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1// SPDX-License-Identifier: GPL-2.0+2//3// Driver for Panasonic AN30259A 3-channel LED driver4//5// Copyright (c) 2018 Simon Shields <simon@lineageos.org>6//7// Datasheet:8// https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf9 10#include <linux/i2c.h>11#include <linux/leds.h>12#include <linux/module.h>13#include <linux/mutex.h>14#include <linux/of.h>15#include <linux/regmap.h>16 17#define AN30259A_MAX_LEDS 318 19#define AN30259A_REG_SRESET 0x0020#define AN30259A_LED_SRESET BIT(0)21 22/* LED power registers */23#define AN30259A_REG_LED_ON 0x0124#define AN30259A_LED_EN(x) BIT((x) - 1)25#define AN30259A_LED_SLOPE(x) BIT(((x) - 1) + 4)26 27#define AN30259A_REG_LEDCC(x) (0x03 + ((x) - 1))28 29/* slope control registers */30#define AN30259A_REG_SLOPE(x) (0x06 + ((x) - 1))31#define AN30259A_LED_SLOPETIME1(x) (x)32#define AN30259A_LED_SLOPETIME2(x) ((x) << 4)33 34#define AN30259A_REG_LEDCNT1(x) (0x09 + (4 * ((x) - 1)))35#define AN30259A_LED_DUTYMAX(x) ((x) << 4)36#define AN30259A_LED_DUTYMID(x) (x)37 38#define AN30259A_REG_LEDCNT2(x) (0x0A + (4 * ((x) - 1)))39#define AN30259A_LED_DELAY(x) ((x) << 4)40#define AN30259A_LED_DUTYMIN(x) (x)41 42/* detention time control (length of each slope step) */43#define AN30259A_REG_LEDCNT3(x) (0x0B + (4 * ((x) - 1)))44#define AN30259A_LED_DT1(x) (x)45#define AN30259A_LED_DT2(x) ((x) << 4)46 47#define AN30259A_REG_LEDCNT4(x) (0x0C + (4 * ((x) - 1)))48#define AN30259A_LED_DT3(x) (x)49#define AN30259A_LED_DT4(x) ((x) << 4)50 51#define AN30259A_REG_MAX 0x1452 53#define AN30259A_BLINK_MAX_TIME 7500 /* ms */54#define AN30259A_SLOPE_RESOLUTION 500 /* ms */55 56#define AN30259A_NAME "an30259a"57 58struct an30259a;59 60struct an30259a_led {61 struct an30259a *chip;62 struct fwnode_handle *fwnode;63 struct led_classdev cdev;64 u32 num;65 enum led_default_state default_state;66 bool sloping;67};68 69struct an30259a {70 struct mutex mutex; /* held when writing to registers */71 struct i2c_client *client;72 struct an30259a_led leds[AN30259A_MAX_LEDS];73 struct regmap *regmap;74 int num_leds;75};76 77static int an30259a_brightness_set(struct led_classdev *cdev,78 enum led_brightness brightness)79{80 struct an30259a_led *led;81 int ret;82 unsigned int led_on;83 84 led = container_of(cdev, struct an30259a_led, cdev);85 mutex_lock(&led->chip->mutex);86 87 ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);88 if (ret)89 goto error;90 91 switch (brightness) {92 case LED_OFF:93 led_on &= ~AN30259A_LED_EN(led->num);94 led_on &= ~AN30259A_LED_SLOPE(led->num);95 led->sloping = false;96 break;97 default:98 led_on |= AN30259A_LED_EN(led->num);99 if (led->sloping)100 led_on |= AN30259A_LED_SLOPE(led->num);101 ret = regmap_write(led->chip->regmap,102 AN30259A_REG_LEDCNT1(led->num),103 AN30259A_LED_DUTYMAX(0xf) |104 AN30259A_LED_DUTYMID(0xf));105 if (ret)106 goto error;107 break;108 }109 110 ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);111 if (ret)112 goto error;113 114 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCC(led->num),115 brightness);116 117error:118 mutex_unlock(&led->chip->mutex);119 120 return ret;121}122 123static int an30259a_blink_set(struct led_classdev *cdev,124 unsigned long *delay_off, unsigned long *delay_on)125{126 struct an30259a_led *led;127 int ret, num;128 unsigned int led_on;129 unsigned long off = *delay_off, on = *delay_on;130 131 led = container_of(cdev, struct an30259a_led, cdev);132 133 mutex_lock(&led->chip->mutex);134 num = led->num;135 136 /* slope time can only be a multiple of 500ms. */137 if (off % AN30259A_SLOPE_RESOLUTION || on % AN30259A_SLOPE_RESOLUTION) {138 ret = -EINVAL;139 goto error;140 }141 142 /* up to a maximum of 7500ms. */143 if (off > AN30259A_BLINK_MAX_TIME || on > AN30259A_BLINK_MAX_TIME) {144 ret = -EINVAL;145 goto error;146 }147 148 /* if no blink specified, default to 1 Hz. */149 if (!off && !on) {150 *delay_off = off = 500;151 *delay_on = on = 500;152 }153 154 /* convert into values the HW will understand. */155 off /= AN30259A_SLOPE_RESOLUTION;156 on /= AN30259A_SLOPE_RESOLUTION;157 158 /* duty min should be zero (=off), delay should be zero. */159 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT2(num),160 AN30259A_LED_DELAY(0) | AN30259A_LED_DUTYMIN(0));161 if (ret)162 goto error;163 164 /* reset detention time (no "breathing" effect). */165 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT3(num),166 