diff options
Diffstat (limited to 'drivers/spi/spi_bfin5xx.c')
| -rw-r--r-- | drivers/spi/spi_bfin5xx.c | 1421 |
1 files changed, 0 insertions, 1421 deletions
diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c deleted file mode 100644 index d853fceb6bf..00000000000 --- a/drivers/spi/spi_bfin5xx.c +++ /dev/null @@ -1,1421 +0,0 @@ -/* - * Blackfin On-Chip SPI Driver - * - * Copyright 2004-2007 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/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> - -#define DRV_NAME "bfin-spi" -#define DRV_AUTHOR "Bryan Wu, Luke Yang" -#define DRV_DESC "Blackfin BF5xx on-chip SPI Controller Driver" -#define DRV_VERSION "1.0" - -MODULE_AUTHOR(DRV_AUTHOR); -MODULE_DESCRIPTION(DRV_DESC); -MODULE_LICENSE("GPL"); - -#define IS_DMA_ALIGNED(x) (((u32)(x)&0x07) == 0) - -#define START_STATE ((void *)0) -#define RUNNING_STATE ((void *)1) -#define DONE_STATE ((void *)2) -#define ERROR_STATE ((void *)-1) -#define QUEUE_RUNNING 0 -#define QUEUE_STOPPED 1 - -struct driver_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; - int run; - - /* Message Transfer pump */ - struct tasklet_struct pump_transfers; - - /* Current message transfer state info */ - struct spi_message *cur_msg; - struct spi_transfer *cur_transfer; - struct chip_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; - - size_t rx_map_len; - size_t tx_map_len; - u8 n_bytes; - int cs_change; - void (*write) (struct driver_data *); - void (*read) (struct driver_data *); - void (*duplex) (struct driver_data *); -}; - -struct chip_data { - u16 ctl_reg; - u16 baud; - u16 flag; - - u8 chip_select_num; - u8 n_bytes; - u8 width; /* 0 or 1 */ - u8 enable_dma; - u8 bits_per_word; /* 8 or 16 */ - u8 cs_change_per_word; - u16 cs_chg_udelay; /* Some devices require > 255usec delay */ - void (*write) (struct driver_data *); - void (*read) (struct driver_data *); - void (*duplex) (struct driver_data *); -}; - -#define DEFINE_SPI_REG(reg, off) \ -static inline u16 read_##reg(struct driver_data *drv_data) \ - { return bfin_read16(drv_data->regs_base + off); } \ -static inline void write_##reg(struct driver_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 driver_data *drv_data) -{ - u16 cr; - - cr = read_CTRL(drv_data); - write_CTRL(drv_data, (cr | BIT_CTL_ENABLE)); -} - -static void bfin_spi_disable(struct driver_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++; - - return spi_baud; -} - -static int flush(struct driver_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 cs_active(struct driver_data *drv_data, struct chip_data *chip) -{ - u16 flag = read_FLAG(drv_data); - - flag |= chip->flag; - flag &= ~(chip->flag << 8); - - write_FLAG(drv_data, flag); -} - -static void cs_deactive(struct driver_data *drv_data, struct chip_data *chip) -{ - u16 flag = read_FLAG(drv_data); - - flag |= (chip->flag << 8); - - write_FLAG(drv_data, flag); - - /* Move delay here for consistency */ - if (chip->cs_chg_udelay) - udelay(chip->cs_chg_udelay); -} - -#define MAX_SPI_SSEL 7 - -/* stop controller and re-config current chip*/ -static void restore_state(struct driver_data *drv_data) -{ - struct chip_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"); - - /* Load the registers */ - write_CTRL(drv_data, chip->ctl_reg); - write_BAUD(drv_data, chip->baud); - - bfin_spi_enable(drv_data); - cs_active(drv_data, chip); -} - -/* used to kick off transfer in rx mode */ -static unsigned short dummy_read(struct driver_data *drv_data) -{ - unsigned short tmp; - tmp = read_RDBR(drv_data); - return tmp; -} - -static void null_writer(struct driver_data *drv_data) -{ - u8 n_bytes = drv_data->n_bytes; - - while (drv_data->tx < drv_data->tx_end) { - write_TDBR(drv_data, 0); - while ((read_STAT(drv_data) & BIT_STAT_TXS)) - cpu_relax(); - drv_data->tx += n_bytes; - } -} - -static void null_reader(struct driver_data *drv_data) -{ - u8 n_bytes = drv_data->n_bytes; - dummy_read(drv_data); - - while (drv_data->rx < drv_data->rx_end) { - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - dummy_read(drv_data); - drv_data->rx += n_bytes; - } -} - -static void u8_writer(struct driver_data *drv_data) -{ - dev_dbg(&drv_data->pdev->dev, - "cr8-s is 0x%x\n", read_STAT(drv_data)); - - while (drv_data->tx < drv_data->tx_end) { - write_TDBR(drv_data, (*(u8 *) (drv_data->tx))); - while (read_STAT(drv_data) & BIT_STAT_TXS) - cpu_relax(); - ++drv_data->tx; - } - - /* poll for SPI completion before return */ - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); -} - -static void u8_cs_chg_writer(struct driver_data *drv_data) -{ - struct chip_data *chip = drv_data->cur_chip; - - while (drv_data->tx < drv_data->tx_end) { - cs_active(drv_data, chip); - - write_TDBR(drv_data, (*(u8 *) (drv_data->tx))); - while (read_STAT(drv_data) & BIT_STAT_TXS) - cpu_relax(); - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - - cs_deactive(drv_data, chip); - - ++drv_data->tx; - } -} - -static void u8_reader(struct driver_data *drv_data) -{ - dev_dbg(&drv_data->pdev->dev, - "cr-8 is 0x%x\n", read_STAT(drv_data)); - - /* poll for SPI completion before start */ - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - - /* clear TDBR buffer before read(else it will be shifted out) */ - write_TDBR(drv_data, 0xFFFF); - - dummy_read(drv_data); - - while (drv_data->rx < drv_data->rx_end - 1) { - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u8 *) (drv_data->rx) = read_RDBR(drv_data); - ++drv_data->rx; - } - - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u8 *) (drv_data->rx) = read_SHAW(drv_data); - ++drv_data->rx; -} - -static void u8_cs_chg_reader(struct driver_data *drv_data) -{ - struct chip_data *chip = drv_data->cur_chip; - - while (drv_data->rx < drv_data->rx_end) { - cs_active(drv_data, chip); - read_RDBR(drv_data); /* kick off */ - - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - - *(u8 *) (drv_data->rx) = read_SHAW(drv_data); - cs_deactive(drv_data, chip); - - ++drv_data->rx; - } -} - -static void u8_duplex(struct driver_data *drv_data) -{ - /* in duplex mode, clk is triggered by writing of TDBR */ - while (drv_data->rx < drv_data->rx_end) { - write_TDBR(drv_data, (*(u8 *) (drv_data->tx))); - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u8 *) (drv_data->rx) = read_RDBR(drv_data); - ++drv_data->rx; - ++drv_data->tx; - } -} - -static void u8_cs_chg_duplex(struct driver_data *drv_data) -{ - struct chip_data *chip = drv_data->cur_chip; - - while (drv_data->rx < drv_data->rx_end) { - cs_active(drv_data, chip); - - write_TDBR(drv_data, (*(u8 *) (drv_data->tx))); - - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u8 *) (drv_data->rx) = read_RDBR(drv_data); - - cs_deactive(drv_data, chip); - - ++drv_data->rx; - ++drv_data->tx; - } -} - -static void u16_writer(struct driver_data *drv_data) -{ - dev_dbg(&drv_data->pdev->dev, - "cr16 is 0x%x\n", read_STAT(drv_data)); - - while (drv_data->tx < drv_data->tx_end) { - write_TDBR(drv_data, (*(u16 *) (drv_data->tx))); - while ((read_STAT(drv_data) & BIT_STAT_TXS)) - cpu_relax(); - drv_data->tx += 2; - } - - /* poll for SPI completion before return */ - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); -} - -static void u16_cs_chg_writer(struct driver_data *drv_data) -{ - struct chip_data *chip = drv_data->cur_chip; - - while (drv_data->tx < drv_data->tx_end) { - cs_active(drv_data, chip); - - write_TDBR(drv_data, (*(u16 *) (drv_data->tx))); - while ((read_STAT(drv_data) & BIT_STAT_TXS)) - cpu_relax(); - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - - cs_deactive(drv_data, chip); - - drv_data->tx += 2; - } -} - -static