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1/*
2 * linux/drivers/leds-pwm.c
3 *
4 * simple PWM based LED control
5 *
6 * Copyright 2009 Luotao Fu @ Pengutronix (l.fu@pengutronix.de)
7 *
8 * based on leds-gpio.c by Raphael Assenat <raph@8d.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
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/fb.h>
20#include <linux/leds.h>
21#include <linux/err.h>
22#include <linux/pwm.h>
23#include <linux/leds_pwm.h>
24#include <linux/slab.h>
25
26struct led_pwm_data {
27 struct led_classdev cdev;
28 struct pwm_device *pwm;
29 unsigned int active_low;
30 unsigned int period;
31};
32
33static void led_pwm_set(struct led_classdev *led_cdev,
34 enum led_brightness brightness)
35{
36 struct led_pwm_data *led_dat =
37 container_of(led_cdev, struct led_pwm_data, cdev);
38 unsigned int max = led_dat->cdev.max_brightness;
39 unsigned int period = led_dat->period;
40
41 if (brightness == 0) {
42 pwm_config(led_dat->pwm, 0, period);
43 pwm_disable(led_dat->pwm);
44 } else {
45 pwm_config(led_dat->pwm, brightness * period / max, period);
46 pwm_enable(led_dat->pwm);
47 }
48}
49
50static int led_pwm_probe(struct platform_device *pdev)
51{
52 struct led_pwm_platform_data *pdata = pdev->dev.platform_data;
53 struct led_pwm *cur_led;
54 struct led_pwm_data *leds_data, *led_dat;
55 int i, ret = 0;
56
57 if (!pdata)
58 return -EBUSY;
59
60 leds_data = kzalloc(sizeof(struct led_pwm_data) * pdata->num_leds,
61 GFP_KERNEL);
62 if (!leds_data)
63 return -ENOMEM;
64
65 for (i = 0; i < pdata->num_leds; i++) {
66 cur_led = &pdata->leds[i];
67 led_dat = &leds_data[i];
68
69 led_dat->pwm = pwm_request(cur_led->pwm_id,
70 cur_led->name);
71 if (IS_ERR(led_dat->pwm)) {
72 ret = PTR_ERR(led_dat->pwm);
73 dev_err(&pdev->dev, "unable to request PWM %d\n",
74 cur_led->pwm_id);
75 goto err;
76 }
77
78 led_dat->cdev.name = cur_led->name;
79 led_dat->cdev.default_trigger = cur_led->default_trigger;
80 led_dat->active_low = cur_led->active_low;
81 led_dat->period = cur_led->pwm_period_ns;
82 led_dat->cdev.brightness_set = led_pwm_set;
83 led_dat->cdev.brightness = LED_OFF;
84 led_dat->cdev.max_brightness = cur_led->max_brightness;
85 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
86
87 ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
88 if (ret < 0) {
89 pwm_free(led_dat->pwm);
90 goto err;
91 }
92 }
93
94 platform_set_drvdata(pdev, leds_data);
95
96 return 0;
97
98err:
99 if (i > 0) {
100 for (i = i - 1; i >= 0; i--) {
101 led_classdev_unregister(&leds_data[i].cdev);
102 pwm_free(leds_data[i].pwm);
103 }
104 }
105
106 kfree(leds_data);
107
108 return ret;
109}
110
111static int __devexit led_pwm_remove(struct platform_device *pdev)
112{
113 int i;
114 struct led_pwm_platform_data *pdata = pdev->dev.platform_data;
115 struct led_pwm_data *leds_data;
116
117 leds_data = platform_get_drvdata(pdev);
118
119 for (i = 0; i < pdata->num_leds; i++) {
120 led_classdev_unregister(&leds_data[i].cdev);
121 pwm_free(leds_data[i].pwm);
122 }
123
124 kfree(leds_data);
125
126 return 0;
127}
128
129static struct platform_driver led_pwm_driver = {
130 .probe = led_pwm_probe,
131 .remove = __devexit_p(led_pwm_remove),
132 .driver = {
133 .name = "leds_pwm",
134 .owner = THIS_MODULE,
135 },
136};
137
138module_platform_driver(led_pwm_driver);
139
140MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
141MODULE_DESCRIPTION("PWM LED driver for PXA");
142MODULE_LICENSE("GPL");
143MODULE_ALIAS("platform:leds-pwm");
1/*
2 * linux/drivers/leds-pwm.c
3 *
4 * simple PWM based LED control
5 *
