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1// SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0-or-later2/*3 * Dell Wyse 3020 a.k.a. "Ariel" Embedded Controller LED Driver4 *5 * Copyright (C) 2020 Lubomir Rintel6 */7 8#include <linux/module.h>9#include <linux/leds.h>10#include <linux/platform_device.h>11#include <linux/regmap.h>12 13enum ec_index {14 EC_BLUE_LED = 0x01,15 EC_AMBER_LED = 0x02,16 EC_GREEN_LED = 0x03,17};18 19enum {20 EC_LED_OFF = 0x00,21 EC_LED_STILL = 0x01,22 EC_LED_FADE = 0x02,23 EC_LED_BLINK = 0x03,24};25 26struct ariel_led {27 struct regmap *ec_ram;28 enum ec_index ec_index;29 struct led_classdev led_cdev;30};31 32#define led_cdev_to_ariel_led(c) container_of(c, struct ariel_led, led_cdev)33 34static enum led_brightness ariel_led_get(struct led_classdev *led_cdev)35{36 struct ariel_led *led = led_cdev_to_ariel_led(led_cdev);37 unsigned int led_status = 0;38 39 if (regmap_read(led->ec_ram, led->ec_index, &led_status))40 return LED_OFF;41 42 if (led_status == EC_LED_STILL)43 return LED_FULL;44 else45 return LED_OFF;46}47 48static void ariel_led_set(struct led_classdev *led_cdev,49 enum led_brightness brightness)50{51 struct ariel_led *led = led_cdev_to_ariel_led(led_cdev);52 53 if (brightness == LED_OFF)54 regmap_write(led->ec_ram, led->ec_index, EC_LED_OFF);55 else56 regmap_write(led->ec_ram, led->ec_index, EC_LED_STILL);57}58 59static int ariel_blink_set(struct led_classdev *led_cdev,60 unsigned long *delay_on, unsigned long *delay_off)61{62 struct ariel_led *led = led_cdev_to_ariel_led(led_cdev);63 64 if (*delay_on == 0 && *delay_off == 0)65 return -EINVAL;66 67 if (*delay_on == 0) {68 regmap_write(led->ec_ram, led->ec_index, EC_LED_OFF);69 } else if (*delay_off == 0) {70 regmap_write(led->ec_ram, led->ec_index, EC_LED_STILL);71 } else {72 *delay_on = 500;73 *delay_off = 500;74 regmap_write(led->ec_ram, led->ec_index, EC_LED_BLINK);75 }76 77 return 0;78}79 80#define NLEDS 381 82static int ariel_led_probe(struct platform_device *pdev)83{84 struct device *dev = &pdev->dev;85 struct ariel_led *leds;86 struct regmap *ec_ram;87 int ret;88 int i;89 90 ec_ram = dev_get_regmap(dev->parent, "ec_ram");91 if (!ec_ram)92 return -ENODEV;93 94 leds = devm_kcalloc(dev, NLEDS, sizeof(*leds), GFP_KERNEL);95 if (!leds)96 return -ENOMEM;97 98 leds[0].ec_index = EC_BLUE_LED;99 leds[0].led_cdev.name = "blue:power";100 leds[0].led_cdev.default_trigger = "default-on";101 102 leds[1].ec_index = EC_AMBER_LED;103 leds[1].led_cdev.name = "amber:status";104 105 leds[2].ec_index = EC_GREEN_LED;106 leds[2].led_cdev.name = "green:status";107 leds[2].led_cdev.default_trigger = "default-on";108 109 for (i = 0; i < NLEDS; i++) {110 leds[i].ec_ram = ec_ram;111 leds[i].led_cdev.brightness_get = ariel_led_get;112 leds[i].led_cdev.brightness_set = ariel_led_set;113 leds[i].led_cdev.blink_set = ariel_blink_set;114 115 ret = devm_led_classdev_register(dev, &leds[i].led_cdev);116 if (ret)117 return ret;118 }119 120 return 0;121}122 123static struct platform_driver ariel_led_driver = {124 .probe = ariel_led_probe,125 .driver = {126 .name = "dell-wyse-ariel-led",127 },128};129module_platform_driver(ariel_led_driver);130 131MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");132MODULE_DESCRIPTION("Dell Wyse 3020 Status LEDs Driver");133MODULE_LICENSE("Dual BSD/GPL");134