1/* 2 * tle62x0.c -- support Infineon TLE62x0 driver chips 3 * 4 * Copyright (c) 2007 Simtec Electronics 5 * Ben Dooks, <ben@simtec.co.uk> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 12#include <linux/device.h> 13#include <linux/kernel.h> 14#include <linux/slab.h> 15 16#include <linux/spi/spi.h> 17#include <linux/spi/tle62x0.h> 18 19 20#define CMD_READ 0x00 21#define CMD_SET 0xff 22 23#define DIAG_NORMAL 0x03 24#define DIAG_OVERLOAD 0x02 25#define DIAG_OPEN 0x01 26#define DIAG_SHORTGND 0x00 27 28struct tle62x0_state { 29 struct spi_device *us; 30 struct mutex lock; 31 unsigned int nr_gpio; 32 unsigned int gpio_state; 33 34 unsigned char tx_buff[4]; 35 unsigned char rx_buff[4]; 36}; 37 38static int to_gpio_num(struct device_attribute *attr); 39 40static inline int tle62x0_write(struct tle62x0_state *st) 41{ 42 unsigned char *buff = st->tx_buff; 43 unsigned int gpio_state = st->gpio_state; 44 45 buff[0] = CMD_SET; 46 47 if (st->nr_gpio == 16) { 48 buff[1] = gpio_state >> 8; 49 buff[2] = gpio_state; 50 } else { 51 buff[1] = gpio_state; 52 } 53 54 dev_dbg(&st->us->dev, "buff %02x,%02x,%02x\n", 55 buff[0], buff[1], buff[2]); 56 57 return spi_write(st->us, buff, (st->nr_gpio == 16) ? 3 : 2); 58} 59 60static inline int tle62x0_read(struct tle62x0_state *st) 61{ 62 unsigned char *txbuff = st->tx_buff; 63 struct spi_transfer xfer = { 64 .tx_buf = txbuff, 65 .rx_buf = st->rx_buff, 66 .len = (st->nr_gpio * 2) / 8, 67 }; 68 struct spi_message msg; 69 70 txbuff[0] = CMD_READ; 71 txbuff[1] = 0x00; 72 txbuff[2] = 0x00; 73 txbuff[3] = 0x00; 74 75 spi_message_init(&msg); 76 spi_message_add_tail(&xfer, &msg); 77 78 return spi_sync(st->us, &msg); 79} 80 81static unsigned char *decode_fault(unsigned int fault_code) 82{ 83 fault_code &= 3; 84 85 switch (fault_code) { 86 case DIAG_NORMAL: 87 return "N"; 88 case DIAG_OVERLOAD: 89 return "V"; 90 case DIAG_OPEN: 91 return "O"; 92 case DIAG_SHORTGND: 93 return "G"; 94 } 95 96 return "?"; 97} 98 99static ssize_t tle62x0_status_show(struct device *dev, 100 struct device_attribute *attr, char *buf) 101{ 102 struct tle62x0_state *st = dev_get_drvdata(dev); 103 char *bp = buf; 104 unsigned char *buff = st->rx_buff; 105 unsigned long fault = 0; 106 int ptr; 107 int ret; 108 109 mutex_lock(&st->lock); 110 ret = tle62x0_read(st); 111 dev_dbg(dev, "tle62x0_read() returned %d\n", ret); 112 if (ret < 0) { 113 mutex_unlock(&st->lock); 114 return ret; 115 } 116 117 for (ptr = 0; ptr < (st->nr_gpio * 2)/8; ptr += 1) { 118 fault <<= 8; 119 fault |= ((unsigned long)buff[ptr]); 120 121 dev_dbg(dev, "byte %d is %02x\n", ptr, buff[ptr]); 122 } 123 124 for (ptr = 0; ptr < st->nr_gpio; ptr++) { 125 bp += sprintf(bp, "%s ", decode_fault(fault >> (ptr * 2))); 126 } 127 128 *bp++ = '\n'; 129 130 