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.h> 34 #include <linux/of_gpio.h> 35 36 /* 37 * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in 38 * relation with the SATA activity. This capability is exposed through the 39 * "sata" sysfs attribute. 40 * 41 * The following array detail the different LED registers and the combination 42 * of their possible values: 43 * 44 * cmd_led | slow_led | /SATA active | LED state 45 * | | | 46 * 1 | 0 | x | off 47 * - | 1 | x | on 48 * 0 | 0 | 1 | on 49 * 0 | 0 | 0 | blink (rate 300ms) 50 */ 51 52 enum ns2_led_modes { 53 NS_V2_LED_OFF, 54 NS_V2_LED_ON, 55 NS_V2_LED_SATA, 56 }; 57 58 struct ns2_led_mode_value { 59 enum ns2_led_modes mode; 60 int cmd_level; 61 int slow_level; 62 }; 63 64 static struct ns2_led_mode_value ns2_led_modval[] = { 65 { NS_V2_LED_OFF , 1, 0 }, 66 { NS_V2_LED_ON , 0, 1 }, 67 { NS_V2_LED_ON , 1, 1 }, 68 { NS_V2_LED_SATA, 0, 0 }, 69 }; 70 71 struct ns2_led_data { 72 struct led_classdev cdev; 73 unsigned cmd; 74 unsigned slow; 75 unsigned char sata; /* True when SATA mode active. */ 76 rwlock_t rw_lock; /* Lock GPIOs. */ 77 }; 78 79 static int ns2_led_get_mode(struct ns2_led_data *led_dat, 80 enum ns2_led_modes *mode) 81 { 82 int i; 83 int ret = -EINVAL; 84 int cmd_level; 85 int slow_level; 86 87 read_lock_irq(&led_dat->rw_lock); 88 89 cmd_level = gpio_get_value(led_dat->cmd); 90 slow_level = gpio_get_value(led_dat->slow); 91 92 for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) { 93 if (cmd_level == ns2_led_modval[i].cmd_level && 94 slow_level == ns2_led_modval[i].slow_level) { 95 *mode = ns2_led_modval[i].mode; 96 ret = 0; 97 break; 98 } 99 } 100 101 read_unlock_irq(&led_dat->rw_lock); 102 103 return ret; 104 } 105 106 static void ns2_led_set_mode(struct ns2_led_data *led_dat, 107 enum ns2_led_modes mode) 108 { 109 int i; 110 unsigned long flags; 111 112 write_lock_irqsave(&led_dat->rw_lock, flags); 113 114 for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) { 115 if (mode == ns2_led_modval[i].mode) { 116 gpio_set_value(led_dat->cmd, 117 ns2_led_modval[i].cmd_level); 118 gpio_set_value(led_dat->slow, 119 ns2_led_modval[i].slow_level); 120 } 121 } 122 123 write_unlock_irqrestore(&led_dat->rw_lock, flags); 124 } 125 126 static void ns2_led_set(struct led_classdev *led_cdev, 127 enum led_brightness value) 128 { 129 struct ns2_led_data *led_dat = 130 container_of(led_cdev, struct ns2_led_data, cdev); 131 enum ns2_led_modes mode; 132 133 if (value == LED_OFF) 134 mode = NS_V2_LED_OFF; 135 else if (led_dat->sata) 136 mode = NS_V2_LED_SATA; 137 else 138 mode = NS_V2_LED_ON; 139 140 ns2_led_set_mode(led_dat, mode); 141 } 142 143 static ssize_t ns2_led_sata_store(struct device *dev, 144 struct device_attribute *attr, 145 const char *buff, size_t count) 146 { 147 struct led_classdev *led_cdev = dev_get_drvdata(dev); 148 struct ns2_led_data *led_dat = 149 container_of(led_cdev, struct ns2_led_data, cdev); 150 int ret; 151 unsigned long enable; 152 enum ns2_led_modes mode; 153 154 ret = kstrtoul(buff, 10, &enable); 155 if (ret < 0) 156 return ret; 157 158 enable = !!enable; 159 160 if (led_dat->sata == enable) 161 return count; 162 163 ret = ns2_led_get_mode(led_dat, &mode); 164 if (ret < 0) 165 return ret; 166 167 if (enable && mode == NS_V2_LED_ON) 168 ns2_led_set_mode(led_dat, NS_V2_LED_SATA); 169 if (!enable && mode == NS_V2_LED_SATA) 170 ns2_led_set_mode(led_dat, NS_V2_LED_ON); 171 172 led_dat->sata = enable; 173 174 return count; 175 } 176 177 static ssize_t ns2_led_sata_show(struct device *dev, 178 struct device_attribute *attr, char *buf) 179 { 180 struct led_classdev *led_cdev = dev_get_drvdata(dev); 181 struct ns2_led_data *led_dat = 182 container_of(led_cdev, struct ns2_led_data, cdev); 183 184 return sprintf(buf, "%d\n", led_dat->sata); 185 } 186 187 static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store); 188 189 static int 190 create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat, 191 const struct ns2_led *template) 192 { 193 int ret; 194 enum ns2_led_modes mode; 195 196 ret = devm_gpio_request_one(&pdev->dev, template->cmd, 197 gpio_get_value(template->cmd) ? 198 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, 199 template->name); 200 if (ret) { 201 dev_err(&pdev->dev, "%s: failed to setup command GPIO\n", 202 template->name); 203 return ret; 204 } 205 206 ret = devm_gpio_request_one(&pdev->dev, template->slow, 207 gpio_get_value(template->slow) ? 