3a44623d5e
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Mark Brown <broonie@linaro.org>
931 lines
23 KiB
C
931 lines
23 KiB
C
/*
|
|
* SPI bus via the Blackfin SPORT peripheral
|
|
*
|
|
* Enter bugs at http://blackfin.uclinux.org/
|
|
*
|
|
* Copyright 2009-2011 Analog Devices Inc.
|
|
*
|
|
* Licensed under the GPL-2 or later.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/device.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/io.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/workqueue.h>
|
|
|
|
#include <asm/portmux.h>
|
|
#include <asm/bfin5xx_spi.h>
|
|
#include <asm/blackfin.h>
|
|
#include <asm/bfin_sport.h>
|
|
#include <asm/cacheflush.h>
|
|
|
|
#define DRV_NAME "bfin-sport-spi"
|
|
#define DRV_DESC "SPI bus via the Blackfin SPORT"
|
|
|
|
MODULE_AUTHOR("Cliff Cai");
|
|
MODULE_DESCRIPTION(DRV_DESC);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:bfin-sport-spi");
|
|
|
|
enum bfin_sport_spi_state {
|
|
START_STATE,
|
|
RUNNING_STATE,
|
|
DONE_STATE,
|
|
ERROR_STATE,
|
|
};
|
|
|
|
struct bfin_sport_spi_master_data;
|
|
|
|
struct bfin_sport_transfer_ops {
|
|
void (*write) (struct bfin_sport_spi_master_data *);
|
|
void (*read) (struct bfin_sport_spi_master_data *);
|
|
void (*duplex) (struct bfin_sport_spi_master_data *);
|
|
};
|
|
|
|
struct bfin_sport_spi_master_data {
|
|
/* Driver model hookup */
|
|
struct device *dev;
|
|
|
|
/* SPI framework hookup */
|
|
struct spi_master *master;
|
|
|
|
/* Regs base of SPI controller */
|
|
struct sport_register __iomem *regs;
|
|
int err_irq;
|
|
|
|
/* Pin request list */
|
|
u16 *pin_req;
|
|
|
|
/* Driver message queue */
|
|
struct workqueue_struct *workqueue;
|
|
struct work_struct pump_messages;
|
|
spinlock_t lock;
|
|
struct list_head queue;
|
|
int busy;
|
|
bool run;
|
|
|
|
/* Message Transfer pump */
|
|
struct tasklet_struct pump_transfers;
|
|
|
|
/* Current message transfer state info */
|
|
enum bfin_sport_spi_state state;
|
|
struct spi_message *cur_msg;
|
|
struct spi_transfer *cur_transfer;
|
|
struct bfin_sport_spi_slave_data *cur_chip;
|
|
union {
|
|
void *tx;
|
|
u8 *tx8;
|
|
u16 *tx16;
|
|
};
|
|
void *tx_end;
|
|
union {
|
|
void *rx;
|
|
u8 *rx8;
|
|
u16 *rx16;
|
|
};
|
|
void *rx_end;
|
|
|
|
int cs_change;
|
|
struct bfin_sport_transfer_ops *ops;
|
|
};
|
|
|
|
struct bfin_sport_spi_slave_data {
|
|
u16 ctl_reg;
|
|
u16 baud;
|
|
u16 cs_chg_udelay; /* Some devices require > 255usec delay */
|
|
u32 cs_gpio;
|
|
u16 idle_tx_val;
|
|
struct bfin_sport_transfer_ops *ops;
|
|
};
|
|
|
|
static void
|
|
bfin_sport_spi_enable(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
bfin_write_or(&drv_data->regs->tcr1, TSPEN);
|
|
bfin_write_or(&drv_data->regs->rcr1, TSPEN);
|
|
SSYNC();
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_disable(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
bfin_write_and(&drv_data->regs->tcr1, ~TSPEN);
|
|
bfin_write_and(&drv_data->regs->rcr1, ~TSPEN);
|
|
SSYNC();
|
|
}
|
|
|
|
/* Caculate the SPI_BAUD register value based on input HZ */
|
|
static u16
