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Commit d02bf062 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'spi/next' of git://git.secretlab.ca/git/linux-2.6 

* 'spi/next' of git://git.secretlab.ca/git/linux-2.6:
  spi/spi_bfin_sport: new driver for a SPI bus via the Blackfin SPORT peripheral
  spi/tle620x: add missing device_remove_file()
parents 04830fcc 9c3e7375

drivers/spi/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -80,6 +80,15 @@ config SPI_BFIN 
	help

	  This is the SPI controller master driver for Blackfin 5xx processor.



config SPI_BFIN_SPORT

	tristate "SPI bus via Blackfin SPORT"

	depends on BLACKFIN

	help

	  Enable support for a SPI bus via the Blackfin SPORT peripheral.



	  This driver can also be built as a module.  If so, the module

	  will be called spi_bfin_sport.



config SPI_AU1550

	tristate "Au1550/Au12x0 SPI Controller"

	depends on (SOC_AU1550 || SOC_AU1200) && EXPERIMENTAL

drivers/spi/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ obj-$(CONFIG_SPI_ALTERA) += spi_altera.o 
obj-$(CONFIG_SPI_ATMEL)			+= atmel_spi.o

obj-$(CONFIG_SPI_ATH79)			+= ath79_spi.o

obj-$(CONFIG_SPI_BFIN)			+= spi_bfin5xx.o

obj-$(CONFIG_SPI_BFIN_SPORT)		+= spi_bfin_sport.o

obj-$(CONFIG_SPI_BITBANG)		+= spi_bitbang.o

obj-$(CONFIG_SPI_AU1550)		+= au1550_spi.o

obj-$(CONFIG_SPI_BUTTERFLY)		+= spi_butterfly.o

drivers/spi/spi_bfin_sport.c

0 → 100644
+952 −0
Original line number Diff line number Diff line 
/*

 * SPI bus via the Blackfin SPORT peripheral

 *

 * Enter bugs at http://blackfin.uclinux.org/

 *

 * Copyright 2009-2011 Analog Devices Inc.

 *

 * Licensed under the GPL-2 or later.

 */



#include <linux/init.h>

#include <linux/module.h>

#include <linux/delay.h>

#include <linux/device.h>

#include <linux/gpio.h>

#include <linux/io.h>

#include <linux/ioport.h>

#include <linux/irq.h>

#include <linux/errno.h>

#include <linux/interrupt.h>

#include <linux/platform_device.h>

#include <linux/spi/spi.h>

#include <linux/workqueue.h>



#include <asm/portmux.h>

#include <asm/bfin5xx_spi.h>

#include <asm/blackfin.h>

#include <asm/bfin_sport.h>

#include <asm/cacheflush.h>



#define DRV_NAME	"bfin-sport-spi"

#define DRV_DESC	"SPI bus via the Blackfin SPORT"



MODULE_AUTHOR("Cliff Cai");

MODULE_DESCRIPTION(DRV_DESC);

MODULE_LICENSE("GPL");

MODULE_ALIAS("platform:bfin-sport-spi");



enum bfin_sport_spi_state {

	START_STATE,

	RUNNING_STATE,

	DONE_STATE,

	ERROR_STATE,

};



struct bfin_sport_spi_master_data;



struct bfin_sport_transfer_ops {

	void (*write) (struct bfin_sport_spi_master_data *);

	void (*read) (struct bfin_sport_spi_master_data *);

	void (*duplex) (struct bfin_sport_spi_master_data *);

};



struct bfin_sport_spi_master_data {

	/* Driver model hookup */

	struct device *dev;



	/* SPI framework hookup */

	struct spi_master *master;



	/* Regs base of SPI controller */

	struct sport_register __iomem *regs;

	int err_irq;



	/* Pin request list */

	u16 *pin_req;



	/* Driver message queue */

	struct workqueue_struct *workqueue;

	struct work_struct pump_messages;

	spinlock_t lock;

	struct list_head queue;

	int busy;

	bool run;



