1 /* 2 * leds-netxbig.c - Driver for the 2Big and 5Big Network series LEDs 3 * 4 * Copyright (C) 2010 LaCie 5 * 6 * Author: Simon Guinot <sguinot@lacie.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 23 #include <linux/module.h> 24 #include <linux/init.h> 25 #include <linux/irq.h> 26 #include <linux/slab.h> 27 #include <linux/spinlock.h> 28 #include <linux/platform_device.h> 29 #include <linux/gpio.h> 30 #include <linux/leds.h> 31 #include <linux/platform_data/leds-kirkwood-netxbig.h> 32 33 /* 34 * GPIO extension bus. 35 */ 36 37 static DEFINE_SPINLOCK(gpio_ext_lock); 38 39 static void gpio_ext_set_addr(struct netxbig_gpio_ext *gpio_ext, int addr) 40 { 41 int pin; 42 43 for (pin = 0; pin < gpio_ext->num_addr; pin++) 44 gpio_set_value(gpio_ext->addr[pin], (addr >> pin) & 1); 45 } 46 47 static void gpio_ext_set_data(struct netxbig_gpio_ext *gpio_ext, int data) 48 { 49 int pin; 50 51 for (pin = 0; pin < gpio_ext->num_data; pin++) 52 gpio_set_value(gpio_ext->data[pin], (data >> pin) & 1); 53 } 54 55 static void gpio_ext_enable_select(struct netxbig_gpio_ext *gpio_ext) 56 { 57 /* Enable select is done on the raising edge. */ 58 gpio_set_value(gpio_ext->enable, 0); 59 gpio_set_value(gpio_ext->enable, 1); 60 } 61 62 static void gpio_ext_set_value(struct netxbig_gpio_ext *gpio_ext, 63 int addr, int value) 64 { 65 unsigned long flags; 66 67 spin_lock_irqsave(&gpio_ext_lock, flags); 68 gpio_ext_set_addr(gpio_ext, addr); 69 gpio_ext_set_data(gpio_ext, value); 70 gpio_ext_enable_select(gpio_ext); 71 spin_unlock_irqrestore(&gpio_ext_lock, flags); 72 } 73 74 static int gpio_ext_init(struct netxbig_gpio_ext *gpio_ext) 75 { 76 int err; 77 int i; 78 79 if (unlikely(!gpio_ext)) 80 return -EINVAL; 81 82 /* Configure address GPIOs. */ 83 for (i = 0; i < gpio_ext->num_addr; i++) { 84 err = gpio_request_one(gpio_ext->addr[i], GPIOF_OUT_INIT_LOW, 85 "GPIO extension addr"); 86 if (err) 87 goto err_free_addr; 88 } 89 /* Configure data GPIOs. */ 90 for (i = 0; i < gpio_ext->num_data; i++) { 91 err = gpio_request_one(gpio_ext->data[i], GPIOF_OUT_INIT_LOW, 92 "GPIO extension data"); 93 if (err) 94 goto err_free_data; 95 } 96 /* Configure "enable select" GPIO. */ 97 err = gpio_request_one(gpio_ext->enable, GPIOF_OUT_INIT_LOW, 98 "GPIO extension enable"); 99 if (err) 100 goto err_free_data; 101 102 return 0; 103 104 err_free_data: 105 for (i = i - 1; i >= 0; i--) 106 gpio_free(gpio_ext->data[i]); 107 i = gpio_ext->num_addr; 108 err_free_addr: 109 for (i = i - 1; i >= 0; i--) 110 gpio_free(gpio_ext->addr[i]); 111 112 return err; 113 } 114 115 static void gpio_ext_free(struct netxbig_gpio_ext *gpio_ext) 116 { 117 int i; 118 119 gpio_free(gpio_ext->enable); 120 for (i = gpio_ext->num_addr - 1; i >= 0; i--) 121 gpio_free(gpio_ext->addr[i]); 122 for (i = gpio_ext->num_data - 1; i >= 0; i--) 123 gpio_free(gpio_ext->data[i]); 124 } 125 126 /* 127 * Class LED driver. 128 */ 129 130 struct netxbig_led_data { 131 struct netxbig_gpio_ext *gpio_ext; 132 struct led_classdev cdev; 133 int mode_addr; 134 int *mode_val; 135 int bright_addr; 136 int bright_max; 137 struct netxbig_led_timer *timer; 138 int num_timer; 139 enum netxbig_led_mode mode; 140 int sata; 141 spinlock_t lock; 142 }; 143 144 static int netxbig_led_get_timer_mode(enum netxbig_led_mode *mode, 145 unsigned long delay_on, 146 unsigned long delay_off, 147 struct netxbig_led_timer *timer, 148 int num_timer) 149 { 150 int i; 151 152 for (i = 0; i < num_timer; i++) { 153 if (timer[i].delay_on == delay_on && 154 timer[i].delay_off == delay_off) { 155 *mode = timer[i].mode; 156 return 0; 157 } 158 } 159 return -EINVAL; 160 } 161 162 static int netxbig_led_blink_set(struct led_classdev *led_cdev, 163 unsigned long *delay_on, 164 unsigned long *delay_off) 165 { 166 struct netxbig_led_data *led_dat = 167 container_of(led_cdev, struct netxbig_led_data, cdev); 168 enum netxbig_led_mode mode; 169 int mode_val; 170 int ret; 171 172 /* Look for a LED mode with the requested timer frequency. */ 173 ret = netxbig_led_get_timer_mode(&mode, *delay_on, *delay_off, 174 led_dat->timer, led_dat->num_timer); 175 if (ret < 0) 176 return ret; 177 178 mode_val = led_dat->mode_val[mode]; 179 if (mode_val == NETXBIG_LED_INVALID_MODE) 180 return -EINVAL; 181 182 spin_lock_irq(&led_dat->lock); 183 184 gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val); 185 led_dat->mode = mode; 186 187 spin_unlock_irq(&led_dat->lock); 188 189 return 0; 190 } 191 192 static void netxbig_led_set(struct led_classdev *led_cdev, 193 enum led_brightness value) 194 { 195 struct netxbig_led_data *led_dat = 196 container_of(led_cdev, struct netxbig_led_data, cdev); 197 enum netxbig_led_mode mode; 198 int mode_val, bright_val; 199 int set_brightness = 1; 200 unsigned long flags; 201 202 spin_lock_irqsave(&led_dat->lock, flags); 203 204 if (value == LED_OFF) { 205 mode = NETXBIG_LED_OFF; 206 set_brightness = 0; 207 } else { 208 if (led_dat->sata) 209 mode = NETXBIG_LED_SATA; 210 else if (led_dat->mode == NETXBIG_LED_OFF) 211 mode = NETXBIG_LED_ON; 212 else /* Keep 'timer' mode. */ 213 mode = led_dat->mode; 214 } 215 mode_val = led_dat->mode_val[mode]; 216 217 gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val); 218 led_dat->mode = mode; 219 /* 220 * Note that the brightness register is shared between all the 221 * SATA LEDs. So, change the brightness setting for a single 222 * SATA LED will affect all the others. 223 */ 224 if (set_brightness) { 225 bright_val = DIV_ROUND_UP(value * led_dat->bright_max, 226 LED_FULL); 227 gpio_ext_set_value(led_dat->gpio_ext, 228 led_dat->bright_addr, bright_val); 229 } 230 231 spin_unlock_irqrestore(&led_dat->lock, flags); 232 } 233 234 static ssize_t netxbig_led_sata_store(struct device *dev, 235 struct device_attribute *attr, 236 const char *buff, size_t count) 237 { 238 struct led_classdev *led_cdev = dev_get_drvdata(dev); 239 struct netxbig_led_data *led_dat = 240 container_of(led_cdev, struct netxbig_led_data, cdev); 241 unsigned long enable; 242 enum netxbig_led_mode mode; 243 int mode_val; 244 int ret; 245 246 ret = strict_strtoul(buff, 10, &enable); 247 if (ret < 0) 248 return ret; 249 250 enable = !!enable; 251 252 spin_lock_irq(&led_dat->lock); 253 254 if (led_dat->sata == enable) { 255 ret = count; 256 goto exit_unlock; 257 } 258 259 if (led_dat->mode != NETXBIG_LED_ON && 260 led_dat->mode != NETXBIG_LED_SATA) 261 mode = led_dat->mode; /* Keep modes 'off' and 'timer'. */ 262 else if (enable) 263 mode = NETXBIG_LED_SATA; 264 else 265 mode = NETXBIG_LED_ON; 266 267 mode_val = led_dat->mode_val[mode]; 268 if (mode_val == NETXBIG_LED_INVALID_MODE) { 269 ret = -EINVAL; 270 goto exit_unlock; 271 } 272 273 gpio_ext_set_value(led_dat->gpio_ext, led_dat->mode_addr, mode_val); 274 led_dat->mode = mode; 275 led_dat->sata = enable; 276 277 ret = count; 278 279 exit_unlock: 280 spin_unlock_irq(&led_dat->lock); 281 282 return ret; 283 } 284 285 static ssize_t netxbig_led_sata_show(struct device *dev, 286 struct device_attribute *attr, char *buf) 287 { 288 struct led_classdev *led_cdev = dev_get_drvdata(dev); 289 struct netxbig_led_data *led_dat = 290 container_of(led_cdev, struct netxbig_led_data, cdev); 291 292 return sprintf(buf, "%d\n", led_dat->sata); 293 } 294 295 static DEVICE_ATTR(sata, 0644, netxbig_led_sata_show, netxbig_led_sata_store); 296 297 static void delete_netxbig_led(struct netxbig_led_data *led_dat) 298 { 299 if (led_dat->mode_val[NETXBIG_LED_SATA] != NETXBIG_LED_INVALID_MODE) 300 device_remove_file(led_dat->cdev.dev, &dev_attr_sata); 301 led_classdev_unregister(&led_dat->cdev); 302 } 303 304 static int 305 create_netxbig_led(struct platform_device *pdev, 306 struct netxbig_led_data *led_dat, 307 const struct netxbig_led *template) 308 { 309 struct netxbig_led_platform_data *pdata = pdev->dev.platform_data; 310 int ret; 311 312 spin_lock_init(&led_dat->lock); 313 led_dat->gpio_ext = pdata->gpio_ext; 314 led_dat->cdev.name = template->name; 315 led_dat->cdev.default_trigger = template->default_trigger; 316 led_dat->cdev.blink_set = netxbig_led_blink_set; 317 led_dat->cdev.brightness_set = netxbig_led_set; 318 /* 319 * Because the GPIO extension bus don't allow to read registers 320 * value, there is no way to probe the LED initial state. 321 * So, the initial sysfs LED value for the "brightness" and "sata" 322 * attributes are inconsistent. 323 * 324 * Note that the initial LED state can't be reconfigured. 325 * The reason is that the LED behaviour must stay uniform during 326 * the whole boot process (bootloader+linux). 327 */ 328 led_dat->sata = 0; 329 led_dat->cdev.brightness = LED_OFF; 330 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; 331 led_dat->mode_addr = template->mode_addr; 332 led_dat->mode_val = template->mode_val; 333 led_dat->bright_addr = template->bright_addr; 334 led_dat->bright_max = (1 << pdata->gpio_ext->num_data) - 1; 335 led_dat->timer = pdata->timer; 336 led_dat->num_timer = pdata->num_timer; 337 338 ret = led_classdev_register(&pdev->dev, &led_dat->cdev); 339 if (ret < 0) 340 return ret; 341 342 /* 343 * If available, expose the SATA activity blink capability through 344 * a "sata" sysfs attribute. 345 */ 346 if (led_dat->mode_val[NETXBIG_LED_SATA] != NETXBIG_LED_INVALID_MODE) { 347 ret = device_create_file(led_dat->cdev.dev, &dev_attr_sata); 348 if (ret) 349 led_classdev_unregister(&led_dat->cdev); 350 } 351 352 return ret; 353 } 354 355 static int netxbig_led_probe(struct platform_device *pdev) 356 { 357 struct netxbig_led_platform_data *pdata = pdev->dev.platform_data; 358 struct netxbig_led_data *leds_data; 359 int i; 360 int ret; 361 362 if (!pdata) 363 return -EINVAL; 364 365 leds_data = devm_kzalloc(&pdev->dev, 366 sizeof(struct netxbig_led_data) * pdata->num_leds, GFP_KERNEL); 367 if (!leds_data) 368 return -ENOMEM; 369 370 ret = gpio_ext_init(pdata->gpio_ext); 371 if (ret < 0) 372 return ret; 373 374 for (i = 0; i < pdata->num_leds; i++) { 375 ret = create_netxbig_led(pdev, &leds_data[i], &pdata->leds[i]); 376 if (ret < 0) 377 goto err_free_leds; 378 } 379 380 platform_set_drvdata(pdev, leds_data); 381 382 return 0; 383 384 err_free_leds: 385 for (i = i - 1; i >= 0; i--) 386 delete_netxbig_led(&leds_data[i]); 387 388 gpio_ext_free(pdata->gpio_ext); 389 return ret; 390 } 391 392 static int __devexit netxbig_led_remove(struct platform_device *pdev) 393 { 394 struct netxbig_led_platform_data *pdata = pdev->dev.platform_data; 395 struct netxbig_led_data *leds_data; 396 int i; 397 398 leds_data = platform_get_drvdata(pdev); 399 400 for (i = 0; i < pdata->num_leds; i++) 401 delete_netxbig_led(&leds_data[i]); 402 403 gpio_ext_free(pdata->gpio_ext); 404 405 return 0; 406 } 407 408 static struct platform_driver netxbig_led_driver = { 409 .probe = netxbig_led_probe, 410 .remove = netxbig_led_remove, 411 .driver = { 412 .name = "leds-netxbig", 413 .owner = THIS_MODULE, 414 }, 415 }; 416 417 module_platform_driver(netxbig_led_driver); 418 419 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); 420 MODULE_DESCRIPTION("LED driver for LaCie xBig Network boards"); 421 MODULE_LICENSE("GPL"); 422 MODULE_ALIAS("platform:leds-netxbig"); 423