mutex_unlock(&st->lock); 131 return bp - buf; 132} 133 134static DEVICE_ATTR(status_show, S_IRUGO, tle62x0_status_show, NULL); 135 136static ssize_t tle62x0_gpio_show(struct device *dev, 137 struct device_attribute *attr, char *buf) 138{ 139 struct tle62x0_state *st = dev_get_drvdata(dev); 140 int gpio_num = to_gpio_num(attr); 141 int value; 142 143 mutex_lock(&st->lock); 144 value = (st->gpio_state >> gpio_num) & 1; 145 mutex_unlock(&st->lock); 146 147 return snprintf(buf, PAGE_SIZE, "%d", value); 148} 149 150static ssize_t tle62x0_gpio_store(struct device *dev, 151 struct device_attribute *attr, 152 const char *buf, size_t len) 153{ 154 struct tle62x0_state *st = dev_get_drvdata(dev); 155 int gpio_num = to_gpio_num(attr); 156 unsigned long val; 157 char *endp; 158 159 val = simple_strtoul(buf, &endp, 0); 160 if (buf == endp) 161 return -EINVAL; 162 163 dev_dbg(dev, "setting gpio %d to %ld\n", gpio_num, val); 164 165 mutex_lock(&st->lock); 166 167 if (val) 168 st->gpio_state |= 1 << gpio_num; 169 else 170 st->gpio_state &= ~(1 << gpio_num); 171 172 tle62x0_write(st); 173 mutex_unlock(&st->lock); 174 175 return len; 176} 177 178static DEVICE_ATTR(gpio1, S_IWUSR|S_IRUGO, 179 tle62x0_gpio_show, tle62x0_gpio_store); 180static DEVICE_ATTR(gpio2, S_IWUSR|S_IRUGO, 181 tle62x0_gpio_show, tle62x0_gpio_store); 182static DEVICE_ATTR(gpio3, S_IWUSR|S_IRUGO, 183 tle62x0_gpio_show, tle62x0_gpio_store); 184static DEVICE_ATTR(gpio4, S_IWUSR|S_IRUGO, 185 tle62x0_gpio_show, tle62x0_gpio_store); 186static DEVICE_ATTR(gpio5, S_IWUSR|S_IRUGO, 187 tle62x0_gpio_show, tle62x0_gpio_store); 188static DEVICE_ATTR(gpio6, S_IWUSR|S_IRUGO, 189 tle62x0_gpio_show, tle62x0_gpio_store); 190static DEVICE_ATTR(gpio7, S_IWUSR|S_IRUGO, 191 tle62x0_gpio_show, tle62x0_gpio_store); 192static DEVICE_ATTR(gpio8, S_IWUSR|S_IRUGO, 193 tle62x0_gpio_show, tle62x0_gpio_store); 194static DEVICE_ATTR(gpio9, S_IWUSR|S_IRUGO, 195 tle62x0_gpio_show, tle62x0_gpio_store); 196static DEVICE_ATTR(gpio10, S_IWUSR|S_IRUGO, 197 tle62x0_gpio_show, tle62x0_gpio_store); 198static DEVICE_ATTR(gpio11, S_IWUSR|S_IRUGO, 199 tle62x0_gpio_show, tle62x0_gpio_store); 200static DEVICE_ATTR(gpio12, S_IWUSR|S_IRUGO, 201 tle62x0_gpio_show, tle62x0_gpio_store); 202static DEVICE_ATTR(gpio13, S_IWUSR|S_IRUGO, 203 tle62x0_gpio_show, tle62x0_gpio_store); 204static DEVICE_ATTR(gpio14, S_IWUSR|S_IRUGO, 205 tle62x0_gpio_show, tle62x0_gpio_store); 206static DEVICE_ATTR(gpio15, S_IWUSR|S_IRUGO, 207 tle62x0_gpio_show, tle62x0_gpio_store); 208static DEVICE_ATTR(gpio16, S_IWUSR|S_IRUGO, 209 tle62x0_gpio_show, tle62x0_gpio_store); 210 211static struct device_attribute *gpio_attrs[] = { 212 [0] = &dev_attr_gpio1, 213 [1] = &dev_attr_gpio2, 214 [2] = &dev_attr_gpio3, 215 [3] = &dev_attr_gpio4, 216 [4] = &dev_attr_gpio5, 217 [5] = &dev_attr_gpio6, 218 [6] = &dev_attr_gpio7, 219 [7] = &dev_attr_gpio8, 220 [8] = &dev_attr_gpio9, 221 [9] = &dev_attr_gpio10, 222 [10] = &dev_attr_gpio11, 223 [11] = &dev_attr_gpio12, 224 [12] = &dev_attr_gpio13, 225 [13] = &dev_attr_gpio14, 226 [14] = &dev_attr_gpio15, 227 [15] = &dev_attr_gpio16 228}; 229 230static int to_gpio_num(struct device_attribute *attr) 231{ 232 int ptr; 233 234 for (ptr = 0; ptr < ARRAY_SIZE(gpio_attrs); ptr++) { 235 if (gpio_attrs[ptr] == attr) 236 return ptr; 237 } 238 239 return -1; 240} 241 242static int __devinit tle62x0_probe(struct spi_device *spi) 243{ 244 struct tle62x0_state *st; 245 struct tle62x0_pdata *pdata; 246 int ptr; 247 int ret; 248 249 pdata = spi->dev.platform_data; 250 if (pdata == NULL) { 251 dev_err(&spi->dev, "no device data specified\n"); 252 return -EINVAL; 253 } 254 255 st = kzalloc(sizeof(struct tle62x0_state), GFP_KERNEL); 256 if (st == NULL) { 257 dev_err(&spi->dev, "no memory for device state\n"); 258 return -ENOMEM; 259 } 260 261 st->us = spi; 262 st->nr_gpio = pdata->gpio_count; 263 st->gpio_state = pdata->init_state; 264 265 mutex_init(&st->lock); 266 267 ret = device_create_file(&spi->dev, &dev_attr_status_show); 268 if (ret) { 269 dev_err(&spi->dev, "cannot create status attribute\n"); 270 goto err_status; 271 } 272 273 for (ptr = 0; ptr < pdata->gpio_count; ptr++) { 274 ret = device_create_file(&spi->dev, gpio_attrs[ptr]); 275 if (ret) { 276 dev_err(&spi->dev, "cannot create gpio attribute\n"); 277 goto err_gpios; 278 } 279 } 280 281 /* tle62x0_write(st); */ 282 spi_set_drvdata(spi, st); 283 return 0; 284 285 err_gpios: 286 for (; ptr > 0; ptr--) 287 device_remove_file(&spi->dev, gpio_attrs[ptr]); 288 289 device_remove_file(&spi->dev, &dev_attr_status_show); 290 291 err_status: 292 kfree(st); 293 return ret; 294} 295 296static int __devexit tle62x0_remove(struct spi_device *spi) 297{ 298 struct tle62x0_state *st = spi_get_drvdata(spi); 299 int ptr; 300 301 for (ptr = 0; ptr < st->nr_gpio; ptr++) 302 device_remove_file(&spi->dev, gpio_attrs[ptr]); 303 304 kfree(st); 305 return 0; 306} 307 308static struct spi_driver tle62x0_driver = { 309 .driver = { 310 .name = "tle62x0", 311 .owner = THIS_MODULE, 312 }, 313 .probe = tle62x0_probe, 314 .remove = __devexit_p(tle62x0_remove), 315}; 316 317static __init int tle62x0_init(void) 318{ 319 return spi_register_driver(&tle62x0_driver); 320} 321 322static __exit void tle62x0_exit(void) 323{ 324 spi_unregister_driver(&tle62x0_driver); 325} 326 327module_init(tle62x0_init); 328module_exit(tle62x0_exit); 329 330MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); 331MODULE_DESCRIPTION("TLE62x0 SPI driver"); 332MODULE_LICENSE("GPL v2"); 333MODULE_ALIAS("spi:tle62x0"); 334