	/* Message Transfer pump */

	struct tasklet_struct pump_transfers;



	/* Current message transfer state info */

	enum bfin_sport_spi_state state;

	struct spi_message *cur_msg;

	struct spi_transfer *cur_transfer;

	struct bfin_sport_spi_slave_data *cur_chip;

	union {

		void *tx;

		u8 *tx8;

		u16 *tx16;

	};

	void *tx_end;

	union {

		void *rx;

		u8 *rx8;

		u16 *rx16;

	};

	void *rx_end;



	int cs_change;

	struct bfin_sport_transfer_ops *ops;

};



struct bfin_sport_spi_slave_data {

	u16 ctl_reg;

	u16 baud;

	u16 cs_chg_udelay;	/* Some devices require > 255usec delay */

	u32 cs_gpio;

	u16 idle_tx_val;

	struct bfin_sport_transfer_ops *ops;

};



static void

bfin_sport_spi_enable(struct bfin_sport_spi_master_data *drv_data)

{

	bfin_write_or(&drv_data->regs->tcr1, TSPEN);

	bfin_write_or(&drv_data->regs->rcr1, TSPEN);

	SSYNC();

}



static void

bfin_sport_spi_disable(struct bfin_sport_spi_master_data *drv_data)

{

	bfin_write_and(&drv_data->regs->tcr1, ~TSPEN);

	bfin_write_and(&drv_data->regs->rcr1, ~TSPEN);

	SSYNC();

}



/* Caculate the SPI_BAUD register value based on input HZ */

static u16

bfin_sport_hz_to_spi_baud(u32 speed_hz)

{

	u_long clk, sclk = get_sclk();

	int div = (sclk / (2 * speed_hz)) - 1;



	if (div < 0)

		div = 0;



	clk = sclk / (2 * (div + 1));



	if (clk > speed_hz)

		div++;



	return div;

}



/* Chip select operation functions for cs_change flag */

static void

bfin_sport_spi_cs_active(struct bfin_sport_spi_slave_data *chip)

{

	gpio_direction_output(chip->cs_gpio, 0);

}



static void

bfin_sport_spi_cs_deactive(struct bfin_sport_spi_slave_data *chip)

{

	gpio_direction_output(chip->cs_gpio, 1);

	/* Move delay here for consistency */

	if (chip->cs_chg_udelay)

		udelay(chip->cs_chg_udelay);

}



static void

bfin_sport_spi_stat_poll_complete(struct bfin_sport_spi_master_data *drv_data)

{

	unsigned long timeout = jiffies + HZ;

	while (!(bfin_read(&drv_data->regs->stat) & RXNE)) {

		if (!time_before(jiffies, timeout))

			break;

	}

}



static void

bfin_sport_spi_u8_writer(struct bfin_sport_spi_master_data *drv_data)

{

	u16 dummy;



	while (drv_data->tx < drv_data->tx_end) {

		bfin_write(&drv_data->regs->tx16, *drv_data->tx8++);

		bfin_sport_spi_stat_poll_complete(drv_data);

		dummy = bfin_read(&drv_data->regs->rx16);

	}

}



static void

bfin_sport_spi_u8_reader(struct bfin_sport_spi_master_data *drv_data)

{

	u16 tx_val = drv_data->cur_chip->idle_tx_val;



	while (drv_data->rx < drv_data->rx_end) {

		bfin_write(&drv_data->regs->tx16, tx_val);

		bfin_sport_spi_stat_poll_complete(drv_data);

		*drv_data->rx8++ = bfin_read(&drv_data->regs->rx16);

	}

}



static void

bfin_sport_spi_u8_duplex(struct bfin_sport_spi_master_data *drv_data)

{

	while (drv_data->rx < drv_data->rx_end) {

		bfin_write(&drv_data->regs->tx16, *drv_data->tx8++);

		bfin_sport_spi_stat_poll_complete(drv_data);

		*drv_data->rx8++ = bfin_read(&drv_data->regs->rx16);

