Thomas Gleixner | c942fdd | 2019-05-27 08:55:06 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
Sean Wang | 216ec6c | 2017-03-20 14:47:26 +0800 | [diff] [blame] | 2 | /* |
| 3 | * LED driver for Mediatek MT6323 PMIC |
| 4 | * |
| 5 | * Copyright (C) 2017 Sean Wang <sean.wang@mediatek.com> |
Sean Wang | 216ec6c | 2017-03-20 14:47:26 +0800 | [diff] [blame] | 6 | */ |
| 7 | #include <linux/kernel.h> |
| 8 | #include <linux/leds.h> |
| 9 | #include <linux/mfd/mt6323/registers.h> |
| 10 | #include <linux/mfd/mt6397/core.h> |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/of.h> |
| 13 | #include <linux/platform_device.h> |
| 14 | #include <linux/regmap.h> |
| 15 | |
| 16 | /* |
| 17 | * Register field for MT6323_TOP_CKPDN0 to enable |
| 18 | * 32K clock common for LED device. |
| 19 | */ |
| 20 | #define MT6323_RG_DRV_32K_CK_PDN BIT(11) |
| 21 | #define MT6323_RG_DRV_32K_CK_PDN_MASK BIT(11) |
| 22 | |
| 23 | /* |
| 24 | * Register field for MT6323_TOP_CKPDN2 to enable |
| 25 | * individual clock for LED device. |
| 26 | */ |
| 27 | #define MT6323_RG_ISINK_CK_PDN(i) BIT(i) |
| 28 | #define MT6323_RG_ISINK_CK_PDN_MASK(i) BIT(i) |
| 29 | |
| 30 | /* |
| 31 | * Register field for MT6323_TOP_CKCON1 to select |
| 32 | * clock source. |
| 33 | */ |
| 34 | #define MT6323_RG_ISINK_CK_SEL_MASK(i) (BIT(10) << (i)) |
| 35 | |
| 36 | /* |
| 37 | * Register for MT6323_ISINK_CON0 to setup the |
| 38 | * duty cycle of the blink. |
| 39 | */ |
| 40 | #define MT6323_ISINK_CON0(i) (MT6323_ISINK0_CON0 + 0x8 * (i)) |
| 41 | #define MT6323_ISINK_DIM_DUTY_MASK (0x1f << 8) |
| 42 | #define MT6323_ISINK_DIM_DUTY(i) (((i) << 8) & \ |
| 43 | MT6323_ISINK_DIM_DUTY_MASK) |
| 44 | |
| 45 | /* Register to setup the period of the blink. */ |
| 46 | #define MT6323_ISINK_CON1(i) (MT6323_ISINK0_CON1 + 0x8 * (i)) |
| 47 | #define MT6323_ISINK_DIM_FSEL_MASK (0xffff) |
| 48 | #define MT6323_ISINK_DIM_FSEL(i) ((i) & MT6323_ISINK_DIM_FSEL_MASK) |
| 49 | |
| 50 | /* Register to control the brightness. */ |
| 51 | #define MT6323_ISINK_CON2(i) (MT6323_ISINK0_CON2 + 0x8 * (i)) |
| 52 | #define MT6323_ISINK_CH_STEP_SHIFT 12 |
| 53 | #define MT6323_ISINK_CH_STEP_MASK (0x7 << 12) |
| 54 | #define MT6323_ISINK_CH_STEP(i) (((i) << 12) & \ |
| 55 | MT6323_ISINK_CH_STEP_MASK) |
| 56 | #define MT6323_ISINK_SFSTR0_TC_MASK (0x3 << 1) |
| 57 | #define MT6323_ISINK_SFSTR0_TC(i) (((i) << 1) & \ |
| 58 | MT6323_ISINK_SFSTR0_TC_MASK) |
| 59 | #define MT6323_ISINK_SFSTR0_EN_MASK BIT(0) |
| 60 | #define MT6323_ISINK_SFSTR0_EN BIT(0) |
| 61 | |
| 62 | /* Register to LED channel enablement. */ |
| 63 | #define MT6323_ISINK_CH_EN_MASK(i) BIT(i) |
| 64 | #define MT6323_ISINK_CH_EN(i) BIT(i) |
| 65 | |
| 66 | #define MT6323_MAX_PERIOD 10000 |
| 67 | #define MT6323_MAX_LEDS 4 |
| 68 | #define MT6323_MAX_BRIGHTNESS 6 |
| 69 | #define MT6323_UNIT_DUTY 3125 |