|
|
bfin_sport_hz_to_spi_baud(u32 speed_hz)
|
|
{
|
|
u_long clk, sclk = get_sclk();
|
|
int div = (sclk / (2 * speed_hz)) - 1;
|
|
|
|
if (div < 0)
|
|
div = 0;
|
|
|
|
clk = sclk / (2 * (div + 1));
|
|
|
|
if (clk > speed_hz)
|
|
div++;
|
|
|
|
return div;
|
|
}
|
|
|
|
/* Chip select operation functions for cs_change flag */
|
|
static void
|
|
bfin_sport_spi_cs_active(struct bfin_sport_spi_slave_data *chip)
|
|
{
|
|
gpio_direction_output(chip->cs_gpio, 0);
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_cs_deactive(struct bfin_sport_spi_slave_data *chip)
|
|
{
|
|
gpio_direction_output(chip->cs_gpio, 1);
|
|
/* Move delay here for consistency */
|
|
if (chip->cs_chg_udelay)
|
|
udelay(chip->cs_chg_udelay);
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_stat_poll_complete(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
unsigned long timeout = jiffies + HZ;
|
|
while (!(bfin_read(&drv_data->regs->stat) & RXNE)) {
|
|
if (!time_before(jiffies, timeout))
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_u8_writer(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
u16 dummy;
|
|
|
|
while (drv_data->tx < drv_data->tx_end) {
|
|
bfin_write(&drv_data->regs->tx16, *drv_data->tx8++);
|
|
bfin_sport_spi_stat_poll_complete(drv_data);
|
|
dummy = bfin_read(&drv_data->regs->rx16);
|
|
}
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_u8_reader(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
u16 tx_val = drv_data->cur_chip->idle_tx_val;
|
|
|
|
while (drv_data->rx < drv_data->rx_end) {
|
|
bfin_write(&drv_data->regs->tx16, tx_val);
|
|
bfin_sport_spi_stat_poll_complete(drv_data);
|
|
*drv_data->rx8++ = bfin_read(&drv_data->regs->rx16);
|
|
}
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_u8_duplex(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
while (drv_data->rx < drv_data->rx_end) {
|
|
bfin_write(&drv_data->regs->tx16, *drv_data->tx8++);
|
|
bfin_sport_spi_stat_poll_complete(drv_data);
|
|
*drv_data->rx8++ = bfin_read(&drv_data->regs->rx16);
|
|
}
|
|
}
|
|
|
|
static struct bfin_sport_transfer_ops bfin_sport_transfer_ops_u8 = {
|
|
.write = bfin_sport_spi_u8_writer,
|
|
.read = bfin_sport_spi_u8_reader,
|
|
.duplex = bfin_sport_spi_u8_duplex,
|
|
};
|
|
|
|
static void
|
|
bfin_sport_spi_u16_writer(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
u16 dummy;
|
|
|
|
while (drv_data->tx < drv_data->tx_end) {
|
|
bfin_write(&drv_data->regs->tx16, *drv_data->tx16++);
|
|
bfin_sport_spi_stat_poll_complete(drv_data);
|
|
dummy = bfin_read(&drv_data->regs->rx16);
|
|
}
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_u16_reader(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
u16 tx_val = drv_data->cur_chip->idle_tx_val;
|
|
|
|
while (drv_data->rx < drv_data->rx_end) {
|
|
bfin_write(&drv_data->regs->tx16, tx_val);
|
|
bfin_sport_spi_stat_poll_complete(drv_data);
|
|
*drv_data->rx16++ = bfin_read(&drv_data->regs->rx16);
|
|
}
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_u16_duplex(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
