diff options
Diffstat (limited to 'drivers/leds/leds-menf21bmc.c')
-rw-r--r-- | drivers/leds/leds-menf21bmc.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/drivers/leds/leds-menf21bmc.c b/drivers/leds/leds-menf21bmc.c new file mode 100644 index 000000000..4b9eea815 --- /dev/null +++ b/drivers/leds/leds-menf21bmc.c @@ -0,0 +1,130 @@ +/* + * 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 + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#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 = led_classdev_register(&pdev->dev, &leds[i].cdev); + if (ret < 0) + goto err_free_leds; + } + dev_info(&pdev->dev, "MEN 140F21P00 BMC LED device enabled\n"); + + return 0; + +err_free_leds: + dev_err(&pdev->dev, "failed to register LED device\n"); + + for (i = i - 1; i >= 0; i--) + led_classdev_unregister(&leds[i].cdev); + + return ret; +} + +static int menf21bmc_led_remove(struct platform_device *pdev) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(leds); i++) + led_classdev_unregister(&leds[i].cdev); + + return 0; +} + +static struct platform_driver menf21bmc_led = { + .probe = menf21bmc_led_probe, + .remove = menf21bmc_led_remove, + .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"); |