1 /* 2 * leds-ns2.c - Driver for the Network Space v2 (and parents) dual-GPIO LED 3 * 4 * Copyright (C) 2010 LaCie 5 * 6 * Author: Simon Guinot <sguinot@lacie.com> 7 * 8 * Based on leds-gpio.c by Raphael Assenat <raph@8d.com> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 23 */ 24 25 #include <linux/kernel.h> 26 #include <linux/init.h> 27 #include <linux/platform_device.h> 28 #include <linux/slab.h> 29 #include <linux/gpio.h> 30 #include <linux/leds.h> 31 #include <linux/module.h> 32 #include <linux/platform_data/leds-kirkwood-ns2.h> 33 #include <linux/of_gpio.h> 34 35 /* 36 * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in 37 * relation with the SATA activity. This capability is exposed through the 38 * "sata" sysfs attribute. 39 * 40 * The following array detail the different LED registers and the combination 41 * of their possible values: 42 * 43 * cmd_led | slow_led | /SATA active | LED state 44 * | | | 45 * 1 | 0 | x | off 46 * - | 1 | x | on 47 * 0 | 0 | 1 | on 48 * 0 | 0 | 0 | blink (rate 300ms) 49 */ 50 51 enum ns2_led_modes { 52 NS_V2_LED_OFF, 53 NS_V2_LED_ON, 54 NS_V2_LED_SATA, 55 }; 56 57 struct ns2_led_mode_value { 58 enum ns2_led_modes mode; 59 int cmd_level; 60 int slow_level; 61 }; 62 63 static struct ns2_led_mode_value ns2_led_modval[] = { 64 { NS_V2_LED_OFF , 1, 0 }, 65 { NS_V2_LED_ON , 0, 1 }, 66 { NS_V2_LED_ON , 1, 1 }, 67 { NS_V2_LED_SATA, 0, 0 }, 68 }; 69 70 struct ns2_led_data { 71 struct led_classdev cdev; 72 unsigned cmd; 73 unsigned slow; 74 unsigned char sata; /* True when SATA mode active. */ 75 rwlock_t rw_lock; /* Lock GPIOs. */ 76 }; 77 78 static int ns2_led_get_mode(struct ns2_led_data *led_dat, 79 enum ns2_led_modes *mode) 80 { 81 int i; 82 int ret = -EINVAL; 83 int cmd_level; 84 int slow_level; 85 86 read_lock_irq(&led_dat->rw_lock); 87 88 cmd_level = gpio_get_value(led_dat->cmd); 89 slow_level = gpio_get_value(led_dat->slow); 90 91 for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) { 92 if (cmd_level == ns2_led_modval[i].cmd_level && 93 slow_level == ns2_led_modval[i].slow_level) { 94 *mode = ns2_led_modval[i].mode; 95 ret = 0; 96 break; 97 } 98 } 99 100 read_unlock_irq(&led_dat->rw_lock); 101 102 return ret; 103 } 104 105 static void ns2_led_set_mode(struct ns2_led_data *led_dat, 106 enum ns2_led_modes mode) 107 { 108 int i; 109 unsigned long flags; 110 111 write_lock_irqsave(&led_dat->rw_lock, flags); 112 113 for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) { 114 if (mode == ns2_led_modval[i].mode) { 115 gpio_set_value(led_dat->cmd, 116 ns2_led_modval[i].cmd_level); 117 gpio_set_value(led_dat->slow, 118 ns2_led_modval[i].slow_level); 119 } 120 } 121 122 write_unlock_irqrestore(&led_dat->rw_lock, flags); 123 } 124 125 static void ns2_led_set(struct led_classdev *led_cdev, 126 enum led_brightness value) 127 { 128 struct ns2_led_data *led_dat = 129 container_of(led_cdev, struct ns2_led_data, cdev); 130 enum ns2_led_modes mode; 131 132 if (value == LED_OFF) 133 mode = NS_V2_LED_OFF; 134 else if (led_dat->sata) 135 mode = NS_V2_LED_SATA; 136 else 137 mode = NS_V2_LED_ON; 138 139 ns2_led_set_mode(led_dat, mode); 