#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/delay.h>
#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/spi/spi.h>
#define SPI_SH_TBR 0x00
#define SPI_SH_RBR 0x00
#define SPI_SH_CR1 0x08
#define SPI_SH_CR2 0x10
#define SPI_SH_CR3 0x18
#define SPI_SH_CR4 0x20
#define SPI_SH_CR5 0x28
#define SPI_SH_TBE 0x80
#define SPI_SH_TBF 0x40
#define SPI_SH_RBE 0x20
#define SPI_SH_RBF 0x10
#define SPI_SH_PFONRD 0x08
#define SPI_SH_SSDB 0x04
#define SPI_SH_SSD 0x02
#define SPI_SH_SSA 0x01
#define SPI_SH_RSTF 0x80
#define SPI_SH_LOOPBK 0x40
#define SPI_SH_CPOL 0x20
#define SPI_SH_CPHA 0x10
#define SPI_SH_L1M0 0x08
#define SPI_SH_MAX_BYTE 0xFF
#define SPI_SH_TBEI 0x80
#define SPI_SH_TBFI 0x40
#define SPI_SH_RBEI 0x20
#define SPI_SH_RBFI 0x10
#define SPI_SH_WPABRT 0x04
#define SPI_SH_SSS 0x01
#define SPI_SH_P1L0 0x80
#define SPI_SH_PP1L0 0x40
#define SPI_SH_MUXI 0x20
#define SPI_SH_MUXIRQ 0x10
#define SPI_SH_FIFO_SIZE 32
#define SPI_SH_SEND_TIMEOUT (3 * HZ)
#define SPI_SH_RECEIVE_TIMEOUT (HZ >> 3)
#undef DEBUG
struct spi_sh_data {
void __iomem *addr;
int irq;
struct spi_controller *host;
unsigned long cr1;
wait_queue_head_t wait;
int width;
};
static void spi_sh_write(struct spi_sh_data *ss, unsigned long data,
unsigned long offset)
{
if (ss->width == 8)
iowrite8(data, ss->addr + (offset >> 2));
else if (ss->width == 32)
iowrite32(data, ss->addr + offset);
}
static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset)
{
if (ss->width == 8)
return ioread8(ss->addr + (offset >> 2));
else if (ss->width == 32)
return ioread32(ss->addr + offset);
else
return 0;
}
static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val,
unsigned long offset)
{
unsigned long tmp;
tmp = spi_sh_read(ss, offset);
tmp |= val;
spi_sh_write(ss, tmp, offset);
}
static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val,
unsigned long offset)
{
unsigned long tmp;
tmp = spi_sh_read(ss, offset);
tmp &= ~val;
spi_sh_write(ss, tmp, offset);
}
static void clear_fifo(struct spi_sh_data *ss)
{
spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
}
static int spi_sh_wait_receive_buffer(struct spi_sh_data *ss)
{
int timeout = 100000;
while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
udelay(10);
if (timeout-- < 0)
return -ETIMEDOUT;
}
return 0;
}
static int spi_sh_wait_write_buffer_empty(struct spi_sh_data *ss)
{
int timeout = 100000;
while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) {
udelay(10);
if (timeout-- < 0)
return -ETIMEDOUT;
}
return 0;
}
static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg,
struct spi_transfer *t)
{
int i, retval = 0;
int remain = t->len;
int cur_len;
unsigned char *data;
long ret;
if (t->len)
spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
data = (unsigned char *)t->tx_buf;
while (remain > 0) {
cur_len = min(SPI_SH_FIFO_SIZE, remain);
for (i = 0; i < cur_len &&
!(spi_sh_read(ss, SPI_SH_CR4) &
SPI_SH_WPABRT) &&
!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF);
i++)
spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR);
if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) {
spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4);
retval = -EIO;
break;
}
cur_len = i;
remain -= cur_len;
data += cur_len;
if (remain > 0) {
ss->cr1 &= ~SPI_SH_TBE;
spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
ret = wait_event_interruptible_timeout(ss->wait,
ss->cr1 & SPI_SH_TBE,
SPI_SH_SEND_TIMEOUT);
if (ret == 0 && !(ss->cr1 & SPI_SH_TBE)) {
printk(KERN_ERR "%s: timeout\n", __func__);
return -ETIMEDOUT;
}
}
}
if (list_is_last(&t->transfer_list, &mesg->transfers)) {
spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
ss->cr1 &= ~SPI_SH_TBE;
spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
ret = wait_event_interruptible_timeout(ss->wait,
ss->cr1 & SPI_SH_TBE,
SPI_SH_SEND_TIMEOUT);
if (ret == 0 && (ss->cr1 & SPI_SH_TBE)) {
printk(KERN_ERR "%s: timeout\n", __func__);
return -ETIMEDOUT;
}
}
return retval;
}
static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg,
struct spi_transfer *t)
{
int i;
int remain = t->len;
int cur_len;
unsigned char *data;
long ret;
if (t->len > SPI_SH_MAX_BYTE)
spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3);
else
spi_sh_write(ss, t->len, SPI_SH_CR3);
spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
spi_sh_wait_write_buffer_empty(ss);
data = (unsigned char *)t->rx_buf;
while (remain > 0) {
if (remain >= SPI_SH_FIFO_SIZE) {
ss->cr1 &= ~SPI_SH_RBF;
spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
ret = wait_event_interruptible_timeout(ss->wait,