| 70 | #define MT6323_CAL_HW_DUTY(o, p) DIV_ROUND_CLOSEST((o) * 100000ul,\ |
| 71 | (p) * MT6323_UNIT_DUTY) |
| 72 | |
| 73 | struct mt6323_leds; |
| 74 | |
| 75 | /** |
| 76 | * struct mt6323_led - state container for the LED device |
| 77 | * @id: the identifier in MT6323 LED device |
| 78 | * @parent: the pointer to MT6323 LED controller |
| 79 | * @cdev: LED class device for this LED device |
| 80 | * @current_brightness: current state of the LED device |
| 81 | */ |
| 82 | struct mt6323_led { |
| 83 | int id; |
| 84 | struct mt6323_leds *parent; |
| 85 | struct led_classdev cdev; |
| 86 | enum led_brightness current_brightness; |
| 87 | }; |
| 88 | |
| 89 | /** |
| 90 | * struct mt6323_leds - state container for holding LED controller |
| 91 | * of the driver |
| 92 | * @dev: the device pointer |
| 93 | * @hw: the underlying hardware providing shared |
| 94 | * bus for the register operations |
| 95 | * @lock: the lock among process context |
| 96 | * @led: the array that contains the state of individual |
| 97 | * LED device |
| 98 | */ |
| 99 | struct mt6323_leds { |
| 100 | struct device *dev; |
| 101 | struct mt6397_chip *hw; |
| 102 | /* protect among process context */ |
| 103 | struct mutex lock; |
| 104 | struct mt6323_led *led[MT6323_MAX_LEDS]; |
| 105 | }; |
| 106 | |
| 107 | static int mt6323_led_hw_brightness(struct led_classdev *cdev, |
| 108 | enum led_brightness brightness) |
| 109 | { |
| 110 | struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev); |
| 111 | struct mt6323_leds *leds = led->parent; |
| 112 | struct regmap *regmap = leds->hw->regmap; |
| 113 | u32 con2_mask = 0, con2_val = 0; |
| 114 | int ret; |
| 115 | |
| 116 | /* |
| 117 | * Setup current output for the corresponding |
| 118 | * brightness level. |
| 119 | */ |
| 120 | con2_mask |= MT6323_ISINK_CH_STEP_MASK | |
| 121 | MT6323_ISINK_SFSTR0_TC_MASK | |
| 122 | MT6323_ISINK_SFSTR0_EN_MASK; |
| 123 | con2_val |= MT6323_ISINK_CH_STEP(brightness - 1) | |
| 124 | MT6323_ISINK_SFSTR0_TC(2) | |
| 125 | MT6323_ISINK_SFSTR0_EN; |
| 126 | |
| 127 | ret = regmap_update_bits(regmap, MT6323_ISINK_CON2(led->id), |
| 128 | con2_mask, con2_val); |
| 129 | return ret; |
| 130 | } |
| 131 | |
| 132 | static int mt6323_led_hw_off(struct led_classdev *cdev) |
| 133 | { |
| 134 | struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev); |
| 135 | struct mt6323_leds *leds = led->parent; |
| 136 | struct regmap *regmap = leds->hw->regmap; |
| 137 | unsigned int status; |
| 138 | int ret; |
| 139 | |
| 140 | status = MT6323_ISINK_CH_EN(led->id); |
| 141 | ret = regmap_update_bits(regmap, MT6323_ISINK_EN_CTRL, |
| 142 | MT6323_ISINK_CH_EN_MASK(led->id), ~status); |
| 143 | if (ret < 0) |
| 144 | return ret; |
| 145 | |
| 146 | usleep_range(100, 300); |
| 147 | ret = regmap_update_bits(regmap, MT6323_TOP_CKPDN2, |
