libceph: move r_reply_op_{len,result} into struct ceph_osd_req_op
[linux-2.6-block.git] / drivers / leds / leds-pwm.c
CommitLineData
41c42ff5
LF
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>
41c42ff5 17#include <linux/platform_device.h>
08541cbc 18#include <linux/of_platform.h>
41c42ff5
LF
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>
5a0e3ad6 24#include <linux/slab.h>
41c42ff5
LF
25
26struct led_pwm_data {
27 struct led_classdev cdev;
28 struct pwm_device *pwm;
dcba9105 29 unsigned int active_low;
41c42ff5 30 unsigned int period;
c971ff18
FV
31 int duty;
32 bool can_sleep;
41c42ff5
LF
33};
34
0f86815a
PU
35struct led_pwm_priv {
36 int num_leds;
37 struct led_pwm_data leds[0];
38};
39
c971ff18
FV
40static void __led_pwm_set(struct led_pwm_data *led_dat)
41{
42 int new_duty = led_dat->duty;
43
44 pwm_config(led_dat->pwm, new_duty, led_dat->period);
45
46 if (new_duty == 0)
47 pwm_disable(led_dat->pwm);
48 else
49 pwm_enable(led_dat->pwm);
50}
51
41c42ff5
LF
52static void led_pwm_set(struct led_classdev *led_cdev,
53 enum led_brightness brightness)
54{
55 struct led_pwm_data *led_dat =
56 container_of(led_cdev, struct led_pwm_data, cdev);
e4590620 57 unsigned int max = led_dat->cdev.max_brightness;
fc1aee03 58 unsigned long long duty = led_dat->period;
41c42ff5 59
fc1aee03
XL
60 duty *= brightness;
61 do_div(duty, max);
d19a8a70
RK
62
63 if (led_dat->active_low)
64 duty = led_dat->period - duty;
65
fc1aee03 66 led_dat->duty = duty;
c971ff18 67
9aa07625
JA
68 __led_pwm_set(led_dat);
69}
70
71static int led_pwm_set_blocking(struct led_classdev *led_cdev,
72 enum led_brightness brightness)
73{
74 led_pwm_set(led_cdev, brightness);
75 return 0;
41c42ff5
LF
76}
77
0f86815a
PU
78static inline size_t sizeof_pwm_leds_priv(int num_leds)
79{
80 return sizeof(struct led_pwm_priv) +
81 (sizeof(struct led_pwm_data) * num_leds);
82}
83
39236901
RK
84static void led_pwm_cleanup(struct led_pwm_priv *priv)
85{
9aa07625 86 while (priv->num_leds--)
39236901 87 led_classdev_unregister(&priv->leds[priv->num_leds].cdev);
39236901
RK
88}
89
5f7b03dc 90static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
b795e6d9 91 struct led_pwm *led, struct device_node *child)
41c42ff5 92{
5f7b03dc 93 struct led_pwm_data *led_data = &priv->leds[priv->num_leds];
aa1a6d6d 94 int ret;
41c42ff5 95
5f7b03dc 96 led_data->active_low = led->active_low;
5f7b03dc
RK
97 led_data->cdev.name = led->name;
98 led_data->cdev.default_trigger = led->default_trigger;
5f7b03dc
RK
99 led_data->cdev.brightness = LED_OFF;
100 led_data->cdev.max_brightness = led->max_brightness;
101 led_data->cdev.flags = LED_CORE_SUSPENDRESUME;
41c42ff5 102
b795e6d9
RK
103 if (child)
104 led_data->pwm = devm_of_pwm_get(dev, child, NULL);
105 else
106 led_data->pwm = devm_pwm_get(dev, led->name);
5f7b03dc
RK
107 if (IS_ERR(led_data->pwm)) {
108 ret = PTR_ERR(led_data->pwm);
109 dev_err(dev, "unable to request PWM for %s: %d\n",
110 led->name, ret);
111 return ret;
112 }
08541cbc 113
5f7b03dc 114 led_data->can_sleep = pwm_can_sleep(led_data->pwm);
9aa07625
JA
115 if (!led_data->can_sleep)
116 led_data->cdev.brightness_set = led_pwm_set;
117 else
118 led_data->cdev.brightness_set_blocking = led_pwm_set_blocking;
41c42ff5 119
7c574cf6
LT
120 led_data->period = pwm_get_period(led_data->pwm);