while (drv_data->rx < drv_data->rx_end) {
|
|
bfin_write(&drv_data->regs->tx16, *drv_data->tx16++);
|
|
bfin_sport_spi_stat_poll_complete(drv_data);
|
|
*drv_data->rx16++ = bfin_read(&drv_data->regs->rx16);
|
|
}
|
|
}
|
|
|
|
static struct bfin_sport_transfer_ops bfin_sport_transfer_ops_u16 = {
|
|
.write = bfin_sport_spi_u16_writer,
|
|
.read = bfin_sport_spi_u16_reader,
|
|
.duplex = bfin_sport_spi_u16_duplex,
|
|
};
|
|
|
|
/* stop controller and re-config current chip */
|
|
static void
|
|
bfin_sport_spi_restore_state(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip;
|
|
|
|
bfin_sport_spi_disable(drv_data);
|
|
dev_dbg(drv_data->dev, "restoring spi ctl state\n");
|
|
|
|
bfin_write(&drv_data->regs->tcr1, chip->ctl_reg);
|
|
bfin_write(&drv_data->regs->tclkdiv, chip->baud);
|
|
SSYNC();
|
|
|
|
bfin_write(&drv_data->regs->rcr1, chip->ctl_reg & ~(ITCLK | ITFS));
|
|
SSYNC();
|
|
|
|
bfin_sport_spi_cs_active(chip);
|
|
}
|
|
|
|
/* test if there is more transfer to be done */
|
|
static enum bfin_sport_spi_state
|
|
bfin_sport_spi_next_transfer(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
struct spi_message *msg = drv_data->cur_msg;
|
|
struct spi_transfer *trans = drv_data->cur_transfer;
|
|
|
|
/* Move to next transfer */
|
|
if (trans->transfer_list.next != &msg->transfers) {
|
|
drv_data->cur_transfer =
|
|
list_entry(trans->transfer_list.next,
|
|
struct spi_transfer, transfer_list);
|
|
return RUNNING_STATE;
|
|
}
|
|
|
|
return DONE_STATE;
|
|
}
|
|
|
|
/*
|
|
* caller already set message->status;
|
|
* dma and pio irqs are blocked give finished message back
|
|
*/
|
|
static void
|
|
bfin_sport_spi_giveback(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip;
|
|
unsigned long flags;
|
|
struct spi_message *msg;
|
|
|
|
spin_lock_irqsave(&drv_data->lock, flags);
|
|
msg = drv_data->cur_msg;
|
|
drv_data->state = START_STATE;
|
|
drv_data->cur_msg = NULL;
|
|
drv_data->cur_transfer = NULL;
|
|
drv_data->cur_chip = NULL;
|
|
queue_work(drv_data->workqueue, &drv_data->pump_messages);
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
|
|
if (!drv_data->cs_change)
|
|
bfin_sport_spi_cs_deactive(chip);
|
|
|
|
if (msg->complete)
|
|
msg->complete(msg->context);
|
|
}
|
|
|
|
static irqreturn_t
|
|
sport_err_handler(int irq, void *dev_id)
|
|
{
|
|
struct bfin_sport_spi_master_data *drv_data = dev_id;
|
|
u16 status;
|
|
|
|
dev_dbg(drv_data->dev, "%s enter\n", __func__);
|
|
status = bfin_read(&drv_data->regs->stat) & (TOVF | TUVF | ROVF | RUVF);
|
|
|
|
if (status) {
|
|
bfin_write(&drv_data->regs->stat, status);
|
|
SSYNC();
|
|
|
|
bfin_sport_spi_disable(drv_data);
|
|
dev_err(drv_data->dev, "status error:%s%s%s%s\n",
|
|
status & TOVF ? " TOVF" : "",
|
|
status & TUVF ? " TUVF" : "",
|
|
status & ROVF ? " ROVF" : "",
|
|
status & RUVF ? " RUVF" : "");
|
|
}
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static void
|
|
bfin_sport_spi_pump_transfers(unsigned long data)
|
|
{
|
|
struct bfin_sport_spi_master_data *drv_data = (void *)data;
|
|
struct spi_message *message = NULL;