| 148 | MT6323_RG_ISINK_CK_PDN_MASK(led->id), |
| 149 | MT6323_RG_ISINK_CK_PDN(led->id)); |
| 150 | if (ret < 0) |
| 151 | return ret; |
| 152 | |
| 153 | return 0; |
| 154 | } |
| 155 | |
| 156 | static enum led_brightness |
| 157 | mt6323_get_led_hw_brightness(struct led_classdev *cdev) |
| 158 | { |
| 159 | struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev); |
| 160 | struct mt6323_leds *leds = led->parent; |
| 161 | struct regmap *regmap = leds->hw->regmap; |
| 162 | unsigned int status; |
| 163 | int ret; |
| 164 | |
| 165 | ret = regmap_read(regmap, MT6323_TOP_CKPDN2, &status); |
| 166 | if (ret < 0) |
| 167 | return ret; |
| 168 | |
| 169 | if (status & MT6323_RG_ISINK_CK_PDN_MASK(led->id)) |
| 170 | return 0; |
| 171 | |
| 172 | ret = regmap_read(regmap, MT6323_ISINK_EN_CTRL, &status); |
| 173 | if (ret < 0) |
| 174 | return ret; |
| 175 | |
| 176 | if (!(status & MT6323_ISINK_CH_EN(led->id))) |
| 177 | return 0; |
| 178 | |
| 179 | ret = regmap_read(regmap, MT6323_ISINK_CON2(led->id), &status); |
| 180 | if (ret < 0) |
| 181 | return ret; |
| 182 | |
| 183 | return ((status & MT6323_ISINK_CH_STEP_MASK) |
| 184 | >> MT6323_ISINK_CH_STEP_SHIFT) + 1; |
| 185 | } |
| 186 | |
| 187 | static int mt6323_led_hw_on(struct led_classdev *cdev, |
| 188 | enum led_brightness brightness) |
| 189 | { |
| 190 | struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev); |
| 191 | struct mt6323_leds *leds = led->parent; |
| 192 | struct regmap *regmap = leds->hw->regmap; |
| 193 | unsigned int status; |
| 194 | int ret; |
| 195 | |
| 196 | /* |
| 197 | * Setup required clock source, enable the corresponding |
| 198 | * clock and channel and let work with continuous blink as |
| 199 | * the default. |
| 200 | */ |
| 201 | ret = regmap_update_bits(regmap, MT6323_TOP_CKCON1, |
| 202 | MT6323_RG_ISINK_CK_SEL_MASK(led->id), 0); |
| 203 | if (ret < 0) |
| 204 | return ret; |
| 205 | |
| 206 | status = MT6323_RG_ISINK_CK_PDN(led->id); |
| 207 | ret = regmap_update_bits(regmap, MT6323_TOP_CKPDN2, |
| 208 | MT6323_RG_ISINK_CK_PDN_MASK(led->id), |
| 209 | ~status); |
| 210 | if (ret < 0) |
| 211 | return ret; |
| 212 | |
| 213 | usleep_range(100, 300); |
| 214 | |
| 215 | ret = regmap_update_bits(regmap, MT6323_ISINK_EN_CTRL, |
| 216 | MT6323_ISINK_CH_EN_MASK(led->id), |
| 217 | MT6323_ISINK_CH_EN(led->id)); |
| 218 | if (ret < 0) |
| 219 | return ret; |
| 220 | |
| 221 | ret = mt6323_led_hw_brightness(cdev, brightness); |
| 222 | if (ret < 0) |
| 223 | return ret; |
| 224 | |
| 225 | ret = regmap_update_bits(regmap, MT6323_ISINK_CON0(led->id), |
| 226 | MT6323_ISINK_DIM_DUTY_MASK, |
| 227 | MT6323_ISINK_DIM_DUTY(31)); |
| 228 | if (ret < 0) |
| 229 | return ret; |
| 230 | |
| 231 | ret = regmap_update_bits(regmap, MT6323_ISINK_CON1(led->id), |
| 232 | MT6323_ISINK_DIM_FSEL_MASK, |
