diff options
Diffstat (limited to 'drivers/spi/spi-bfin5xx.c')
| -rw-r--r-- | drivers/spi/spi-bfin5xx.c | 1530 |
1 files changed, 1530 insertions, 0 deletions
diff --git a/drivers/spi/spi-bfin5xx.c b/drivers/spi/spi-bfin5xx.c new file mode 100644 index 0000000..f706dba --- /dev/null +++ b/drivers/spi/spi-bfin5xx.c @@ -0,0 +1,1530 @@ +/* + * Blackfin On-Chip SPI Driver + * + * Copyright 2004-2010 Analog Devices Inc. + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * 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/slab.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/dma-mapping.h> +#include <linux/spi/spi.h> +#include <linux/workqueue.h> + +#include <asm/dma.h> +#include <asm/portmux.h> +#include <asm/bfin5xx_spi.h> +#include <asm/cacheflush.h> + +#define DRV_NAME "bfin-spi" +#define DRV_AUTHOR "Bryan Wu, Luke Yang" +#define DRV_DESC "Blackfin on-chip SPI Controller Driver" +#define DRV_VERSION "1.0" + +MODULE_AUTHOR(DRV_AUTHOR); +MODULE_DESCRIPTION(DRV_DESC); +MODULE_LICENSE("GPL"); + +#define START_STATE ((void *)0) +#define RUNNING_STATE ((void *)1) +#define DONE_STATE ((void *)2) +#define ERROR_STATE ((void *)-1) + +struct bfin_spi_master_data; + +struct bfin_spi_transfer_ops { + void (*write) (struct bfin_spi_master_data *); + void (*read) (struct bfin_spi_master_data *); + void (*duplex) (struct bfin_spi_master_data *); +}; + +struct bfin_spi_master_data { + /* Driver model hookup */ + struct platform_device *pdev; + + /* SPI framework hookup */ + struct spi_master *master; + + /* Regs base of SPI controller */ + void __iomem *regs_base; + + /* Pin request list */ + u16 *pin_req; + + /* BFIN hookup */ + struct bfin5xx_spi_master *master_info; + + /* Driver message queue */ + struct workqueue_struct *workqueue; + struct work_struct pump_messages; + spinlock_t lock; + struct list_head queue; + int busy; + bool running; + + /* Message Transfer pump */ + struct tasklet_struct pump_transfers; + + /* Current message transfer state info */ + struct spi_message *cur_msg; + struct spi_transfer *cur_transfer; + struct bfin_spi_slave_data *cur_chip; + size_t len_in_bytes; + size_t len; + void *tx; + void *tx_end; + void *rx; + void *rx_end; + + /* DMA stuffs */ + int dma_channel; + int dma_mapped; + int dma_requested; + dma_addr_t rx_dma; + dma_addr_t tx_dma; + + int irq_requested; + int spi_irq; + + size_t rx_map_len; + size_t tx_map_len; + u8 n_bytes; + u16 ctrl_reg; + u16 flag_reg; + + int cs_change; + const struct bfin_spi_transfer_ops *ops; +}; + +struct bfin_spi_slave_data { + u16 ctl_reg; + u16 baud; + u16 flag; + + u8 chip_select_num; + u8 enable_dma; + u16 cs_chg_udelay; /* Some devices require > 255usec delay */ + u32 cs_gpio; + u16 idle_tx_val; + u8 pio_interrupt; /* use spi data irq */ + const struct bfin_spi_transfer_ops *ops; +}; + +#define DEFINE_SPI_REG(reg, off) \ +static inline u16 read_##reg(struct bfin_spi_master_data *drv_data) \ + { return bfin_read16(drv_data->regs_base + off); } \ +static inline void write_##reg(struct bfin_spi_master_data *drv_data, u16 v) \ + { bfin_write16(drv_data->regs_base + off, v); } + +DEFINE_SPI_REG(CTRL, 0x00) +DEFINE_SPI_REG(FLAG, 0x04) +DEFINE_SPI_REG(STAT, 0x08) +DEFINE_SPI_REG(TDBR, 0x0C) +DEFINE_SPI_REG(RDBR, 0x10) +DEFINE_SPI_REG(BAUD, 0x14) +DEFINE_SPI_REG(SHAW, 0x18) + +static void bfin_spi_enable(struct bfin_spi_master_data *drv_data) +{ + u16 cr; + + cr = read_CTRL(drv_data); + write_CTRL(drv_data, (cr | BIT_CTL_ENABLE)); +} + +static void bfin_spi_disable(struct bfin_spi_master_data *drv_data) +{ + u16 cr; + + cr = read_CTRL(drv_data); + write_CTRL(drv_data, (cr & (~BIT_CTL_ENABLE))); +} + +/* Caculate the SPI_BAUD register value based on input HZ */ +static u16 hz_to_spi_baud(u32 speed_hz) +{ + u_long sclk = get_sclk(); + u16 spi_baud = (sclk / (2 * speed_hz)); + + if ((sclk % (2 * speed_hz)) > 0) + spi_baud++; + + if (spi_baud < MIN_SPI_BAUD_VAL) + spi_baud = MIN_SPI_BAUD_VAL; + + return spi_baud; +} + +static int bfin_spi_flush(struct bfin_spi_master_data *drv_data) +{ + unsigned long limit = loops_per_jiffy << 1; + + /* wait for stop and clear stat */ + while (!