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/platform_device.h> 27 #include <linux/slab.h> 28 #include <linux/gpio.h> 29 #include <linux/leds.h> 30 #include <linux/module.h> 31 #include <linux/platform_data/leds-kirkwood-ns2.h> 32 #include <linux/of.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 struct attribute *ns2_led_attrs[] = { 189 &dev_attr_sata.attr, 190 NULL 191 }; 192 ATTRIBUTE_GROUPS(ns2_led); 193 194 static int 195 create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat, 196 const struct ns2_led *template) 197 { 198 int ret; 199 enum ns2_led_modes mode; 200 201 ret = devm_gpio_request_one(&pdev->dev, template->cmd, 202 gpio_get_value(template->cmd) ? 203 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, 204 template->name); 205 if (ret) { 206 dev_err(&pdev->dev, "%s: failed to setup command GPIO\n", 207 template->name); 208 return ret; 209 } 210 211 ret = devm_gpio_request_one(&pdev->dev, template->slow, 212 gpio_get_value(template->slow) ? 213 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW, 214 template->name); 215 if (ret) { 216 dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n", 217 template->name); 218 return ret; 219 } 220 221 rwlock_init(&led_dat->rw_lock); 222 223 led_dat->cdev.name = template->name; 224 led_dat->cdev.default_trigger = template->default_trigger; 225 led_dat->cdev.blink_set = NULL; 226 led_dat->cdev.brightness_set = ns2_led_set; 227 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; 228 led_dat->cdev.groups = ns2_led_groups; 229 led_dat->cmd = template->cmd; 230 led_dat->slow = template->slow; 231 232 ret = ns2_led_get_mode(led_dat, &mode); 233 if (ret < 0) 234 return ret; 235 236 /* Set LED initial state. */ 237 led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0; 238 led_dat->cdev.brightness = 239 (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL; 240 241 ret = led_classdev_register(&pdev->dev, &led_dat->cdev); 242 if (ret < 0) 243 return ret; 244 245 return 0; 246 } 247 248 static void delete_ns2_led(struct ns2_led_data *led_dat) 249 { 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 struct ns2_led_priv { 310 int num_leds; 311 struct ns2_led_data leds_data[]; 312 }; 313 314 static inline int sizeof_ns2_led_priv(int num_leds) 315 { 316 return sizeof(struct ns2_led_priv) + 317 (sizeof(struct ns2_led_data) * num_leds); 318 } 319 320 static int ns2_led_probe(struct platform_device *pdev) 321 { 322 struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev); 323 struct ns2_led_priv *priv; 324 int i; 325 int ret; 326 327 #ifdef CONFIG_OF_GPIO 328 if (!pdata) { 329 pdata = devm_kzalloc(&pdev->dev, 330 sizeof(struct ns2_led_platform_data), 331 GFP_KERNEL); 332 if (!pdata) 333 return -ENOMEM; 334 335 ret = ns2_leds_get_of_pdata(&pdev->dev, pdata); 336 if (ret) 337 return ret; 338 } 339 #else 340 if (!pdata) 341 return -EINVAL; 342 #endif /* CONFIG_OF_GPIO */ 343 344 priv = devm_kzalloc(&pdev->dev, 345 sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL); 346 if (!priv) 347 return -ENOMEM; 348 priv->num_leds = pdata->num_leds; 349 350 for (i = 0; i < priv->num_leds; i++) { 351 ret = create_ns2_led(pdev, &priv->leds_data[i], 352 &pdata->leds[i]); 353 if (ret < 0) { 354 for (i = i - 1; i >= 0; i--) 355 delete_ns2_led(&priv->leds_data[i]); 356 return ret; 357 } 358 } 359 360 platform_set_drvdata(pdev, priv); 361 362 return 0; 363 } 364 365 static int ns2_led_remove(struct platform_device *pdev) 366 { 367 int i; 368 struct ns2_led_priv *priv; 369 370 priv = platform_get_drvdata(pdev); 371 372 for (i = 0; i < priv->num_leds; i++) 373 delete_ns2_led(&priv->leds_data[i]); 374 375 return 0; 376 } 377 378 static struct platform_driver ns2_led_driver = { 379 .probe = ns2_led_probe, 380 .remove = ns2_led_remove, 381 .driver = { 382 .name = "leds-ns2", 383 .owner = THIS_MODULE, 384 .of_match_table = of_match_ptr(of_ns2_leds_match), 385 }, 386 }; 387 388 module_platform_driver(ns2_led_driver); 389 390 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>"); 391 MODULE_DESCRIPTION("Network Space v2 LED driver"); 392 MODULE_LICENSE("GPL"); 393 MODULE_ALIAS("platform:leds-ns2"); 394