6 * Copyright 2009 Luotao Fu @ Pengutronix (l.fu@pengutronix.de)
7 *
8 * based on leds-gpio.c by Raphael Assenat <raph@8d.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
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/fb.h>
20#include <linux/leds.h>
21#include <linux/err.h>
22#include <linux/pwm.h>
23#include <linux/leds_pwm.h>
24#include <linux/slab.h>
25
26struct led_pwm_data {
27 struct led_classdev cdev;
28 struct pwm_device *pwm;
29 unsigned int active_low;
30 unsigned int period;
31};
32
33static void led_pwm_set(struct led_classdev *led_cdev,
34 enum led_brightness brightness)
35{
36 struct led_pwm_data *led_dat =
37 container_of(led_cdev, struct led_pwm_data, cdev);
38 unsigned int max = led_dat->cdev.max_brightness;
39 unsigned int period = led_dat->period;
40
41 if (brightness == 0) {
42 pwm_config(led_dat->pwm, 0, period);
43 pwm_disable(led_dat->pwm);
44 } else {
45 pwm_config(led_dat->pwm, brightness * period / max, period);
46 pwm_enable(led_dat->pwm);
47 }
48}
49
50static int led_pwm_probe(struct platform_device *pdev)
51{
52 struct led_pwm_platform_data *pdata = pdev->dev.platform_data;
53 struct led_pwm *cur_led;
54 struct led_pwm_data *leds_data, *led_dat;
55 int i, ret = 0;
56
57 if (!pdata)
58 return -EBUSY;
59
60 leds_data = kzalloc(sizeof(struct led_pwm_data) * pdata->num_leds,
61 GFP_KERNEL);
62 if (!leds_data)
63 return -ENOMEM;
64
65 for (i = 0; i < pdata->num_leds; i++) {
66 cur_led = &pdata->leds[i];
67 led_dat = &leds_data[i];
68
69 led_dat->pwm = pwm_request(cur_led->pwm_id,
70 cur_led->name);
71 if (IS_ERR(led_dat->pwm)) {
72 ret = PTR_ERR(led_dat->pwm);
73 dev_err(&pdev->dev, "unable to request PWM %d\n",
74 cur_led->pwm_id);
75 goto err;
76 }
77
78 led_dat->cdev.name = cur_led->name;
79 led_dat->cdev.default_trigger = cur_led->default_trigger;
80 led_dat->active_low = cur_led->active_low;
81 led_dat->period = cur_led->pwm_period_ns;
82 led_dat->cdev.brightness_set = led_pwm_set;
83 led_dat->cdev.brightness = LED_OFF;
84 led_dat->cdev.max_brightness = cur_led->max_brightness;
85 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
86
87 ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
88 if (ret < 0) {
89 pwm_free(led_dat->pwm);
90 goto err;
91 }
92 }
93
94 platform_set_drvdata(pdev, leds_data);
95
96 return 0;
97
98err:
99 if (i > 0) {
100 for (i = i - 1; i >= 0; i--) {
101 led_classdev_unregister(&leds_data[i].cdev);
102 pwm_free(leds_data[i].pwm);
103 }
104 }
105
106 kfree(leds_data);
107
108 return ret;
109}
110
111static int __devexit led_pwm_remove(struct platform_device *pdev)
112{
113 int i;
114 struct led_pwm_platform_data *pdata = pdev->dev.platform_data;
115 struct led_pwm_data *leds_data;
116
117 leds_data = platform_get_drvdata(pdev);
118
119 for (i = 0; i < pdata->num_leds; i++) {
120 led_classdev_unregister(&leds_data[i].cdev);
121 pwm_free(leds_data[i].pwm);
122 }
123
124 kfree(leds_data);
125
126 return 0;
127}
128
129static struct platform_driver led_pwm_driver = {
130 .probe = led_pwm_probe,
131 .remove = __devexit_p(led_pwm_remove),
132 .driver = {
133 .name = "leds_pwm",
134 .owner = THIS_MODULE,
135 },
136};
137
138static int __init led_pwm_init(void)
139{
140 return platform_driver_register(&led_pwm_driver);
141}
142
143static void __exit led_pwm_exit(void)
144{
145 platform_driver_unregister(&led_pwm_driver);
146}
147
148module_init(led_pwm_init);
149module_exit(led_pwm_exit);
150
151MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
152MODULE_DESCRIPTION("PWM LED driver for PXA");
153MODULE_LICENSE("GPL");
154MODULE_ALIAS("platform:leds-pwm");