	}

}



static struct bfin_sport_transfer_ops bfin_sport_transfer_ops_u8 = {

	.write  = bfin_sport_spi_u8_writer,

	.read   = bfin_sport_spi_u8_reader,

	.duplex = bfin_sport_spi_u8_duplex,

};



static void

bfin_sport_spi_u16_writer(struct bfin_sport_spi_master_data *drv_data)

{

	u16 dummy;



	while (drv_data->tx < drv_data->tx_end) {

		bfin_write(&drv_data->regs->tx16, *drv_data->tx16++);

		bfin_sport_spi_stat_poll_complete(drv_data);

		dummy = bfin_read(&drv_data->regs->rx16);

	}

}



static void

bfin_sport_spi_u16_reader(struct bfin_sport_spi_master_data *drv_data)

{

	u16 tx_val = drv_data->cur_chip->idle_tx_val;



	while (drv_data->rx < drv_data->rx_end) {

		bfin_write(&drv_data->regs->tx16, tx_val);

		bfin_sport_spi_stat_poll_complete(drv_data);

		*drv_data->rx16++ = bfin_read(&drv_data->regs->rx16);

	}

}



static void

bfin_sport_spi_u16_duplex(struct bfin_sport_spi_master_data *drv_data)

{

	while (drv_data->rx < drv_data->rx_end) {

		bfin_write(&drv_data->regs->tx16, *drv_data->tx16++);

		bfin_sport_spi_stat_poll_complete(drv_data);

		*drv_data->rx16++ = bfin_read(&drv_data->regs->rx16);

	}

}



static struct bfin_sport_transfer_ops bfin_sport_transfer_ops_u16 = {

	.write  = bfin_sport_spi_u16_writer,

	.read   = bfin_sport_spi_u16_reader,

	.duplex = bfin_sport_spi_u16_duplex,

};



/* stop controller and re-config current chip */

static void

bfin_sport_spi_restore_state(struct bfin_sport_spi_master_data *drv_data)

{

	struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip;

	unsigned int bits = (drv_data->ops == &bfin_sport_transfer_ops_u8 ? 7 : 15);



	bfin_sport_spi_disable(drv_data);

	dev_dbg(drv_data->dev, "restoring spi ctl state\n");



	bfin_write(&drv_data->regs->tcr1, chip->ctl_reg);

	bfin_write(&drv_data->regs->tcr2, bits);

	bfin_write(&drv_data->regs->tclkdiv, chip->baud);

	bfin_write(&drv_data->regs->tfsdiv, bits);

	SSYNC();



	bfin_write(&drv_data->regs->rcr1, chip->ctl_reg & ~(ITCLK | ITFS));

	bfin_write(&drv_data->regs->rcr2, bits);

	SSYNC();



	bfin_sport_spi_cs_active(chip);

}



/* test if there is more transfer to be done */

static enum bfin_sport_spi_state

bfin_sport_spi_next_transfer(struct bfin_sport_spi_master_data *drv_data)

{

	struct spi_message *msg = drv_data->cur_msg;

	struct spi_transfer *trans = drv_data->cur_transfer;



	/* Move to next transfer */

	if (trans->transfer_list.next != &msg->transfers) {

		drv_data->cur_transfer =

		    list_entry(trans->transfer_list.next,

			       struct spi_transfer, transfer_list);

		return RUNNING_STATE;

	}



	return DONE_STATE;

}



/*

 * caller already set message->status;

 * dma and pio irqs are blocked give finished message back

 */

static void

bfin_sport_spi_giveback(struct bfin_sport_spi_master_data *drv_data)

{

	struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip;

	unsigned long flags;

	struct spi_message *msg;



	spin_lock_irqsave(&drv_data->lock, flags);

	msg = drv_data->cur_msg;

	drv_data->state = START_STATE;

	drv_data->cur_msg = NULL;

	drv_data->cur_transfer = NULL;

	drv_data->cur_chip = NULL;

	queue_work(drv_data->workqueue, &drv_data->pump_messages);

	spin_unlock_irqrestore(&drv_data->lock, flags);



	if (!drv_data->cs_change)

		bfin_sport_spi_cs_deactive(chip);



	if (msg->complete)

		msg->complete(msg->context);

