text: /*
   * Broadcom SPI Host Controller Driver - Linux Per-port
   *
   * Copyright (C) 1999-2014, Broadcom Corporation
   * 
   *      Unless you and Broadcom execute a separate written software license
   * agreement governing use of this software, this software is licensed to you
   * under the terms of the GNU General Public License version 2 (the "GPL"),
   * available at http://www.broadcom.com/licenses/GPLv2.php, with the
   * following added to such license:
   * 
   *      As a special exception, the copyright holders of this software give you
   * permission to link this software with independent modules, and to copy and
   * distribute the resulting executable under terms of your choice, provided that
   * you also meet, for each linked independent module, the terms and conditions of
   * the license of that module.  An independent module is a module which is not
   * derived from this software.  The special exception does not apply to any
   * modifications of the software.
   * 
   *      Notwithstanding the above, under no circumstances may you combine this
   * software in any way with any other Broadcom software provided under a license
   * other than the GPL, without Broadcom's express prior written consent.
   *
   * $Id: bcmsdspi_linux.c 406045 2013-06-05 22:09:52Z $
   */
  
  #include <typedefs.h>
  #include <bcmutils.h>
  
  #include <bcmsdbus.h>		/* bcmsdh to/from specific controller APIs */
  #include <sdiovar.h>		/* to get msglevel bit values */
  
  #include <pcicfg.h>
  #include <sdio.h>		/* SDIO Device and Protocol Specs */
  #include <linux/sched.h>	/* request_irq(), free_irq() */
  #include <bcmsdspi.h>
  #include <bcmspi.h>
  
  extern uint sd_crc;
  module_param(sd_crc, uint, 0);
  
  #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0))
  #define KERNEL26
  #endif
  
  struct sdos_info {
  	sdioh_info_t *sd;
  	spinlock_t lock;
  	wait_queue_head_t intr_wait_queue;
  };
  
  #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0))
  #define BLOCKABLE()	(!in_atomic())
  #else
  #define BLOCKABLE()	(!in_interrupt())
  #endif
  
  /* Interrupt handler */
  static irqreturn_t
  sdspi_isr(int irq, void *dev_id
  #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20)
  , struct pt_regs *ptregs
  #endif
  )
  {
  	sdioh_info_t *sd;
  	struct sdos_info *sdos;
  	bool ours;
  
  	sd = (sdioh_info_t *)dev_id;
  	sd->local_intrcount++;
  
  	if (!sd->card_init_done) {
  		sd_err(("%s: Hey Bogus intr...not even initted: irq %d\n", __FUNCTION__, irq));
  		return IRQ_RETVAL(FALSE);
  	} else {
  		ours = spi_check_client_intr(sd, NULL);
  
  		/* For local interrupts, wake the waiting process */
  		if (ours && sd->got_hcint) {
  			sdos = (struct sdos_info *)sd->sdos_info;
  			wake_up_interruptible(&sdos->intr_wait_queue);
  		}
  
  		return IRQ_RETVAL(ours);
  	}
  }
  
  
  /* Register with Linux for interrupts */
  int
  spi_register_irq(sdioh_info_t *sd, uint irq)
  {
  	sd_trace(("Entering %s: irq == %d\n", __FUNCTION__, irq));
  	if (request_irq(irq, sdspi_isr, IRQF_SHARED, "bcmsdspi", sd) < 0) {
  		sd_err(("%s: request_irq() failed\n", __FUNCTION__));
  		return ERROR;
  	}
  	return SUCCESS;
  }
  
  /* Free Linux irq */
  void
  spi_free_irq(uint irq, sdioh_info_t *sd)
  {
  	free_irq(irq, sd);
  }
  
  /* Map Host controller registers */
  uint32 *
  spi_reg_map(osl_t *osh, uintptr addr, int size)
  {
  	return (uint32 *)REG_MAP(addr, size);
  }
  
  void
  spi_reg_unmap(osl_t *osh, uintptr addr, int size)
  {
  	REG_UNMAP((void*)(uintptr)addr);
  }
  
  int
  spi_osinit(sdioh_info_t *sd)
  {
  	struct sdos_info *sdos;
  
  	sdos = (struct sdos_info*)MALLOC(sd->osh, sizeof(struct sdos_info));
  	sd->sdos_info = (void*)sdos;
  	if (sdos == NULL)
  		return BCME_NOMEM;
  
  	sdos->sd = sd;
  	spin_lock_init(&sdos->lock);
  	init_waitqueue_head(&sdos->intr_wait_queue);
  	return BCME_OK;
  }
  
  void
  spi_osfree(sdioh_info_t *sd)
  {
  	struct sdos_info *sdos;
  	ASSERT(sd && sd->sdos_info);
  
  	sdos = (struct sdos_info *)sd->sdos_info;
  	MFREE(sd->osh, sdos, sizeof(struct sdos_info));
  }
  
