aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-menf21bmc.c
blob: 6b1b471606026dd7cf22f4ec903ee3ac71deb09c (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  MEN 14F021P00 Board Management Controller (BMC) LEDs Driver.
 *
 *  This is the core LED driver of the MEN 14F021P00 BMC.
 *  There are four LEDs available which can be switched on and off.
 *  STATUS LED, HOT SWAP LED, USER LED 1, USER LED 2
 *
 *  Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/i2c.h>

#define BMC_CMD_LED_GET_SET	0xA0
#define BMC_BIT_LED_STATUS	BIT(0)
#define BMC_BIT_LED_HOTSWAP	BIT(1)
#define BMC_BIT_LED_USER1	BIT(2)
#define BMC_BIT_LED_USER2	BIT(3)

struct menf21bmc_led {
	struct led_classdev cdev;
	u8 led_bit;
	const char *name;
	struct i2c_client *i2c_client;
};

static struct menf21bmc_led leds[] = {
	{
		.name = "menf21bmc:led_status",
		.led_bit = BMC_BIT_LED_STATUS,
	},
	{
		.name = "menf21bmc:led_hotswap",
		.led_bit = BMC_BIT_LED_HOTSWAP,
	},
	{
		.name = "menf21bmc:led_user1",
		.led_bit = BMC_BIT_LED_USER1,
	},
	{
		.name = "menf21bmc:led_user2",
		.led_bit = BMC_BIT_LED_USER2,
	}
};

static DEFINE_MUTEX(led_lock);

static void
menf21bmc_led_set(struct led_classdev *led_cdev, enum led_brightness value)
{
	int led_val;
	struct menf21bmc_led *led = container_of(led_cdev,
					struct menf21bmc_led, cdev);

	mutex_lock(&led_lock);
	led_val = i2c_smbus_read_byte_data(led->i2c_client,
					   BMC_CMD_LED_GET_SET);
	if (led_val < 0)
		goto err_out;

	if (value == LED_OFF)
		led_val &= ~led->led_bit;
	else
		led_val |= led->led_bit;

	i2c_smbus_write_byte_data(led->i2c_client,
				  BMC_CMD_LED_GET_SET, led_val);
err_out:
	mutex_unlock(&led_lock);
}

static int menf21bmc_led_probe(struct platform_device *pdev)
{
	int i;
	int ret;
	struct i2c_client *i2c_client = to_i2c_client(pdev->dev.parent);

	for (i = 0; i < ARRAY_SIZE(leds); i++) {
		leds[i].cdev.name = leds[i].name;
		leds[i].cdev.brightness_set = menf21bmc_led_set;
		leds[i].i2c_client = i2c_client;
		ret = devm_led_classdev_register(&pdev->dev, &leds[i].cdev);
		if (ret < 0) {
			dev_err(&pdev->dev, "failed to register LED device\n");
			return ret;
		}
	}
	dev_info(&pdev->dev, "MEN 140F21P00 BMC LED device enabled\n");

	return 0;

}

static struct platform_driver menf21bmc_led = {
	.probe		= menf21bmc_led_probe,
	.driver		= {
		.name		= "menf21bmc_led",
	},
};

module_platform_driver(menf21bmc_led);

MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
MODULE_DESCRIPTION("MEN 14F021P00 BMC led driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:menf21bmc_led");