|
|
struct spi_transfer *transfer = NULL;
|
|
struct spi_transfer *previous = NULL;
|
|
struct bfin_sport_spi_slave_data *chip = NULL;
|
|
unsigned int bits_per_word;
|
|
u32 tranf_success = 1;
|
|
u32 transfer_speed;
|
|
u8 full_duplex = 0;
|
|
|
|
/* Get current state information */
|
|
message = drv_data->cur_msg;
|
|
transfer = drv_data->cur_transfer;
|
|
chip = drv_data->cur_chip;
|
|
|
|
if (transfer->speed_hz)
|
|
transfer_speed = bfin_sport_hz_to_spi_baud(transfer->speed_hz);
|
|
else
|
|
transfer_speed = chip->baud;
|
|
bfin_write(&drv_data->regs->tclkdiv, transfer_speed);
|
|
SSYNC();
|
|
|
|
/*
|
|
* if msg is error or done, report it back using complete() callback
|
|
*/
|
|
|
|
/* Handle for abort */
|
|
if (drv_data->state == ERROR_STATE) {
|
|
dev_dbg(drv_data->dev, "transfer: we've hit an error\n");
|
|
message->status = -EIO;
|
|
bfin_sport_spi_giveback(drv_data);
|
|
return;
|
|
}
|
|
|
|
/* Handle end of message */
|
|
if (drv_data->state == DONE_STATE) {
|
|
dev_dbg(drv_data->dev, "transfer: all done!\n");
|
|
message->status = 0;
|
|
bfin_sport_spi_giveback(drv_data);
|
|
return;
|
|
}
|
|
|
|
/* Delay if requested at end of transfer */
|
|
if (drv_data->state == RUNNING_STATE) {
|
|
dev_dbg(drv_data->dev, "transfer: still running ...\n");
|
|
previous = list_entry(transfer->transfer_list.prev,
|
|
struct spi_transfer, transfer_list);
|
|
if (previous->delay_usecs)
|
|
udelay(previous->delay_usecs);
|
|
}
|
|
|
|
if (transfer->len == 0) {
|
|
/* Move to next transfer of this msg */
|
|
drv_data->state = bfin_sport_spi_next_transfer(drv_data);
|
|
/* Schedule next transfer tasklet */
|
|
tasklet_schedule(&drv_data->pump_transfers);
|
|
}
|
|
|
|
if (transfer->tx_buf != NULL) {
|
|
drv_data->tx = (void *)transfer->tx_buf;
|
|
drv_data->tx_end = drv_data->tx + transfer->len;
|
|
dev_dbg(drv_data->dev, "tx_buf is %p, tx_end is %p\n",
|
|
transfer->tx_buf, drv_data->tx_end);
|
|
} else
|
|
drv_data->tx = NULL;
|
|
|
|
if (transfer->rx_buf != NULL) {
|
|
full_duplex = transfer->tx_buf != NULL;
|
|
drv_data->rx = transfer->rx_buf;
|
|
drv_data->rx_end = drv_data->rx + transfer->len;
|
|
dev_dbg(drv_data->dev, "rx_buf is %p, rx_end is %p\n",
|
|
transfer->rx_buf, drv_data->rx_end);
|
|
} else
|
|
drv_data->rx = NULL;
|
|
|
|
drv_data->cs_change = transfer->cs_change;
|
|
|
|
/* Bits per word setup */
|
|
bits_per_word = transfer->bits_per_word;
|
|
if (bits_per_word == 16)
|
|
drv_data->ops = &bfin_sport_transfer_ops_u16;
|
|
else
|
|
drv_data->ops = &bfin_sport_transfer_ops_u8;
|
|
bfin_write(&drv_data->regs->tcr2, bits_per_word - 1);
|
|
bfin_write(&drv_data->regs->tfsdiv, bits_per_word - 1);
|
|
bfin_write(&drv_data->regs->rcr2, bits_per_word - 1);
|
|
|
|
drv_data->state = RUNNING_STATE;
|
|
|
|
if (drv_data->cs_change)
|
|
bfin_sport_spi_cs_active(chip);
|
|
|
|
dev_dbg(drv_data->dev,
|
|
"now pumping a transfer: width is %d, len is %d\n",
|
|
bits_per_word, transfer->len);
|
|
|
|
/* PIO mode write then read */
|
|
dev_dbg(drv_data->dev, "doing IO transfer\n");
|
|
|
|