  /* Interrupt enable/disable */
  SDIOH_API_RC
  sdioh_interrupt_set(sdioh_info_t *sd, bool enable)
  {
  	ulong flags;
  	struct sdos_info *sdos;
  
  	sd_trace(("%s: %s\n", __FUNCTION__, enable ? "Enabling" : "Disabling"));
  
  	sdos = (struct sdos_info *)sd->sdos_info;
  	ASSERT(sdos);
  
  	if (!(sd->host_init_done && sd->card_init_done)) {
  		sd_err(("%s: Card & Host are not initted - bailing\n", __FUNCTION__));
  		return SDIOH_API_RC_FAIL;
  	}
  
  	if (enable && !(sd->intr_handler && sd->intr_handler_arg)) {
  		sd_err(("%s: no handler registered, will not enable\n", __FUNCTION__));
  		return SDIOH_API_RC_FAIL;
  	}
  
  	/* Ensure atomicity for enable/disable calls */
  	spin_lock_irqsave(&sdos->lock, flags);
  
  	sd->client_intr_enabled = enable;
  	if (enable && !sd->lockcount)
  		spi_devintr_on(sd);
  	else
  		spi_devintr_off(sd);
  
  	spin_unlock_irqrestore(&sdos->lock, flags);
  
  	return SDIOH_API_RC_SUCCESS;
  }
  
  /* Protect against reentrancy (disable device interrupts while executing) */
  void
  spi_lock(sdioh_info_t *sd)
  {
  	ulong flags;
  	struct sdos_info *sdos;
  
  	sdos = (struct sdos_info *)sd->sdos_info;
  	ASSERT(sdos);
  
  	sd_trace(("%s: %d\n", __FUNCTION__, sd->lockcount));
  
  	spin_lock_irqsave(&sdos->lock, flags);
  	if (sd->lockcount) {
  		sd_err(("%s: Already locked!\n", __FUNCTION__));
  		ASSERT(sd->lockcount == 0);
  	}
  	spi_devintr_off(sd);
  	sd->lockcount++;
  	spin_unlock_irqrestore(&sdos->lock, flags);
  }
  
  /* Enable client interrupt */
  void
  spi_unlock(sdioh_info_t *sd)
  {
  	ulong flags;
  	struct sdos_info *sdos;
  
  	sd_trace(("%s: %d, %d\n", __FUNCTION__, sd->lockcount, sd->client_intr_enabled));
  	ASSERT(sd->lockcount > 0);
  
  	sdos = (struct sdos_info *)sd->sdos_info;
  	ASSERT(sdos);
  
  	spin_lock_irqsave(&sdos->lock, flags);
  	if (--sd->lockcount == 0 && sd->client_intr_enabled) {
  		spi_devintr_on(sd);
  	}
  	spin_unlock_irqrestore(&sdos->lock, flags);
  }
  
  void spi_waitbits(sdioh_info_t *sd, bool yield)
  {
  #ifndef BCMSDYIELD
  	ASSERT(!yield);
  #endif
  	sd_trace(("%s: yield %d canblock %d\n",
  	          __FUNCTION__, yield, BLOCKABLE()));
  
  	/* Clear the "interrupt happened" flag and last intrstatus */
  	sd->got_hcint = FALSE;
  
  #ifdef BCMSDYIELD
  	if (yield && BLOCKABLE()) {
  		struct sdos_info *sdos;
  		sdos = (struct sdos_info *)sd->sdos_info;
  		/* Wait for the indication, the interrupt will be masked when the ISR fires. */
  		wait_event_interruptible(sdos->intr_wait_queue, (sd->got_hcint));
  	} else
  #endif /* BCMSDYIELD */
  	{
  		spi_spinbits(sd);
  	}
  
  }
  