Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 1 | /* |
| 2 | * LED driver for WM8350 driven LEDS. |
| 3 | * |
| 4 | * Copyright(C) 2007, 2008 Wolfson Microelectronics PLC. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | */ |
| 11 | |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/platform_device.h> |
| 15 | #include <linux/leds.h> |
| 16 | #include <linux/err.h> |
| 17 | #include <linux/mfd/wm8350/pmic.h> |
| 18 | #include <linux/regulator/consumer.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 19 | #include <linux/slab.h> |
Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 20 | |
| 21 | /* Microamps */ |
| 22 | static const int isink_cur[] = { |
| 23 | 4, |
| 24 | 5, |
| 25 | 6, |
| 26 | 7, |
| 27 | 8, |
| 28 | 10, |
| 29 | 11, |
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| 62 | 3487, |
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| 64 | 4932, |
| 65 | 5865, |
| 66 | 6975, |
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| 70 | 13949, |
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| 75 | 33178, |
| 76 | 39455, |
| 77 | 46920, |
| 78 | 55798, |
| 79 | 66355, |
| 80 | 78910, |
| 81 | 93840, |
| 82 | 111596, |
| 83 | 132710, |
| 84 | 157820, |
| 85 | 187681, |
| 86 | 223191 |
| 87 | }; |
| 88 | |
| 89 | #define to_wm8350_led(led_cdev) \ |
| 90 | container_of(led_cdev, struct wm8350_led, cdev) |
| 91 | |
| 92 | static void wm8350_led_enable(struct wm8350_led *led) |
| 93 | { |
| 94 | int ret; |
| 95 | |
| 96 | if (led->enabled) |
| 97 | return; |
| 98 | |
| 99 | ret = regulator_enable(led->isink); |
| 100 | if (ret != 0) { |
| 101 | dev_err(led->cdev.dev, "Failed to enable ISINK: %d\n", ret); |
| 102 | return; |
| 103 | } |
| 104 | |
| 105 | ret = regulator_enable(led->dcdc); |
| 106 | if (ret != 0) { |
| 107 | dev_err(led->cdev.dev, "Failed to enable DCDC: %d\n", ret); |
| 108 | regulator_disable(led->isink); |
| 109 | return; |
| 110 | } |
| 111 | |
| 112 | led->enabled = 1; |
| 113 | } |
| 114 | |
| 115 | static void wm8350_led_disable(struct wm8350_led *led) |
| 116 | { |
| 117 | int ret; |
| 118 | |
| 119 | if (!led->enabled) |
| 120 | return; |
| 121 | |
| 122 | ret = regulator_disable(led->dcdc); |
| 123 | if (ret != 0) { |
| 124 | dev_err(led->cdev.dev, "Failed to disable DCDC: %d\n", ret); |
| 125 | return; |
| 126 | } |
| 127 | |
| 128 | ret = regulator_disable(led->isink); |
| 129 | if (ret != 0) { |
| 130 | dev_err(led->cdev.dev, "Failed to disable ISINK: %d\n", ret); |
| 131 | regulator_enable(led->dcdc); |
| 132 | return; |
| 133 | } |
| 134 | |
| 135 | led->enabled = 0; |
| 136 | } |
| 137 | |
| 138 | static void led_work(struct work_struct *work) |
| 139 | { |
| 140 | struct wm8350_led *led = container_of(work, struct wm8350_led, work); |
| 141 | int ret; |
| 142 | int uA; |
| 143 | unsigned long flags; |
| 144 | |
| 145 | mutex_lock(&led->mutex); |
| 146 | |
| 147 | spin_lock_irqsave(&led->value_lock, flags); |
| 148 | |
| 149 | if (led->value == LED_OFF) { |
| 150 | spin_unlock_irqrestore(&led->value_lock, flags); |
| 151 | wm8350_led_disable(led); |
| 152 | goto out; |
| 153 | } |
| 154 | |
| 155 | /* This scales linearly into the index of valid current |
| 156 | * settings which results in a linear scaling of perceived |
| 157 | * brightness due to the non-linear current settings provided |
| 158 | * by the hardware. |
| 159 | */ |
| 160 | uA = (led->max_uA_index * led->value) / LED_FULL; |
| 161 | spin_unlock_irqrestore(&led->value_lock, flags); |
| 162 | BUG_ON(uA >= ARRAY_SIZE(isink_cur)); |
| 163 | |
| 164 | ret = regulator_set_current_limit(led->isink, isink_cur[uA], |
| 165 | isink_cur[uA]); |
| 166 | if (ret != 0) |
| 167 | dev_err(led->cdev.dev, "Failed to set %duA: %d\n", |
| 168 | isink_cur[uA], ret); |
| 169 | |
| 170 | wm8350_led_enable(led); |
| 171 | |
| 172 | out: |
| 173 | mutex_unlock(&led->mutex); |
| 174 | } |
| 175 | |
| 176 | static void wm8350_led_set(struct led_classdev *led_cdev, |
| 177 | enum led_brightness value) |
| 178 | { |
| 179 | struct wm8350_led *led = to_wm8350_led(led_cdev); |
| 180 | unsigned long flags; |
| 181 | |
| 182 | spin_lock_irqsave(&led->value_lock, flags); |
| 183 | led->value = value; |
| 184 | schedule_work(&led->work); |
| 185 | spin_unlock_irqrestore(&led->value_lock, flags); |
| 186 | } |
| 187 | |
Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 188 | static void wm8350_led_shutdown(struct platform_device *pdev) |