140 } 141 142 static ssize_t ns2_led_sata_store(struct device *dev, 143 struct device_attribute *attr, 144 const char *buff, size_t count) 145 { 146 struct led_classdev *led_cdev = dev_get_drvdata(dev); 147 struct ns2_led_data *led_dat = 148 container_of(led_cdev, struct ns2_led_data, cdev); 149 int ret; 150 unsigned long enable; 151 enum ns2_led_modes mode; 152 153 ret = kstrtoul(buff, 10, &enable); 154 if (ret < 0) 155 return ret; 156 157 enable = !!enable; 158 159 if (led_dat->sata == enable) 160 return count; 161 162 ret = ns2_led_get_mode(led_dat, &mode); 163 if (ret < 0) 164 return ret; 165 166 if (enable && mode == NS_V2_LED_ON) 167 ns2_led_set_mode(led_dat, NS_V2_LED_SATA); 168 if (!enable && mode == NS_V2_LED_SATA) 169 ns2_led_set_mode(led_dat, NS_V2_LED_ON); 170 171 led_dat->sata = enable; 172 173 return count; 174 } 175 176 static ssize_t ns2_led_sata_show(struct device *dev, 177 struct device_attribute *attr, char *buf) 178 { 179 struct led_classdev *led_cdev = dev_get_drvdata(dev); 180 struct ns2_led_data *led_dat = 181 container_of(led_cdev, struct ns2_led_data, cdev); 182 183 return sprintf(buf, "%d\n", led_dat->sata); 184 } 185 186 static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store); 187 188 static int 189 create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat, 190 const struct ns2_led *template) 191 { 192 int ret; 193 enum ns2_led_modes mode; 194 195 ret = devm_gpio_request_one(&pdev->dev, template->cmd, 196 GPIOF_DIR_OUT | gpio_get_value(template->cmd), 197 template->name); 198 if (ret) { 199 dev_err(&pdev->dev, "%s: failed to setup command GPIO\n", 200 template->name); 201 return ret; 202 } 203 204 ret = devm_gpio_request_one(&pdev->dev, template->slow, 205 GPIOF_DIR_OUT | gpio_get_value(template->slow), 206 template->name); 207 if (ret) { 208 dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n", 209 template->name); 210 return ret; 211 } 212 213 rwlock_init(&led_dat->rw_lock); 214 215 led_dat->cdev.name = template->name; 216 led_dat->cdev.default_trigger = template->default_trigger; 217 led_dat->cdev.blink_set = NULL; 218 led_dat->cdev.brightness_set = ns2_led_set; 219 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; 220 led_dat->cmd = template->cmd; 221 led_dat->slow = template->slow; 222 223 ret = ns2_led_get_mode(led_dat, &mode); 224 if (ret < 0) 225 return ret; 226 227 /* Set LED initial state. */ 228 led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0; 229 led_dat->cdev.brightness = 230 (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL; 231 232 ret = led_classdev_register(&pdev->dev, &led_dat->cdev); 233 if (ret < 0) 234 return ret; 235 236 ret = device_create_file(led_dat->cdev.dev, &dev_attr_sata); 237 if (ret < 0) 238 goto err_free_cdev; 239 240 return 0; 241 242 err_free_cdev: 243 led_classdev_unregister(&led_dat->cdev); 244 return ret; 245 } 246 247 static void delete_ns2_led(struct ns2_led_data *led_dat) 248 { 249 device_remove_file(led_dat->cdev.dev, &dev_attr_sata); 250 led_classdev_unregister(&led_dat->cdev); 251 } 252 253 #ifdef CONFIG_OF_GPIO 254 /* 255 * Translate OpenFirmware node