void u16_reader(struct driver_data *drv_data) -{ - dev_dbg(&drv_data->pdev->dev, - "cr-16 is 0x%x\n", read_STAT(drv_data)); - - /* poll for SPI completion before start */ - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - - /* clear TDBR buffer before read(else it will be shifted out) */ - write_TDBR(drv_data, 0xFFFF); - - dummy_read(drv_data); - - while (drv_data->rx < (drv_data->rx_end - 2)) { - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u16 *) (drv_data->rx) = read_RDBR(drv_data); - drv_data->rx += 2; - } - - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u16 *) (drv_data->rx) = read_SHAW(drv_data); - drv_data->rx += 2; -} - -static void u16_cs_chg_reader(struct driver_data *drv_data) -{ - struct chip_data *chip = drv_data->cur_chip; - - /* poll for SPI completion before start */ - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - - /* clear TDBR buffer before read(else it will be shifted out) */ - write_TDBR(drv_data, 0xFFFF); - - cs_active(drv_data, chip); - dummy_read(drv_data); - - while (drv_data->rx < drv_data->rx_end - 2) { - cs_deactive(drv_data, chip); - - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - cs_active(drv_data, chip); - *(u16 *) (drv_data->rx) = read_RDBR(drv_data); - drv_data->rx += 2; - } - cs_deactive(drv_data, chip); - - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u16 *) (drv_data->rx) = read_SHAW(drv_data); - drv_data->rx += 2; -} - -static void u16_duplex(struct driver_data *drv_data) -{ - /* in duplex mode, clk is triggered by writing of TDBR */ - while (drv_data->tx < drv_data->tx_end) { - write_TDBR(drv_data, (*(u16 *) (drv_data->tx))); - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u16 *) (drv_data->rx) = read_RDBR(drv_data); - drv_data->rx += 2; - drv_data->tx += 2; - } -} - -static void u16_cs_chg_duplex(struct driver_data *drv_data) -{ - struct chip_data *chip = drv_data->cur_chip; - - while (drv_data->tx < drv_data->tx_end) { - cs_active(drv_data, chip); - - write_TDBR(drv_data, (*(u16 *) (drv_data->tx))); - while (!(read_STAT(drv_data) & BIT_STAT_SPIF)) - cpu_relax(); - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) - cpu_relax(); - *(u16 *) (drv_data->rx) = read_RDBR(drv_data); - - cs_deactive(drv_data, chip); - - drv_data->rx += 2; - drv_data->tx += 2; - } -} - -/* test if ther is more transfer to be done */ -static void *next_transfer(struct driver_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 giveback(struct driver_data *drv_data) -{ - struct chip_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; - - /* disable chip select signal. And not stop spi in autobuffer mode */ - if (drv_data->tx_dma != 0xFFFF) { - cs_deactive(drv_data, chip); - bfin_spi_disable(drv_data); - } - - if (!drv_data->cs_change) - cs_deactive(drv_data, chip); - - if (msg->complete) - msg->complete(msg->context); -} - -static irqreturn_t dma_irq_handler(int irq, void *dev_id) -{ - struct driver_data *drv_data = dev_id; - struct chip_data *chip = drv_data->cur_chip; - struct spi_message *msg = drv_data->cur_msg; - - dev_dbg(&drv_data->pdev->dev, "in dma_irq_handler\n"); - clear_dma_irqstat(drv_data->dma_channel); - - /* Wait for DMA to complete */ - while (get_dma_curr_irqstat(drv_data->dma_channel) & DMA_RUN) - cpu_relax(); - - /* - * 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) & TXS) || - (read_STAT(drv_data) & TXS)) - cpu_relax(); - } - - while (!