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- /*
- * 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);
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