| 233 | MT6323_ISINK_DIM_FSEL(1000)); |
| 234 | if (ret < 0) |
| 235 | return ret; |
| 236 | |
| 237 | return 0; |
| 238 | } |
| 239 | |
| 240 | static int mt6323_led_set_blink(struct led_classdev *cdev, |
| 241 | unsigned long *delay_on, |
| 242 | unsigned long *delay_off) |
| 243 | { |
| 244 | struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev); |
| 245 | struct mt6323_leds *leds = led->parent; |
| 246 | struct regmap *regmap = leds->hw->regmap; |
| 247 | unsigned long period; |
| 248 | u8 duty_hw; |
| 249 | int ret; |
| 250 | |
| 251 | /* |
| 252 | * Units are in ms, if over the hardware able |
| 253 | * to support, fallback into software blink |
| 254 | */ |
| 255 | period = *delay_on + *delay_off; |
| 256 | |
| 257 | if (period > MT6323_MAX_PERIOD) |
| 258 | return -EINVAL; |
| 259 | |
| 260 | /* |
| 261 | * LED subsystem requires a default user |
| 262 | * friendly blink pattern for the LED so using |
| 263 | * 1Hz duty cycle 50% here if without specific |
| 264 | * value delay_on and delay off being assigned. |
| 265 | */ |
| 266 | if (!*delay_on && !*delay_off) { |
| 267 | *delay_on = 500; |
| 268 | *delay_off = 500; |
| 269 | } |
| 270 | |
| 271 | /* |
| 272 | * Calculate duty_hw based on the percentage of period during |
| 273 | * which the led is ON. |
| 274 | */ |
| 275 | duty_hw = MT6323_CAL_HW_DUTY(*delay_on, period); |
| 276 | |
| 277 | /* hardware doesn't support zero duty cycle. */ |
| 278 | if (!duty_hw) |
| 279 | return -EINVAL; |
| 280 | |
| 281 | mutex_lock(&leds->lock); |
| 282 | /* |
| 283 | * Set max_brightness as the software blink behavior |
| 284 | * when no blink brightness. |
| 285 | */ |
| 286 | if (!led->current_brightness) { |
| 287 | ret = mt6323_led_hw_on(cdev, cdev->max_brightness); |
| 288 | if (ret < 0) |
| 289 | goto out; |
| 290 | led->current_brightness = cdev->max_brightness; |
| 291 | } |
| 292 | |
| 293 | ret = regmap_update_bits(regmap, MT6323_ISINK_CON0(led->id), |
| 294 | MT6323_ISINK_DIM_DUTY_MASK, |
| 295 | MT6323_ISINK_DIM_DUTY(duty_hw - 1)); |
| 296 | if (ret < 0) |
| 297 | goto out; |
| 298 | |
| 299 | ret = regmap_update_bits(regmap, MT6323_ISINK_CON1(led->id), |
| 300 | MT6323_ISINK_DIM_FSEL_MASK, |
| 301 | MT6323_ISINK_DIM_FSEL(period - 1)); |
| 302 | out: |
| 303 | mutex_unlock(&leds->lock); |
| 304 | |
| 305 | return ret; |
| 306 | } |
| 307 | |
| 308 | static int mt6323_led_set_brightness(struct led_classdev *cdev, |
| 309 | enum led_brightness brightness) |
| 310 | { |
| 311 | struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev); |
| 312 | struct mt6323_leds *leds = led->parent; |
| 313 | int ret; |
| 314 | |
| 315 | mutex_lock(&leds->lock); |
| 316 | |
| 317 | if (!led->current_brightness && brightness) { |
| 318 | ret = mt6323_led_hw_on(cdev, brightness); |
| 319 | if (ret < 0) |
| 320 | goto out; |
| 321 | } else if (brightness) { |
