blob: 4b9eea815b1a420d0b1b97966aa04292a137c4ea [file] [log] [blame]
Andreas Werner38433632014-08-27 19:52:36 +02001/*
2 * MEN 14F021P00 Board Management Controller (BMC) LEDs Driver.
3 *
4 * This is the core LED driver of the MEN 14F021P00 BMC.
5 * There are four LEDs available which can be switched on and off.
6 * STATUS LED, HOT SWAP LED, USER LED 1, USER LED 2
7 *
8 * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
14 */
15
16#include <linux/module.h>
17#include <linux/kernel.h>
18#include <linux/platform_device.h>
19#include <linux/leds.h>
20#include <linux/i2c.h>
21
22#define BMC_CMD_LED_GET_SET 0xA0
23#define BMC_BIT_LED_STATUS BIT(0)
24#define BMC_BIT_LED_HOTSWAP BIT(1)
25#define BMC_BIT_LED_USER1 BIT(2)
26#define BMC_BIT_LED_USER2 BIT(3)
27
28struct menf21bmc_led {
29 struct led_classdev cdev;
30 u8 led_bit;
31 const char *name;
32 struct i2c_client *i2c_client;
33};
34
35static struct menf21bmc_led leds[] = {
36 {
37 .name = "menf21bmc:led_status",
38 .led_bit = BMC_BIT_LED_STATUS,
39 },
40 {
41 .name = "menf21bmc:led_hotswap",
42 .led_bit = BMC_BIT_LED_HOTSWAP,
43 },
44 {
45 .name = "menf21bmc:led_user1",
46 .led_bit = BMC_BIT_LED_USER1,
47 },
48 {
49 .name = "menf21bmc:led_user2",
50 .led_bit = BMC_BIT_LED_USER2,
51 }
52};
53
54static DEFINE_MUTEX(led_lock);
55
56static void
57menf21bmc_led_set(struct led_classdev *led_cdev, enum led_brightness value)
58{
59 int led_val;
60 struct menf21bmc_led *led = container_of(led_cdev,
61 struct menf21bmc_led, cdev);
62
63 mutex_lock(&led_lock);
64 led_val = i2c_smbus_read_byte_data(led->i2c_client,
65 BMC_CMD_LED_GET_SET);
66 if (led_val < 0)
67 goto err_out;
68
69 if (value == LED_OFF)
70 led_val &= ~led->led_bit;
71 else
72 led_val |= led->led_bit;
73
74 i2c_smbus_write_byte_data(led->i2c_client,
75 BMC_CMD_LED_GET_SET, led_val);
76err_out:
77 mutex_unlock(&led_lock);
78}
79
80static int menf21bmc_led_probe(struct platform_device *pdev)
81{
82 int i;
83 int ret;
84 struct i2c_client *i2c_client = to_i2c_client(pdev->dev.parent);
85
86 for (i = 0; i < ARRAY_SIZE(leds); i++) {
87 leds[i].cdev.name = leds[i].name;
88 leds[i].cdev.brightness_set = menf21bmc_led_set;
89 leds[i].i2c_client = i2c_client;
90 ret = led_classdev_register(&pdev->dev, &leds[i].cdev);
91 if (ret < 0)
92 goto err_free_leds;
93 }
94 dev_info(&pdev->dev, "MEN 140F21P00 BMC LED device enabled\n");
95
96 return 0;
97
98err_free_leds:
99 dev_err(&pdev->dev, "failed to register LED device\n");
100
101 for (i = i - 1; i >= 0; i--)
102 led_classdev_unregister(&leds[i].cdev);
103
104 return ret;
105}
106
107static int menf21bmc_led_remove(struct platform_device *pdev)
108{
109 int i;
110
111 for (i = 0; i < ARRAY_SIZE(leds); i++)
112 led_classdev_unregister(&leds[i].cdev);
113
114 return 0;
115}
116
117static struct platform_driver menf21bmc_led = {
118 .probe = menf21bmc_led_probe,
119 .remove = menf21bmc_led_remove,
120 .driver = {
121 .name = "menf21bmc_led",
Andreas Werner38433632014-08-27 19:52:36 +0200122 },
123};
124
125module_platform_driver(menf21bmc_led);
126
127MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
128MODULE_DESCRIPTION("MEN 14F021P00 BMC led driver");
129MODULE_LICENSE("GPL v2");
130MODULE_ALIAS("platform:menf21bmc_led");