xref: /openbmc/linux/drivers/leds/leds-pm8058.c (revision d3964221)
1 /* Copyright (c) 2010, 2011, 2016 The Linux Foundation. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 and
5  * only version 2 as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  */
12 #include <linux/leds.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm.h>
18 #include <linux/regmap.h>
19 
20 #define PM8058_LED_TYPE_COMMON	0x00
21 #define PM8058_LED_TYPE_KEYPAD	0x01
22 #define PM8058_LED_TYPE_FLASH	0x02
23 
24 #define PM8058_LED_TYPE_COMMON_MASK	0xf8
25 #define PM8058_LED_TYPE_KEYPAD_MASK	0xf0
26 #define PM8058_LED_TYPE_COMMON_SHIFT	3
27 #define PM8058_LED_TYPE_KEYPAD_SHIFT	4
28 
29 struct pm8058_led {
30 	struct regmap *map;
31 	u32 reg;
32 	u32 ledtype;
33 	struct led_classdev cdev;
34 };
35 
36 static void pm8058_led_set(struct led_classdev *cled,
37 	enum led_brightness value)
38 {
39 	struct pm8058_led *led;
40 	int ret = 0;
41 	unsigned int mask = 0;
42 	unsigned int val = 0;
43 
44 	led = container_of(cled, struct pm8058_led, cdev);
45 	switch (led->ledtype) {
46 	case PM8058_LED_TYPE_COMMON:
47 		mask = PM8058_LED_TYPE_COMMON_MASK;
48 		val = value << PM8058_LED_TYPE_COMMON_SHIFT;
49 		break;
50 	case PM8058_LED_TYPE_KEYPAD:
51 	case PM8058_LED_TYPE_FLASH:
52 		mask = PM8058_LED_TYPE_KEYPAD_MASK;
53 		val = value << PM8058_LED_TYPE_KEYPAD_SHIFT;
54 		break;
55 	default:
56 		break;
57 	}
58 
59 	ret = regmap_update_bits(led->map, led->reg, mask, val);
60 	if (ret)
61 		pr_err("Failed to set LED brightness\n");
62 }
63 
64 static enum led_brightness pm8058_led_get(struct led_classdev *cled)
65 {
66 	struct pm8058_led *led;
67 	int ret;
68 	unsigned int val;
69 
70 	led = container_of(cled, struct pm8058_led, cdev);
71 
72 	ret = regmap_read(led->map, led->reg, &val);
73 	if (ret) {
74 		pr_err("Failed to get LED brightness\n");
75 		return LED_OFF;
76 	}
77 
78 	switch (led->ledtype) {
79 	case PM8058_LED_TYPE_COMMON:
80 		val &= PM8058_LED_TYPE_COMMON_MASK;
81 		val >>= PM8058_LED_TYPE_COMMON_SHIFT;
82 		break;
83 	case PM8058_LED_TYPE_KEYPAD:
84 	case PM8058_LED_TYPE_FLASH:
85 		val &= PM8058_LED_TYPE_KEYPAD_MASK;
86 		val >>= PM8058_LED_TYPE_KEYPAD_SHIFT;
87 		break;
88 	default:
89 		val = LED_OFF;
90 		break;
91 	}
92 
93 	return val;
94 }
95 
96 static int pm8058_led_probe(struct platform_device *pdev)
97 {
98 	struct pm8058_led *led;
99 	struct device_node *np = pdev->dev.of_node;
100 	int ret;
101 	struct regmap *map;
102 	const char *state;
103 	enum led_brightness maxbright;
104 
105 	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
106 	if (!led)
107 		return -ENOMEM;
108 
109 	led->ledtype = (u32)of_device_get_match_data(&pdev->dev);
110 
111 	map = dev_get_regmap(pdev->dev.parent, NULL);
112 	if (!map) {
113 		dev_err(&pdev->dev, "Parent regmap unavailable.\n");
114 		return -ENXIO;
115 	}
116 	led->map = map;
117 
118 	ret = of_property_read_u32(np, "reg", &led->reg);
119 	if (ret) {
120 		dev_err(&pdev->dev, "no register offset specified\n");
121 		return -EINVAL;
122 	}
123 
124 	/* Use label else node name */
125 	led->cdev.name = of_get_property(np, "label", NULL) ? : np->name;
126 	led->cdev.default_trigger =
127 		of_get_property(np, "linux,default-trigger", NULL);
128 	led->cdev.brightness_set = pm8058_led_set;
129 	led->cdev.brightness_get = pm8058_led_get;
130 	if (led->ledtype == PM8058_LED_TYPE_COMMON)
131 		maxbright = 31; /* 5 bits */
132 	else
133 		maxbright = 15; /* 4 bits */
134 	led->cdev.max_brightness = maxbright;
135 
136 	state = of_get_property(np, "default-state", NULL);
137 	if (state) {
138 		if (!strcmp(state, "keep")) {
139 			led->cdev.brightness = pm8058_led_get(&led->cdev);
140 		} else if (!strcmp(state, "on")) {
141 			led->cdev.brightness = maxbright;
142 			pm8058_led_set(&led->cdev, maxbright);
143 		} else {
144 			led->cdev.brightness = LED_OFF;
145 			pm8058_led_set(&led->cdev, LED_OFF);
146 		}
147 	}
148 
149 	if (led->ledtype == PM8058_LED_TYPE_KEYPAD ||
150 	    led->ledtype == PM8058_LED_TYPE_FLASH)
151 		led->cdev.flags	= LED_CORE_SUSPENDRESUME;
152 
153 	ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
154 	if (ret) {
155 		dev_err(&pdev->dev, "unable to register led \"%s\"\n",
156 			led->cdev.name);
157 		return ret;
158 	}
159 
160 	return 0;
161 }
162 
163 static const struct of_device_id pm8058_leds_id_table[] = {
164 	{
165 		.compatible = "qcom,pm8058-led",
166 		.data = (void *)PM8058_LED_TYPE_COMMON
167 	},
168 	{
169 		.compatible = "qcom,pm8058-keypad-led",
170 		.data = (void *)PM8058_LED_TYPE_KEYPAD
171 	},
172 	{
173 		.compatible = "qcom,pm8058-flash-led",
174 		.data = (void *)PM8058_LED_TYPE_FLASH
175 	},
176 	{ },
177 };
178 MODULE_DEVICE_TABLE(of, pm8058_leds_id_table);
179 
180 static struct platform_driver pm8058_led_driver = {
181 	.probe		= pm8058_led_probe,
182 	.driver		= {
183 		.name	= "pm8058-leds",
184 		.of_match_table = pm8058_leds_id_table,
185 	},
186 };
187 module_platform_driver(pm8058_led_driver);
188 
189 MODULE_DESCRIPTION("PM8058 LEDs driver");
190 MODULE_LICENSE("GPL v2");
191 MODULE_ALIAS("platform:pm8058-leds");
192