kernel-ark/drivers/spi/spi-rspi.c
Shimoda, Yoshihiro a3633fe7aa spi/rspi: add dmaengine support
This patch adds dmaengine supporting using sh_dma driver. The module
receives data by DMAC, it also needs TX DMAC to generate SPI's clocks.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-19 22:37:16 -06:00

830 lines
19 KiB
C

/*
* SH RSPI driver
*
* Copyright (C) 2012 Renesas Solutions Corp.
*
* Based on spi-sh.c:
* Copyright (C) 2011 Renesas Solutions Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/sh_dma.h>
#include <linux/spi/spi.h>
#include <linux/spi/rspi.h>
#define RSPI_SPCR 0x00
#define RSPI_SSLP 0x01
#define RSPI_SPPCR 0x02
#define RSPI_SPSR 0x03
#define RSPI_SPDR 0x04
#define RSPI_SPSCR 0x08
#define RSPI_SPSSR 0x09
#define RSPI_SPBR 0x0a
#define RSPI_SPDCR 0x0b
#define RSPI_SPCKD 0x0c
#define RSPI_SSLND 0x0d
#define RSPI_SPND 0x0e
#define RSPI_SPCR2 0x0f
#define RSPI_SPCMD0 0x10
#define RSPI_SPCMD1 0x12
#define RSPI_SPCMD2 0x14
#define RSPI_SPCMD3 0x16
#define RSPI_SPCMD4 0x18
#define RSPI_SPCMD5 0x1a
#define RSPI_SPCMD6 0x1c
#define RSPI_SPCMD7 0x1e
/* SPCR */
#define SPCR_SPRIE 0x80
#define SPCR_SPE 0x40
#define SPCR_SPTIE 0x20
#define SPCR_SPEIE 0x10
#define SPCR_MSTR 0x08
#define SPCR_MODFEN 0x04
#define SPCR_TXMD 0x02
#define SPCR_SPMS 0x01
/* SSLP */
#define SSLP_SSL1P 0x02
#define SSLP_SSL0P 0x01
/* SPPCR */
#define SPPCR_MOIFE 0x20
#define SPPCR_MOIFV 0x10
#define SPPCR_SPOM 0x04
#define SPPCR_SPLP2 0x02
#define SPPCR_SPLP 0x01
/* SPSR */
#define SPSR_SPRF 0x80
#define SPSR_SPTEF 0x20
#define SPSR_PERF 0x08
#define SPSR_MODF 0x04
#define SPSR_IDLNF 0x02
#define SPSR_OVRF 0x01
/* SPSCR */
#define SPSCR_SPSLN_MASK 0x07
/* SPSSR */
#define SPSSR_SPECM_MASK 0x70
#define SPSSR_SPCP_MASK 0x07
/* SPDCR */
#define SPDCR_SPLW 0x20
#define SPDCR_SPRDTD 0x10
#define SPDCR_SLSEL1 0x08
#define SPDCR_SLSEL0 0x04
#define SPDCR_SLSEL_MASK 0x0c
#define SPDCR_SPFC1 0x02
#define SPDCR_SPFC0 0x01
/* SPCKD */
#define SPCKD_SCKDL_MASK 0x07
/* SSLND */
#define SSLND_SLNDL_MASK 0x07
/* SPND */
#define SPND_SPNDL_MASK 0x07
/* SPCR2 */
#define SPCR2_PTE 0x08
#define SPCR2_SPIE 0x04
#define SPCR2_SPOE 0x02
#define SPCR2_SPPE 0x01
/* SPCMDn */
#define SPCMD_SCKDEN 0x8000
#define SPCMD_SLNDEN 0x4000
#define SPCMD_SPNDEN 0x2000
#define SPCMD_LSBF 0x1000
#define SPCMD_SPB_MASK 0x0f00
#define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK)
#define SPCMD_SPB_20BIT 0x0000
#define SPCMD_SPB_24BIT 0x0100
#define SPCMD_SPB_32BIT 0x0200
#define SPCMD_SSLKP 0x0080
#define SPCMD_SSLA_MASK 0x0030
#define SPCMD_BRDV_MASK 0x000c
#define SPCMD_CPOL 0x0002
#define SPCMD_CPHA 0x0001
struct rspi_data {
void __iomem *addr;
u32 max_speed_hz;
struct spi_master *master;
struct list_head queue;
struct work_struct ws;
wait_queue_head_t wait;
spinlock_t lock;
struct clk *clk;
unsigned char spsr;
/* for dmaengine */
struct sh_dmae_slave dma_tx;
struct sh_dmae_slave dma_rx;
struct dma_chan *chan_tx;
struct dma_chan *chan_rx;
int irq;
unsigned dma_width_16bit:1;
unsigned dma_callbacked:1;
};
static void rspi_write8(struct rspi_data *rspi, u8 data, u16 offset)
{
iowrite8(data, rspi->addr + offset);
}
static void rspi_write16(struct rspi_data *rspi, u16 data, u16 offset)
{
iowrite16(data, rspi->addr + offset);
}
static u8 rspi_read8(struct rspi_data *rspi, u16 offset)
{
return ioread8(rspi->addr + offset);
}
static u16 rspi_read16(struct rspi_data *rspi, u16 offset)
{
return ioread16(rspi->addr + offset);
}
