Merge tag 'gvt-next-fixes-2021-04-21' of https://github.com/intel/gvt-linux into...
[platform/kernel/linux-rpi.git] / drivers / leds / leds-ariel.c
1 // SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0-or-later
2 /*
3  * Dell Wyse 3020 a.k.a. "Ariel" Embedded Controller LED Driver
4  *
5  * Copyright (C) 2020 Lubomir Rintel
6  */
7
8 #include <linux/module.h>
9 #include <linux/leds.h>
10 #include <linux/regmap.h>
11 #include <linux/of_platform.h>
12
13 enum ec_index {
14         EC_BLUE_LED     = 0x01,
15         EC_AMBER_LED    = 0x02,
16         EC_GREEN_LED    = 0x03,
17 };
18
19 enum {
20         EC_LED_OFF      = 0x00,
21         EC_LED_STILL    = 0x01,
22         EC_LED_FADE     = 0x02,
23         EC_LED_BLINK    = 0x03,
24 };
25
26 struct 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
34 static 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         else
45                 return LED_OFF;
46 }
47
48 static 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         else
56                 regmap_write(led->ec_ram, led->ec_index, EC_LED_STILL);
57 }
58
59 static 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 3
81
82 static 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
123 static struct platform_driver ariel_led_driver = {
124         .probe = ariel_led_probe,
125         .driver = {
126                 .name = "dell-wyse-ariel-led",
127         },
128 };
129 module_platform_driver(ariel_led_driver);
130
131 MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
132 MODULE_DESCRIPTION("Dell Wyse 3020 Status LEDs Driver");
133 MODULE_LICENSE("Dual BSD/GPL");