bfin_sport_spi_enable(drv_data);
|
|
if (full_duplex) {
|
|
/* full duplex mode */
|
|
BUG_ON((drv_data->tx_end - drv_data->tx) !=
|
|
(drv_data->rx_end - drv_data->rx));
|
|
drv_data->ops->duplex(drv_data);
|
|
|
|
if (drv_data->tx != drv_data->tx_end)
|
|
tranf_success = 0;
|
|
} else if (drv_data->tx != NULL) {
|
|
/* write only half duplex */
|
|
|
|
drv_data->ops->write(drv_data);
|
|
|
|
if (drv_data->tx != drv_data->tx_end)
|
|
tranf_success = 0;
|
|
} else if (drv_data->rx != NULL) {
|
|
/* read only half duplex */
|
|
|
|
drv_data->ops->read(drv_data);
|
|
if (drv_data->rx != drv_data->rx_end)
|
|
tranf_success = 0;
|
|
}
|
|
bfin_sport_spi_disable(drv_data);
|
|
|
|
if (!tranf_success) {
|
|
dev_dbg(drv_data->dev, "IO write error!\n");
|
|
drv_data->state = ERROR_STATE;
|
|
} else {
|
|
/* Update total byte transferred */
|
|
message->actual_length += transfer->len;
|
|
/* Move to next transfer of this msg */
|
|
drv_data->state = bfin_sport_spi_next_transfer(drv_data);
|
|
if (drv_data->cs_change)
|
|
bfin_sport_spi_cs_deactive(chip);
|
|
}
|
|
|
|
/* Schedule next transfer tasklet */
|
|
tasklet_schedule(&drv_data->pump_transfers);
|
|
}
|
|
|
|
/* pop a msg from queue and kick off real transfer */
|
|
static void
|
|
bfin_sport_spi_pump_messages(struct work_struct *work)
|
|
{
|
|
struct bfin_sport_spi_master_data *drv_data;
|
|
unsigned long flags;
|
|
struct spi_message *next_msg;
|
|
|
|
drv_data = container_of(work, struct bfin_sport_spi_master_data, pump_messages);
|
|
|
|
/* Lock queue and check for queue work */
|
|
spin_lock_irqsave(&drv_data->lock, flags);
|
|
if (list_empty(&drv_data->queue) || !drv_data->run) {
|
|
/* pumper kicked off but no work to do */
|
|
drv_data->busy = 0;
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
return;
|
|
}
|
|
|
|
/* Make sure we are not already running a message */
|
|
if (drv_data->cur_msg) {
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
return;
|
|
}
|
|
|
|
/* Extract head of queue */
|
|
next_msg = list_entry(drv_data->queue.next,
|
|
struct spi_message, queue);
|
|
|
|
drv_data->cur_msg = next_msg;
|
|
|
|
/* Setup the SSP using the per chip configuration */
|
|
drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
|
|
|
|
list_del_init(&drv_data->cur_msg->queue);
|
|
|
|
/* Initialize message state */
|
|
drv_data->cur_msg->state = START_STATE;
|
|
drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
|
|
struct spi_transfer, transfer_list);
|
|
bfin_sport_spi_restore_state(drv_data);
|
|
dev_dbg(drv_data->dev, "got a message to pump, "
|
|
"state is set to: baud %d, cs_gpio %i, ctl 0x%x\n",
|
|
drv_data->cur_chip->baud, drv_data->cur_chip->cs_gpio,
|
|
drv_data->cur_chip->ctl_reg);
|
|
|
|
dev_dbg(drv_data->dev,
|
|
"the first transfer len is %d\n",
|
|
drv_data->cur_transfer->len);
|
|
|
|
/* Mark as busy and launch transfers */
|
|
tasklet_schedule(&drv_data->pump_transfers);
|
|
|
|
drv_data->busy = 1;
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
}
|
|
|
|
/*
|
|
* got a msg to transfer, queue it in drv_data->queue.
