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alistair23-linux/drivers/spi/spi-rspi.c
Hiep Cao Minh cb52c673f8 spi/rspi: Fix 8bit data access, clear buffer 
The R8A7790 has QSPI module which added into RSPI together.
The transmit or receive data should be read from or written to
with the longword-, word-, or byte-access width. Modify word-
access to byte-access. In 16-bit data register, QSPI send or
receive datas access from high 8-bit while RSPI send or receive
datas access from low 8-bit on single mode.
Modify to reset transmit-receive buffer data and reading dummy
after data are transmited. RSPI has a TXMD bit on control
register(SPCR) to set transmit-only mode when transmit data or
Full-duplex synchronous mode when receive data. In QSPI the TXMD
bit is not supported, so after transmit data, dummy should be
read and before transmit or receive data the bufer register
should be reset.
This driver is the implementation of send and receive pio only,
DMA is not supported at this time.
Without this patch, it will occur error when transmit and receive

Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-10-10 11:23:25 +01:00

1041 lines
24 KiB
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/*
* 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
/*qspi only */
#define QSPI_SPBFCR 0x18
#define QSPI_SPBDCR 0x1a
#define QSPI_SPBMUL0 0x1c
#define QSPI_SPBMUL1 0x20
#define QSPI_SPBMUL2 0x24
#define QSPI_SPBMUL3 0x28
/* 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_8BIT 0x0000 /* qspi only */
#define SPCMD_SPB_16BIT 0x0100
#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
/* SPBFCR */
#define SPBFCR_TXRST 0x80 /* qspi only */
#define SPBFCR_RXRST 0x40 /* qspi only */
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;
const struct spi_ops *ops;
/* for dmaengine */
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 void rspi_write32(struct rspi_data *rspi, u32 data, u16 offset)
{
iowrite32(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);
}
/* optional functions */
struct spi_ops {
int (*set_config_register)(struct rspi_data *rspi, int access_size);
int (*send_pio)(struct rspi_data *rspi, struct spi_message *mesg,
struct spi_transfer *t);
int (*receive_pio)(struct rspi_data *rspi, struct spi_message *mesg,
struct spi_transfer *t);
};
/*
* functions for RSPI
*/
static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
{
int spbr;
/* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
rspi_write8(rspi, 0x00, RSPI_SPPCR);
/* Sets transfer bit rate */
spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
rspi_write8(rspi, clamp(spbr, 0, 255), 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;
}
/*
* functions for QSPI
*/
static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
{
u16 spcmd;
int spbr;
/* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
rspi_write8(rspi, 0x00, RSPI_SPPCR);
/* Sets transfer bit rate */
spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz);
rspi_write8(rspi, clamp(spbr, 0, 255), 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);
/* Data Length Setting */
if (access_size == 8)
spcmd = SPCMD_SPB_8BIT;
else if (access_size == 16)
spcmd = SPCMD_SPB_16BIT;
else if (access_size == 32)
spcmd = SPCMD_SPB_32BIT;
spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SSLKP | SPCMD_SPNDEN;
/* Resets transfer data length */
rspi_write32(rspi, 0, QSPI_SPBMUL0);
/* Resets transmit and receive buffer */
rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
/* Sets buffer to allow normal operation */
rspi_write8(rspi, 0x00, QSPI_SPBFCR);
/* Sets SPCMD */
rspi_write16(rspi, spcmd, RSPI_SPCMD0);
/* Enables SPI function in a master mode */
rspi_write8(rspi, SPCR_SPE | SPCR_MSTR, RSPI_SPCR);
return 0;
}
#define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
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_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 int qspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
struct spi_transfer *t)
{
int remain = t->len;
u8 *data;
rspi_write8(rspi, SPBFCR_TXRST, QSPI_SPBFCR);
rspi_write8(rspi, 0x00, QSPI_SPBFCR);
data = (u8 *)t->tx_buf;
while (remain > 0) {
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_write8(rspi, *data++, 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;
}
rspi_read8(rspi, RSPI_SPDR);
remain--;
}
/* Waiting for the last transmition */
rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
return 0;
}
#define send_pio(spi, mesg, t) spi->ops->send_pio(spi, mesg, t)