(read_STAT(drv_data) & BIT_STAT_SPIF) && --limit) + cpu_relax(); + + write_STAT(drv_data, BIT_STAT_CLR); + + return limit; +} + +/* Chip select operation functions for cs_change flag */ +static void bfin_spi_cs_active(struct bfin_spi_master_data *drv_data, struct bfin_spi_slave_data *chip) +{ + if (likely(chip->chip_select_num < MAX_CTRL_CS)) { + u16 flag = read_FLAG(drv_data); + + flag &= ~chip->flag; + + write_FLAG(drv_data, flag); + } else { + gpio_set_value(chip->cs_gpio, 0); + } +} + +static void bfin_spi_cs_deactive(struct bfin_spi_master_data *drv_data, + struct bfin_spi_slave_data *chip) +{ + if (likely(chip->chip_select_num < MAX_CTRL_CS)) { + u16 flag = read_FLAG(drv_data); + + flag |= chip->flag; + + write_FLAG(drv_data, flag); + } else { + gpio_set_value(chip->cs_gpio, 1); + } + + /* Move delay here for consistency */ + if (chip->cs_chg_udelay) + udelay(chip->cs_chg_udelay); +} + +/* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */ +static inline void bfin_spi_cs_enable(struct bfin_spi_master_data *drv_data, + struct bfin_spi_slave_data *chip) +{ + if (chip->chip_select_num < MAX_CTRL_CS) { + u16 flag = read_FLAG(drv_data); + + flag |= (chip->flag >> 8); + + write_FLAG(drv_data, flag); + } +} + +static inline void bfin_spi_cs_disable(struct bfin_spi_master_data *drv_data, + struct bfin_spi_slave_data *chip) +{ + if (chip->chip_select_num < MAX_CTRL_CS) { + u16 flag = read_FLAG(drv_data); + + flag &= ~(chip->flag >> 8); + + write_FLAG(drv_data, flag); + } +} + +/* stop controller and re-config current chip*/ +static void bfin_spi_restore_state(struct bfin_spi_master_data *drv_data) +{ + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + + /* Clear status and disable clock */ + write_STAT(drv_data, BIT_STAT_CLR); + bfin_spi_disable(drv_data); + dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n"); + + SSYNC(); + + /* Load the registers */ + write_CTRL(drv_data, chip->ctl_reg); + write_BAUD(drv_data, chip->baud); + + bfin_spi_enable(drv_data); + bfin_spi_cs_active(drv_data, chip); +} + +/* used to kick off transfer in rx mode and read unwanted RX data */ +static inline void bfin_spi_dummy_read(struct bfin_spi_master_data *drv_data) +{ + (void) read_RDBR(drv_data); +} + +static void bfin_spi_u8_writer(struct bfin_spi_master_data *drv_data) +{ + /* clear RXS (we check for RXS inside the loop) */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->tx < drv_data->tx_end) { + write_TDBR(drv_data, (*(u8 *) (drv_data->tx++))); + /* wait until transfer finished. + checking SPIF or TXS may not guarantee transfer completion */ + while (!(read_STAT(drv_data) & BIT_STAT_RXS)) + cpu_relax(); + /* discard RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + } +} + +static void bfin_spi_u8_reader(struct bfin_spi_master_data *drv_data) +{ + u16 tx_val = drv_data->cur_chip->idle_tx_val; + + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + write_TDBR(drv_data, tx_val); + while (!(read_STAT(drv_data) & BIT_STAT_RXS)) + cpu_relax(); + *(u8 *) (drv_data->rx++) = read_RDBR(drv_data); + } +} + +static void bfin_spi_u8_duplex(struct bfin_spi_master_data *drv_data) +{ + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + write_TDBR(drv_data, (*(u8 *) (drv_data->tx++))); + while (!(read_STAT(drv_data) & BIT_STAT_RXS)) + cpu_relax(); + *(u8 *) (drv_data->rx++) = read_RDBR(drv_data); + } +} + +static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8 = { + .write = bfin_spi_u8_writer, + .read = bfin_spi_u8_reader, + .duplex = bfin_spi_u8_duplex, +}; + +static void bfin_spi_u16_writer(struct bfin_spi_master_data *drv_data) +{ + /* clear RXS (we check for RXS inside the loop) */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->tx < drv_data->tx_end) { + write_TDBR(drv_data, (*(u16 *) (drv_data->tx))); + drv_data->tx += 2; + /* wait until transfer finished. + checking SPIF or TXS may not guarantee transfer completion */ + while (!(read_STAT(drv_data) & BIT_STAT_RXS)) + cpu_relax(); + /* discard RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + } +} + +static void bfin_spi_u16_reader(struct bfin_spi_master_data *drv_data) +{ + u16 tx_val = drv_data->cur_chip->idle_tx_val; + + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + write_TDBR(drv_data, tx_val); + while (!(read_STAT(drv_data) & BIT_STAT_RXS)) + cpu_relax(); + *(u16 *) (drv_data->rx) = read_RDBR(drv_data); + drv_data->rx += 2; + } +} + +static void bfin_spi_u16_duplex(struct bfin_spi_master_data *drv_data) +{ + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + write_TDBR(drv_data, (*(u16 *) (drv_data->tx))); + drv_data->tx += 2; + while (!