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git.odroid.com / yocto / kernel / common / c942fddf8793b2013be8c901b47d0a8dc02bf99f / . / drivers / leds / leds-max77650.c
blob: 6b74ce9cac12118be314e9f6564c76f1bb36b62d [file] [log] [blame]
Bartosz Golaszewski5be102e2019-04-23 11:04:49 +0200[diff] [blame]1// SPDX-License-Identifier: GPL-2.0
2//
3// Copyright (C) 2018 BayLibre SAS
4// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
5//
6// LED driver for MAXIM 77650/77651 charger/power-supply.
7
8#include <linux/i2c.h>
9#include <linux/leds.h>
10#include <linux/mfd/max77650.h>
11#include <linux/module.h>
12#include <linux/platform_device.h>
13#include <linux/regmap.h>
14
15#define MAX77650_LED_NUM_LEDS 3
16
17#define MAX77650_LED_A_BASE 0x40
18#define MAX77650_LED_B_BASE 0x43
19
20#define MAX77650_LED_BR_MASK GENMASK(4, 0)
21#define MAX77650_LED_EN_MASK GENMASK(7, 6)
22
23#define MAX77650_LED_MAX_BRIGHTNESS MAX77650_LED_BR_MASK
24
25/* Enable EN_LED_MSTR. */
26#define MAX77650_LED_TOP_DEFAULT BIT(0)
27
28#define MAX77650_LED_ENABLE GENMASK(7, 6)
29#define MAX77650_LED_DISABLE 0x00
30
31#define MAX77650_LED_A_DEFAULT MAX77650_LED_DISABLE
32/* 100% on duty */
33#define MAX77650_LED_B_DEFAULT GENMASK(3, 0)
34
35struct max77650_led {
36 struct led_classdev cdev;
37 struct regmap *map;
38 unsigned int regA;
39 unsigned int regB;
40};
41
42static struct max77650_led *max77650_to_led(struct led_classdev *cdev)
43{
44 return container_of(cdev, struct max77650_led, cdev);
45}
46
47static int max77650_led_brightness_set(struct led_classdev *cdev,
48 enum led_brightness brightness)
49{
50 struct max77650_led *led = max77650_to_led(cdev);
51 int val, mask;
52
53 mask = MAX77650_LED_BR_MASK | MAX77650_LED_EN_MASK;
54
55 if (brightness == LED_OFF)
56 val = MAX77650_LED_DISABLE;
57 else
58 val = MAX77650_LED_ENABLE | brightness;
59
60 return regmap_update_bits(led->map, led->regA, mask, val);
61}
62
63static int max77650_led_probe(struct platform_device *pdev)
64{
65 struct device_node *of_node, *child;
66 struct max77650_led *leds, *led;
67 struct device *parent;
68 struct device *dev;
69 struct regmap *map;
70 const char *label;
71 int rv, num_leds;
72 u32 reg;
73
74 dev = &pdev->dev;
75 parent = dev->parent;
76 of_node = dev->of_node;
77
78 if (!of_node)
79 return -ENODEV;
80
81 leds = devm_kcalloc(dev, sizeof(*leds),
82 MAX77650_LED_NUM_LEDS, GFP_KERNEL);
83 if (!leds)
84 return -ENOMEM;
85
86 map = dev_get_regmap(dev->parent, NULL);
87 if (!map)
88 return -ENODEV;
89
90 num_leds = of_get_child_count(of_node);
91 if (!num_leds || num_leds > MAX77650_LED_NUM_LEDS)
92 return -ENODEV;
93
94 for_each_child_of_node(of_node, child) {
95 rv = of_property_read_u32(child, "reg", &reg);
96 if (rv || reg >= MAX77650_LED_NUM_LEDS)
97 return -EINVAL;
98
99 led = &leds[reg];
100 led->map = map;
101 led->regA = MAX77650_LED_A_BASE + reg;
102 led->regB = MAX77650_LED_B_BASE + reg;
103 led->cdev.brightness_set_blocking = max77650_led_brightness_set;
104 led->cdev.max_brightness = MAX77650_LED_MAX_BRIGHTNESS;
105
106 label = of_get_property(child, "label", NULL);
107 if (!label) {
108 led->cdev.name = "max77650::";
109 } else {
110 led->cdev.name = devm_kasprintf(dev, GFP_KERNEL,
111 "max77650:%s", label);
112 if (!led->cdev.name)
113 return -ENOMEM;
114 }
115
116 of_property_read_string(child, "linux,default-trigger",
117 &led->cdev.default_trigger);
118
119 rv = devm_of_led_classdev_register(dev, child, &led->cdev);
120 if (rv)
121 return rv;
122
123 rv = regmap_write(map, led->regA, MAX77650_LED_A_DEFAULT);
124 if (rv)
125 return rv;
126
127 rv = regmap_write(map, led->regB, MAX77650_LED_B_DEFAULT);
128 if (rv)
129 return rv;
130 }
131
132 return regmap_write(map,
133 MAX77650_REG_CNFG_LED_TOP,
134 MAX77650_LED_TOP_DEFAULT);
135}
136
137static struct platform_driver max77650_led_driver = {
138 .driver = {
139 .name = "max77650-led",
140 },
141 .probe = max77650_led_probe,
142};
143module_platform_driver(max77650_led_driver);
144
145MODULE_DESCRIPTION("MAXIM 77650/77651 LED driver");
146MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
147MODULE_LICENSE("GPL v2");