| 189 | { |
| 190 | struct wm8350_led *led = platform_get_drvdata(pdev); |
| 191 | |
| 192 | mutex_lock(&led->mutex); |
| 193 | led->value = LED_OFF; |
| 194 | wm8350_led_disable(led); |
| 195 | mutex_unlock(&led->mutex); |
| 196 | } |
| 197 | |
| 198 | static int wm8350_led_probe(struct platform_device *pdev) |
| 199 | { |
| 200 | struct regulator *isink, *dcdc; |
| 201 | struct wm8350_led *led; |
| 202 | struct wm8350_led_platform_data *pdata = pdev->dev.platform_data; |
| 203 | int ret, i; |
| 204 | |
| 205 | if (pdata == NULL) { |
| 206 | dev_err(&pdev->dev, "no platform data\n"); |
| 207 | return -ENODEV; |
| 208 | } |
| 209 | |
| 210 | if (pdata->max_uA < isink_cur[0]) { |
| 211 | dev_err(&pdev->dev, "Invalid maximum current %duA\n", |
| 212 | pdata->max_uA); |
| 213 | return -EINVAL; |
| 214 | } |
| 215 | |
| 216 | isink = regulator_get(&pdev->dev, "led_isink"); |
| 217 | if (IS_ERR(isink)) { |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame^] | 218 | printk(KERN_ERR "%s: can't get ISINK\n", __func__); |
Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 219 | return PTR_ERR(isink); |
| 220 | } |
| 221 | |
| 222 | dcdc = regulator_get(&pdev->dev, "led_vcc"); |
| 223 | if (IS_ERR(dcdc)) { |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame^] | 224 | printk(KERN_ERR "%s: can't get DCDC\n", __func__); |
Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 225 | ret = PTR_ERR(dcdc); |
| 226 | goto err_isink; |
| 227 | } |
| 228 | |
| 229 | led = kzalloc(sizeof(*led), GFP_KERNEL); |
| 230 | if (led == NULL) { |
| 231 | ret = -ENOMEM; |
| 232 | goto err_dcdc; |
| 233 | } |
| 234 | |
| 235 | led->cdev.brightness_set = wm8350_led_set; |
| 236 | led->cdev.default_trigger = pdata->default_trigger; |
| 237 | led->cdev.name = pdata->name; |
Richard Purdie | 859cb7f | 2009-01-08 17:55:03 +0000 | [diff] [blame] | 238 | led->cdev.flags |= LED_CORE_SUSPENDRESUME; |
Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 239 | led->enabled = regulator_is_enabled(isink); |
| 240 | led->isink = isink; |
| 241 | led->dcdc = dcdc; |
| 242 | |
| 243 | for (i = 0; i < ARRAY_SIZE(isink_cur) - 1; i++) |
| 244 | if (isink_cur[i] >= pdata->max_uA) |
| 245 | break; |
| 246 | led->max_uA_index = i; |
| 247 | if (pdata->max_uA != isink_cur[i]) |
| 248 | dev_warn(&pdev->dev, |
| 249 | "Maximum current %duA is not directly supported," |
| 250 | " check platform data\n", |
| 251 | pdata->max_uA); |
| 252 | |
| 253 | spin_lock_init(&led->value_lock); |
| 254 | mutex_init(&led->mutex); |
| 255 | INIT_WORK(&led->work, led_work); |
| 256 | led->value = LED_OFF; |
| 257 | platform_set_drvdata(pdev, led); |
| 258 | |
| 259 | ret = led_classdev_register(&pdev->dev, &led->cdev); |
| 260 | if (ret < 0) |
| 261 | goto err_led; |
| 262 | |
| 263 | return 0; |
| 264 | |
| 265 | err_led: |
| 266 | kfree(led); |
| 267 | err_dcdc: |
| 268 | regulator_put(dcdc); |
| 269 | err_isink: |
| 270 | regulator_put(isink); |
| 271 | return ret; |
| 272 | } |
| 273 | |
| 274 | static int wm8350_led_remove(struct platform_device *pdev) |
| 275 | { |
| 276 | struct wm8350_led *led = platform_get_drvdata(pdev); |
| 277 | |
| 278 | led_classdev_unregister(&led->cdev); |
Tejun Heo | 99ef212 | 2010-12-24 15:59:07 +0100 | [diff] [blame] | 279 | flush_work_sync(&led->work); |
Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 280 | wm8350_led_disable(led); |
| 281 | regulator_put(led->dcdc); |
| 282 | regulator_put(led->isink); |
| 283 | kfree(led); |
| 284 | return 0; |
| 285 | } |
| 286 | |
| 287 | static struct platform_driver wm8350_led_driver = { |
| 288 | .driver = { |
| 289 | .name = "wm8350-led", |
| 290 | .owner = THIS_MODULE, |
| 291 | }, |
| 292 | .probe = wm8350_led_probe, |
| 293 | .remove = wm8350_led_remove, |
| 294 | .shutdown = wm8350_led_shutdown, |
Mark Brown | 0081e80 | 2008-12-04 16:52:33 +0000 | [diff] [blame] | 295 | }; |
| 296 | |
| 297 | static int __devinit wm8350_led_init(void) |
| 298 | { |
| 299 | return platform_driver_register(&wm8350_led_driver); |
| 300 | } |
| 301 | module_init(wm8350_led_init); |
| 302 | |
| 303 | static void wm8350_led_exit(void) |
| 304 | { |
| 305 | platform_driver_unregister(&wm8350_led_driver); |
| 306 | } |
| 307 | module_exit(wm8350_led_exit); |
| 308 | |
| 309 | MODULE_AUTHOR("Mark Brown"); |
| 310 | MODULE_DESCRIPTION("WM8350 LED driver"); |
| 311 | MODULE_LICENSE("GPL"); |
| 312 | MODULE_ALIAS("platform:wm8350-led"); |