static unsigned char rspi_calc_spbr(struct rspi_data *rspi)
{
int tmp;
unsigned char spbr;
tmp = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
spbr = clamp(tmp, 0, 255);
return spbr;
}
static void rspi_enable_irq(struct rspi_data *rspi, u8 enable)
{
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
}
static void rspi_disable_irq(struct rspi_data *rspi, u8 disable)
{
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
}
static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
u8 enable_bit)
{
int ret;
rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
rspi_enable_irq(rspi, enable_bit);
ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
if (ret == 0 && !(rspi->spsr & wait_mask))
return -ETIMEDOUT;
return 0;
}
static void rspi_assert_ssl(struct rspi_data *rspi)
{
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
}
static void rspi_negate_ssl(struct rspi_data *rspi)
{
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
}
static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
{
/* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
rspi_write8(rspi, 0x00, RSPI_SPPCR);
/* Sets transfer bit rate */
rspi_write8(rspi, rspi_calc_spbr(rspi), RSPI_SPBR);
/* Sets number of frames to be used: 1 frame */
rspi_write8(rspi, 0x00, RSPI_SPDCR);
/* Sets RSPCK, SSL, next-access delay value */
rspi_write8(rspi, 0x00, RSPI_SPCKD);
rspi_write8(rspi, 0x00, RSPI_SSLND);
rspi_write8(rspi, 0x00, RSPI_SPND);
/* Sets parity, interrupt mask */
rspi_write8(rspi, 0x00, RSPI_SPCR2);
/* Sets SPCMD */
rspi_write16(rspi, SPCMD_SPB_8_TO_16(access_size) | SPCMD_SSLKP,
RSPI_SPCMD0);
/* Sets RSPI mode */
rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
return 0;
}
static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
struct spi_transfer *t)
{
int remain = t->len;
u8 *data;
data = (u8 *)t->tx_buf;
while (remain > 0) {
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD,
RSPI_SPCR);
if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
dev_err(&rspi->master->dev,
"%s: tx empty timeout\n", __func__);
return -ETIMEDOUT;
}
rspi_write16(rspi, *data, RSPI_SPDR);
data++;
remain--;
}
/* Waiting for the last transmition */
rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
return 0;
}
static void rspi_dma_complete(void *arg)
{
struct rspi_data *rspi = arg;
rspi->dma_callbacked = 1;
wake_up_interruptible(&rspi->wait);
}
static int rspi_dma_map_sg(struct scatterlist *sg, void *buf, unsigned len,
struct dma_chan *chan,
enum dma_transfer_direction dir)
{
sg_init_table(sg, 1);
sg_set_buf(sg, buf, len);
sg_dma_len(sg) = len;
return dma_map_sg(chan->device->dev, sg, 1, dir);
}
static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan,
enum dma_transfer_direction dir)
{
dma_unmap_sg(chan->device->dev, sg, 1, dir);
}
static void rspi_memory_to_8bit(void *buf, const void *data, unsigned len)
{
u16 *dst = buf;
const u8 *src = data;
while (len) {
*dst++ = (u16)(*src++);
len--;
}
}
static void rspi_memory_from_8bit(void *buf, const void *data, unsigned len)
{
u8 *dst = buf;
const u16 *src = data;
while (len) {
*dst++ = (u8)*src++;
len--;
}
}
static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
{
struct scatterlist sg;
void *buf = NULL;
struct dma_async_tx_descriptor *desc;
unsigned len;
int ret = 0;
if (rspi->dma_width_16bit) {
/*
* If DMAC bus width is 16-bit, the driver allocates a dummy
* buffer. And, the driver converts original data into the
* DMAC data as the following format:
* original data: 1st byte, 2nd byte ...
