SPI: tle620x power switch driver
Add support for the Infineon TLE62x0 series of low-side driver chips, such
as the TLE6220 or TLE6230. These can be viewed as output GPIOs specialized
for power switching applications. The driver provides a userspace
interface to those GPIOs, and to the switch status they provide.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 8ce16a0..a49270e 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -198,6 +198,15 @@
Note that this application programming interface is EXPERIMENTAL
and hence SUBJECT TO CHANGE WITHOUT NOTICE while it stabilizes.
+config SPI_TLE62X0
+ tristate "Infineon TLE62X0 (for power switching)"
+ depends on SPI_MASTER && SYSFS
+ help
+ SPI driver for Infineon TLE62X0 series line driver chips,
+ such as the TLE6220, TLE6230 and TLE6240. This provides a
+ sysfs interface, with each line presented as a kind of GPIO
+ exposing both switch control and diagnostic feedback.
+
#
# Add new SPI protocol masters in alphabetical order above this line
#
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 8929333..d9bd7f6 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -29,6 +29,7 @@
# SPI protocol drivers (device/link on bus)
obj-$(CONFIG_SPI_AT25) += at25.o
obj-$(CONFIG_SPI_SPIDEV) += spidev.o
+obj-$(CONFIG_SPI_TLE62X0) += tle62x0.o
# ... add above this line ...
# SPI slave controller drivers (upstream link)
diff --git a/drivers/spi/tle62x0.c b/drivers/spi/tle62x0.c
new file mode 100644
index 0000000..6da58ca
--- /dev/null
+++ b/drivers/spi/tle62x0.c
@@ -0,0 +1,328 @@
+/*
+ * tle62x0.c -- support Infineon TLE62x0 driver chips
+ *
+ * Copyright (c) 2007 Simtec Electronics
+ * Ben Dooks, <ben@simtec.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.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 %02x,%02x,%02x\n",
+ buff[0], buff[1], buff[2]);
+
+ 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);
+
+ 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 __devinit tle62x0_probe(struct spi_device *spi)
+{
+ struct tle62x0_state *st;
+ struct tle62x0_pdata *pdata;
+ int ptr;
+ int ret;
+
+ pdata = spi->dev.platform_data;
+ 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) {
+ dev_err(&spi->dev, "no memory for device state\n");
+ 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:
+ for (; ptr > 0; ptr--)
+ 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 __devexit 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]);
+
+ kfree(st);
+ return 0;
+}
+
+static struct spi_driver tle62x0_driver = {
+ .driver = {
+ .name = "tle62x0",
+ .owner = THIS_MODULE,
+ },
+ .probe = tle62x0_probe,
+ .remove = __devexit_p(tle62x0_remove),
+};
+
+static __init int tle62x0_init(void)
+{
+ return spi_register_driver(&tle62x0_driver);
+}
+
+static __exit void tle62x0_exit(void)
+{
+ spi_unregister_driver(&tle62x0_driver);
+}
+
+module_init(tle62x0_init);
+module_exit(tle62x0_exit);
+
+MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
+MODULE_DESCRIPTION("TLE62x0 SPI driver");
+MODULE_LICENSE("GPL v2");