwmod
   * @oh: struct omap_hwmod *
   *
   * Shutdown an omap_hwomd @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)
  {
  	if (!oh)
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  	_shutdown(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	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)
  {
  	mutex_lock(&omap_hwmod_mutex);
  	_enable_clocks(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	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)
  {
  	mutex_lock(&omap_hwmod_mutex);
  	_disable_clocks(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	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_readl(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()/_enable().
   */
  int omap_hwmod_reset(struct omap_hwmod *oh)
  {
  	int r;
  
  	if (!oh || !(oh->_state & _HWMOD_STATE_ENABLED))
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  	r = _reset(oh);
  	if (!r)
  		r = _enable(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	return r;
  }
  
  /**
   * omap_hwmod_count_resources - count number of struct resources needed by hwmod
   * @oh: struct omap_hwmod *
   * @res: pointer to the first element of an array of struct resource to fill
   *
   * 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)
  {
  	int ret, i;
  
  	ret = oh->mpu_irqs_cnt + oh->sdma_chs_cnt;
  
  	for (i = 0; i < oh->slaves_cnt; i++)
  		ret += oh->slaves[i]->addr_cnt;
  
  	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)
  {
  	int i, j;
  	int r = 0;
  
  	/* For each IRQ, DMA, memory area, fill in array.*/
  
  	for (i = 0; i < oh->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++;
  	}
  
  	for (i = 0; i < oh->sdma_chs_cnt; i++) {
  		(res + r)->name = (oh->sdma_chs + i)->name;
  		(res + r)->start = (oh->sdma_chs + i)->dma_ch;
  		(res + r)->end = (oh->sdma_chs + i)->dma_ch;
  		(res + r)->flags = IORESOURCE_DMA;
  		r++;
  	}
  
  	for (i = 0; i < oh->slaves_cnt; i++) {
  		struct omap_hwmod_ocp_if *os;
  
  		os = oh->slaves[i];
  
  		for (j = 0; j < os->addr_cnt; j++) {
  			(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_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;
  
  	if (!oh)
  		return NULL;
  
  	if (oh->_clk) {
  		c = oh->_clk;
  	} else {
  		if (oh->_int_flags & _HWMOD_NO_MPU_PORT)
  			return NULL;
  		c = oh->slaves[oh->_mpu_port_index]->_clk;
  	}
  
  	if (!c->clkdm)
  		return NULL;
  
  	return c->clkdm->pwrdm.ptr;
  
  }
  
  /**
   * 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.  Eventually this should sets 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)
  {
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  	_enable_wakeup(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	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.  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)
  {
  	if (!oh->class->sysc ||
  	    !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
  		return -EINVAL;
  
  	mutex_lock(&omap_hwmod_mutex);
  	_disable_wakeup(oh);
  	mutex_unlock(&omap_hwmod_mutex);
  
  	return 0;
  }
  
  /**
   * 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.  Takes
   * omap_hwmod_mutex to prevent the hwmod list from changing during the
   * iteration.  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);
  
  	mutex_lock(&omap_hwmod_mutex);
  
  	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;
  		}
  	}
  
  	mutex_unlock(&omap_hwmod_mutex);
  
  	if (ret)
  		pr_debug("omap_hwmod: %s: iterator terminated early: %d\n",
  			 __func__, ret);
  
  	return ret;
  }
  
  