|
|
* And kick off message pumper
|
|
*/
|
|
static int
|
|
bfin_sport_spi_transfer(struct spi_device *spi, struct spi_message *msg)
|
|
{
|
|
struct bfin_sport_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&drv_data->lock, flags);
|
|
|
|
if (!drv_data->run) {
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
return -ESHUTDOWN;
|
|
}
|
|
|
|
msg->actual_length = 0;
|
|
msg->status = -EINPROGRESS;
|
|
msg->state = START_STATE;
|
|
|
|
dev_dbg(&spi->dev, "adding an msg in transfer()\n");
|
|
list_add_tail(&msg->queue, &drv_data->queue);
|
|
|
|
if (drv_data->run && !drv_data->busy)
|
|
queue_work(drv_data->workqueue, &drv_data->pump_messages);
|
|
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Called every time common spi devices change state */
|
|
static int
|
|
bfin_sport_spi_setup(struct spi_device *spi)
|
|
{
|
|
struct bfin_sport_spi_slave_data *chip, *first = NULL;
|
|
int ret;
|
|
|
|
/* Only alloc (or use chip_info) on first setup */
|
|
chip = spi_get_ctldata(spi);
|
|
if (chip == NULL) {
|
|
struct bfin5xx_spi_chip *chip_info;
|
|
|
|
chip = first = kzalloc(sizeof(*chip), GFP_KERNEL);
|
|
if (!chip)
|
|
return -ENOMEM;
|
|
|
|
/* platform chip_info isn't required */
|
|
chip_info = spi->controller_data;
|
|
if (chip_info) {
|
|
/*
|
|
* DITFS and TDTYPE are only thing we don't set, but
|
|
* they probably shouldn't be changed by people.
|
|
*/
|
|
if (chip_info->ctl_reg || chip_info->enable_dma) {
|
|
ret = -EINVAL;
|
|
dev_err(&spi->dev, "don't set ctl_reg/enable_dma fields\n");
|
|
goto error;
|
|
}
|
|
chip->cs_chg_udelay = chip_info->cs_chg_udelay;
|
|
chip->idle_tx_val = chip_info->idle_tx_val;
|
|
}
|
|
}
|
|
|
|
/* translate common spi framework into our register
|
|
* following configure contents are same for tx and rx.
|
|
*/
|
|
|
|
if (spi->mode & SPI_CPHA)
|
|
chip->ctl_reg &= ~TCKFE;
|
|
else
|
|
chip->ctl_reg |= TCKFE;
|
|
|
|
if (spi->mode & SPI_LSB_FIRST)
|
|
chip->ctl_reg |= TLSBIT;
|
|
else
|
|
chip->ctl_reg &= ~TLSBIT;
|
|
|
|
/* Sport in master mode */
|
|
chip->ctl_reg |= ITCLK | ITFS | TFSR | LATFS | LTFS;
|
|
|
|
chip->baud = bfin_sport_hz_to_spi_baud(spi->max_speed_hz);
|
|
|
|
chip->cs_gpio = spi->chip_select;
|
|
ret = gpio_request(chip->cs_gpio, spi->modalias);
|
|
if (ret)
|
|
goto error;
|
|
|
|
dev_dbg(&spi->dev, "setup spi chip %s, width is %d\n",
|
|
spi->modalias, spi->bits_per_word);
|
|
dev_dbg(&spi->dev, "ctl_reg is 0x%x, GPIO is %i\n",
|
|
chip->ctl_reg, spi->chip_select);
|
|
|
|
spi_set_ctldata(spi, chip);
|
|
|
|
bfin_sport_spi_cs_deactive(chip);
|
|
|
|
return ret;
|
|
|
|
error:
|
|
kfree(first);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* callback for spi framework.
|
|
* clean driver specific data
|
|
*/
|
|
static void
|
|
bfin_sport_spi_cleanup(struct spi_device *spi)
|
|
{
|
|
struct bfin_sport_spi_slave_data *chip = spi_get_ctldata(spi);
|
|
|
|
if (!chip)
|
|
return;
|
|
|
|
gpio_free(chip->cs_gpio);
|
|
|
|
kfree(chip);
|
|
}
|
|
|
|
static int
|
|
bfin_sport_spi_init_queue(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
INIT_LIST_HEAD(&drv_data->queue);
|
|
spin_lock_init(&drv_data->lock);
|
|
|
|
drv_data->run = false;
|
|
drv_data->busy = 0;
|
|
|
|
/* init transfer tasklet */
|
|
tasklet_init(&drv_data->pump_transfers,
|
|
bfin_sport_spi_pump_transfers, (unsigned long)drv_data);
|
|
|
|
/* init messages workqueue */
|
|
INIT_WORK(&drv_data->pump_messages, bfin_sport_spi_pump_messages);
|
|
drv_data->workqueue =
|
|
create_singlethread_workqueue(dev_name(drv_data->master->dev.parent));
|
|
if (drv_data->workqueue == NULL)
|
|
return -EBUSY;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
bfin_sport_spi_start_queue(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&drv_data->lock, flags);
|
|
|
|
if (drv_data->run || drv_data->busy) {
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
return -EBUSY;
|
|
}
|
|
|
|
drv_data->run = true;
|
|
drv_data->cur_msg = NULL;
|
|
drv_data->cur_transfer = NULL;
|
|
drv_data->cur_chip = NULL;
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
|
|
queue_work(drv_data->workqueue, &drv_data->pump_messages);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int
|
|
bfin_sport_spi_stop_queue(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
unsigned long flags;
|
|
unsigned limit = 500;
|
|
int status = 0;
|
|
|
|
spin_lock_irqsave(&drv_data->lock, flags);
|
|
|
|
/*
|
|
* This is a bit lame, but is optimized for the common execution path.