| 322 | ret = mt6323_led_hw_brightness(cdev, brightness); |
| 323 | if (ret < 0) |
| 324 | goto out; |
| 325 | } else { |
| 326 | ret = mt6323_led_hw_off(cdev); |
| 327 | if (ret < 0) |
| 328 | goto out; |
| 329 | } |
| 330 | |
| 331 | led->current_brightness = brightness; |
| 332 | out: |
| 333 | mutex_unlock(&leds->lock); |
| 334 | |
| 335 | return ret; |
| 336 | } |
| 337 | |
| 338 | static int mt6323_led_set_dt_default(struct led_classdev *cdev, |
| 339 | struct device_node *np) |
| 340 | { |
| 341 | struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev); |
| 342 | const char *state; |
| 343 | int ret = 0; |
| 344 | |
| 345 | led->cdev.name = of_get_property(np, "label", NULL) ? : np->name; |
| 346 | led->cdev.default_trigger = of_get_property(np, |
| 347 | "linux,default-trigger", |
| 348 | NULL); |
| 349 | |
| 350 | state = of_get_property(np, "default-state", NULL); |
| 351 | if (state) { |
| 352 | if (!strcmp(state, "keep")) { |
| 353 | ret = mt6323_get_led_hw_brightness(cdev); |
| 354 | if (ret < 0) |
| 355 | return ret; |
| 356 | led->current_brightness = ret; |
| 357 | ret = 0; |
| 358 | } else if (!strcmp(state, "on")) { |
| 359 | ret = |
| 360 | mt6323_led_set_brightness(cdev, cdev->max_brightness); |
| 361 | } else { |
| 362 | ret = mt6323_led_set_brightness(cdev, LED_OFF); |
| 363 | } |
| 364 | } |
| 365 | |
| 366 | return ret; |
| 367 | } |
| 368 | |
| 369 | static int mt6323_led_probe(struct platform_device *pdev) |
| 370 | { |
| 371 | struct device *dev = &pdev->dev; |
| 372 | struct device_node *np = pdev->dev.of_node; |
| 373 | struct device_node *child; |
| 374 | struct mt6397_chip *hw = dev_get_drvdata(pdev->dev.parent); |
| 375 | struct mt6323_leds *leds; |
| 376 | struct mt6323_led *led; |
| 377 | int ret; |
| 378 | unsigned int status; |
| 379 | u32 reg; |
| 380 | |
| 381 | leds = devm_kzalloc(dev, sizeof(*leds), GFP_KERNEL); |
| 382 | if (!leds) |
| 383 | return -ENOMEM; |
| 384 | |
| 385 | platform_set_drvdata(pdev, leds); |
| 386 | leds->dev = dev; |
| 387 | |
| 388 | /* |
| 389 | * leds->hw points to the underlying bus for the register |
| 390 | * controlled. |
| 391 | */ |
| 392 | leds->hw = hw; |
| 393 | mutex_init(&leds->lock); |
| 394 | |
| 395 | status = MT6323_RG_DRV_32K_CK_PDN; |
| 396 | ret = regmap_update_bits(leds->hw->regmap, MT6323_TOP_CKPDN0, |
| 397 | MT6323_RG_DRV_32K_CK_PDN_MASK, ~status); |
| 398 | if (ret < 0) { |
| 399 | dev_err(leds->dev, |
| 400 | "Failed to update MT6323_TOP_CKPDN0 Register\n"); |
| 401 | return ret; |
| 402 | } |
| 403 | |
| 404 | for_each_available_child_of_node(np, child) { |
| 405 | ret = of_property_read_u32(child, "reg", ®); |
| 406 | if (ret) { |
| 407 | dev_err(dev, "Failed to read led 'reg' property\n"); |
| 408 | goto put_child_node; |
| 409 | } |
| 410 | |