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 void qspi_receive_init(struct rspi_data *rspi)
{
unsigned char spsr;
spsr = rspi_read8(rspi, RSPI_SPSR);
if (spsr & SPSR_SPRF)
rspi_read8(rspi, RSPI_SPDR); /* dummy read */
rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
rspi_write8(rspi, 0x00, QSPI_SPBFCR);
}
static int qspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
struct spi_transfer *t)
{
int remain = t->len;
u8 *data;
qspi_receive_init(rspi);
data = (u8 *)t->rx_buf;
while (remain > 0) {
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_write8(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 8, 16 or 32-bit access */
*data++ = rspi_read8(rspi, RSPI_SPDR);
remain--;
}
return 0;
}
#define receive_pio(spi, mesg, t) spi->ops->receive_pio(spi, mesg, t)
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;
while (1) {
spin_lock_irqsave(&rspi->lock, flags);
if (list_empty(&rspi->queue)) {
spin_unlock_irqrestore(&rspi->lock, flags);
break;
}
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 = 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 = 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);
}
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;
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 int rspi_request_dma(struct rspi_data *rspi,
struct platform_device *pdev)
{
struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev);
struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
dma_cap_mask_t mask;
struct dma_slave_config cfg;
int ret;
if (!res || !rspi_pd)
return 0; /* The driver assumes no error. */
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->chan_rx = dma_request_channel(mask, shdma_chan_filter,
(void *)rspi_pd->dma_rx_id);
if (rspi->chan_rx) {
cfg.slave_id = rspi_pd->dma_rx_id;
cfg.direction = DMA_DEV_TO_MEM;
cfg.dst_addr = 0;
cfg.src_addr = res->start + RSPI_SPDR;
ret = dmaengine_slave_config(rspi->chan_rx, &cfg);
if (!ret)
dev_info(&pdev->dev, "Use DMA when rx.\n");
else
return ret;
}
}
if (rspi_pd->dma_tx_id) {
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
rspi->chan_tx = dma_request_channel(mask, shdma_chan_filter,
(void *)rspi_pd->dma_tx_id);
if (rspi->chan_tx) {
cfg.slave_id = rspi_pd->dma_tx_id;
cfg.direction = DMA_MEM_TO_DEV;
cfg.dst_addr = res->start + RSPI_SPDR;
cfg.src_addr = 0;
ret = dmaengine_slave_config(rspi->chan_tx, &cfg);
if (!ret)
dev_info(&pdev->dev, "Use DMA when tx\n");
else
return ret;
}
}
return 0;
}
static void 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 rspi_remove(struct platform_device *pdev)
{
struct rspi_data *rspi = spi_master_get(platform_get_drvdata(pdev));
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 rspi_probe(struct platform_device *pdev)
{
struct resource *res;
struct spi_master *master;
struct rspi_data *rspi;
int ret, irq;
char clk_name[16];
struct rspi_plat_data *rspi_pd = pdev->dev.platform_data;
const struct spi_ops *ops;
const struct platform_device_id *id_entry = pdev->id_entry;
ops = (struct spi_ops *)id_entry->driver_data;
/* ops parameter check */
if (!ops->set_config_register) {
dev_err(&pdev->dev, "there is no set_config_register\n");
return -ENODEV;
}
/* 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);
platform_set_drvdata(pdev, rspi);
rspi->ops = ops;
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), "%s%d", id_entry->name, 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 = rspi_pd->num_chipselect;
if (!master->num_chipselect)
master->num_chipselect = 2; /* default */
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;
ret = rspi_request_dma(rspi, pdev);
if (ret < 0) {
dev_err(&pdev->dev, "rspi_request_dma failed.\n");
goto error4;
}
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 spi_ops rspi_ops = {
.set_config_register = rspi_set_config_register,
.send_pio = rspi_send_pio,
.receive_pio = rspi_receive_pio,
};
static struct spi_ops qspi_ops = {
.set_config_register = qspi_set_config_register,
.send_pio = qspi_send_pio,
.receive_pio = qspi_receive_pio,
};
static struct platform_device_id spi_driver_ids[] = {
{ "rspi", (kernel_ulong_t)&rspi_ops },
{ "qspi", (kernel_ulong_t)&qspi_ops },
{},
};
MODULE_DEVICE_TABLE(platform, spi_driver_ids);
static struct platform_driver rspi_driver = {
.probe = rspi_probe,
.remove = rspi_remove,
.id_table = spi_driver_ids,
.driver = {
.name = "renesas_spi",
.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");
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