(read_STAT(drv_data) & SPIF)) - cpu_relax(); - - msg->actual_length += drv_data->len_in_bytes; - - if (drv_data->cs_change) - cs_deactive(drv_data, chip); - - /* Move to next transfer */ - msg->state = 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(drv_data->dma_channel); - - return IRQ_HANDLED; -} - -static void pump_transfers(unsigned long data) -{ - struct driver_data *drv_data = (struct driver_data *)data; - struct spi_message *message = NULL; - struct spi_transfer *transfer = NULL; - struct spi_transfer *previous = NULL; - struct chip_data *chip = NULL; - u8 width; - u16 cr, dma_width, dma_config; - u32 tranf_success = 1; - - /* 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) { - message->status = -EIO; - giveback(drv_data); - return; - } - - /* Handle end of message */ - if (message->state == DONE_STATE) { - message->status = 0; - giveback(drv_data); - return; - } - - /* Delay if requested at end of transfer */ - if (message->state == RUNNING_STATE) { - previous = list_entry(transfer->transfer_list.prev, - struct spi_transfer, transfer_list); - if (previous->delay_usecs) - udelay(previous->delay_usecs); - } - - /* Setup the transfer state based on the type of transfer */ - if (flush(drv_data) == 0) { - dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n"); - message->status = -EIO; - giveback(drv_data); - 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) { - 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 */ - switch (transfer->bits_per_word) { - case 8: - drv_data->n_bytes = 1; - width = CFG_SPI_WORDSIZE8; - drv_data->read = chip->cs_change_per_word ? - u8_cs_chg_reader : u8_reader; - drv_data->write = chip->cs_change_per_word ? - u8_cs_chg_writer : u8_writer; - drv_data->duplex = chip->cs_change_per_word ? - u8_cs_chg_duplex : u8_duplex; - break; - - case 16: - drv_data->n_bytes = 2; - width = CFG_SPI_WORDSIZE16; - drv_data->read = chip->cs_change_per_word ? - u16_cs_chg_reader : u16_reader; - drv_data->write = chip->cs_change_per_word ? - u16_cs_chg_writer : u16_writer; - drv_data->duplex = chip->cs_change_per_word ? - u16_cs_chg_duplex : u16_duplex; - break; - - default: - /* No change, the same as default setting */ - drv_data->n_bytes = chip->n_bytes; - width = chip->width; - drv_data->write = drv_data->tx ? chip->write : null_writer; - drv_data->read = drv_data->rx ? chip->read : null_reader; - drv_data->duplex = chip->duplex ? chip->duplex : null_writer; - break; - } - cr = (read_CTRL(drv_data) & (~BIT_CTL_TIMOD)); - cr |= (width << 8); - write_CTRL(drv_data, cr); - - if (width == CFG_SPI_WORDSIZE16) { - drv_data->len = (transfer->len) >> 1; - } else { - drv_data->len = transfer->len; - } - dev_dbg(&drv_data->pdev->dev, "transfer: ", - "drv_data->write is %p, chip->write is %p, null_wr is %p\n", - drv_data->write, chip->write, null_writer); - - /* speed and width has been set on per message */ - 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); - cr = (read_CTRL(drv_data) & (~BIT_CTL_TIMOD)); - cs_active(drv_data, chip); - - dev_dbg(&drv_data->pdev->dev, - "now pumping a transfer: width is %d, len is %d\n", - width, transfer->len); - - /* - * Try to map dma buffer and do a dma transfer if - * successful use different way to r/w according to - * drv_data->cur_chip->enable_dma - */ - if (drv_data->cur_chip->enable_dma && drv_data->len > 6) { - - disable_dma(drv_data->dma_channel); - clear_dma_irqstat(drv_data->dma_channel); - bfin_spi_disable(drv_data); - - /* config dma channel */ - dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n"); - if (width == CFG_SPI_WORDSIZE16) { - set_dma_x_count(drv_data->dma_channel, drv_data->len); - set_dma_x_modify(drv_data->dma_channel, 2); - dma_width = WDSIZE_16; - } else { - set_dma_x_count(drv_data->dma_channel, drv_data->len); - 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 | CFG_SPI_DMAWRITE | BIT_CTL_ENABLE)); - - /* just return here, there can only be one transfer - * in this mode - */ - message->status = 0; - giveback(drv_data); - return; - } - - /* In dma mode, rx or tx must be NULL in one transfer */ - if (drv_data->rx != NULL) { - /* set transfer mode, and enable SPI */ - dev_dbg(&drv_data->pdev->dev, "doing DMA in.