|
|
* A wait_queue on the drv_data->busy could be used, but then the common
|
|
* execution path (pump_messages) would be required to call wake_up or
|
|
* friends on every SPI message. Do this instead
|
|
*/
|
|
drv_data->run = false;
|
|
while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) {
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
msleep(10);
|
|
spin_lock_irqsave(&drv_data->lock, flags);
|
|
}
|
|
|
|
if (!list_empty(&drv_data->queue) || drv_data->busy)
|
|
status = -EBUSY;
|
|
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
|
|
return status;
|
|
}
|
|
|
|
static inline int
|
|
bfin_sport_spi_destroy_queue(struct bfin_sport_spi_master_data *drv_data)
|
|
{
|
|
int status;
|
|
|
|
status = bfin_sport_spi_stop_queue(drv_data);
|
|
if (status)
|
|
return status;
|
|
|
|
destroy_workqueue(drv_data->workqueue);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bfin_sport_spi_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct bfin5xx_spi_master *platform_info;
|
|
struct spi_master *master;
|
|
struct resource *res, *ires;
|
|
struct bfin_sport_spi_master_data *drv_data;
|
|
int status;
|
|
|
|
platform_info = dev_get_platdata(dev);
|
|
|
|
/* Allocate master with space for drv_data */
|
|
master = spi_alloc_master(dev, sizeof(*master) + 16);
|
|
if (!master) {
|
|
dev_err(dev, "cannot alloc spi_master\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
drv_data = spi_master_get_devdata(master);
|
|
drv_data->master = master;
|
|
drv_data->dev = dev;
|
|
drv_data->pin_req = platform_info->pin_req;
|
|
|
|
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
|
|
master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
|
|
master->bus_num = pdev->id;
|
|
master->num_chipselect = platform_info->num_chipselect;
|
|
master->cleanup = bfin_sport_spi_cleanup;
|
|
master->setup = bfin_sport_spi_setup;
|
|
master->transfer = bfin_sport_spi_transfer;
|
|
|
|
/* Find and map our resources */
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (res == NULL) {
|
|
dev_err(dev, "cannot get IORESOURCE_MEM\n");
|
|
status = -ENOENT;
|
|
goto out_error_get_res;
|
|
}
|
|
|
|
drv_data->regs = ioremap(res->start, resource_size(res));
|
|
if (drv_data->regs == NULL) {
|
|
dev_err(dev, "cannot map registers\n");
|
|
status = -ENXIO;
|
|
goto out_error_ioremap;
|
|
}
|
|
|
|
ires = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
|
|
if (!ires) {
|
|
dev_err(dev, "cannot get IORESOURCE_IRQ\n");
|
|
status = -ENODEV;
|
|
goto out_error_get_ires;
|
|
}
|
|
drv_data->err_irq = ires->start;
|
|
|
|
/* Initial and start queue */
|
|
status = bfin_sport_spi_init_queue(drv_data);
|
|
if (status) {
|
|
dev_err(dev, "problem initializing queue\n");
|
|
goto out_error_queue_alloc;
|
|
}
|
|
|
|
status = bfin_sport_spi_start_queue(drv_data);
|
|
if (status) {
|
|
dev_err(dev, "problem starting queue\n");
|
|
goto out_error_queue_alloc;
|
|
}
|
|
|
|
status = request_irq(drv_data->err_irq, sport_err_handler,