}



static irqreturn_t

sport_err_handler(int irq, void *dev_id)

{

	struct bfin_sport_spi_master_data *drv_data = dev_id;

	u16 status;



	dev_dbg(drv_data->dev, "%s enter\n", __func__);

	status = bfin_read(&drv_data->regs->stat) & (TOVF | TUVF | ROVF | RUVF);



	if (status) {

		bfin_write(&drv_data->regs->stat, status);

		SSYNC();



		bfin_sport_spi_disable(drv_data);

		dev_err(drv_data->dev, "status error:%s%s%s%s\n",

			status & TOVF ? " TOVF" : "",

			status & TUVF ? " TUVF" : "",

			status & ROVF ? " ROVF" : "",

			status & RUVF ? " RUVF" : "");

	}



	return IRQ_HANDLED;

}



static void

bfin_sport_spi_pump_transfers(unsigned long data)

{

	struct bfin_sport_spi_master_data *drv_data = (void *)data;

	struct spi_message *message = NULL;

	struct spi_transfer *transfer = NULL;

	struct spi_transfer *previous = NULL;

	struct bfin_sport_spi_slave_data *chip = NULL;

	unsigned int bits_per_word;

	u32 tranf_success = 1;

	u32 transfer_speed;

	u8 full_duplex = 0;



	/* Get current state information */

	message = drv_data->cur_msg;

	transfer = drv_data->cur_transfer;

	chip = drv_data->cur_chip;



	if (transfer->speed_hz)

		transfer_speed = bfin_sport_hz_to_spi_baud(transfer->speed_hz);

	else

		transfer_speed = chip->baud;

	bfin_write(&drv_data->regs->tclkdiv, transfer_speed);

	SSYNC();



	/*

	 * if msg is error or done, report it back using complete() callback

	 */



	 /* Handle for abort */

	if (drv_data->state == ERROR_STATE) {

		dev_dbg(drv_data->dev, "transfer: we've hit an error\n");

		message->status = -EIO;

		bfin_sport_spi_giveback(drv_data);

		return;

	}



	/* Handle end of message */

	if (drv_data->state == DONE_STATE) {

		dev_dbg(drv_data->dev, "transfer: all done!\n");

		message->status = 0;

		bfin_sport_spi_giveback(drv_data);

		return;

	}



	/* Delay if requested at end of transfer */

	if (drv_data->state == RUNNING_STATE) {

		dev_dbg(drv_data->dev, "transfer: still running ...\n");

		previous = list_entry(transfer->transfer_list.prev,

				      struct spi_transfer, transfer_list);

		if (previous->delay_usecs)

			udelay(previous->delay_usecs);

	}



	if (transfer->len == 0) {

		/* Move to next transfer of this msg */

		drv_data->state = bfin_sport_spi_next_transfer(drv_data);

		/* Schedule next transfer tasklet */

		tasklet_schedule(&drv_data->pump_transfers);

	}



	if (transfer->tx_buf != NULL) {

		drv_data->tx = (void *)transfer->tx_buf;

		drv_data->tx_end = drv_data->tx + transfer->len;

		dev_dbg(drv_data->dev, "tx_buf is %p, tx_end is %p\n",

			transfer->tx_buf, drv_data->tx_end);

	} else

		drv_data->tx = NULL;



	if (transfer->rx_buf != NULL) {

		full_duplex = transfer->tx_buf != NULL;

		drv_data->rx = transfer->rx_buf;

		drv_data->rx_end = drv_data->rx + transfer->len;

		dev_dbg(drv_data->dev, "rx_buf is %p, rx_end is %p\n",

			transfer->rx_buf, drv_data->rx_end);

	} else

		drv_data->rx = NULL;



	drv_data->cs_change = transfer->cs_change;



