libceph: move r_reply_op_{len,result} into struct ceph_osd_req_op
[linux-2.6-block.git] / drivers / leds / leds-lt3593.c
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1/*
2 * LEDs driver for LT3593 controllers
3 *
4 * See the datasheet at http://cds.linear.com/docs/Datasheet/3593f.pdf
5 *
6 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
7 *
8 * Based on leds-gpio.c,
9 *
10 * Copyright (C) 2007 8D Technologies inc.
11 * Raphael Assenat <raph@8d.com>
12 * Copyright (C) 2008 Freescale Semiconductor, Inc.
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License version 2 as
16 * published by the Free Software Foundation.
17 */
18
19#include <linux/kernel.h>
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20#include <linux/platform_device.h>
21#include <linux/leds.h>
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22#include <linux/delay.h>
23#include <linux/gpio.h>
5a0e3ad6 24#include <linux/slab.h>
54f4dedb 25#include <linux/module.h>
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26
27struct lt3593_led_data {
28 struct led_classdev cdev;
29 unsigned gpio;
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30};
31
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32static int lt3593_led_set(struct led_classdev *led_cdev,
33 enum led_brightness value)
a8dd18fe 34{
a8dd18fe 35 struct lt3593_led_data *led_dat =
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36 container_of(led_cdev, struct lt3593_led_data, cdev);
37 int pulses;
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38
39 /*
40 * The LT3593 resets its internal current level register to the maximum
41 * level on the first falling edge on the control pin. Each following
42 * falling edge decreases the current level by 625uA. Up to 32 pulses
43 * can be sent, so the maximum power reduction is 20mA.
44 * After a timeout of 128us, the value is taken from the register and
45 * applied is to the output driver.
46 */
47
a0011f1b 48 if (value == 0) {
a8dd18fe 49 gpio_set_value_cansleep(led_dat->gpio, 0);
a0011f1b 50 return 0;
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51 }
52
a0011f1b 53 pulses = 32 - (value * 32) / 255;
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54
55 if (pulses == 0) {
56 gpio_set_value_cansleep(led_dat->gpio, 0);
57 mdelay(1);
58 gpio_set_value_cansleep(led_dat->gpio, 1);
a0011f1b 59 return 0;
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60 }
61
62 gpio_set_value_cansleep(led_dat->gpio, 1);
63
64 while (pulses--) {
65 gpio_set_value_cansleep(led_dat->gpio, 0);
66 udelay(1);
67 gpio_set_value_cansleep(led_dat->gpio, 1);
68 udelay(1);
69 }
a8dd18fe 70
a0011f1b 71 return 0;
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72}
73
98ea1ea2 74static int create_lt3593_led(const struct gpio_led *template,
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75 struct lt3593_led_data *led_dat, struct device *parent)
76{
77 int ret, state;
78
79 /* skip leds on GPIOs that aren't available */
80 if (!gpio_is_valid(template->gpio)) {
30e5c3e6 81 dev_info(parent, "%s: skipping unavailable LT3593 LED at gpio %d (%s)\n",
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82 KBUILD_MODNAME, template->gpio, template->name);
83 return 0;
84 }
85
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86 led_dat->cdev.name = template->name;
87 led_dat->cdev.default_trigger = template->default_trigger;
88 led_dat->gpio = template->gpio;
89
a0011f1b 90 led_dat->cdev.brightness_set_blocking = lt3593_led_set;
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91
92 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
93 led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
94
95 if (!template->retain_state_suspended)
96 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
97
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98 ret = devm_gpio_request_one(parent, template->gpio, state ?
99 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
100 template->name);
a8dd18fe 101 if (ret < 0)
507d967b 102 return ret;
a8dd18fe 103
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104 ret = led_classdev_register(parent, &led_dat->cdev);
105 if (ret < 0)
95a8ff83 106 return ret;
a8dd18fe 107
30e5c3e6 108 dev_info(parent, "%s: registered LT3593 LED '%s' at GPIO %d\n",
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109 KBUILD_MODNAME, template->name, template->gpio);
110
111 return 0;
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112}
113
114static void delete_lt3593_led(struct lt3593_led_data *led)
115{
116 if (!gpio_is_valid(led->gpio))
117 return;
118
119 led_classdev_unregister(&led->cdev);
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120}
121
98ea1ea2 122static int lt3593_led_probe(struct platform_device *pdev)
a8dd18fe 123{
87aae1ea 124 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
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125 struct lt3593_led_data *leds_data;
126 int i, ret = 0;
127
128 if (!pdata)
129 return -EBUSY;
130
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131 leds_data = devm_kzalloc(&pdev->dev,
132 sizeof(struct lt3593_led_data) * pdata->num_leds,
133 GFP_KERNEL);
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134 if (!leds_data)
135 return -ENOMEM;
136
137 for (i = 0; i < pdata->num_leds; i++) {
138 ret = create_lt3593_led(&pdata->leds[i], &leds_data[i],
139 &pdev->dev);
140 if (ret < 0)
141 goto err;
142 }
143
144 platform_set_drvdata(pdev, leds_data);
145
146 return 0;
147
148err:
149 for (i = i - 1; i >= 0; i--)
150 delete_lt3593_led(&leds_data[i]);
151
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152 return ret;
153}
154
678e8a6b 155static int lt3593_led_remove(struct platform_device *pdev)
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156{
157 int i;
87aae1ea 158 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
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159 struct lt3593_led_data *leds_data;
160
161 leds_data = platform_get_drvdata(pdev);
162
163 for (i = 0; i < pdata->num_leds; i++)
164 delete_lt3593_led(&leds_data[i]);
165
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166 return 0;
167}
168
169static struct platform_driver lt3593_led_driver = {
170 .probe = lt3593_led_probe,
df07cf81 171 .remove = lt3593_led_remove,
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172 .driver = {
173 .name = "leds-lt3593",
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174 },
175};
176
892a8843 177module_platform_driver(lt3593_led_driver);
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178
179MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
180MODULE_DESCRIPTION("LED driver for LT3593 controllers");
181MODULE_LICENSE("GPL");
892a8843 182MODULE_ALIAS("platform:leds-lt3593");