(read_STAT(drv_data) & BIT_STAT_RXS)) + cpu_relax(); + *(u16 *) (drv_data->rx) = read_RDBR(drv_data); + drv_data->rx += 2; + } +} + +static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16 = { + .write = bfin_spi_u16_writer, + .read = bfin_spi_u16_reader, + .duplex = bfin_spi_u16_duplex, +}; + +/* test if there is more transfer to be done */ +static void *bfin_spi_next_transfer(struct bfin_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; + } else + return DONE_STATE; +} + +/* + * caller already set message->status; + * dma and pio irqs are blocked give finished message back + */ +static void bfin_spi_giveback(struct bfin_spi_master_data *drv_data) +{ + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + struct spi_transfer *last_transfer; + unsigned long flags; + struct spi_message *msg; + + spin_lock_irqsave(&drv_data->lock, flags); + msg = drv_data->cur_msg; + 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); + + last_transfer = list_entry(msg->transfers.prev, + struct spi_transfer, transfer_list); + + msg->state = NULL; + + if (!drv_data->cs_change) + bfin_spi_cs_deactive(drv_data, chip); + + /* Not stop spi in autobuffer mode */ + if (drv_data->tx_dma != 0xFFFF) + bfin_spi_disable(drv_data); + + if (msg->complete) + msg->complete(msg->context); +} + +/* spi data irq handler */ +static irqreturn_t bfin_spi_pio_irq_handler(int irq, void *dev_id) +{ + struct bfin_spi_master_data *drv_data = dev_id; + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + struct spi_message *msg = drv_data->cur_msg; + int n_bytes = drv_data->n_bytes; + int loop = 0; + + /* wait until transfer finished. */ + while (!(read_STAT(drv_data) & BIT_STAT_RXS)) + cpu_relax(); + + if ((drv_data->tx && drv_data->tx >= drv_data->tx_end) || + (drv_data->rx && drv_data->rx >= (drv_data->rx_end - n_bytes))) { + /* last read */ + if (drv_data->rx) { + dev_dbg(&drv_data->pdev->dev, "last read\n"); + if (n_bytes % 2) { + u16 *buf = (u16 *)drv_data->rx; + for (loop = 0; loop < n_bytes / 2; loop++) + *buf++ = read_RDBR(drv_data); + } else { + u8 *buf = (u8 *)drv_data->rx; + for (loop = 0; loop < n_bytes; loop++) + *buf++ = read_RDBR(drv_data); + } + drv_data->rx += n_bytes; + } + + msg->actual_length += drv_data->len_in_bytes; + if (drv_data->cs_change) + bfin_spi_cs_deactive(drv_data, chip); + /* Move to next transfer */ + msg->state = bfin_spi_next_transfer(drv_data); + + disable_irq_nosync(drv_data->spi_irq); + + /* Schedule transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + return IRQ_HANDLED; + } + + if (drv_data->rx && drv_data->tx) { + /* duplex */ + dev_dbg(&drv_data->pdev->dev, "duplex: write_TDBR\n"); + if (n_bytes % 2) { + u16 *buf = (u16 *)drv_data->rx; + u16 *buf2 = (u16 *)drv_data->tx; + for (loop = 0; loop < n_bytes / 2; loop++) { + *buf++ = read_RDBR(drv_data); + write_TDBR(drv_data, *buf2++); + } + } else { + u8 *buf = (u8 *)drv_data->rx; + u8 *buf2 = (u8 *)drv_data->tx; + for (loop = 0; loop < n_bytes; loop++) { + *buf++ = read_RDBR(drv_data); + write_TDBR(drv_data, *buf2++); + } + } + } else if (drv_data->rx) { + /* read */ + dev_dbg(&drv_data->pdev->dev, "read: write_TDBR\n"); + if (n_bytes % 2) { + u16 *buf = (u16 *)drv_data->rx; + for (loop = 0; loop < n_bytes / 2; loop++) { + *buf++ = read_RDBR(drv_data); + write_TDBR(drv_data, chip->idle_tx_val); + } + } else { + u8 *buf = (u8 *)drv_data->rx; + for (loop = 0; loop < n_bytes; loop++) { + *buf++ = read_RDBR(drv_data); + write_TDBR(drv_data, chip->idle_tx_val); + } + } + } else if (drv_data->tx) { + /* write */ + dev_dbg(&drv_data->pdev->dev, "write: write_TDBR\n"); + if (n_bytes % 2) { + u16 *buf = (u16 *)drv_data->tx; + for (loop = 0; loop < n_bytes / 2; loop++) { + read_RDBR(drv_data); + write_TDBR(drv_data, *buf++); + } + } else { + u8 *buf = (u8 *)drv_data->tx; + for (loop = 0; loop < n_bytes; loop++) { + read_RDBR(drv_data); + write_TDBR(drv_data, *buf++); + } + } + } + + if (drv_data->tx) + drv_data->tx += n_bytes; + if (drv_data->rx) + drv_data->rx += n_bytes; + + return IRQ_HANDLED; +} + +static irqreturn_t bfin_spi_dma_irq_handler(int irq, void *dev_id) +{ + struct bfin_spi_master_data *drv_data = dev_id; + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + struct spi_message *msg = drv_data->cur_msg; + unsigned long timeout; + unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel); + u16 spistat = read_STAT(drv_data); + + dev_dbg(&drv_data->pdev->dev, + "in dma_irq_handler dmastat:0x%x spistat:0x%x\n", + dmastat, spistat); + + if (drv_data->rx != NULL) { + u16 cr = read_CTRL(drv_data); + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + write_CTRL(drv_data, cr & ~BIT_CTL_ENABLE); /* Disable SPI */ + write_CTRL(drv_data, cr & ~BIT_CTL_TIMOD); /* Restore State */ + write_STAT(drv_data, BIT_STAT_CLR); /* Clear Status */ + } + + clear_dma_irqstat(drv_data->dma_channel); + + /* + * wait for the last transaction shifted out. HRM states: + * at this point there may still be data in the SPI DMA FIFO waiting + * to be transmitted ... software needs to poll TXS in the SPI_STAT + * register until it goes low for 2 successive reads + */ + if (drv_data->tx != NULL) { + while ((read_STAT(drv_data) & BIT_STAT_TXS) || + (read_STAT(drv_data) & BIT_STAT_TXS)) + cpu_relax(); + } + + dev_dbg(&drv_data->pdev->dev, + "in dma_irq_handler dmastat:0x%x spistat:0x%x\n", + dmastat, read_STAT(drv_data)); + + timeout = jiffies + HZ; + while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) + if (!time_before(jiffies, timeout)) { + dev_warn(&drv_data->pdev->dev, "timeout waiting for SPIF"); + break; + } else + cpu_relax(); + + if ((dmastat & DMA_ERR) && (spistat & BIT_STAT_RBSY)) { + msg->state = ERROR_STATE; + dev_err(&drv_data->pdev->dev, "dma receive: fifo/buffer overflow\n"); + } else { + msg->actual_length += drv_data->len_in_bytes; + + if (drv_data->cs_change) + bfin_spi_cs_deactive(drv_data, chip); + + /* Move to next transfer */ + msg->state = bfin_spi_next_transfer(drv_data); + } + + /* Schedule transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + + /* free the irq handler before next transfer */ + dev_dbg(&drv_data->pdev->dev, + "disable dma channel irq%d\n", + drv_data->dma_channel); + dma_disable_irq_nosync(drv_data->dma_channel); + + return IRQ_HANDLED; +} + +static void bfin_spi_pump_transfers(unsigned long data) +{ + struct bfin_spi_master_data *drv_data = (struct bfin_spi_master_data *)data; + struct spi_message *message = NULL; + struct spi_transfer *transfer = NULL; + struct spi_transfer *previous = NULL; + struct bfin_spi_slave_data *chip = NULL; + unsigned int bits_per_word; + u16 cr, cr_width, dma_width, dma_config; + u32 tranf_success = 1; + u8 full_duplex = 0; + + /* Get current state information */ + message = drv_data->cur_msg; + transfer = drv_data->cur_transfer; + chip = drv_data->cur_chip; + + /* + * if msg is error or done, report it back using complete() callback + */ + + /* Handle for abort */ + if (message->state == ERROR_STATE) { + dev_dbg(&drv_data->pdev->dev, "transfer: we've hit an error\n"); + message->status = -EIO; + bfin_spi_giveback(drv_data); + return; + } + + /* Handle end of message */ + if (message->state == DONE_STATE) { + dev_dbg(&drv_data->pdev->dev, "transfer: all done!\n"); + message->status = 0; + bfin_spi_giveback(drv_data); + return; + } + + /* Delay if requested at end of transfer */ + if (message->state == RUNNING_STATE) { + dev_dbg(&drv_data->pdev->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); + } + + /* Flush any existing transfers that may be sitting in the hardware */ + if (bfin_spi_flush(drv_data) == 0) { + dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n"); + message->status = -EIO; + bfin_spi_giveback(drv_data); + return; + } + + if (transfer->len == 0) { + /* Move to next transfer of this msg */ + message->state = bfin_spi_next_transfer(drv_data); + /* Schedule next transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + return; + } + + 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->pdev->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->pdev->dev, "rx_buf is %p, rx_end is %p\n", + transfer->rx_buf, drv_data->rx_end); + } else { + drv_data->rx = NULL; + } + + drv_data->rx_dma = transfer->rx_dma; + drv_data->tx_dma = transfer->tx_dma; + drv_data->len_in_bytes = transfer->len; + 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 > 0) && (bits_per_word % 16 == 0)) { + drv_data->n_bytes = bits_per_word/8; + drv_data->len = (transfer->len) >> 1; + cr_width = BIT_CTL_WORDSIZE; + drv_data->ops = &bfin_bfin_spi_transfer_ops_u16; + } else if ((bits_per_word > 0) && (bits_per_word % 8 == 0)) { + drv_data->n_bytes = bits_per_word/8; + drv_data->len = transfer->len; + cr_width = 0; + drv_data->ops = &bfin_bfin_spi_transfer_ops_u8; + } else { + dev_err(&drv_data->pdev->dev, "transfer: unsupported bits_per_word\n"); + message->status = -EINVAL; + bfin_spi_giveback(drv_data); + return; + } + cr = read_CTRL(drv_data) & ~(BIT_CTL_TIMOD | BIT_CTL_WORDSIZE); + cr |= cr_width; + write_CTRL(drv_data, cr); + + dev_dbg(&drv_data->pdev->dev, + "transfer: drv_data->ops is %p, chip->ops is %p, u8_ops is %p\n", + drv_data->ops, chip->ops, &bfin_bfin_spi_transfer_ops_u8); + + message->state = RUNNING_STATE; + dma_config = 0; + + /* Speed setup (surely valid because already checked) */ + if (transfer->speed_hz) + write_BAUD(drv_data, hz_to_spi_baud(transfer->speed_hz)); + else + write_BAUD(drv_data, chip->baud); + + write_STAT(drv_data, BIT_STAT_CLR); + bfin_spi_cs_active(drv_data, chip); + + dev_dbg(&drv_data->pdev->dev, + "now pumping a transfer: width is %d, len is %d\n", + cr_width, transfer->len); + + /* + * Try to map dma buffer and do a dma transfer. If successful use, + * different way to r/w according to the enable_dma settings and if + * we are not doing a full duplex transfer (since the hardware does + * not support full duplex DMA transfers). + */ + if (!full_duplex && drv_data->cur_chip->enable_dma + && drv_data->len > 6) { + + unsigned long dma_start_addr, flags; + + disable_dma(drv_data->dma_channel); + clear_dma_irqstat(drv_data->dma_channel); + + /* config dma channel */ + dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n"); + set_dma_x_count(drv_data->dma_channel, drv_data->len); + if (cr_width == BIT_CTL_WORDSIZE) { + set_dma_x_modify(drv_data->dma_channel, 2); + dma_width = WDSIZE_16; + } else { + set_dma_x_modify(drv_data->dma_channel, 1); + dma_width = WDSIZE_8; + } + + /* poll for SPI completion before start */ + while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) + cpu_relax(); + + /* dirty hack for autobuffer DMA mode */ + if (drv_data->tx_dma == 0xFFFF) { + dev_dbg(&drv_data->pdev->dev, + "doing autobuffer DMA out.