| Andreas Werner | 3843363 | 2014-08-27 19:52:36 +0200 | [diff] [blame] | 1 | /* |
| 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 | |
| 28 | struct menf21bmc_led { |
| 29 | struct led_classdev cdev; |
| 30 | u8 led_bit; |
| 31 | const char *name; |
| 32 | struct i2c_client *i2c_client; |
| 33 | }; |
| 34 | |
| 35 | static 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 | |
| 54 | static DEFINE_MUTEX(led_lock); |
| 55 | |
| 56 | static void |
| 57 | menf21bmc_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); |
| 76 | err_out: |
| 77 | mutex_unlock(&led_lock); |
| 78 | } |
| 79 | |
| 80 | static 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 | |
| 98 | err_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 | |
| 107 | static 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 | |
| 117 | static struct platform_driver menf21bmc_led = { |
| 118 | .probe = menf21bmc_led_probe, |
| 119 | .remove = menf21bmc_led_remove, |
| 120 | .driver = { |
| 121 | .name = "menf21bmc_led", |
| 122 | .owner = THIS_MODULE, |
| 123 | }, |
| 124 | }; |
| 125 | |
| 126 | module_platform_driver(menf21bmc_led); |
| 127 | |
| 128 | MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>"); |
| 129 | MODULE_DESCRIPTION("MEN 14F021P00 BMC led driver"); |
| 130 | MODULE_LICENSE("GPL v2"); |
| 131 | MODULE_ALIAS("platform:menf21bmc_led"); |