diff options
Diffstat (limited to 'drivers/spi/spi-tle62x0.c')
| -rw-r--r-- | drivers/spi/spi-tle62x0.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/drivers/spi/spi-tle62x0.c b/drivers/spi/spi-tle62x0.c new file mode 100644 index 000000000..60dc69a39 --- /dev/null +++ b/drivers/spi/spi-tle62x0.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Support Infineon TLE62x0 driver chips + * + * Copyright (c) 2007 Simtec Electronics + * Ben Dooks, <ben@simtec.co.uk> + */ + +#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 snprintf(buf, PAGE_SIZE, "%d", 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(sizeof(struct tle62x0_state), GFP_KERNEL); + 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; + } + } + + /* tle62x0_write(st); */ + 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 int 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); + return 0; +} + +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"); |