AN30259A_LED_DT1(0) | AN30259A_LED_DT2(0));167 if (ret)168 goto error;169 ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT4(num),170 AN30259A_LED_DT3(0) | AN30259A_LED_DT4(0));171 if (ret)172 goto error;173 174 /* slope time controls on/off cycle length. */175 ret = regmap_write(led->chip->regmap, AN30259A_REG_SLOPE(num),176 AN30259A_LED_SLOPETIME1(off) |177 AN30259A_LED_SLOPETIME2(on));178 if (ret)179 goto error;180 181 /* Finally, enable slope mode. */182 ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);183 if (ret)184 goto error;185 186 led_on |= AN30259A_LED_SLOPE(num) | AN30259A_LED_EN(led->num);187 188 ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);189 190 if (!ret)191 led->sloping = true;192error:193 mutex_unlock(&led->chip->mutex);194 195 return ret;196}197 198static int an30259a_dt_init(struct i2c_client *client,199 struct an30259a *chip)200{201 struct device_node *np = dev_of_node(&client->dev), *child;202 int count, ret;203 int i = 0;204 struct an30259a_led *led;205 206 count = of_get_available_child_count(np);207 if (!count || count > AN30259A_MAX_LEDS)208 return -EINVAL;209 210 for_each_available_child_of_node(np, child) {211 u32 source;212 213 ret = of_property_read_u32(child, "reg", &source);214 if (ret != 0 || !source || source > AN30259A_MAX_LEDS) {215 dev_err(&client->dev, "Couldn't read LED address: %d\n",216 ret);217 count--;218 continue;219 }220 221 led = &chip->leds[i];222 223 led->num = source;224 led->chip = chip;225 led->fwnode = of_fwnode_handle(child);226 led->default_state = led_init_default_state_get(led->fwnode);227 228 i++;229 }230 231 if (!count)232 return -EINVAL;233 234 chip->num_leds = i;235 236 return 0;237}238 239static const struct regmap_config an30259a_regmap_config = {240 .reg_bits = 8,241 .val_bits = 8,242 .max_register = AN30259A_REG_MAX,243};244 245static void an30259a_init_default_state(struct an30259a_led *led)246{247 struct an30259a *chip = led->chip;248 int led_on, err;249 250 switch (led->default_state) {251 case LEDS_DEFSTATE_ON:252 led->cdev.brightness = LED_FULL;253 break;254 case LEDS_DEFSTATE_KEEP:255 err = regmap_read(chip->regmap, AN30259A_REG_LED_ON, &led_on);256 if (err)257 break;258 259 if (!(led_on & AN30259A_LED_EN(led->num))) {260 led->cdev.brightness = LED_OFF;261 break;262 }263 regmap_read(chip->regmap, AN30259A_REG_LEDCC(led->num),264 &led->cdev.brightness);265 break;266 default:267 led->cdev.brightness = LED_OFF;268 }269 270 an30259a_brightness_set(&led->cdev, led->cdev.brightness);271}272 273static int an30259a_probe(struct i2c_client *client)274{275 struct an30259a *chip;276 int i, err;277 278 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);279 if (!chip)280 return -ENOMEM;281 282 err = an30259a_dt_init(client, chip);283 if (err < 0)284 return err;285 286 err = devm_mutex_init(&client->dev, &chip->mutex);287 if (err)288 return err;289 290 chip->client = client;291 i2c_set_clientdata(client, chip);292 293 chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config);294 295 if (IS_ERR(chip->regmap)) {296 err = PTR_ERR(chip->regmap);297 dev_err(&client->dev, "Failed to allocate register map: %d\n",298 err);299 goto exit;300 }301 302 for (i = 0; i < chip->num_leds; i++) {303 struct led_init_data init_data = {};304 305 an30259a_init_default_state(&chip->leds[i]);306 chip->leds[i].cdev.brightness_set_blocking =307 an30259a_brightness_set;308 chip->leds[i].cdev.blink_set = an30259a_blink_set;309 310 init_data.fwnode = chip->leds[i].fwnode;311 init_data.devicename = AN30259A_NAME;312 init_data.default_label = ":";313 314 err = devm_led_classdev_register_ext(&client->dev,315 &chip->leds[i].cdev,316 &init_data);317 if (err < 0)318 goto exit;319 }320 return 0;321 322exit:323 return err;324}325 326static const struct of_device_id an30259a_match_table[] = {327 { .compatible = "panasonic,an30259a", },328 { /* sentinel */ },329};330 331MODULE_DEVICE_TABLE(of, an30259a_match_table);332 333static const struct i2c_device_id an30259a_id[] = {334 { "an30259a" },335 { /* sentinel */ }336};337MODULE_DEVICE_TABLE(i2c, an30259a_id);338 339static struct i2c_driver an30259a_driver = {340 .driver = {341 .name = "leds-an30259a",342 .of_match_table = an30259a_match_table,343 },344 .probe = an30259a_probe,345 .id_table = an30259a_id,346};347 348module_i2c_driver(an30259a_driver);349 350MODULE_AUTHOR("Simon Shields <simon@lineageos.org>");351MODULE_DESCRIPTION("AN30259A LED driver");352MODULE_LICENSE("GPL v2");353