1*4882a593Smuzhiyun // SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Dell Wyse 3020 a.k.a. "Ariel" Embedded Controller LED Driver
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2020 Lubomir Rintel
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/module.h>
9*4882a593Smuzhiyun #include <linux/leds.h>
10*4882a593Smuzhiyun #include <linux/regmap.h>
11*4882a593Smuzhiyun #include <linux/of_platform.h>
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun enum ec_index {
14*4882a593Smuzhiyun EC_BLUE_LED = 0x01,
15*4882a593Smuzhiyun EC_AMBER_LED = 0x02,
16*4882a593Smuzhiyun EC_GREEN_LED = 0x03,
17*4882a593Smuzhiyun };
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun enum {
20*4882a593Smuzhiyun EC_LED_OFF = 0x00,
21*4882a593Smuzhiyun EC_LED_STILL = 0x01,
22*4882a593Smuzhiyun EC_LED_FADE = 0x02,
23*4882a593Smuzhiyun EC_LED_BLINK = 0x03,
24*4882a593Smuzhiyun };
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun struct ariel_led {
27*4882a593Smuzhiyun struct regmap *ec_ram;
28*4882a593Smuzhiyun enum ec_index ec_index;
29*4882a593Smuzhiyun struct led_classdev led_cdev;
30*4882a593Smuzhiyun };
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun #define led_cdev_to_ariel_led(c) container_of(c, struct ariel_led, led_cdev)
33*4882a593Smuzhiyun
ariel_led_get(struct led_classdev * led_cdev)34*4882a593Smuzhiyun static enum led_brightness ariel_led_get(struct led_classdev *led_cdev)
35*4882a593Smuzhiyun {
36*4882a593Smuzhiyun struct ariel_led *led = led_cdev_to_ariel_led(led_cdev);
37*4882a593Smuzhiyun unsigned int led_status = 0;
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun if (regmap_read(led->ec_ram, led->ec_index, &led_status))
40*4882a593Smuzhiyun return LED_OFF;
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun if (led_status == EC_LED_STILL)
43*4882a593Smuzhiyun return LED_FULL;
44*4882a593Smuzhiyun else
45*4882a593Smuzhiyun return LED_OFF;
46*4882a593Smuzhiyun }
47*4882a593Smuzhiyun
ariel_led_set(struct led_classdev * led_cdev,enum led_brightness brightness)48*4882a593Smuzhiyun static void ariel_led_set(struct led_classdev *led_cdev,
49*4882a593Smuzhiyun enum led_brightness brightness)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun struct ariel_led *led = led_cdev_to_ariel_led(led_cdev);
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun if (brightness == LED_OFF)
54*4882a593Smuzhiyun regmap_write(led->ec_ram, led->ec_index, EC_LED_OFF);
55*4882a593Smuzhiyun else
56*4882a593Smuzhiyun regmap_write(led->ec_ram, led->ec_index, EC_LED_STILL);
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
ariel_blink_set(struct led_classdev * led_cdev,unsigned long * delay_on,unsigned long * delay_off)59*4882a593Smuzhiyun static int ariel_blink_set(struct led_classdev *led_cdev,
60*4882a593Smuzhiyun unsigned long *delay_on, unsigned long *delay_off)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun struct ariel_led *led = led_cdev_to_ariel_led(led_cdev);
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun if (*delay_on == 0 && *delay_off == 0)
65*4882a593Smuzhiyun return -EINVAL;
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun if (*delay_on == 0) {
68*4882a593Smuzhiyun regmap_write(led->ec_ram, led->ec_index, EC_LED_OFF);
69*4882a593Smuzhiyun } else if (*delay_off == 0) {
70*4882a593Smuzhiyun regmap_write(led->ec_ram, led->ec_index, EC_LED_STILL);
71*4882a593Smuzhiyun } else {
72*4882a593Smuzhiyun *delay_on = 500;
73*4882a593Smuzhiyun *delay_off = 500;
74*4882a593Smuzhiyun regmap_write(led->ec_ram, led->ec_index, EC_LED_BLINK);
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun return 0;
78*4882a593Smuzhiyun }
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun #define NLEDS 3
81*4882a593Smuzhiyun
ariel_led_probe(struct platform_device * pdev)82*4882a593Smuzhiyun static int ariel_led_probe(struct platform_device *pdev)
83*4882a593Smuzhiyun {
84*4882a593Smuzhiyun struct device *dev = &pdev->dev;
85*4882a593Smuzhiyun struct ariel_led *leds;
86*4882a593Smuzhiyun struct regmap *ec_ram;
87*4882a593Smuzhiyun int ret;
88*4882a593Smuzhiyun int i;
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun ec_ram = dev_get_regmap(dev->parent, "ec_ram");
91*4882a593Smuzhiyun if (!ec_ram)
92*4882a593Smuzhiyun return -ENODEV;
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun leds = devm_kcalloc(dev, NLEDS, sizeof(*leds), GFP_KERNEL);
95*4882a593Smuzhiyun if (!leds)
96*4882a593Smuzhiyun return -ENOMEM;
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun leds[0].ec_index = EC_BLUE_LED;
99*4882a593Smuzhiyun leds[0].led_cdev.name = "blue:power",
100*4882a593Smuzhiyun leds[0].led_cdev.default_trigger = "default-on";
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun leds[1].ec_index = EC_AMBER_LED;
103*4882a593Smuzhiyun leds[1].led_cdev.name = "amber:status",
104*4882a593Smuzhiyun
105*4882a593Smuzhiyun leds[2].ec_index = EC_GREEN_LED;
106*4882a593Smuzhiyun leds[2].led_cdev.name = "green:status",
107*4882a593Smuzhiyun leds[2].led_cdev.default_trigger = "default-on";
108*4882a593Smuzhiyun
109*4882a593Smuzhiyun for (i = 0; i < NLEDS; i++) {
110*4882a593Smuzhiyun leds[i].ec_ram = ec_ram;
111*4882a593Smuzhiyun leds[i].led_cdev.brightness_get = ariel_led_get;
112*4882a593Smuzhiyun leds[i].led_cdev.brightness_set = ariel_led_set;
113*4882a593Smuzhiyun leds[i].led_cdev.blink_set = ariel_blink_set;
114*4882a593Smuzhiyun
115*4882a593Smuzhiyun ret = devm_led_classdev_register(dev, &leds[i].led_cdev);
116*4882a593Smuzhiyun if (ret)
117*4882a593Smuzhiyun return ret;
118*4882a593Smuzhiyun }
119*4882a593Smuzhiyun
120*4882a593Smuzhiyun return 0;
121*4882a593Smuzhiyun }
122*4882a593Smuzhiyun
123*4882a593Smuzhiyun static struct platform_driver ariel_led_driver = {
124*4882a593Smuzhiyun .probe = ariel_led_probe,
125*4882a593Smuzhiyun .driver = {
126*4882a593Smuzhiyun .name = "dell-wyse-ariel-led",
127*4882a593Smuzhiyun },
128*4882a593Smuzhiyun };
129*4882a593Smuzhiyun module_platform_driver(ariel_led_driver);
130*4882a593Smuzhiyun
131*4882a593Smuzhiyun MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
132*4882a593Smuzhiyun MODULE_DESCRIPTION("Dell Wyse 3020 Status LEDs Driver");
133*4882a593Smuzhiyun MODULE_LICENSE("Dual BSD/GPL");
134