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1/*2 * Bachmann ot200 leds driver.3 *4 * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>5 * Christian Gmeiner <christian.gmeiner@gmail.com>6 *7 * License: GPL as published by the FSF.8 */9 10#include <linux/kernel.h>11#include <linux/platform_device.h>12#include <linux/slab.h>13#include <linux/leds.h>14#include <linux/io.h>15#include <linux/module.h>16 17 18struct ot200_led {19 struct led_classdev cdev;20 const char *name;21 unsigned long port;22 u8 mask;23};24 25/*26 * The device has three leds on the back panel (led_err, led_init and led_run)27 * and can handle up to seven leds on the front panel.28 */29 30static struct ot200_led leds[] = {31 {32 .name = "led_run",33 .port = 0x5a,34 .mask = BIT(0),35 },36 {37 .name = "led_init",38 .port = 0x5a,39 .mask = BIT(1),40 },41 {42 .name = "led_err",43 .port = 0x5a,44 .mask = BIT(2),45 },46 {47 .name = "led_1",48 .port = 0x49,49 .mask = BIT(6),50 },51 {52 .name = "led_2",53 .port = 0x49,54 .mask = BIT(5),55 },56 {57 .name = "led_3",58 .port = 0x49,59 .mask = BIT(4),60 },61 {62 .name = "led_4",63 .port = 0x49,64 .mask = BIT(3),65 },66 {67 .name = "led_5",68 .port = 0x49,69 .mask = BIT(2),70 },71 {72 .name = "led_6",73 .port = 0x49,74 .mask = BIT(1),75 },76 {77 .name = "led_7",78 .port = 0x49,79 .mask = BIT(0),80 }81};82 83static DEFINE_SPINLOCK(value_lock);84 85/*86 * we need to store the current led states, as it is not87 * possible to read the current led state via inb().88 */89static u8 leds_back;90static u8 leds_front;91 92static void ot200_led_brightness_set(struct led_classdev *led_cdev,93 enum led_brightness value)94{95 struct ot200_led *led = container_of(led_cdev, struct ot200_led, cdev);96 u8 *val;97 unsigned long flags;98 99 spin_lock_irqsave(&value_lock, flags);100 101 if (led->port == 0x49)102 val = &leds_front;103 else if (led->port == 0x5a)104 val = &leds_back;105 else106 BUG();107 108 if (value == LED_OFF)109 *val &= ~led->mask;110 else111 *val |= led->mask;112 113 outb(*val, led->port);114 spin_unlock_irqrestore(&value_lock, flags);115}116 117static int ot200_led_probe(struct platform_device *pdev)118{119 int i;120 int ret;121 122 for (i = 0; i < ARRAY_SIZE(leds); i++) {123 124 leds[i].cdev.name = leds[i].name;125 leds[i].cdev.brightness_set = ot200_led_brightness_set;126 127 ret = devm_led_classdev_register(&pdev->dev, &leds[i].cdev);128 if (ret < 0)129 return ret;130 }131 132 leds_front = 0; /* turn off all front leds */133 leds_back = BIT(1); /* turn on init led */134 outb(leds_front, 0x49);135 outb(leds_back, 0x5a);136 137 return 0;138}139 140static struct platform_driver ot200_led_driver = {141 .probe = ot200_led_probe,142 .driver = {143 .name = "leds-ot200",144 },145};146 147module_platform_driver(ot200_led_driver);148 149MODULE_AUTHOR("Sebastian A. Siewior <bigeasy@linutronix.de>");150MODULE_DESCRIPTION("ot200 LED driver");151MODULE_LICENSE("GPL");152MODULE_ALIAS("platform:leds-ot200");153