xref: /openbmc/linux/drivers/leds/leds-da9052.c (revision b6bec26c)
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/init.h>
18 #include <linux/platform_device.h>
19 #include <linux/leds.h>
20 #include <linux/workqueue.h>
21 #include <linux/slab.h>
22 
23 #include <linux/mfd/da9052/reg.h>
24 #include <linux/mfd/da9052/da9052.h>
25 #include <linux/mfd/da9052/pdata.h>
26 
27 #define DA9052_OPENDRAIN_OUTPUT	2
28 #define DA9052_SET_HIGH_LVL_OUTPUT	(1 << 3)
29 #define DA9052_MASK_UPPER_NIBBLE	0xF0
30 #define DA9052_MASK_LOWER_NIBBLE	0x0F
31 #define DA9052_NIBBLE_SHIFT		4
32 #define DA9052_MAX_BRIGHTNESS		0x5f
33 
34 struct da9052_led {
35 	struct led_classdev cdev;
36 	struct work_struct work;
37 	struct da9052 *da9052;
38 	unsigned char led_index;
39 	unsigned char id;
40 	int brightness;
41 };
42 
43 static unsigned char led_reg[] = {
44 	DA9052_LED_CONT_4_REG,
45 	DA9052_LED_CONT_5_REG,
46 };
47 
48 static int da9052_set_led_brightness(struct da9052_led *led)
49 {
50 	u8 val;
51 	int error;
52 
53 	val = (led->brightness & 0x7f) | DA9052_LED_CONT_DIM;
54 
55 	error = da9052_reg_write(led->da9052, led_reg[led->led_index], val);
56 	if (error < 0)
57 		dev_err(led->da9052->dev, "Failed to set led brightness, %d\n",
58 			error);
59 	return error;
60 }
61 
62 static void da9052_led_work(struct work_struct *work)
63 {
64 	struct da9052_led *led = container_of(work, struct da9052_led, work);
65 
66 	da9052_set_led_brightness(led);
67 }
68 
69 static void da9052_led_set(struct led_classdev *led_cdev,
70 			   enum led_brightness value)
71 {
72 	struct da9052_led *led;
73 
74 	led = container_of(led_cdev, struct da9052_led, cdev);
75 	led->brightness = value;
76 	schedule_work(&led->work);
77 }
78 
79 static int da9052_configure_leds(struct da9052 *da9052)
80 {
81 	int error;
82 	unsigned char register_value = DA9052_OPENDRAIN_OUTPUT
83 				       | DA9052_SET_HIGH_LVL_OUTPUT;
84 
85 	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
86 				  DA9052_MASK_LOWER_NIBBLE,
87 				  register_value);
88 
89 	if (error < 0) {
90 		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
91 			error);
92 		return error;
93 	}
94 
95 	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
96 				  DA9052_MASK_UPPER_NIBBLE,
97 				  register_value << DA9052_NIBBLE_SHIFT);
98 	if (error < 0)
99 		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
100 			error);
101 
102 	return error;
103 }
104 
105 static int da9052_led_probe(struct platform_device *pdev)
106 {
107 	struct da9052_pdata *pdata;
108 	struct da9052 *da9052;
109 	struct led_platform_data *pled;
110 	struct da9052_led *led = NULL;
111 	int error = -ENODEV;
112 	int i;
113 
114 	da9052 = dev_get_drvdata(pdev->dev.parent);
115 	pdata = da9052->dev->platform_data;
116 	if (pdata == NULL) {
117 		dev_err(&pdev->dev, "No platform data\n");
118 		goto err;
119 	}
120 
121 	pled = pdata->pled;
122 	if (pled == NULL) {
123 		dev_err(&pdev->dev, "No platform data for LED\n");
124 		goto err;
125 	}
126 
127 	led = devm_kzalloc(&pdev->dev,
128 			   sizeof(struct da9052_led) * pled->num_leds,
129 			   GFP_KERNEL);
130 	if (led == NULL) {
131 		dev_err(&pdev->dev, "Failed to alloc memory\n");
132 		error = -ENOMEM;
133 		goto err;
134 	}
135 
136 	for (i = 0; i < pled->num_leds; i++) {
137 		led[i].cdev.name = pled->leds[i].name;
138 		led[i].cdev.brightness_set = da9052_led_set;
139 		led[i].cdev.brightness = LED_OFF;
140 		led[i].cdev.max_brightness = DA9052_MAX_BRIGHTNESS;
141 		led[i].brightness = LED_OFF;
142 		led[i].led_index = pled->leds[i].flags;
143 		led[i].da9052 = dev_get_drvdata(pdev->dev.parent);
144 		INIT_WORK(&led[i].work, da9052_led_work);
145 
146 		error = led_classdev_register(pdev->dev.parent, &led[i].cdev);
147 		if (error) {
148 			dev_err(&pdev->dev, "Failed to register led %d\n",
149 				led[i].led_index);
150 			goto err_register;
151 		}
152 
153 		error = da9052_set_led_brightness(&led[i]);
154 		if (error) {
155 			dev_err(&pdev->dev, "Unable to init led %d\n",
156 				led[i].led_index);
157 			continue;
158 		}
159 	}
160 	error = da9052_configure_leds(led->da9052);
161 	if (error) {
162 		dev_err(&pdev->dev, "Failed to configure GPIO LED%d\n", error);
163 		goto err_register;
164 	}
165 
166 	platform_set_drvdata(pdev, led);
167 
168 	return 0;
169 
170 err_register:
171 	for (i = i - 1; i >= 0; i--) {
172 		led_classdev_unregister(&led[i].cdev);
173 		cancel_work_sync(&led[i].work);
174 	}
175 err:
176 	return error;
177 }
178 
179 static int da9052_led_remove(struct platform_device *pdev)
180 {
181 	struct da9052_led *led = platform_get_drvdata(pdev);
182 	struct da9052_pdata *pdata;
183 	struct da9052 *da9052;
184 	struct led_platform_data *pled;
185 	int i;
186 
187 	da9052 = dev_get_drvdata(pdev->dev.parent);
188 	pdata = da9052->dev->platform_data;
189 	pled = pdata->pled;
190 
191 	for (i = 0; i < pled->num_leds; i++) {
192 		led[i].brightness = 0;
193 		da9052_set_led_brightness(&led[i]);
194 		led_classdev_unregister(&led[i].cdev);
195 		cancel_work_sync(&led[i].work);
196 	}
197 
198 	return 0;
199 }
200 
201 static struct platform_driver da9052_led_driver = {
202 	.driver		= {
203 		.name	= "da9052-leds",
204 		.owner	= THIS_MODULE,
205 	},
206 	.probe		= da9052_led_probe,
207 	.remove		= da9052_led_remove,
208 };
209 
210 module_platform_driver(da9052_led_driver);
211 
212 MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>");
213 MODULE_DESCRIPTION("LED driver for Dialog DA9052 PMIC");
214 MODULE_LICENSE("GPL");
215