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 gpio_get_value(template->cmd) ? 197 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, 198 template->name); 199 if (ret) { 200 dev_err(&pdev->dev, "%s: failed to setup command GPIO\n", 201 template->name); 202 return ret; 203 } 204 205 ret = devm_gpio_request_one(&pdev->dev, template->slow, 206 gpio_get_value(template->slow) ? 207 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, 208 template->name); 209 if (ret) { 210 dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n", 211 template->name); 212 return ret; 213 } 214 215 rwlock_init(&led_dat->rw_lock); 216 217 led_dat->cdev.name = template->name; 218 led_dat->cdev.default_trigger = template->default_trigger; 219 led_dat->cdev.blink_set = NULL; 220 led_dat->cdev.brightness_set = ns2_led_set; 221 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; 222 led_dat->cmd = template->cmd; 223 led_dat->slow = template->slow; 224 225 ret = ns2_led_get_mode(led_dat, &mode); 226 if (ret < 0) 227 return ret; 228 229 /* Set LED initial state. */ 230 led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0; 231 led_dat->cdev.brightness = 232 (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL; 233 234 ret = led_classdev_register(&pdev->dev, &led_dat->cdev); 235 if (ret < 0) 236 return ret; 237 238 ret = device_create_file(led_dat->cdev.dev, &dev_attr_sata); 239 if (ret < 0) 240 goto err_free_cdev; 241 242 return 0; 243 244 err_free_cdev: 245 led_classdev_unregister(&led_dat->cdev); 246 return ret; 247 } 248 249 static void delete_ns2_led(struct ns2_led_data *led_dat) 250 { 251 device_remove_file(led_dat->cdev.dev, &dev_attr_sata); 252 led_classdev_unregister(&led_dat->cdev); 253 } 254 255 #ifdef CONFIG_OF_GPIO 256 /* 257 * Translate OpenFirmware node properties into platform_data. 258 */ 259 static int 260 ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata) 261 { 262 struct device_node *np = dev->of_node; 263 struct device_node *child; 264 struct ns2_led *leds; 265 int num_leds = 0; 266 int i = 0; 267 268 num_leds = of_get_child_count(np); 269 if (!num_leds) 270 return -ENODEV; 271 272 leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led), 273 GFP_KERNEL); 274 if (!leds) 275 return -ENOMEM; 276 277 for_each_child_of_node(np, child) { 278 const char *string; 279 int ret; 280 281 ret = of_get_named_gpio(child, "cmd-gpio", 0); 282 if (ret < 0) 283 return ret; 284 leds[i].cmd = ret; 285 ret = of_get_named_gpio(child, "slow-gpio", 0); 286 if (ret < 0) 287 return ret; 288 leds[i].slow = ret; 289 ret = of_property_read_string(child, "label", &string); 290 leds[i].name = (ret == 0) ? string : child->name; 291 ret = of_property_read_string(child, "linux,default-trigger", 292 &string); 293 if (ret == 0) 294 leds[i].default_trigger = string; 295 296 i++; 297 } 298 299 pdata->leds = leds; 300 pdata->num_leds = num_leds; 301 302 return 0; 303 } 304 305 static const struct of_device_id of_ns2_leds_match[] = { 306 { .compatible = "lacie,ns2-leds", }, 307 {}, 308 }; 309 #endif /* CONFIG_OF_GPIO */ 310 311 struct ns2_led_priv { 312 int num_leds; 313 struct ns2_led_data leds_data[]; 314 }; 315 316 static inline int sizeof_ns2_led_priv(int num_leds) 317 { 318 return sizeof(struct ns2_led_priv) + 319 (sizeof(struct ns2_led_data) * num_leds); 320 } 321 322 static int ns2_led_probe(struct platform_device *pdev) 323 { 324 struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev); 325 struct ns2_led_priv *priv; 326 int i; 327 int ret; 328 329 #ifdef CONFIG_OF_GPIO 330 if (!pdata) { 331 pdata = devm_kzalloc(&pdev->dev, 332 sizeof(struct ns2_led_platform_data), 333 GFP_KERNEL); 334 if (!pdata) 335 return -ENOMEM; 336 337 ret = ns2_leds_get_of_pdata(&pdev->dev, pdata); 338 if (ret) 339 return ret; 340 } 341 #else 342 if (!pdata) 343 return -EINVAL; 344 #endif /* CONFIG_OF_GPIO */ 345 346 priv = devm_kzalloc(&pdev->dev, 347 sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL); 348 if (!priv) 349 return -ENOMEM; 350 priv->num_leds = pdata->num_leds; 351 352 for (i = 0; i < priv->num_leds; i++) { 353 ret = create_ns2_led(pdev, &priv->leds_data[i], 354 &pdata->leds[i]); 355 if (ret < 0) { 356 for (i = i - 1; i >= 0; i--) 357 delete_ns2_led(&priv->leds_data[i]); 358 return ret; 359 } 360 } 361 362 platform_set_drvdata(pdev, priv); 363 364 return 0; 365 } 366 367 static int ns2_led_remove(struct platform_device *pdev) 368 { 369 int i; 370 struct ns2_led_priv *priv; 371 372 priv = platform_get_drvdata(pdev); 373 374 for (i = 0; i < priv->num_leds; i++) 375 delete_ns2_led(&priv->leds_data[i]); 376 377 return 0; 378 } 379 380 static struct platform_driver ns2_led_driver = { 381 .probe = ns2_led_probe, 382 .remove = ns2_led_remove, 383 .driver = { 384 .name = "leds-ns2", 385 .owner = THIS_MODULE, 386 .of_match_table = of_match_ptr(of_ns2_leds_match), 387 }, 388 }; 389 390 module_platform_driver(ns2_led_driver); 391 392 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); 393 MODULE_DESCRIPTION("Network Space v2 LED driver"); 394 MODULE_LICENSE("GPL"); 395 MODULE_ALIAS("platform:leds-ns2"); 396