\n"); + + /* no irq in autobuffer mode */ + dma_config = + (DMAFLOW_AUTO | RESTART | dma_width | DI_EN); + set_dma_config(drv_data->dma_channel, dma_config); + set_dma_start_addr(drv_data->dma_channel, + (unsigned long)drv_data->tx); + enable_dma(drv_data->dma_channel); + + /* start SPI transfer */ + write_CTRL(drv_data, cr | BIT_CTL_TIMOD_DMA_TX); + + /* just return here, there can only be one transfer + * in this mode + */ + message->status = 0; + bfin_spi_giveback(drv_data); + return; + } + + /* In dma mode, rx or tx must be NULL in one transfer */ + dma_config = (RESTART | dma_width | DI_EN); + if (drv_data->rx != NULL) { + /* set transfer mode, and enable SPI */ + dev_dbg(&drv_data->pdev->dev, "doing DMA in to %p (size %zx)\n", + drv_data->rx, drv_data->len_in_bytes); + + /* invalidate caches, if needed */ + if (bfin_addr_dcacheable((unsigned long) drv_data->rx)) + invalidate_dcache_range((unsigned long) drv_data->rx, + (unsigned long) (drv_data->rx + + drv_data->len_in_bytes)); + + dma_config |= WNR; + dma_start_addr = (unsigned long)drv_data->rx; + cr |= BIT_CTL_TIMOD_DMA_RX | BIT_CTL_SENDOPT; + + } else if (drv_data->tx != NULL) { + dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n"); + + /* flush caches, if needed */ + if (bfin_addr_dcacheable((unsigned long) drv_data->tx)) + flush_dcache_range((unsigned long) drv_data->tx, + (unsigned long) (drv_data->tx + + drv_data->len_in_bytes)); + + dma_start_addr = (unsigned long)drv_data->tx; + cr |= BIT_CTL_TIMOD_DMA_TX; + + } else + BUG(); + + /* oh man, here there be monsters ... and i dont mean the + * fluffy cute ones from pixar, i mean the kind that'll eat + * your data, kick your dog, and love it all. do *not* try + * and change these lines unless you (1) heavily test DMA + * with SPI flashes on a loaded system (e.g. ping floods), + * (2) know just how broken the DMA engine interaction with + * the SPI peripheral is, and (3) have someone else to blame + * when you screw it all up anyways. + */ + set_dma_start_addr(drv_data->dma_channel, dma_start_addr); + set_dma_config(drv_data->dma_channel, dma_config); + local_irq_save(flags); + SSYNC(); + write_CTRL(drv_data, cr); + enable_dma(drv_data->dma_channel); + dma_enable_irq(drv_data->dma_channel); + local_irq_restore(flags); + + return; + } + + /* + * We always use SPI_WRITE mode (transfer starts with TDBR write). + * SPI_READ mode (transfer starts with RDBR read) seems to have + * problems with setting up the output value in TDBR prior to the + * start of the transfer. + */ + write_CTRL(drv_data, cr | BIT_CTL_TXMOD); + + if (chip->pio_interrupt) { + /* SPI irq should have been disabled by now */ + + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + /* start transfer */ + if (drv_data->tx == NULL) + write_TDBR(drv_data, chip->idle_tx_val); + else { + int loop; + if (bits_per_word % 16 == 0) { + u16 *buf = (u16 *)drv_data->tx; + for (loop = 0; loop < bits_per_word / 16; + loop++) { + write_TDBR(drv_data, *buf++); + } + } else if (bits_per_word % 8 == 0) { + u8 *buf = (u8 *)drv_data->tx; + for (loop = 0; loop < bits_per_word / 8; loop++) + write_TDBR(drv_data, *buf++); + } + + drv_data->tx += drv_data->n_bytes; + } + + /* once TDBR is empty, interrupt is triggered */ + enable_irq(drv_data->spi_irq); + return; + } + + /* IO mode */ + dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n"); + + if (full_duplex) { + /* full duplex mode */ + BUG_ON((drv_data->tx_end - drv_data->tx) != + (drv_data->rx_end - drv_data->rx)); + dev_dbg(&drv_data->pdev->dev, + "IO duplex: cr is 0x%x\n", cr); + + 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 */ + dev_dbg(&drv_data->pdev->dev, + "IO write: cr is 0x%x\n", cr); + + 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 */ + dev_dbg(&drv_data->pdev->dev, + "IO read: cr is 0x%x\n", cr); + + drv_data->ops->read(drv_data); + if (drv_data->rx != drv_data->rx_end) + tranf_success = 0; + } + + if (!tranf_success) { + dev_dbg(&drv_data->pdev->dev, + "IO write error!