* DMAC data: 1st byte, dummy, 2nd byte, dummy ...
*/
len = t->len * 2;
buf = kmalloc(len, GFP_KERNEL);
if (!buf)
return -ENOMEM;
rspi_memory_to_8bit(buf, t->tx_buf, t->len);
} else {
len = t->len;
buf = (void *)t->tx_buf;
}
if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE)) {
ret = -EFAULT;
goto end_nomap;
}
desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc) {
ret = -EIO;
goto end;
}
/*
* DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
* called. So, this driver disables the IRQ while DMA transfer.
*/
disable_irq(rspi->irq);
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, RSPI_SPCR);
rspi_enable_irq(rspi, SPCR_SPTIE);
rspi->dma_callbacked = 0;
desc->callback = rspi_dma_complete;
desc->callback_param = rspi;
dmaengine_submit(desc);
dma_async_issue_pending(rspi->chan_tx);
ret = wait_event_interruptible_timeout(rspi->wait,
rspi->dma_callbacked, HZ);
if (ret > 0 && rspi->dma_callbacked)
ret = 0;
else if (!ret)
ret = -ETIMEDOUT;
rspi_disable_irq(rspi, SPCR_SPTIE);
enable_irq(rspi->irq);
end:
rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE);
end_nomap:
if (rspi->dma_width_16bit)
kfree(buf);
return ret;
}
static void rspi_receive_init(struct rspi_data *rspi)
{
unsigned char spsr;
spsr = rspi_read8(rspi, RSPI_SPSR);
if (spsr & SPSR_SPRF)
rspi_read16(rspi, RSPI_SPDR); /* dummy read */
if (spsr & SPSR_OVRF)
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
RSPI_SPCR);
}
static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
struct spi_transfer *t)
{
int remain = t->len;
u8 *data;
rspi_receive_init(rspi);
data = (u8 *)t->rx_buf;
while (remain > 0) {
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD,
RSPI_SPCR);
if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
dev_err(&rspi->master->dev,
"%s: tx empty timeout\n", __func__);
return -ETIMEDOUT;
}
/* dummy write for generate clock */
rspi_write16(rspi, 0x00, RSPI_SPDR);
if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
dev_err(&rspi->master->dev,
"%s: receive timeout\n", __func__);
return -ETIMEDOUT;
}
/* SPDR allows 16 or 32-bit access only */
*data = (u8)rspi_read16(rspi, RSPI_SPDR);
data++;
remain--;
}
return 0;
}
static int rspi_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
{
struct scatterlist sg, sg_dummy;
void *dummy = NULL, *rx_buf = NULL;
struct dma_async_tx_descriptor *desc, *desc_dummy;
unsigned len;
int ret = 0;
if (rspi->dma_width_16bit) {
/*
* If DMAC bus width is 16-bit, the driver allocates a dummy
* buffer. And, finally the driver converts the DMAC data into
* actual data as the following format:
* DMAC data: 1st byte, dummy, 2nd byte, dummy ...
* actual data: 1st byte, 2nd byte ...
*/
len = t->len * 2;
rx_buf = kmalloc(len, GFP_KERNEL);
if (!rx_buf)
return -ENOMEM;
} else {
len = t->len;
rx_buf = t->rx_buf;
}
/* prepare dummy transfer to generate SPI clocks */
dummy = kzalloc(len, GFP_KERNEL);
if (!dummy) {
ret = -ENOMEM;
goto end_nomap;
}
if (!rspi_dma_map_sg(&sg_dummy, dummy, len, rspi->chan_tx,
DMA_TO_DEVICE)) {
ret = -EFAULT;
goto end_nomap;
}
desc_dummy = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_dummy, 1,
DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_dummy) {
ret = -EIO;
goto end_dummy_mapped;
}
/* prepare receive transfer */
if (!rspi_dma_map_sg(&sg, rx_buf, len, rspi->chan_rx,
DMA_FROM_DEVICE)) {
ret = -EFAULT;
goto end_dummy_mapped;
}
desc = dmaengine_prep_slave_sg(rspi->chan_rx, &sg, 1, DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc) {
ret = -EIO;
goto end;
}
rspi_receive_init(rspi);
/*
* DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
* called. So, this driver disables the IRQ while DMA transfer.