\n"); - - /* clear tx reg soformer data is not shifted out */ - write_TDBR(drv_data, 0xFFFF); - - set_dma_x_count(drv_data->dma_channel, drv_data->len); - - /* start dma */ - dma_enable_irq(drv_data->dma_channel); - dma_config = (WNR | 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->rx); - enable_dma(drv_data->dma_channel); - - /* start SPI transfer */ - write_CTRL(drv_data, - (cr | CFG_SPI_DMAREAD | BIT_CTL_ENABLE)); - - } else if (drv_data->tx != NULL) { - dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n"); - - /* start dma */ - dma_enable_irq(drv_data->dma_channel); - dma_config = (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 | CFG_SPI_DMAWRITE | BIT_CTL_ENABLE)); - } - } else { - /* IO mode write then read */ - dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n"); - - if (drv_data->tx != NULL && drv_data->rx != NULL) { - /* 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); - - /* set SPI transfer mode */ - write_CTRL(drv_data, (cr | CFG_SPI_WRITE)); - - drv_data->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); - - /* set SPI transfer mode */ - write_CTRL(drv_data, (cr | CFG_SPI_WRITE)); - - drv_data->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); - - /* set SPI transfer mode */ - write_CTRL(drv_data, (cr | CFG_SPI_READ)); - - drv_data->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 transfered */ - message->actual_length += drv_data->len; - - /* Move to next transfer of this msg */ - message->state = next_transfer(drv_data); - } - - /* Schedule next transfer tasklet */ - tasklet_schedule(&drv_data->pump_transfers); - - } -} - -/* pop a msg from queue and kick off real transfer */ -static void pump_messages(struct work_struct *work) -{ - struct driver_data *drv_data; - unsigned long flags; - - drv_data = container_of(work, struct driver_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 == QUEUE_STOPPED) { - /* 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); - 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 transfer(struct spi_device *spi, struct spi_message *msg) -{ - struct driver_data *drv_data = spi_master_get_devdata(spi->master); - unsigned long flags; - - spin_lock_irqsave(&drv_data->lock, flags); - - if (drv_data->run == QUEUE_STOPPED) { - 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 == QUEUE_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[3][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}, -}; - -/* first setup for new devices */ -static int setup(struct spi_device *spi) -{ - struct bfin5xx_spi_chip *chip_info = NULL; - struct chip_data *chip; - struct driver_data *drv_data = spi_master_get_devdata(spi->master); - u8 spi_flg; - - /* Abort device setup if requested features are not supported */ - if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) { - dev_err(&spi->dev, "requested mode not fully supported\n"); - return -EINVAL; - } - - /* Zero (the default) here means 8 bits */ - if (!spi->bits_per_word) - spi->bits_per_word = 8; - - if (spi->bits_per_word != 8 && spi->bits_per_word != 16) - return -EINVAL; - - /* Only alloc (or use chip_info) on first setup */ - chip = spi_get_ctldata(spi); - if (chip == NULL) { - chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); - if (!chip) - return -ENOMEM; - - chip->enable_dma = 0; - chip_info = spi->controller_data; - } - - /* 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 TIMOD. - * Not sure if a user actually needs/uses any of these, - * but let's assume (for now) they do. - */ - if (chip_info->ctl_reg & (SPE|MSTR|CPOL|CPHA|LSBF|SIZE)) { - dev_err(&spi->dev, "do not set bits in ctl_reg " - "that the SPI framework manages\n"); - return -EINVAL; - } - - chip->enable_dma = chip_info->enable_dma != 0 - && drv_data->master_info->enable_dma; - chip->ctl_reg = chip_info->ctl_reg; - chip->bits_per_word = chip_info->bits_per_word; - chip->cs_change_per_word = chip_info->cs_change_per_word; - chip->cs_chg_udelay = chip_info->cs_chg_udelay; - } - - /* translate common spi framework into our register */ - if (spi->mode & SPI_CPOL) - chip->ctl_reg |= CPOL; - if (spi->mode & SPI_CPHA) - chip->ctl_reg |= CPHA; - if (spi->mode & SPI_LSB_FIRST) - chip->ctl_reg |= LSBF; - /* we dont support running in slave mode (yet?) */ - chip->ctl_reg |= MSTR; - - /* - * 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 */ - if (request_dma(drv_data->dma_channel, "BF53x_SPI_DMA") < 0) { - dev_dbg(&spi->dev, - "Unable to request BlackFin SPI DMA channel\n"); - return -ENODEV; - } - if (set_dma_callback(drv_data->dma_channel, - (void *)dma_irq_handler, drv_data) < 0) { - dev_dbg(&spi->dev, "Unable to set dma callback\n"); - return -EPERM; - } - dma_disable_irq(drv_data->dma_channel); - drv_data->dma_requested = 1; - } - - /* - * 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); - spi_flg = ~(1 << (spi->chip_select)); - chip->flag = ((u16) spi_flg << 8) | (1 << (spi->chip_select)); - chip->chip_select_num = spi->chip_select; - - switch (chip->bits_per_word) { - case 8: - chip->n_bytes = 1; - chip->width = CFG_SPI_WORDSIZE8; - chip->read = chip->cs_change_per_word ? - u8_cs_chg_reader : u8_reader; - chip->write = chip->cs_change_per_word ? - u8_cs_chg_writer : u8_writer; - chip->duplex = chip->cs_change_per_word ? - u8_cs_chg_duplex : u8_duplex; - break; - - case 16: - chip->n_bytes = 2; - chip->width = CFG_SPI_WORDSIZE16; - chip->read = chip->cs_change_per_word ? - u16_cs_chg_reader : u16_reader; - chip->write = chip->cs_change_per_word ? - u16_cs_chg_writer : u16_writer; - chip->duplex = chip->cs_change_per_word ? - u16_cs_chg_duplex : u16_duplex; - break; - - default: - dev_err(&spi->dev, "%d bits_per_word is not supported\n", - chip->bits_per_word); - kfree(chip); - return -ENODEV; - } - - dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d\n", - spi->modalias, chip->width, 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 > 0) - && (chip->chip_select_num <= spi->master->num_chipselect)) - peripheral_request(ssel[spi->master->bus_num] - [chip->chip_select_num-1], spi->modalias); - - cs_deactive(drv_data, chip); - - return 0; -} - -/* - * callback for spi framework. - * clean driver specific data - */ -static void cleanup(struct spi_device *spi) -{ - struct chip_data *chip = spi_get_ctldata(spi); - - if ((chip->chip_select_num > 0) - && (chip->chip_select_num <= spi->master->num_chipselect)) - peripheral_free(ssel[spi->master->bus_num] - [chip->chip_select_num-1]); - - kfree(chip); -} - -static inline int init_queue(struct driver_data *drv_data) -{ - INIT_LIST_HEAD(&drv_data->queue); - spin_lock_init(&drv_data->lock); - - drv_data->run = QUEUE_STOPPED; - drv_data->busy = 0; - - /* init transfer tasklet */ - tasklet_init(&drv_data->pump_transfers, - pump_transfers, (unsigned long)drv_data); - - /* init messages workqueue */ - INIT_WORK(&drv_data->pump_messages, pump_messages); - drv_data->workqueue = - create_singlethread_workqueue(drv_data->master->dev.parent->bus_id); - if (drv_data->workqueue == NULL) - return -EBUSY; - - return 0; -} - -static inline int start_queue(struct driver_data *drv_data) -{ - unsigned long flags; - - spin_lock_irqsave(&drv_data->lock, flags); - - if (drv_data->run == QUEUE_RUNNING || drv_data->busy) { - spin_unlock_irqrestore(&drv_data->lock, flags); - return -EBUSY; - } - - drv_data->run = QUEUE_RUNNING; - 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 stop_queue(struct driver_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 = QUEUE_STOPPED; - 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 