\n"); + message->state = ERROR_STATE; + } else { + /* Update total byte transferred */ + message->actual_length += drv_data->len_in_bytes; + /* Move to next transfer of this msg */ + message->state = bfin_spi_next_transfer(drv_data); + if (drv_data->cs_change) + bfin_spi_cs_deactive(drv_data, chip); + } + + /* Schedule next transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); +} + +/* pop a msg from queue and kick off real transfer */ +static void bfin_spi_pump_messages(struct work_struct *work) +{ + struct bfin_spi_master_data *drv_data; + unsigned long flags; + + drv_data = container_of(work, struct bfin_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->running) { + /* 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 */ + drv_data->cur_msg = list_entry(drv_data->queue.next, + struct spi_message, queue); + + /* Setup the SSP using the per chip configuration */ + drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi); + bfin_spi_restore_state(drv_data); + + list_del_init(&drv_data->cur_msg->queue); + + /* Initial 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); + + dev_dbg(&drv_data->pdev->dev, "got a message to pump, " + "state is set to: baud %d, flag 0x%x, ctl 0x%x\n", + drv_data->cur_chip->baud, drv_data->cur_chip->flag, + drv_data->cur_chip->ctl_reg); + + dev_dbg(&drv_data->pdev->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_spi_transfer(struct spi_device *spi, struct spi_message *msg) +{ + struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master); + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + if (!drv_data->running) { + 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->running && !drv_data->busy) + queue_work(drv_data->workqueue, &drv_data->pump_messages); + + spin_unlock_irqrestore(&drv_data->lock, flags); + + return 0; +} + +#define MAX_SPI_SSEL 7 + +static u16 ssel[][MAX_SPI_SSEL] = { + {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3, + P_SPI0_SSEL4, P_SPI0_SSEL5, + P_SPI0_SSEL6, P_SPI0_SSEL7}, + + {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3, + P_SPI1_SSEL4, P_SPI1_SSEL5, + P_SPI1_SSEL6, P_SPI1_SSEL7}, + + {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3, + P_SPI2_SSEL4, P_SPI2_SSEL5, + P_SPI2_SSEL6, P_SPI2_SSEL7}, +}; + +/* setup for devices (may be called multiple times -- not just first setup) */ +static int bfin_spi_setup(struct spi_device *spi) +{ + struct bfin5xx_spi_chip *chip_info; + struct bfin_spi_slave_data *chip = NULL; + struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master); + u16 bfin_ctl_reg; + int ret = -EINVAL; + + /* Only alloc (or use chip_info) on first setup */ + chip_info = NULL; + chip = spi_get_ctldata(spi); + if (chip == NULL) { + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (!chip) { + dev_err(&spi->dev, "cannot allocate chip data\n"); + ret = -ENOMEM; + goto error; + } + + chip->enable_dma = 0; + chip_info = spi->controller_data; + } + + /* Let people set non-standard bits directly */ + bfin_ctl_reg = BIT_CTL_OPENDRAIN | BIT_CTL_EMISO | + BIT_CTL_PSSE | BIT_CTL_GM | BIT_CTL_SZ; + + /* chip_info isn't always needed */ + if (chip_info) { + /* Make sure people stop trying to set fields via ctl_reg + * when they should actually be using common SPI framework. + * Currently we let through: WOM EMISO PSSE GM SZ. + * Not sure if a user actually needs/uses any of these, + * but let's assume (for now) they do. + */ + if (chip_info->ctl_reg & ~bfin_ctl_reg) { + dev_err(&spi->dev, "do not set bits in ctl_reg " + "that the SPI framework manages\n"); + goto error; + } + chip->enable_dma = chip_info->enable_dma != 0 + && drv_data->master_info->enable_dma; + chip->ctl_reg = chip_info->ctl_reg; + chip->cs_chg_udelay = chip_info->cs_chg_udelay; + chip->idle_tx_val = chip_info->idle_tx_val; + chip->pio_interrupt = chip_info->pio_interrupt; + spi->bits_per_word = chip_info->bits_per_word; + } else { + /* force a default base state */ + chip->ctl_reg &= bfin_ctl_reg; + } + + if (spi->bits_per_word % 8) { + dev_err(&spi->dev, "%d bits_per_word is not supported\n", + spi->bits_per_word); + goto error; + } + + /* translate common spi framework into our register */ + if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) { + dev_err(&spi->dev, "unsupported spi modes detected\n"); + goto error; + } + if (spi->mode & SPI_CPOL) + chip->ctl_reg |= BIT_CTL_CPOL; + if (spi->mode & SPI_CPHA) + chip->ctl_reg |= BIT_CTL_CPHA; + if (spi->mode & SPI_LSB_FIRST) + chip->ctl_reg |= BIT_CTL_LSBF; + /* we dont support running in slave mode (yet?) */ + chip->ctl_reg |= BIT_CTL_MASTER; + + /* + * Notice: for blackfin, the speed_hz is the value of register + * SPI_BAUD, not the real baudrate + */ + chip->baud = hz_to_spi_baud(spi->max_speed_hz); + chip->chip_select_num = spi->chip_select; + if (chip->chip_select_num < MAX_CTRL_CS) { + if (!