*/
disable_irq(rspi->irq);
rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, RSPI_SPCR);
rspi_enable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
rspi->dma_callbacked = 0;
desc->callback = rspi_dma_complete;
desc->callback_param = rspi;
dmaengine_submit(desc);
dma_async_issue_pending(rspi->chan_rx);
desc_dummy->callback = NULL; /* No callback */
dmaengine_submit(desc_dummy);
dma_async_issue_pending(rspi->chan_tx);
ret = wait_event_interruptible_timeout(rspi->wait,
rspi->dma_callbacked, HZ);
if (ret > 0 && rspi->dma_callbacked)
ret = 0;
else if (!ret)
ret = -ETIMEDOUT;
rspi_disable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
enable_irq(rspi->irq);
end:
rspi_dma_unmap_sg(&sg, rspi->chan_rx, DMA_FROM_DEVICE);
end_dummy_mapped:
rspi_dma_unmap_sg(&sg_dummy, rspi->chan_tx, DMA_TO_DEVICE);
end_nomap:
if (rspi->dma_width_16bit) {
if (!ret)
rspi_memory_from_8bit(t->rx_buf, rx_buf, t->len);
kfree(rx_buf);
}
kfree(dummy);
return ret;
}
static int rspi_is_dma(struct rspi_data *rspi, struct spi_transfer *t)
{
if (t->tx_buf && rspi->chan_tx)
return 1;
/* If the module receives data by DMAC, it also needs TX DMAC */
if (t->rx_buf && rspi->chan_tx && rspi->chan_rx)
return 1;
return 0;
}
static void rspi_work(struct work_struct *work)
{
struct rspi_data *rspi = container_of(work, struct rspi_data, ws);
struct spi_message *mesg;
struct spi_transfer *t;
unsigned long flags;
int ret;
spin_lock_irqsave(&rspi->lock, flags);
while (!list_empty(&rspi->queue)) {
mesg = list_entry(rspi->queue.next, struct spi_message, queue);
list_del_init(&mesg->queue);
spin_unlock_irqrestore(&rspi->lock, flags);
rspi_assert_ssl(rspi);
list_for_each_entry(t, &mesg->transfers, transfer_list) {
if (t->tx_buf) {
if (rspi_is_dma(rspi, t))
ret = rspi_send_dma(rspi, t);
else
ret = rspi_send_pio(rspi, mesg, t);
if (ret < 0)
goto error;
}
if (t->rx_buf) {
if (rspi_is_dma(rspi, t))
ret = rspi_receive_dma(rspi, t);
else
ret = rspi_receive_pio(rspi, mesg, t);
if (ret < 0)
goto error;
}
mesg->actual_length += t->len;
}
rspi_negate_ssl(rspi);
mesg->status = 0;
mesg->complete(mesg->context);
spin_lock_irqsave(&rspi->lock, flags);
}
return;
error:
mesg->status = ret;
mesg->complete(mesg->context);
}
static int rspi_setup(struct spi_device *spi)
{
struct rspi_data *rspi = spi_master_get_devdata(spi->master);
if (!spi->bits_per_word)
spi->bits_per_word = 8;
rspi->max_speed_hz = spi->max_speed_hz;
rspi_set_config_register(rspi, 8);
return 0;
}
static int rspi_transfer(struct spi_device *spi, struct spi_message *mesg)
{
struct rspi_data *rspi = spi_master_get_devdata(spi->master);
unsigned long flags;
mesg->actual_length = 0;
mesg->status = -EINPROGRESS;
spin_lock_irqsave(&rspi->lock, flags);
list_add_tail(&mesg->queue, &rspi->queue);
schedule_work(&rspi->ws);
spin_unlock_irqrestore(&rspi->lock, flags);
return 0;
}
static void rspi_cleanup(struct spi_device *spi)
{
}
static irqreturn_t rspi_irq(int irq, void *_sr)
{
struct rspi_data *rspi = (struct rspi_data *)_sr;
unsigned long spsr;
irqreturn_t ret = IRQ_NONE;
unsigned char disable_irq = 0;
rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
if (spsr & SPSR_SPRF)
disable_irq |= SPCR_SPRIE;
if (spsr & SPSR_SPTEF)
disable_irq |= SPCR_SPTIE;
if (disable_irq) {
ret = IRQ_HANDLED;
rspi_disable_irq(rspi, disable_irq);
wake_up(&rspi->wait);
}
return ret;
}
static bool rspi_filter(struct dma_chan *chan, void *filter_param)
{
chan->private = filter_param;
return true;
}
static void __devinit rspi_request_dma(struct rspi_data *rspi,