	/* Bits per word setup */

	bits_per_word = transfer->bits_per_word ? : message->spi->bits_per_word;

	if (bits_per_word == 8)

		drv_data->ops = &bfin_sport_transfer_ops_u8;

	else

		drv_data->ops = &bfin_sport_transfer_ops_u16;



	drv_data->state = RUNNING_STATE;



	if (drv_data->cs_change)

		bfin_sport_spi_cs_active(chip);



	dev_dbg(drv_data->dev,

		"now pumping a transfer: width is %d, len is %d\n",

		bits_per_word, transfer->len);



	/* PIO mode write then read */

	dev_dbg(drv_data->dev, "doing IO transfer\n");



	bfin_sport_spi_enable(drv_data);

	if (full_duplex) {

		/* full duplex mode */

		BUG_ON((drv_data->tx_end - drv_data->tx) !=

		       (drv_data->rx_end - drv_data->rx));

		drv_data->ops->duplex(drv_data);



		if (drv_data->tx != drv_data->tx_end)

			tranf_success = 0;

	} else if (drv_data->tx != NULL) {

		/* write only half duplex */



		drv_data->ops->write(drv_data);



		if (drv_data->tx != drv_data->tx_end)

			tranf_success = 0;

	} else if (drv_data->rx != NULL) {

		/* read only half duplex */



		drv_data->ops->read(drv_data);

		if (drv_data->rx != drv_data->rx_end)

			tranf_success = 0;

	}

	bfin_sport_spi_disable(drv_data);



	if (!tranf_success) {

		dev_dbg(drv_data->dev, "IO write error!\n");

		drv_data->state = ERROR_STATE;

	} else {

		/* Update total byte transfered */

		message->actual_length += transfer->len;

		/* Move to next transfer of this msg */

		drv_data->state = bfin_sport_spi_next_transfer(drv_data);

		if (drv_data->cs_change)

			bfin_sport_spi_cs_deactive(chip);

	}



	/* Schedule next transfer tasklet */

	tasklet_schedule(&drv_data->pump_transfers);

}



/* pop a msg from queue and kick off real transfer */

static void

bfin_sport_spi_pump_messages(struct work_struct *work)

{

	struct bfin_sport_spi_master_data *drv_data;

	unsigned long flags;

	struct spi_message *next_msg;



	drv_data = container_of(work, struct bfin_sport_spi_master_data, pump_messages);



	/* Lock queue and check for queue work */

	spin_lock_irqsave(&drv_data->lock, flags);

	if (list_empty(&drv_data->queue) || !drv_data->run) {

		/* pumper kicked off but no work to do */

		drv_data->busy = 0;

		spin_unlock_irqrestore(&drv_data->lock, flags);

		return;

	}



	/* Make sure we are not already running a message */

	if (drv_data->cur_msg) {

		spin_unlock_irqrestore(&drv_data->lock, flags);

		return;

	}



	/* Extract head of queue */

	next_msg = list_entry(drv_data->queue.next,

		struct spi_message, queue);



	drv_data->cur_msg = next_msg;



	/* Setup the SSP using the per chip configuration */

	drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);



	list_del_init(&drv_data->cur_msg->queue);



	/* Initialize message state */

	drv_data->cur_msg->state = START_STATE;

	drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,

					    struct spi_transfer, transfer_list);

	bfin_sport_spi_restore_state(drv_data);

	dev_dbg(drv_data->dev, "got a message to pump, "

		"state is set to: baud %d, cs_gpio %i, ctl 0x%x\n",

		drv_data->cur_chip->baud, drv_data->cur_chip->cs_gpio,

		drv_data->cur_chip->ctl_reg);



	dev_dbg(drv_data->dev,

		"the first transfer len is %d\n",

		drv_data->cur_transfer->len);



	/* Mark as busy and launch transfers */

	tasklet_schedule(&drv_data->pump_transfers);



	drv_data->busy = 1;

	spin_unlock_irqrestore(&drv_data->lock, flags);

}



/*

 * got a msg to transfer, queue it in drv_data->queue.