(spi->mode & SPI_CPHA)) + dev_warn(&spi->dev, "Warning: SPI CPHA not set:" + " Slave Select not under software control!\n" + " See Documentation/blackfin/bfin-spi-notes.txt"); + + chip->flag = (1 << spi->chip_select) << 8; + } else + chip->cs_gpio = chip->chip_select_num - MAX_CTRL_CS; + + if (chip->enable_dma && chip->pio_interrupt) { + dev_err(&spi->dev, "enable_dma is set, " + "do not set pio_interrupt\n"); + goto error; + } + /* + * if any one SPI chip is registered and wants DMA, request the + * DMA channel for it + */ + if (chip->enable_dma && !drv_data->dma_requested) { + /* register dma irq handler */ + ret = request_dma(drv_data->dma_channel, "BFIN_SPI_DMA"); + if (ret) { + dev_err(&spi->dev, + "Unable to request BlackFin SPI DMA channel\n"); + goto error; + } + drv_data->dma_requested = 1; + + ret = set_dma_callback(drv_data->dma_channel, + bfin_spi_dma_irq_handler, drv_data); + if (ret) { + dev_err(&spi->dev, "Unable to set dma callback\n"); + goto error; + } + dma_disable_irq(drv_data->dma_channel); + } + + if (chip->pio_interrupt && !drv_data->irq_requested) { + ret = request_irq(drv_data->spi_irq, bfin_spi_pio_irq_handler, + IRQF_DISABLED, "BFIN_SPI", drv_data); + if (ret) { + dev_err(&spi->dev, "Unable to register spi IRQ\n"); + goto error; + } + drv_data->irq_requested = 1; + /* we use write mode, spi irq has to be disabled here */ + disable_irq(drv_data->spi_irq); + } + + if (chip->chip_select_num >= MAX_CTRL_CS) { + /* Only request on first setup */ + if (spi_get_ctldata(spi) == NULL) { + ret = gpio_request(chip->cs_gpio, spi->modalias); + if (ret) { + dev_err(&spi->dev, "gpio_request() error\n"); + goto pin_error; + } + gpio_direction_output(chip->cs_gpio, 1); + } + } + + dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d\n", + spi->modalias, spi->bits_per_word, chip->enable_dma); + dev_dbg(&spi->dev, "ctl_reg is 0x%x, flag_reg is 0x%x\n", + chip->ctl_reg, chip->flag); + + spi_set_ctldata(spi, chip); + + dev_dbg(&spi->dev, "chip select number is %d\n", chip->chip_select_num); + if (chip->chip_select_num < MAX_CTRL_CS) { + ret = peripheral_request(ssel[spi->master->bus_num] + [chip->chip_select_num-1], spi->modalias); + if (ret) { + dev_err(&spi->dev, "peripheral_request() error\n"); + goto pin_error; + } + } + + bfin_spi_cs_enable(drv_data, chip); + bfin_spi_cs_deactive(drv_data, chip); + + return 0; + + pin_error: + if (chip->chip_select_num >= MAX_CTRL_CS) + gpio_free(chip->cs_gpio); + else + peripheral_free(ssel[spi->master->bus_num] + [chip->chip_select_num - 1]); + error: + if (chip) { + if (drv_data->dma_requested) + free_dma(drv_data->dma_channel); + drv_data->dma_requested = 0; + + kfree(chip); + /* prevent free 'chip' twice */ + spi_set_ctldata(spi, NULL); + } + + return ret; +} + +/* + * callback for spi framework. + * clean driver specific data + */ +static void bfin_spi_cleanup(struct spi_device *spi) +{ + struct bfin_spi_slave_data *chip = spi_get_ctldata(spi); + struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master); + + if (!chip) + return; + + if (chip->chip_select_num < MAX_CTRL_CS) { + peripheral_free(ssel[spi->master->bus_num] + [chip->chip_select_num-1]); + bfin_spi_cs_disable(drv_data, chip); + } else + gpio_free(chip->cs_gpio); + + kfree(chip); + /* prevent free 'chip' twice */ + spi_set_ctldata(spi, NULL); +} + +static inline int bfin_spi_init_queue(struct bfin_spi_master_data *drv_data) +{ + INIT_LIST_HEAD(&drv_data->queue); + spin_lock_init(&drv_data->lock); + + drv_data->running = false; + drv_data->busy = 0; + + /* init transfer tasklet */ + tasklet_init(&drv_data->pump_transfers, + bfin_spi_pump_transfers, (unsigned long)drv_data); + + /* init messages workqueue */ + INIT_WORK(&drv_data->pump_messages, bfin_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 inline int bfin_spi_start_queue(struct bfin_spi_master_data *drv_data) +{ + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + if (drv_data->running || drv_data->busy) { + spin_unlock_irqrestore(&drv_data->lock, flags); + return -EBUSY; + } + + drv_data->running = 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_spi_stop_queue(struct bfin_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->running = 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_spi_destroy_queue(struct bfin_spi_master_data *drv_data) +{ + int status; + + status = bfin_spi_stop_queue(drv_data); + if (status != 0) + return status; + + destroy_workqueue(drv_data->workqueue); + + return 0; +} + +static int __init bfin_spi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct bfin5xx_spi_master *platform_info; + struct spi_master *master; + struct bfin_spi_master_data *drv_data; + struct resource *res; + int status = 0; + + platform_info = dev->platform_data; + + /* Allocate