destroy_queue(struct driver_data *drv_data) -{ - int status; - - status = stop_queue(drv_data); - if (status != 0) - return status; - - destroy_workqueue(drv_data->workqueue); - - return 0; -} - -static int __init bfin5xx_spi_probe(struct platform_device *pdev) -{ - struct device *dev = &pdev->dev; - struct bfin5xx_spi_master *platform_info; - struct spi_master *master; - struct driver_data *drv_data = 0; - struct resource *res; - int status = 0; - - platform_info = dev->platform_data; - - /* Allocate master with space for drv_data */ - master = spi_alloc_master(dev, sizeof(struct driver_data) + 16); - 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; - - master->bus_num = pdev->id; - master->num_chipselect = platform_info->num_chipselect; - master->cleanup = cleanup; - master->setup = setup; - master->transfer = 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, (res->end - res->start + 1)); - if (drv_data->regs_base == NULL) { - dev_err(dev, "Cannot map IO\n"); - status = -ENXIO; - goto out_error_ioremap; - } - - drv_data->dma_channel = platform_get_irq(pdev, 0); - if (drv_data->dma_channel < 0) { - dev_err(dev, "No DMA channel specified\n"); - status = -ENOENT; - goto out_error_no_dma_ch; - } - - /* Initial and start queue */ - status = init_queue(drv_data); - if (status != 0) { - dev_err(dev, "problem initializing queue\n"); - goto out_error_queue_alloc; - } - - status = start_queue(drv_data); - if (status != 0) { - dev_err(dev, "problem starting queue\n"); - goto out_error_queue_alloc; - } - - /* 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; - } - - status = peripheral_request_list(drv_data->pin_req, DRV_NAME); - if (status != 0) { - dev_err(&pdev->dev, ": Requesting Peripherals failed\n"); - goto out_error; - } - - 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: - destroy_queue(drv_data); -out_error_no_dma_ch: - iounmap((void *) drv_data->regs_base); -out_error_ioremap: -out_error_get_res: -out_error: - spi_master_put(master); - - return status; -} - -/* stop hardware and remove the driver */ -static int __devexit bfin5xx_spi_remove(struct platform_device *pdev) -{ - struct driver_data *drv_data = platform_get_drvdata(pdev); - int status = 0; - - if (!drv_data) - return 0; - - /* Remove the queue */ - status = 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); - } - - /* 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 bfin5xx_spi_suspend(struct platform_device *pdev, pm_message_t state) -{ - struct driver_data *drv_data = platform_get_drvdata(pdev); - int status = 0; - - status = stop_queue(drv_data); - if (status != 0) - return status; - - /* stop hardware */ - bfin_spi_disable(drv_data); - - return 0; -} - -static int bfin5xx_spi_resume(struct platform_device *pdev) -{ - struct driver_data *drv_data = platform_get_drvdata(pdev); - int status = 0; - - /* Enable the SPI interface */ - bfin_spi_enable(drv_data); - - /* Start the queue running */ - status = start_queue(drv_data); - if (status != 0) { - dev_err(&pdev->dev, "problem starting queue (%d)\n", status); - return status; - } - - return 0; -} -#else -#define bfin5xx_spi_suspend NULL -#define bfin5xx_spi_resume NULL -#endif /* CONFIG_PM */ - -MODULE_ALIAS("bfin-spi-master"); /* for platform bus hotplug */ -static struct platform_driver bfin5xx_spi_driver = { - .driver = { - .name = DRV_NAME, - .owner = THIS_MODULE, - }, - .suspend = bfin5xx_spi_suspend, - .resume = bfin5xx_spi_resume, - .remove = __devexit_p(bfin5xx_spi_remove), -}; - -static int __init bfin5xx_spi_init(void) -{ - return platform_driver_probe(&bfin5xx_spi_driver, bfin5xx_spi_probe); -} -module_init(bfin5xx_spi_init); - -static void __exit bfin5xx_spi_exit(void) -{ - platform_driver_unregister(&bfin5xx_spi_driver); -} -module_exit(bfin5xx_spi_exit); |