ss->cr1 & SPI_SH_RBF,
SPI_SH_RECEIVE_TIMEOUT);
if (ret == 0 &&
spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
printk(KERN_ERR "%s: timeout\n", __func__);
return -ETIMEDOUT;
}
}
cur_len = min(SPI_SH_FIFO_SIZE, remain);
for (i = 0; i < cur_len; i++) {
if (spi_sh_wait_receive_buffer(ss))
break;
data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR);
}
remain -= cur_len;
data += cur_len;
}
if (t->len > SPI_SH_MAX_BYTE) {
clear_fifo(ss);
spi_sh_write(ss, 1, SPI_SH_CR3);
} else {
spi_sh_write(ss, 0, SPI_SH_CR3);
}
return 0;
}
static int spi_sh_transfer_one_message(struct spi_controller *ctlr,
struct spi_message *mesg)
{
struct spi_sh_data *ss = spi_controller_get_devdata(ctlr);
struct spi_transfer *t;
int ret;
pr_debug("%s: enter\n", __func__);
spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
list_for_each_entry(t, &mesg->transfers, transfer_list) {
pr_debug("tx_buf = %p, rx_buf = %p\n",
t->tx_buf, t->rx_buf);
pr_debug("len = %d, delay.value = %d\n",
t->len, t->delay.value);
if (t->tx_buf) {
ret = spi_sh_send(ss, mesg, t);
if (ret < 0)
goto error;
}
if (t->rx_buf) {
ret = spi_sh_receive(ss, mesg, t);
if (ret < 0)
goto error;
}
mesg->actual_length += t->len;
}
mesg->status = 0;
spi_finalize_current_message(ctlr);
clear_fifo(ss);
spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1);
udelay(100);
spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
SPI_SH_CR1);
clear_fifo(ss);
return 0;
error:
mesg->status = ret;
spi_finalize_current_message(ctlr);
if (mesg->complete)
mesg->complete(mesg->context);
spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
SPI_SH_CR1);
clear_fifo(ss);
return ret;
}
static int spi_sh_setup(struct spi_device *spi)
{
struct spi_sh_data *ss = spi_controller_get_devdata(spi->controller);
pr_debug("%s: enter\n", __func__);
spi_sh_write(ss, 0xfe, SPI_SH_CR1);
spi_sh_write(ss, 0x00, SPI_SH_CR1);
spi_sh_write(ss, 0x00, SPI_SH_CR3);
clear_fifo(ss);
spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2);
udelay(10);
return 0;
}
static void spi_sh_cleanup(struct spi_device *spi)
{
struct spi_sh_data *ss = spi_controller_get_devdata(spi->controller);
pr_debug("%s: enter\n", __func__);
spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
SPI_SH_CR1);
}
static irqreturn_t spi_sh_irq(int irq, void *_ss)
{
struct spi_sh_data *ss = (struct spi_sh_data *)_ss;
unsigned long cr1;
cr1 = spi_sh_read(ss, SPI_SH_CR1);
if (cr1 & SPI_SH_TBE)
ss->cr1 |= SPI_SH_TBE;
if (cr1 & SPI_SH_TBF)
ss->cr1 |= SPI_SH_TBF;
if (cr1 & SPI_SH_RBE)
ss->cr1 |= SPI_SH_RBE;
if (cr1 & SPI_SH_RBF)
ss->cr1 |= SPI_SH_RBF;
if (ss->cr1) {
spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4);
wake_up(&ss->wait);
}
return IRQ_HANDLED;
}
static void spi_sh_remove(struct platform_device *pdev)
{
struct spi_sh_data *ss = platform_get_drvdata(pdev);
spi_unregister_controller(ss->host);
free_irq(ss->irq, ss);
}
static int spi_sh_probe(struct platform_device *pdev)
{
struct resource *res;
struct spi_controller *host;
struct spi_sh_data *ss;
int ret, irq;
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)
return irq;
host = devm_spi_alloc_host(&pdev->dev, sizeof(struct spi_sh_data));
if (host == NULL) {
dev_err(&pdev->dev, "devm_spi_alloc_host error.\n");
return -ENOMEM;
}
ss = spi_controller_get_devdata(host);
platform_set_drvdata(pdev, ss);
switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
case IORESOURCE_MEM_8BIT:
ss->width = 8;
break;
case IORESOURCE_MEM_32BIT:
ss->width = 32;
break;
default:
dev_err(&pdev->dev, "No support width\n");
return -ENODEV;
}
ss->irq = irq;
ss->host = host;
ss->addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
if (ss->addr == NULL) {
dev_err(&pdev->dev, "ioremap error.\n");
return -ENOMEM;
}
init_waitqueue_head(&ss->wait);
ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss);
if (ret < 0) {
dev_err(&pdev->dev, "request_irq error\n");
return ret;
}
host->num_chipselect = 2;
host->bus_num = pdev->id;
host->setup = spi_sh_setup;
host->transfer_one_message = spi_sh_transfer_one_message;
host->cleanup = spi_sh_cleanup;
ret = spi_register_controller(host);
if (ret < 0) {
printk(KERN_ERR "spi_register_controller error.\n");
goto error3;
}
return 0;
error3:
free_irq(irq, ss);
return ret;
}
static struct platform_driver spi_sh_driver = {
.probe = spi_sh_probe,
.remove = spi_sh_remove,
.driver = {
.name = "sh_spi",
},
};
module_platform_driver(spi_sh_driver);
MODULE_DESCRIPTION("SH SPI bus driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Yoshihiro Shimoda");
MODULE_ALIAS("platform:sh_spi");