master with space for drv_data */ + master = spi_alloc_master(dev, sizeof(*drv_data)); + if (!master) { + dev_err(&pdev->dev, "can not alloc spi_master\n"); + return -ENOMEM; + } + + drv_data = spi_master_get_devdata(master); + drv_data->master = master; + drv_data->master_info = platform_info; + drv_data->pdev = pdev; + drv_data->pin_req = platform_info->pin_req; + + /* the spi->mode bits supported by this driver: */ + 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_spi_cleanup; + master->setup = bfin_spi_setup; + master->transfer = bfin_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_base = ioremap(res->start, resource_size(res)); + if (drv_data->regs_base == NULL) { + dev_err(dev, "Cannot map IO\n"); + status = -ENXIO; + goto out_error_ioremap; + } + + res = platform_get_resource(pdev, IORESOURCE_DMA, 0); + if (res == NULL) { + dev_err(dev, "No DMA channel specified\n"); + status = -ENOENT; + goto out_error_free_io; + } + drv_data->dma_channel = res->start; + + drv_data->spi_irq = platform_get_irq(pdev, 0); + if (drv_data->spi_irq < 0) { + dev_err(dev, "No spi pio irq specified\n"); + status = -ENOENT; + goto out_error_free_io; + } + + /* Initial and start queue */ + status = bfin_spi_init_queue(drv_data); + if (status != 0) { + dev_err(dev, "problem initializing queue\n"); + goto out_error_queue_alloc; + } + + status = bfin_spi_start_queue(drv_data); + if (status != 0) { + dev_err(dev, "problem starting queue\n"); + goto out_error_queue_alloc; + } + + status = peripheral_request_list(drv_data->pin_req, DRV_NAME); + if (status != 0) { + dev_err(&pdev->dev, ": Requesting Peripherals failed\n"); + goto out_error_queue_alloc; + } + + /* Reset SPI registers. If these registers were used by the boot loader, + * the sky may fall on your head if you enable the dma controller. + */ + write_CTRL(drv_data, BIT_CTL_CPHA | BIT_CTL_MASTER); + write_FLAG(drv_data, 0xFF00); + + /* Register with the SPI framework */ + platform_set_drvdata(pdev, drv_data); + status = spi_register_master(master); + if (status != 0) { + dev_err(dev, "problem registering spi master\n"); + goto out_error_queue_alloc; + } + + dev_info(dev, "%s, Version %s, regs_base@%p, dma channel@%d\n", + DRV_DESC, DRV_VERSION, drv_data->regs_base, + drv_data->dma_channel); + return status; + +out_error_queue_alloc: + bfin_spi_destroy_queue(drv_data); +out_error_free_io: + iounmap((void *) drv_data->regs_base); +out_error_ioremap: +out_error_get_res: + spi_master_put(master); + + return status; +} + +/* stop hardware and remove the driver */ +static int __devexit bfin_spi_remove(struct platform_device *pdev) +{ + struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev); + int status = 0; + + if (!drv_data) + return 0; + + /* Remove the queue */ + status = bfin_spi_destroy_queue(drv_data); + if (status != 0) + return status; + + /* Disable the SSP at the peripheral and SOC level */ + bfin_spi_disable(drv_data); + + /* Release DMA */ + if (drv_data->master_info->enable_dma) { + if (dma_channel_active(drv_data->dma_channel)) + free_dma(drv_data->dma_channel); + } + + if (drv_data->irq_requested) { + free_irq(drv_data->spi_irq, drv_data); + drv_data->irq_requested = 0; + } + + /* 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_spi_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev); + int status = 0; + + status = bfin_spi_stop_queue(drv_data); + if (status != 0) + return status; + + drv_data->ctrl_reg = read_CTRL(drv_data); + drv_data->flag_reg = read_FLAG(drv_data); + + /* + * reset SPI_CTL and SPI_FLG registers + */ + write_CTRL(drv_data, BIT_CTL_CPHA | BIT_CTL_MASTER); + write_FLAG(drv_data, 0xFF00); + + return 0; +} + +static int bfin_spi_resume(struct platform_device *pdev) +{ + struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev); + int status = 0; + + write_CTRL(drv_data, drv_data->ctrl_reg); + write_FLAG(drv_data, drv_data->flag_reg); + + /* Start the queue running */ + status = bfin_spi_start_queue(drv_data); + if (status != 0) { + dev_err(&pdev->dev, "problem starting queue (%d)\n", status); + return status; + } + + return 0; +} +#else +#define bfin_spi_suspend NULL +#define bfin_spi_resume NULL +#endif /* CONFIG_PM */ + +MODULE_ALIAS("platform:bfin-spi"); +static struct platform_driver bfin_spi_driver = { + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, + .suspend = bfin_spi_suspend, + .resume = bfin_spi_resume, + .remove = __devexit_p(bfin_spi_remove), +}; + +static int __init bfin_spi_init(void) +{ + return platform_driver_probe(&bfin_spi_driver, bfin_spi_probe); +} +subsys_initcall(bfin_spi_init); + +static void __exit bfin_spi_exit(void) +{ + platform_driver_unregister(&bfin_spi_driver); +} +module_exit(bfin_spi_exit); |