Dan Carpenter | ac57245 | 2017-03-23 13:40:49 +0300 | [diff] [blame] | 411 | if (reg >= MT6323_MAX_LEDS || leds->led[reg]) { |
Sean Wang | 216ec6c | 2017-03-20 14:47:26 +0800 | [diff] [blame] | 412 | dev_err(dev, "Invalid led reg %u\n", reg); |
| 413 | ret = -EINVAL; |
| 414 | goto put_child_node; |
| 415 | } |
| 416 | |
| 417 | led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL); |
| 418 | if (!led) { |
| 419 | ret = -ENOMEM; |
| 420 | goto put_child_node; |
| 421 | } |
| 422 | |
| 423 | leds->led[reg] = led; |
| 424 | leds->led[reg]->id = reg; |
| 425 | leds->led[reg]->cdev.max_brightness = MT6323_MAX_BRIGHTNESS; |
| 426 | leds->led[reg]->cdev.brightness_set_blocking = |
| 427 | mt6323_led_set_brightness; |
| 428 | leds->led[reg]->cdev.blink_set = mt6323_led_set_blink; |
| 429 | leds->led[reg]->cdev.brightness_get = |
| 430 | mt6323_get_led_hw_brightness; |
| 431 | leds->led[reg]->parent = leds; |
| 432 | |
| 433 | ret = mt6323_led_set_dt_default(&leds->led[reg]->cdev, child); |
| 434 | if (ret < 0) { |
| 435 | dev_err(leds->dev, |
| 436 | "Failed to LED set default from devicetree\n"); |
| 437 | goto put_child_node; |
| 438 | } |
| 439 | |
| 440 | ret = devm_led_classdev_register(dev, &leds->led[reg]->cdev); |
| 441 | if (ret) { |
| 442 | dev_err(&pdev->dev, "Failed to register LED: %d\n", |
| 443 | ret); |
| 444 | goto put_child_node; |
| 445 | } |
| 446 | leds->led[reg]->cdev.dev->of_node = child; |
| 447 | } |
| 448 | |
| 449 | return 0; |
| 450 | |
| 451 | put_child_node: |
| 452 | of_node_put(child); |
| 453 | return ret; |
| 454 | } |
| 455 | |
| 456 | static int mt6323_led_remove(struct platform_device *pdev) |
| 457 | { |
| 458 | struct mt6323_leds *leds = platform_get_drvdata(pdev); |
| 459 | int i; |
| 460 | |
| 461 | /* Turn the LEDs off on driver removal. */ |
| 462 | for (i = 0 ; leds->led[i] ; i++) |
| 463 | mt6323_led_hw_off(&leds->led[i]->cdev); |
| 464 | |
| 465 | regmap_update_bits(leds->hw->regmap, MT6323_TOP_CKPDN0, |
| 466 | MT6323_RG_DRV_32K_CK_PDN_MASK, |
| 467 | MT6323_RG_DRV_32K_CK_PDN); |
| 468 | |
| 469 | mutex_destroy(&leds->lock); |
| 470 | |
| 471 | return 0; |
| 472 | } |
| 473 | |
| 474 | static const struct of_device_id mt6323_led_dt_match[] = { |
| 475 | { .compatible = "mediatek,mt6323-led" }, |
| 476 | {}, |
| 477 | }; |
| 478 | MODULE_DEVICE_TABLE(of, mt6323_led_dt_match); |
| 479 | |
| 480 | static struct platform_driver mt6323_led_driver = { |
| 481 | .probe = mt6323_led_probe, |
| 482 | .remove = mt6323_led_remove, |
| 483 | .driver = { |
| 484 | .name = "mt6323-led", |
| 485 | .of_match_table = mt6323_led_dt_match, |
| 486 | }, |
| 487 | }; |
| 488 | |
| 489 | module_platform_driver(mt6323_led_driver); |
| 490 | |
| 491 | MODULE_DESCRIPTION("LED driver for Mediatek MT6323 PMIC"); |
| 492 | MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>"); |
| 493 | MODULE_LICENSE("GPL"); |