struct platform_device *pdev)
{
struct rspi_plat_data *rspi_pd = pdev->dev.platform_data;
dma_cap_mask_t mask;
if (!rspi_pd)
return;
rspi->dma_width_16bit = rspi_pd->dma_width_16bit;
/* If the module receives data by DMAC, it also needs TX DMAC */
if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) {
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
rspi->dma_rx.slave_id = rspi_pd->dma_rx_id;
rspi->chan_rx = dma_request_channel(mask, rspi_filter,
&rspi->dma_rx);
if (rspi->chan_rx)
dev_info(&pdev->dev, "Use DMA when rx.\n");
}
if (rspi_pd->dma_tx_id) {
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
rspi->dma_tx.slave_id = rspi_pd->dma_tx_id;
rspi->chan_tx = dma_request_channel(mask, rspi_filter,
&rspi->dma_tx);
if (rspi->chan_tx)
dev_info(&pdev->dev, "Use DMA when tx\n");
}
}
static void __devexit rspi_release_dma(struct rspi_data *rspi)
{
if (rspi->chan_tx)
dma_release_channel(rspi->chan_tx);
if (rspi->chan_rx)
dma_release_channel(rspi->chan_rx);
}
static int __devexit rspi_remove(struct platform_device *pdev)
{
struct rspi_data *rspi = dev_get_drvdata(&pdev->dev);
spi_unregister_master(rspi->master);
rspi_release_dma(rspi);
free_irq(platform_get_irq(pdev, 0), rspi);
clk_put(rspi->clk);
iounmap(rspi->addr);
spi_master_put(rspi->master);
return 0;
}
static int __devinit rspi_probe(struct platform_device *pdev)
{
struct resource *res;
struct spi_master *master;
struct rspi_data *rspi;
int ret, irq;
char clk_name[16];
/* get base addr */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (unlikely(res == NULL)) {
dev_err(&pdev->dev, "invalid resource\n");
return -EINVAL;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "platform_get_irq error\n");
return -ENODEV;
}
master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
if (master == NULL) {
dev_err(&pdev->dev, "spi_alloc_master error.\n");
return -ENOMEM;
}
rspi = spi_master_get_devdata(master);
dev_set_drvdata(&pdev->dev, rspi);
rspi->master = master;
rspi->addr = ioremap(res->start, resource_size(res));
if (rspi->addr == NULL) {
dev_err(&pdev->dev, "ioremap error.\n");
ret = -ENOMEM;
goto error1;
}
snprintf(clk_name, sizeof(clk_name), "rspi%d", pdev->id);
rspi->clk = clk_get(&pdev->dev, clk_name);
if (IS_ERR(rspi->clk)) {
dev_err(&pdev->dev, "cannot get clock\n");
ret = PTR_ERR(rspi->clk);
goto error2;
}
clk_enable(rspi->clk);
INIT_LIST_HEAD(&rspi->queue);
spin_lock_init(&rspi->lock);
INIT_WORK(&rspi->ws, rspi_work);
init_waitqueue_head(&rspi->wait);
master->num_chipselect = 2;
master->bus_num = pdev->id;
master->setup = rspi_setup;
master->transfer = rspi_transfer;
master->cleanup = rspi_cleanup;
ret = request_irq(irq, rspi_irq, 0, dev_name(&pdev->dev), rspi);
if (ret < 0) {
dev_err(&pdev->dev, "request_irq error\n");
goto error3;
}
rspi->irq = irq;
rspi_request_dma(rspi, pdev);
ret = spi_register_master(master);
if (ret < 0) {
dev_err(&pdev->dev, "spi_register_master error.\n");
goto error4;
}
dev_info(&pdev->dev, "probed\n");
return 0;
error4:
rspi_release_dma(rspi);
free_irq(irq, rspi);
error3:
clk_put(rspi->clk);
error2:
iounmap(rspi->addr);
error1:
spi_master_put(master);
return ret;
}
static struct platform_driver rspi_driver = {
.probe = rspi_probe,
.remove = __devexit_p(rspi_remove),
.driver = {
.name = "rspi",
.owner = THIS_MODULE,
},
};
module_platform_driver(rspi_driver);
MODULE_DESCRIPTION("Renesas RSPI bus driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Yoshihiro Shimoda");
MODULE_ALIAS("platform:rspi");