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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * MEN 14F021P00 Board Management Controller (BMC) LEDs Driver.4 *5 * This is the core LED driver of the MEN 14F021P00 BMC.6 * There are four LEDs available which can be switched on and off.7 * STATUS LED, HOT SWAP LED, USER LED 1, USER LED 28 *9 * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH10 */11 12#include <linux/module.h>13#include <linux/kernel.h>14#include <linux/platform_device.h>15#include <linux/leds.h>16#include <linux/i2c.h>17 18#define BMC_CMD_LED_GET_SET 0xA019#define BMC_BIT_LED_STATUS BIT(0)20#define BMC_BIT_LED_HOTSWAP BIT(1)21#define BMC_BIT_LED_USER1 BIT(2)22#define BMC_BIT_LED_USER2 BIT(3)23 24struct menf21bmc_led {25 struct led_classdev cdev;26 u8 led_bit;27 const char *name;28 struct i2c_client *i2c_client;29};30 31static struct menf21bmc_led leds[] = {32 {33 .name = "menf21bmc:led_status",34 .led_bit = BMC_BIT_LED_STATUS,35 },36 {37 .name = "menf21bmc:led_hotswap",38 .led_bit = BMC_BIT_LED_HOTSWAP,39 },40 {41 .name = "menf21bmc:led_user1",42 .led_bit = BMC_BIT_LED_USER1,43 },44 {45 .name = "menf21bmc:led_user2",46 .led_bit = BMC_BIT_LED_USER2,47 }48};49 50static DEFINE_MUTEX(led_lock);51 52static void53menf21bmc_led_set(struct led_classdev *led_cdev, enum led_brightness value)54{55 int led_val;56 struct menf21bmc_led *led = container_of(led_cdev,57 struct menf21bmc_led, cdev);58 59 mutex_lock(&led_lock);60 led_val = i2c_smbus_read_byte_data(led->i2c_client,61 BMC_CMD_LED_GET_SET);62 if (led_val < 0)63 goto err_out;64 65 if (value == LED_OFF)66 led_val &= ~led->led_bit;67 else68 led_val |= led->led_bit;69 70 i2c_smbus_write_byte_data(led->i2c_client,71 BMC_CMD_LED_GET_SET, led_val);72err_out:73 mutex_unlock(&led_lock);74}75 76static int menf21bmc_led_probe(struct platform_device *pdev)77{78 int i;79 int ret;80 struct i2c_client *i2c_client = to_i2c_client(pdev->dev.parent);81 82 for (i = 0; i < ARRAY_SIZE(leds); i++) {83 leds[i].cdev.name = leds[i].name;84 leds[i].cdev.brightness_set = menf21bmc_led_set;85 leds[i].i2c_client = i2c_client;86 ret = devm_led_classdev_register(&pdev->dev, &leds[i].cdev);87 if (ret < 0) {88 dev_err(&pdev->dev, "failed to register LED device\n");89 return ret;90 }91 }92 dev_info(&pdev->dev, "MEN 140F21P00 BMC LED device enabled\n");93 94 return 0;95 96}97 98static struct platform_driver menf21bmc_led = {99 .probe = menf21bmc_led_probe,100 .driver = {101 .name = "menf21bmc_led",102 },103};104 105module_platform_driver(menf21bmc_led);106 107MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");108MODULE_DESCRIPTION("MEN 14F021P00 BMC led driver");109MODULE_LICENSE("GPL v2");110MODULE_ALIAS("platform:menf21bmc_led");111