properties into platform_data. 256 */ 257 static int 258 ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata) 259 { 260 struct device_node *np = dev->of_node; 261 struct device_node *child; 262 struct ns2_led *leds; 263 int num_leds = 0; 264 int i = 0; 265 266 num_leds = of_get_child_count(np); 267 if (!num_leds) 268 return -ENODEV; 269 270 leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led), 271 GFP_KERNEL); 272 if (!leds) 273 return -ENOMEM; 274 275 for_each_child_of_node(np, child) { 276 const char *string; 277 int ret; 278 279 ret = of_get_named_gpio(child, "cmd-gpio", 0); 280 if (ret < 0) 281 return ret; 282 leds[i].cmd = ret; 283 ret = of_get_named_gpio(child, "slow-gpio", 0); 284 if (ret < 0) 285 return ret; 286 leds[i].slow = ret; 287 ret = of_property_read_string(child, "label", &string); 288 leds[i].name = (ret == 0) ? string : child->name; 289 ret = of_property_read_string(child, "linux,default-trigger", 290 &string); 291 if (ret == 0) 292 leds[i].default_trigger = string; 293 294 i++; 295 } 296 297 pdata->leds = leds; 298 pdata->num_leds = num_leds; 299 300 return 0; 301 } 302 303 static const struct of_device_id of_ns2_leds_match[] = { 304 { .compatible = "lacie,ns2-leds", }, 305 {}, 306 }; 307 #endif /* CONFIG_OF_GPIO */ 308 309 static int ns2_led_probe(struct platform_device *pdev) 310 { 311 struct ns2_led_platform_data *pdata = pdev->dev.platform_data; 312 struct ns2_led_data *leds_data; 313 int i; 314 int ret; 315 316 #ifdef CONFIG_OF_GPIO 317 if (!pdata) { 318 pdata = devm_kzalloc(&pdev->dev, 319 sizeof(struct ns2_led_platform_data), 320 GFP_KERNEL); 321 if (!pdata) 322 return -ENOMEM; 323 324 ret = ns2_leds_get_of_pdata(&pdev->dev, pdata); 325 if (ret) 326 return ret; 327 } 328 #else 329 if (!pdata) 330 return -EINVAL; 331 #endif /* CONFIG_OF_GPIO */ 332 333 leds_data = devm_kzalloc(&pdev->dev, sizeof(struct ns2_led_data) * 334 pdata->num_leds, GFP_KERNEL); 335 if (!leds_data) 336 return -ENOMEM; 337 338 for (i = 0; i < pdata->num_leds; i++) { 339 ret = create_ns2_led(pdev, &leds_data[i], &pdata->leds[i]); 340 if (ret < 0) { 341 for (i = i - 1; i >= 0; i--) 342 delete_ns2_led(&leds_data[i]); 343 return ret; 344 } 345 } 346 347 platform_set_drvdata(pdev, leds_data); 348 349 return 0; 350 } 351 352 static int ns2_led_remove(struct platform_device *pdev) 353 { 354 int i; 355 struct ns2_led_platform_data *pdata = pdev->dev.platform_data; 356 struct ns2_led_data *leds_data; 357 358 leds_data = platform_get_drvdata(pdev); 359 360 for (i = 0; i < pdata->num_leds; i++) 361 delete_ns2_led(&leds_data[i]); 362 363 platform_set_drvdata(pdev, NULL); 364 365 return 0; 366 } 367 368 static struct platform_driver ns2_led_driver = { 369 .probe = ns2_led_probe, 370 .remove = ns2_led_remove, 371 .driver = { 372 .name = "leds-ns2", 373 .owner = THIS_MODULE, 374 .of_match_table = of_match_ptr(of_ns2_leds_match), 375 }, 376 }; 377 378 module_platform_driver(ns2_led_driver); 379 380 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); 381 MODULE_DESCRIPTION("Network Space v2 LED driver"); 382 MODULE_LICENSE("GPL"); 383 MODULE_ALIAS("platform:leds-ns2"); 384