 * And kick off message pumper

 */

static int

bfin_sport_spi_transfer(struct spi_device *spi, struct spi_message *msg)

{

	struct bfin_sport_spi_master_data *drv_data = spi_master_get_devdata(spi->master);

	unsigned long flags;



	spin_lock_irqsave(&drv_data->lock, flags);



	if (!drv_data->run) {

		spin_unlock_irqrestore(&drv_data->lock, flags);

		return -ESHUTDOWN;

	}



	msg->actual_length = 0;

	msg->status = -EINPROGRESS;

	msg->state = START_STATE;



	dev_dbg(&spi->dev, "adding an msg in transfer()\n");

	list_add_tail(&msg->queue, &drv_data->queue);



	if (drv_data->run && !drv_data->busy)

		queue_work(drv_data->workqueue, &drv_data->pump_messages);



	spin_unlock_irqrestore(&drv_data->lock, flags);



	return 0;

}



/* Called every time common spi devices change state */

static int

bfin_sport_spi_setup(struct spi_device *spi)

{

	struct bfin_sport_spi_slave_data *chip, *first = NULL;

	int ret;



	/* Only alloc (or use chip_info) on first setup */

	chip = spi_get_ctldata(spi);

	if (chip == NULL) {

		struct bfin5xx_spi_chip *chip_info;



		chip = first = kzalloc(sizeof(*chip), GFP_KERNEL);

		if (!chip)

			return -ENOMEM;



		/* platform chip_info isn't required */

		chip_info = spi->controller_data;

		if (chip_info) {

			/*

			 * DITFS and TDTYPE are only thing we don't set, but

			 * they probably shouldn't be changed by people.

			 */

			if (chip_info->ctl_reg || chip_info->enable_dma) {

				ret = -EINVAL;

				dev_err(&spi->dev, "don't set ctl_reg/enable_dma fields");

				goto error;

			}

			chip->cs_chg_udelay = chip_info->cs_chg_udelay;

			chip->idle_tx_val = chip_info->idle_tx_val;

			spi->bits_per_word = chip_info->bits_per_word;

		}

	}



	if (spi->bits_per_word != 8 && spi->bits_per_word != 16) {

		ret = -EINVAL;

		goto error;

	}



	/* translate common spi framework into our register

	 * following configure contents are same for tx and rx.

	 */



	if (spi->mode & SPI_CPHA)

		chip->ctl_reg &= ~TCKFE;

	else

		chip->ctl_reg |= TCKFE;



	if (spi->mode & SPI_LSB_FIRST)

		chip->ctl_reg |= TLSBIT;

	else

		chip->ctl_reg &= ~TLSBIT;



	/* Sport in master mode */

	chip->ctl_reg |= ITCLK | ITFS | TFSR | LATFS | LTFS;



	chip->baud = bfin_sport_hz_to_spi_baud(spi->max_speed_hz);



	chip->cs_gpio = spi->chip_select;

	ret = gpio_request(chip->cs_gpio, spi->modalias);

	if (ret)

		goto error;



	dev_dbg(&spi->dev, "setup spi chip %s, width is %d\n",

			spi->modalias, spi->bits_per_word);

	dev_dbg(&spi->dev, "ctl_reg is 0x%x, GPIO is %i\n",

			chip->ctl_reg, spi->chip_select);



	spi_set_ctldata(spi, chip);



	bfin_sport_spi_cs_deactive(chip);



	return ret;



 error:

	kfree(first);

	return ret;

}



/*

 * callback for spi framework.

