/* * 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");