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/platform_device.h> |
11 | #include <linux/regmap.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(map: led->ec_ram, reg: led->ec_index, val: &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(map: led->ec_ram, reg: led->ec_index, val: EC_LED_OFF); |
55 | else |
56 | regmap_write(map: led->ec_ram, reg: led->ec_index, val: 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(map: led->ec_ram, reg: led->ec_index, val: EC_LED_OFF); |
69 | } else if (*delay_off == 0) { |
70 | regmap_write(map: led->ec_ram, reg: led->ec_index, val: EC_LED_STILL); |
71 | } else { |
72 | *delay_on = 500; |
73 | *delay_off = 500; |
74 | regmap_write(map: led->ec_ram, reg: led->ec_index, val: 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: dev->parent, name: "ec_ram" ); |
91 | if (!ec_ram) |
92 | return -ENODEV; |
93 | |
94 | leds = devm_kcalloc(dev, NLEDS, size: 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(parent: dev, led_cdev: &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" ); |
134 | |