 * clean driver specific data

 */

static void

bfin_sport_spi_cleanup(struct spi_device *spi)

{

	struct bfin_sport_spi_slave_data *chip = spi_get_ctldata(spi);



	if (!chip)

		return;



	gpio_free(chip->cs_gpio);



	kfree(chip);

}



static int

bfin_sport_spi_init_queue(struct bfin_sport_spi_master_data *drv_data)

{

	INIT_LIST_HEAD(&drv_data->queue);

	spin_lock_init(&drv_data->lock);



	drv_data->run = false;

	drv_data->busy = 0;



	/* init transfer tasklet */

	tasklet_init(&drv_data->pump_transfers,

		     bfin_sport_spi_pump_transfers, (unsigned long)drv_data);



	/* init messages workqueue */

	INIT_WORK(&drv_data->pump_messages, bfin_sport_spi_pump_messages);

	drv_data->workqueue =

	    create_singlethread_workqueue(dev_name(drv_data->master->dev.parent));

	if (drv_data->workqueue == NULL)

		return -EBUSY;



	return 0;

}



static int

bfin_sport_spi_start_queue(struct bfin_sport_spi_master_data *drv_data)

{

	unsigned long flags;



	spin_lock_irqsave(&drv_data->lock, flags);



	if (drv_data->run || drv_data->busy) {

		spin_unlock_irqrestore(&drv_data->lock, flags);

		return -EBUSY;

	}



	drv_data->run = true;

	drv_data->cur_msg = NULL;

	drv_data->cur_transfer = NULL;

	drv_data->cur_chip = NULL;

	spin_unlock_irqrestore(&drv_data->lock, flags);



	queue_work(drv_data->workqueue, &drv_data->pump_messages);



	return 0;

}



static inline int

bfin_sport_spi_stop_queue(struct bfin_sport_spi_master_data *drv_data)

{

	unsigned long flags;

	unsigned limit = 500;

	int status = 0;



	spin_lock_irqsave(&drv_data->lock, flags);



	/*

	 * This is a bit lame, but is optimized for the common execution path.

	 * A wait_queue on the drv_data->busy could be used, but then the common

	 * execution path (pump_messages) would be required to call wake_up or

	 * friends on every SPI message. Do this instead

	 */

	drv_data->run = false;

	while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) {

		spin_unlock_irqrestore(&drv_data->lock, flags);

		msleep(10);

		spin_lock_irqsave(&drv_data->lock, flags);

	}



	if (!list_empty(&drv_data->queue) || drv_data->busy)

		status = -EBUSY;



	spin_unlock_irqrestore(&drv_data->lock, flags);



	return status;

}



static inline int

bfin_sport_spi_destroy_queue(struct bfin_sport_spi_master_data *drv_data)

{

	int status;



	status = bfin_sport_spi_stop_queue(drv_data);

	if (status)

		return status;



	destroy_workqueue(drv_data->workqueue);



	return 0;

}



static int __devinit

bfin_sport_spi_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct bfin5xx_spi_master *platform_info;

	struct spi_master *master;

	struct resource *res, *ires;

	struct bfin_sport_spi_master_data *drv_data;

	int status;



	platform_info = dev->platform_data;



	/* Allocate master with space for drv_data */

	master = spi_alloc_master(dev, sizeof(*master) + 16);

	if (!master) {

		dev_err(dev, "cannot alloc spi_master\n");

		return -ENOMEM;

	}



	drv_data = spi_master_get_devdata(master);

	drv_data->master = master;

	drv_data->dev = dev;

	drv_data->pin_req = platform_info->pin_req;



	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;

	master->bus_num = pdev->id;

	master->num_chipselect = platform_info->num_chipselect;

	master->cleanup = bfin_sport_spi_cleanup;

	master->setup = bfin_sport_spi_setup;

	master->transfer = bfin_sport_spi_transfer;



	/* Find and map our resources */

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (res == NULL) {

		dev_err(dev, "cannot get IORESOURCE_MEM\n");

		status = -ENOENT;

		goto out_error_get_res;

	}



	drv_data->regs = ioremap(res->start, resource_size(res));

	if (drv_data->regs == NULL) {

		dev_err(dev, "cannot map registers\n");

		status = -ENXIO;

		goto out_error_ioremap;

	}



	ires = platform_get_resource(pdev, IORESOURCE_IRQ, 0);

	if (!ires) {

		dev_err(dev, "cannot get IORESOURCE_IRQ\n");

		status = -ENODEV;

		goto out_error_get_ires;

