xref: /openbmc/linux/drivers/leds/leds-da9052.c (revision 6d99a79c)
1 /*
2  * LED Driver for Dialog DA9052 PMICs.
3  *
4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
5  *
6  * Author: David Dajun Chen <dchen@diasemi.com>
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  *
13  */
14 
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/platform_device.h>
18 #include <linux/leds.h>
19 #include <linux/slab.h>
20 
21 #include <linux/mfd/da9052/reg.h>
22 #include <linux/mfd/da9052/da9052.h>
23 #include <linux/mfd/da9052/pdata.h>
24 
25 #define DA9052_OPENDRAIN_OUTPUT	2
26 #define DA9052_SET_HIGH_LVL_OUTPUT	(1 << 3)
27 #define DA9052_MASK_UPPER_NIBBLE	0xF0
28 #define DA9052_MASK_LOWER_NIBBLE	0x0F
29 #define DA9052_NIBBLE_SHIFT		4
30 #define DA9052_MAX_BRIGHTNESS		0x5f
31 
32 struct da9052_led {
33 	struct led_classdev cdev;
34 	struct da9052 *da9052;
35 	unsigned char led_index;
36 	unsigned char id;
37 };
38 
39 static unsigned char led_reg[] = {
40 	DA9052_LED_CONT_4_REG,
41 	DA9052_LED_CONT_5_REG,
42 };
43 
44 static int da9052_set_led_brightness(struct da9052_led *led,
45 				     enum led_brightness brightness)
46 {
47 	u8 val;
48 	int error;
49 
50 	val = (brightness & 0x7f) | DA9052_LED_CONT_DIM;
51 
52 	error = da9052_reg_write(led->da9052, led_reg[led->led_index], val);
53 	if (error < 0)
54 		dev_err(led->da9052->dev, "Failed to set led brightness, %d\n",
55 			error);
56 	return error;
57 }
58 
59 static int da9052_led_set(struct led_classdev *led_cdev,
60 			   enum led_brightness value)
61 {
62 	struct da9052_led *led =
63 			container_of(led_cdev, struct da9052_led, cdev);
64 
65 	return da9052_set_led_brightness(led, value);
66 }
67 
68 static int da9052_configure_leds(struct da9052 *da9052)
69 {
70 	int error;
71 	unsigned char register_value = DA9052_OPENDRAIN_OUTPUT
72 				       | DA9052_SET_HIGH_LVL_OUTPUT;
73 
74 	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
75 				  DA9052_MASK_LOWER_NIBBLE,
76 				  register_value);
77 
78 	if (error < 0) {
79 		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
80 			error);
81 		return error;
82 	}
83 
84 	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
85 				  DA9052_MASK_UPPER_NIBBLE,
86 				  register_value << DA9052_NIBBLE_SHIFT);
87 	if (error < 0)
88 		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
89 			error);
90 
91 	return error;
92 }
93 
94 static int da9052_led_probe(struct platform_device *pdev)
95 {
96 	struct da9052_pdata *pdata;
97 	struct da9052 *da9052;
98 	struct led_platform_data *pled;
99 	struct da9052_led *led = NULL;
100 	int error = -ENODEV;
101 	int i;
102 
103 	da9052 = dev_get_drvdata(pdev->dev.parent);
104 	pdata = dev_get_platdata(da9052->dev);
105 	if (pdata == NULL) {
106 		dev_err(&pdev->dev, "No platform data\n");
107 		goto err;
108 	}
109 
110 	pled = pdata->pled;
111 	if (pled == NULL) {
112 		dev_err(&pdev->dev, "No platform data for LED\n");
113 		goto err;
114 	}
115 
116 	led = devm_kcalloc(&pdev->dev,
117 			   pled->num_leds, sizeof(struct da9052_led),
118 			   GFP_KERNEL);
119 	if (!led) {
120 		error = -ENOMEM;
121 		goto err;
122 	}
123 
124 	for (i = 0; i < pled->num_leds; i++) {
125 		led[i].cdev.name = pled->leds[i].name;
126 		led[i].cdev.brightness_set_blocking = da9052_led_set;
127 		led[i].cdev.brightness = LED_OFF;
128 		led[i].cdev.max_brightness = DA9052_MAX_BRIGHTNESS;
129 		led[i].led_index = pled->leds[i].flags;
130 		led[i].da9052 = dev_get_drvdata(pdev->dev.parent);
131 
132 		error = led_classdev_register(pdev->dev.parent, &led[i].cdev);
133 		if (error) {
134 			dev_err(&pdev->dev, "Failed to register led %d\n",
135 				led[i].led_index);
136 			goto err_register;
137 		}
138 
139 		error = da9052_set_led_brightness(&led[i],
140 						  led[i].cdev.brightness);
141 		if (error) {
142 			dev_err(&pdev->dev, "Unable to init led %d\n",
143 				led[i].led_index);
144 			continue;
145 		}
146 	}
147 	error = da9052_configure_leds(led->da9052);
148 	if (error) {
149 		dev_err(&pdev->dev, "Failed to configure GPIO LED%d\n", error);
150 		goto err_register;
151 	}
152 
153 	platform_set_drvdata(pdev, led);
154 
155 	return 0;
156 
157 err_register:
158 	for (i = i - 1; i >= 0; i--)
159 		led_classdev_unregister(&led[i].cdev);
160 err:
161 	return error;
162 }
163 
164 static int da9052_led_remove(struct platform_device *pdev)
165 {
166 	struct da9052_led *led = platform_get_drvdata(pdev);
167 	struct da9052_pdata *pdata;
168 	struct da9052 *da9052;
169 	struct led_platform_data *pled;
170 	int i;
171 
172 	da9052 = dev_get_drvdata(pdev->dev.parent);
173 	pdata = dev_get_platdata(da9052->dev);
174 	pled = pdata->pled;
175 
176 	for (i = 0; i < pled->num_leds; i++) {
177 		da9052_set_led_brightness(&led[i], LED_OFF);
178 		led_classdev_unregister(&led[i].cdev);
179 	}
180 
181 	return 0;
182 }
183 
184 static struct platform_driver da9052_led_driver = {
185 	.driver		= {
186 		.name	= "da9052-leds",
187 	},
188 	.probe		= da9052_led_probe,
189 	.remove		= da9052_led_remove,
190 };
191 
192 module_platform_driver(da9052_led_driver);
193 
194 MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>");
195 MODULE_DESCRIPTION("LED driver for Dialog DA9052 PMIC");
196 MODULE_LICENSE("GPL");
197