#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/spi/tle62x0.h>
#define CMD_READ 0x00
#define CMD_SET 0xff
#define DIAG_NORMAL 0x03
#define DIAG_OVERLOAD 0x02
#define DIAG_OPEN 0x01
#define DIAG_SHORTGND 0x00
struct tle62x0_state {
struct spi_device *us;
struct mutex lock;
unsigned int nr_gpio;
unsigned int gpio_state;
unsigned char tx_buff[4];
unsigned char rx_buff[4];
};
static int to_gpio_num(struct device_attribute *attr);
static inline int tle62x0_write(struct tle62x0_state *st)
{
unsigned char *buff = st->tx_buff;
unsigned int gpio_state = st->gpio_state;
buff[0] = CMD_SET;
if (st->nr_gpio == 16) {
buff[1] = gpio_state >> 8;
buff[2] = gpio_state;
} else {
buff[1] = gpio_state;
}
dev_dbg(&st->us->dev, "buff %3ph\n", buff);
return spi_write(st->us, buff, (st->nr_gpio == 16) ? 3 : 2);
}
static inline int tle62x0_read(struct tle62x0_state *st)
{
unsigned char *txbuff = st->tx_buff;
struct spi_transfer xfer = {
.tx_buf = txbuff,
.rx_buf = st->rx_buff,
.len = (st->nr_gpio * 2) / 8,
};
struct spi_message msg;
txbuff[0] = CMD_READ;
txbuff[1] = 0x00;
txbuff[2] = 0x00;
txbuff[3] = 0x00;
spi_message_init(&msg);
spi_message_add_tail(&xfer, &msg);
return spi_sync(st->us, &msg);
}
static unsigned char *decode_fault(unsigned int fault_code)
{
fault_code &= 3;
switch (fault_code) {
case DIAG_NORMAL:
return "N";
case DIAG_OVERLOAD:
return "V";
case DIAG_OPEN:
return "O";
case DIAG_SHORTGND:
return "G";
}
return "?";
}
static ssize_t tle62x0_status_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tle62x0_state *st = dev_get_drvdata(dev);
char *bp = buf;
unsigned char *buff = st->rx_buff;
unsigned long fault = 0;
int ptr;
int ret;
mutex_lock(&st->lock);
ret = tle62x0_read(st);
dev_dbg(dev, "tle62x0_read() returned %d\n", ret);
if (ret < 0) {
mutex_unlock(&st->lock);
return ret;
}
for (ptr = 0; ptr < (st->nr_gpio * 2)/8; ptr += 1) {
fault <<= 8;
fault |= ((unsigned long)buff[ptr]);
dev_dbg(dev, "byte %d is %02x\n", ptr, buff[ptr]);
}
for (ptr = 0; ptr < st->nr_gpio; ptr++) {
bp += sprintf(bp, "%s ", decode_fault(fault >> (ptr * 2)));
}
*bp++ = '\n';
mutex_unlock(&st->lock);
return bp - buf;
}
static DEVICE_ATTR(status_show, S_IRUGO, tle62x0_status_show, NULL);
static ssize_t tle62x0_gpio_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tle62x0_state *st = dev_get_drvdata(dev);
int gpio_num = to_gpio_num(attr);
int value;
mutex_lock(&st->lock);
value = (st->gpio_state >> gpio_num) & 1;
mutex_unlock(&st->lock);
return sysfs_emit(buf, "%d\n", value);
}
static ssize_t tle62x0_gpio_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct tle62x0_state *st = dev_get_drvdata(dev);
int gpio_num = to_gpio_num(attr);
unsigned long val;
char *endp;
val = simple_strtoul(buf, &endp, 0);
if (buf == endp)
return -EINVAL;
dev_dbg(dev, "setting gpio %d to %ld\n", gpio_num, val);
mutex_lock(&st->lock);
if (val)
st->gpio_state |= 1 << gpio_num;
else
st->gpio_state &= ~(1 << gpio_num);
tle62x0_write(st);
mutex_unlock(&st->lock);
return len;
}
static DEVICE_ATTR(gpio1, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio2, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio3, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio4, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio5, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio6, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio7, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio8, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio9, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio10, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio11, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio12, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio13, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio14, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio15, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static DEVICE_ATTR(gpio16, S_IWUSR|S_IRUGO,
tle62x0_gpio_show, tle62x0_gpio_store);
static struct device_attribute *gpio_attrs[] = {
[0] = &dev_attr_gpio1,
[1] = &dev_attr_gpio2,
[2] = &dev_attr_gpio3,
[3] = &dev_attr_gpio4,
[4] = &dev_attr_gpio5,
[5] = &dev_attr_gpio6,
[6] = &dev_attr_gpio7,
[7] = &dev_attr_gpio8,
[8] = &dev_attr_gpio9,
[9] = &dev_attr_gpio10,
[10] = &dev_attr_gpio11,
[11] = &dev_attr_gpio12,
[12] = &dev_attr_gpio13,
[13] = &dev_attr_gpio14,
[14] = &dev_attr_gpio15,
[15] = &dev_attr_gpio16
};
static int to_gpio_num(struct device_attribute *attr)
{
int ptr;
for (ptr = 0; ptr < ARRAY_SIZE(gpio_attrs); ptr++) {
if (gpio_attrs[ptr] == attr)
return ptr;
}
return -1;
}
static int tle62x0_probe(struct spi_device *spi)
{
struct tle62x0_state *st;
struct tle62x0_pdata *pdata;
int ptr;
int ret;
pdata = dev_get_platdata(&spi->dev);
if (pdata == NULL) {
dev_err(&spi->dev, "no device data specified\n");
return -EINVAL;
}
st = kzalloc_obj(struct tle62x0_state);
if (st == NULL)
return -ENOMEM;
st->us = spi;
st->nr_gpio = pdata->gpio_count;
st->gpio_state = pdata->init_state;
mutex_init(&st->lock);
ret = device_create_file(&spi->dev, &dev_attr_status_show);
if (ret) {
dev_err(&spi->dev, "cannot create status attribute\n");
goto err_status;
}
for (ptr = 0; ptr < pdata->gpio_count; ptr++) {
ret = device_create_file(&spi->dev, gpio_attrs[ptr]);
if (ret) {
dev_err(&spi->dev, "cannot create gpio attribute\n");
goto err_gpios;
}
}
spi_set_drvdata(spi, st);
return 0;
err_gpios:
while (--ptr >= 0)
device_remove_file(&spi->dev, gpio_attrs[ptr]);
device_remove_file(&spi->dev, &dev_attr_status_show);
err_status:
kfree(st);
return ret;
}
static void tle62x0_remove(struct spi_device *spi)
{
struct tle62x0_state *st = spi_get_drvdata(spi);
int ptr;
for (ptr = 0; ptr < st->nr_gpio; ptr++)
device_remove_file(&spi->dev, gpio_attrs[ptr]);
device_remove_file(&spi->dev, &dev_attr_status_show);
kfree(st);
}
static struct spi_driver tle62x0_driver = {
.driver = {
.name = "tle62x0",
},
.probe = tle62x0_probe,
.remove = tle62x0_remove,
};
module_spi_driver(tle62x0_driver);
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_DESCRIPTION("TLE62x0 SPI driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("spi:tle62x0");