208 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, 209 template->name); 210 if (ret) { 211 dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n", 212 template->name); 213 return ret; 214 } 215 216 rwlock_init(&led_dat->rw_lock); 217 218 led_dat->cdev.name = template->name; 219 led_dat->cdev.default_trigger = template->default_trigger; 220 led_dat->cdev.blink_set = NULL; 221 led_dat->cdev.brightness_set = ns2_led_set; 222 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; 223 led_dat->cmd = template->cmd; 224 led_dat->slow = template->slow; 225 226 ret = ns2_led_get_mode(led_dat, &mode); 227 if (ret < 0) 228 return ret; 229 230 /* Set LED initial state. */ 231 led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0; 232 led_dat->cdev.brightness = 233 (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL; 234 235 ret = led_classdev_register(&pdev->dev, &led_dat->cdev); 236 if (ret < 0) 237 return ret; 238 239 ret = device_create_file(led_dat->cdev.dev, &dev_attr_sata); 240 if (ret < 0) 241 goto err_free_cdev; 242 243 return 0; 244 245 err_free_cdev: 246 led_classdev_unregister(&led_dat->cdev); 247 return ret; 248 } 249 250 static void delete_ns2_led(struct ns2_led_data *led_dat) 251 { 252 device_remove_file(led_dat->cdev.dev, &dev_attr_sata); 253 led_classdev_unregister(&led_dat->cdev); 254 } 255 256 #ifdef CONFIG_OF_GPIO 257 /* 258 * Translate OpenFirmware node properties into platform_data. 259 */ 260 static int 261 ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata) 262 { 263 struct device_node *np = dev->of_node; 264 struct device_node *child; 265 struct ns2_led *leds; 266 int num_leds = 0; 267 int i = 0; 268 269 num_leds = of_get_child_count(np); 270 if (!num_leds) 271 return -ENODEV; 272 273 leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led), 274 GFP_KERNEL); 275 if (!leds) 276 return -ENOMEM; 277 278 for_each_child_of_node(np, child) { 279 const char *string; 280 int ret; 281 282 ret = of_get_named_gpio(child, "cmd-gpio", 0); 283 if (ret < 0) 284 return ret; 285 leds[i].cmd = ret; 286 ret = of_get_named_gpio(child, "slow-gpio", 0); 287 if (ret < 0) 288 return ret; 289 leds[i].slow = ret; 290 ret = of_property_read_string(child, "label", &string); 291 leds[i].name = (ret == 0) ? string : child->name; 292 ret = of_property_read_string(child, "linux,default-trigger", 293 &string); 294 if (ret == 0) 295 leds[i].default_trigger = string; 296 297 i++; 298 } 299 300 pdata->leds = leds; 301 pdata->num_leds = num_leds; 302 303 return 0; 304 } 305 306 static const struct of_device_id of_ns2_leds_match[] = { 307 { .compatible = "lacie,ns2-leds", }, 308 {}, 309 }; 310 #endif /* CONFIG_OF_GPIO */ 311 312 struct ns2_led_priv { 313 int num_leds; 314 struct ns2_led_data leds_data[]; 315 }; 316 317 static inline int sizeof_ns2_led_priv(int num_leds) 318 { 319 return sizeof(struct ns2_led_priv) + 320 (sizeof(struct ns2_led_data) * num_leds); 321 } 322 323 static int ns2_led_probe(struct platform_device *pdev) 324 { 325 struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev); 326 struct ns2_led_priv *priv; 327 int i; 328 int ret; 329 330 #ifdef CONFIG_OF_GPIO 331 if (!pdata) { 332 pdata = devm_kzalloc(&pdev->dev, 333 sizeof(struct ns2_led_platform_data), 334 GFP_KERNEL); 335 if (!pdata) 336 return -ENOMEM; 337 338 ret = ns2_leds_get_of_pdata(&pdev->dev, pdata); 339 if (ret) 340 return ret; 341 } 342 #else 343 if (!pdata) 344 return -EINVAL; 345 #endif /* CONFIG_OF_GPIO */ 346 347 priv = devm_kzalloc(&pdev->dev, 348 sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL); 349 if (!priv) 350 return -ENOMEM; 351 priv->num_leds = pdata->num_leds; 352 353 for (i = 0; i < priv->num_leds; i++) { 354 ret = create_ns2_led(pdev, &priv->leds_data[i], 355 &pdata->leds[i]); 356 if (ret < 0) { 357 for (i = i - 1; i >= 0; i--) 358 delete_ns2_led(&priv->leds_data[i]); 359 return ret; 360 } 361 } 362 363 platform_set_drvdata(pdev, priv); 364 365 return 0; 366 } 367 368 static int ns2_led_remove(struct platform_device *pdev) 369 { 370 int i; 371 struct ns2_led_priv *priv; 372 373 priv = platform_get_drvdata(pdev); 374 375 for (i = 0; i < priv->num_leds; i++) 376 delete_ns2_led(&priv->leds_data[i]); 377 378 return 0; 379 } 380 381 static struct platform_driver ns2_led_driver = { 382 .probe = ns2_led_probe, 383 .remove = ns2_led_remove, 384 .driver = { 385 .name = "leds-ns2", 386 .owner = THIS_MODULE, 387 .of_match_table = of_match_ptr(of_ns2_leds_match), 388 }, 389 }; 390 391 module_platform_driver(ns2_led_driver); 392 393 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); 394 MODULE_DESCRIPTION("Network Space v2 LED driver"); 395 MODULE_LICENSE("GPL"); 396 MODULE_ALIAS("platform:leds-ns2"); 397