aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-bfin5xx.c
diff options
context:
space:
mode:
authorGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
committerGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
commitca632f556697d45d67ed5cada7cedf3ddfe0db4b (patch)
treef393534b929abb32813ea5c495f1ac6d93a10d1d /drivers/spi/spi-bfin5xx.c
parent8c99268431a117207a89be5167ecd69429fd4bda (diff)
downloadlinaro-lsk-ca632f556697d45d67ed5cada7cedf3ddfe0db4b.tar.gz
spi: reorganize drivers
Sort the SPI makefile and enforce the naming convention spi_*.c for spi drivers. This change also rolls the contents of atmel_spi.h into the .c file since there is only one user of that particular include file. v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be be the predominant pattern for subsystem prefixes. - Clean up filenames in Kconfig and header comment blocks Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/spi/spi-bfin5xx.c')
-rw-r--r--drivers/spi/spi-bfin5xx.c1530
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 00000000000..f706dba165c
--- /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);