diff options
Diffstat (limited to 'drivers/leds/leds-ot200.c')
-rw-r--r-- | drivers/leds/leds-ot200.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/leds/leds-ot200.c b/drivers/leds/leds-ot200.c new file mode 100644 index 000000000..12af1127d --- /dev/null +++ b/drivers/leds/leds-ot200.c @@ -0,0 +1,152 @@ +/* + * Bachmann ot200 leds driver. + * + * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> + * Christian Gmeiner <christian.gmeiner@gmail.com> + * + * License: GPL as published by the FSF. + */ + +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/leds.h> +#include <linux/io.h> +#include <linux/module.h> + + +struct ot200_led { + struct led_classdev cdev; + const char *name; + unsigned long port; + u8 mask; +}; + +/* + * The device has three leds on the back panel (led_err, led_init and led_run) + * and can handle up to seven leds on the front panel. + */ + +static struct ot200_led leds[] = { + { + .name = "led_run", + .port = 0x5a, + .mask = BIT(0), + }, + { + .name = "led_init", + .port = 0x5a, + .mask = BIT(1), + }, + { + .name = "led_err", + .port = 0x5a, + .mask = BIT(2), + }, + { + .name = "led_1", + .port = 0x49, + .mask = BIT(6), + }, + { + .name = "led_2", + .port = 0x49, + .mask = BIT(5), + }, + { + .name = "led_3", + .port = 0x49, + .mask = BIT(4), + }, + { + .name = "led_4", + .port = 0x49, + .mask = BIT(3), + }, + { + .name = "led_5", + .port = 0x49, + .mask = BIT(2), + }, + { + .name = "led_6", + .port = 0x49, + .mask = BIT(1), + }, + { + .name = "led_7", + .port = 0x49, + .mask = BIT(0), + } +}; + +static DEFINE_SPINLOCK(value_lock); + +/* + * we need to store the current led states, as it is not + * possible to read the current led state via inb(). + */ +static u8 leds_back; +static u8 leds_front; + +static void ot200_led_brightness_set(struct led_classdev *led_cdev, + enum led_brightness value) +{ + struct ot200_led *led = container_of(led_cdev, struct ot200_led, cdev); + u8 *val; + unsigned long flags; + + spin_lock_irqsave(&value_lock, flags); + + if (led->port == 0x49) + val = &leds_front; + else if (led->port == 0x5a) + val = &leds_back; + else + BUG(); + + if (value == LED_OFF) + *val &= ~led->mask; + else + *val |= led->mask; + + outb(*val, led->port); + spin_unlock_irqrestore(&value_lock, flags); +} + +static int ot200_led_probe(struct platform_device *pdev) +{ + int i; + int ret; + + for (i = 0; i < ARRAY_SIZE(leds); i++) { + + leds[i].cdev.name = leds[i].name; + leds[i].cdev.brightness_set = ot200_led_brightness_set; + + ret = devm_led_classdev_register(&pdev->dev, &leds[i].cdev); + if (ret < 0) + return ret; + } + + leds_front = 0; /* turn off all front leds */ + leds_back = BIT(1); /* turn on init led */ + outb(leds_front, 0x49); + outb(leds_back, 0x5a); + + return 0; +} + +static struct platform_driver ot200_led_driver = { + .probe = ot200_led_probe, + .driver = { + .name = "leds-ot200", + }, +}; + +module_platform_driver(ot200_led_driver); + +MODULE_AUTHOR("Sebastian A. Siewior <bigeasy@linutronix.de>"); +MODULE_DESCRIPTION("ot200 LED driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:leds-ot200"); |