|
|
0, "sport_spi_err", drv_data);
|
|
if (status) {
|
|
dev_err(dev, "unable to request sport err irq\n");
|
|
goto out_error_irq;
|
|
}
|
|
|
|
status = peripheral_request_list(drv_data->pin_req, DRV_NAME);
|
|
if (status) {
|
|
dev_err(dev, "requesting peripherals failed\n");
|
|
goto out_error_peripheral;
|
|
}
|
|
|
|
/* Register with the SPI framework */
|
|
platform_set_drvdata(pdev, drv_data);
|
|
status = spi_register_master(master);
|
|
if (status) {
|
|
dev_err(dev, "problem registering spi master\n");
|
|
goto out_error_master;
|
|
}
|
|
|
|
dev_info(dev, "%s, regs_base@%p\n", DRV_DESC, drv_data->regs);
|
|
return 0;
|
|
|
|
out_error_master:
|
|
peripheral_free_list(drv_data->pin_req);
|
|
out_error_peripheral:
|
|
free_irq(drv_data->err_irq, drv_data);
|
|
out_error_irq:
|
|
out_error_queue_alloc:
|
|
bfin_sport_spi_destroy_queue(drv_data);
|
|
out_error_get_ires:
|
|
iounmap(drv_data->regs);
|
|
out_error_ioremap:
|
|
out_error_get_res:
|
|
spi_master_put(master);
|
|
|
|
return status;
|
|
}
|
|
|
|
/* stop hardware and remove the driver */
|
|
static int bfin_sport_spi_remove(struct platform_device *pdev)
|
|
{
|
|
struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev);
|
|
int status = 0;
|
|
|
|
if (!drv_data)
|
|
return 0;
|
|
|
|
/* Remove the queue */
|
|
status = bfin_sport_spi_destroy_queue(drv_data);
|
|
if (status)
|
|
return status;
|
|
|
|
/* Disable the SSP at the peripheral and SOC level */
|
|
bfin_sport_spi_disable(drv_data);
|
|
|
|
/* Disconnect from the SPI framework */
|
|
spi_unregister_master(drv_data->master);
|
|
|
|
peripheral_free_list(drv_data->pin_req);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int bfin_sport_spi_suspend(struct device *dev)
|
|
{
|
|
struct bfin_sport_spi_master_data *drv_data = dev_get_drvdata(dev);
|
|
int status;
|
|
|
|
status = bfin_sport_spi_stop_queue(drv_data);
|
|
if (status)
|
|
return status;
|
|
|
|
/* stop hardware */
|
|
bfin_sport_spi_disable(drv_data);
|
|
|
|
return status;
|
|
}
|
|
|
|
static int bfin_sport_spi_resume(struct device *dev)
|
|
{
|
|
struct bfin_sport_spi_master_data *drv_data = dev_get_drvdata(dev);
|
|
int status;
|
|
|
|
/* Enable the SPI interface */
|
|
bfin_sport_spi_enable(drv_data);
|
|
|
|
/* Start the queue running */
|
|
status = bfin_sport_spi_start_queue(drv_data);
|
|
if (status)
|
|
dev_err(drv_data->dev, "problem resuming queue\n");
|
|
|
|
return status;
|
|
}
|
|
|
|
static SIMPLE_DEV_PM_OPS(bfin_sport_spi_pm_ops, bfin_sport_spi_suspend,
|
|
bfin_sport_spi_resume);
|
|
|
|
#define BFIN_SPORT_SPI_PM_OPS (&bfin_sport_spi_pm_ops)
|
|
#else
|
|
#define BFIN_SPORT_SPI_PM_OPS NULL
|
|
#endif
|
|
|
|
static struct platform_driver bfin_sport_spi_driver = {
|
|
.driver = {
|
|
.name = DRV_NAME,
|
|
.owner = THIS_MODULE,
|
|
.pm = BFIN_SPORT_SPI_PM_OPS,
|
|
},
|
|
.probe = bfin_sport_spi_probe,
|
|
.remove = bfin_sport_spi_remove,
|
|
};
|
|
module_platform_driver(bfin_sport_spi_driver);
|