	}

	drv_data->err_irq = ires->start;



	/* Initial and start queue */

	status = bfin_sport_spi_init_queue(drv_data);

	if (status) {

		dev_err(dev, "problem initializing queue\n");

		goto out_error_queue_alloc;

	}



	status = bfin_sport_spi_start_queue(drv_data);

	if (status) {

		dev_err(dev, "problem starting queue\n");

		goto out_error_queue_alloc;

	}



	status = request_irq(drv_data->err_irq, sport_err_handler,

		0, "sport_spi_err", drv_data);

	if (status) {

		dev_err(dev, "unable to request sport err irq\n");

		goto out_error_irq;

	}



	status = peripheral_request_list(drv_data->pin_req, DRV_NAME);

	if (status) {

		dev_err(dev, "requesting peripherals failed\n");

		goto out_error_peripheral;

	}



	/* Register with the SPI framework */

	platform_set_drvdata(pdev, drv_data);

	status = spi_register_master(master);

	if (status) {

		dev_err(dev, "problem registering spi master\n");

		goto out_error_master;

	}



	dev_info(dev, "%s, regs_base@%p\n", DRV_DESC, drv_data->regs);

	return 0;



 out_error_master:

	peripheral_free_list(drv_data->pin_req);

 out_error_peripheral:

	free_irq(drv_data->err_irq, drv_data);

 out_error_irq:

 out_error_queue_alloc:

	bfin_sport_spi_destroy_queue(drv_data);

 out_error_get_ires:

	iounmap(drv_data->regs);

 out_error_ioremap:

 out_error_get_res:

	spi_master_put(master);



	return status;

}



/* stop hardware and remove the driver */

static int __devexit

bfin_sport_spi_remove(struct platform_device *pdev)

{

	struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev);

	int status = 0;



	if (!drv_data)

		return 0;



	/* Remove the queue */

	status = bfin_sport_spi_destroy_queue(drv_data);

	if (status)

		return status;



	/* Disable the SSP at the peripheral and SOC level */

	bfin_sport_spi_disable(drv_data);



	/* Disconnect from the SPI framework */

	spi_unregister_master(drv_data->master);



	peripheral_free_list(drv_data->pin_req);



	/* Prevent double remove */

	platform_set_drvdata(pdev, NULL);



	return 0;

}



#ifdef CONFIG_PM

static int

bfin_sport_spi_suspend(struct platform_device *pdev, pm_message_t state)

{

	struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev);

	int status;



	status = bfin_sport_spi_stop_queue(drv_data);

	if (status)

		return status;



	/* stop hardware */

	bfin_sport_spi_disable(drv_data);



	return status;

}



static int

bfin_sport_spi_resume(struct platform_device *pdev)

{

	struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev);

	int status;



	/* Enable the SPI interface */

	bfin_sport_spi_enable(drv_data);



	/* Start the queue running */

	status = bfin_sport_spi_start_queue(drv_data);

	if (status)

		dev_err(drv_data->dev, "problem resuming queue\n");



	return status;

}

#else

# define bfin_sport_spi_suspend NULL

# define bfin_sport_spi_resume  NULL

#endif



static struct platform_driver bfin_sport_spi_driver = {

	.driver	= {

		.name = DRV_NAME,

		.owner = THIS_MODULE,

	},

	.probe   = bfin_sport_spi_probe,

	.remove  = __devexit_p(bfin_sport_spi_remove),

	.suspend = bfin_sport_spi_suspend,

	.resume  = bfin_sport_spi_resume,

};



static int __init bfin_sport_spi_init(void)

{

	return platform_driver_register(&bfin_sport_spi_driver);

}

module_init(bfin_sport_spi_init);



static void __exit bfin_sport_spi_exit(void)

{

	platform_driver_unregister(&bfin_sport_spi_driver);

}

module_exit(bfin_sport_spi_exit);