121 if (!led_data->period && (led->pwm_period_ns > 0))
122 led_data->period = led->pwm_period_ns;
41c42ff5 123
5f7b03dc
RK
124 ret = led_classdev_register(dev, &led_data->cdev);
125 if (ret == 0) {
126 priv->num_leds++;
f1670336 127 led_pwm_set(&led_data->cdev, led_data->cdev.brightness);
5f7b03dc
RK
128 } else {
129 dev_err(dev, "failed to register PWM led for %s: %d\n",
130 led->name, ret);
131 }
132
133 return ret;
134}
c971ff18 135
b795e6d9 136static int led_pwm_create_of(struct device *dev, struct led_pwm_priv *priv)
41c42ff5 137{
08541cbc 138 struct device_node *child;
b795e6d9
RK
139 struct led_pwm led;
140 int ret = 0;
41c42ff5 141
b795e6d9 142 memset(&led, 0, sizeof(led));
08541cbc 143
b795e6d9
RK
144 for_each_child_of_node(dev->of_node, child) {
145 led.name = of_get_property(child, "label", NULL) ? :
146 child->name;
08541cbc 147
b795e6d9 148 led.default_trigger = of_get_property(child,
08541cbc 149 "linux,default-trigger", NULL);
b0571e7e 150 led.active_low = of_property_read_bool(child, "active-low");
08541cbc 151 of_property_read_u32(child, "max-brightness",
b795e6d9 152 &led.max_brightness);
c971ff18 153
b795e6d9
RK
154 ret = led_pwm_add(dev, priv, &led, child);
155 if (ret) {
08541cbc 156 of_node_put(child);
b795e6d9 157 break;
08541cbc 158 }
08541cbc
PU
159 }
160
aa1a6d6d 161 return ret;
08541cbc
PU
162}
163
164static int led_pwm_probe(struct platform_device *pdev)
165{
87aae1ea 166 struct led_pwm_platform_data *pdata = dev_get_platdata(&pdev->dev);
08541cbc 167 struct led_pwm_priv *priv;
aa1a6d6d
PU
168 int count, i;
169 int ret = 0;
170
171 if (pdata)
172 count = pdata->num_leds;
173 else
174 count = of_get_child_count(pdev->dev.of_node);
175
176 if (!count)
177 return -EINVAL;
08541cbc 178
aa1a6d6d
PU
179 priv = devm_kzalloc(&pdev->dev, sizeof_pwm_leds_priv(count),
180 GFP_KERNEL);
181 if (!priv)
182 return -ENOMEM;
08541cbc 183
aa1a6d6d
PU
184 if (pdata) {
185 for (i = 0; i < count; i++) {
b795e6d9
RK
186 ret = led_pwm_add(&pdev->dev, priv, &pdata->leds[i],
187 NULL);
5f7b03dc
RK
188 if (ret)
189 break;
08541cbc 190 }
08541cbc 191 } else {
b795e6d9 192 ret = led_pwm_create_of(&pdev->dev, priv);
5f7b03dc
RK
193 }
194
195 if (ret) {
196 led_pwm_cleanup(priv);
197 return ret;
41c42ff5
LF
198 }
199
0f86815a 200 platform_set_drvdata(pdev, priv);
41c42ff5
LF
201
202 return 0;
41c42ff5
LF
203}
204
678e8a6b 205static int led_pwm_remove(struct platform_device *pdev)
41c42ff5 206{
0f86815a 207 struct led_pwm_priv *priv = platform_get_drvdata(pdev);
41c42ff5 208
39236901 209 led_pwm_cleanup(priv);
41c42ff5 210
41c42ff5
LF
211 return 0;
212}
213
08541cbc
PU
214static const struct of_device_id of_pwm_leds_match[] = {
215 { .compatible = "pwm-leds", },
216 {},
217};
218MODULE_DEVICE_TABLE(of, of_pwm_leds_match);
219
41c42ff5
LF
220static struct platform_driver led_pwm_driver = {
221 .probe = led_pwm_probe,
df07cf81 222 .remove = led_pwm_remove,
41c42ff5
LF
223 .driver = {
224 .name = "leds_pwm",
1e08f72d 225 .of_match_table = of_pwm_leds_match,
41c42ff5
LF
226 },
227};
228
892a8843 229module_platform_driver(led_pwm_driver);
41c42ff5
LF
230
231MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
49651c6c
UKK
232MODULE_DESCRIPTION("generic PWM LED driver");
233MODULE_LICENSE("GPL v2");
41c42ff5 234MODULE_ALIAS("platform:leds-pwm");