leds: trigger: gpio: Use threaded IRQ

This both simplifies the code because we can drop the workqueue
indirection, and it enables using the trigger for GPIOs that work with
threaded IRQs themselves.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>

diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
index 93d6b82e64372a55cd0eb065b93cdcab20588adb..8891e88d54dd0cddda8833eb12012c00ce45fda6 100644 (file)
--- a/drivers/leds/trigger/ledtrig-gpio.c
+++ b/drivers/leds/trigger/ledtrig-gpio.c
@@ -14,14 +14,12 @@
 #include <linux/init.h>
 #include <linux/gpio.h>
 #include <linux/interrupt.h>
-#include <linux/workqueue.h>
 #include <linux/leds.h>
 #include <linux/slab.h>
 #include "../leds.h"
 
 struct gpio_trig_data {
        struct led_classdev *led;
-       struct work_struct work;
 
        unsigned desired_brightness;    /* desired brightness when led is on */
        unsigned inverted;              /* true when gpio is inverted */
@@ -32,22 +30,8 @@ static irqreturn_t gpio_trig_irq(int irq, void *_led)
 {
        struct led_classdev *led = _led;
        struct gpio_trig_data *gpio_data = led->trigger_data;
-
-       /* just schedule_work since gpio_get_value can sleep */
-       schedule_work(&gpio_data->work);
-
-       return IRQ_HANDLED;
-};
-
-static void gpio_trig_work(struct work_struct *work)
-{
-       struct gpio_trig_data *gpio_data = container_of(work,
-                       struct gpio_trig_data, work);
        int tmp;
 
-       if (!gpio_data->gpio)
-               return;
-
        tmp = gpio_get_value_cansleep(gpio_data->gpio);
        if (gpio_data->inverted)
                tmp = !tmp;
@@ -61,6 +45,8 @@ static void gpio_trig_work(struct work_struct *work)
        } else {
                led_set_brightness_nosleep(gpio_data->led, LED_OFF);
        }
+
+       return IRQ_HANDLED;
 }
 
 static ssize_t gpio_trig_brightness_show(struct device *dev,
@@ -120,7 +106,7 @@ static ssize_t gpio_trig_inverted_store(struct device *dev,
        gpio_data->inverted = inverted;
 
        /* After inverting, we need to update the LED. */
-       schedule_work(&gpio_data->work);
+       gpio_trig_irq(0, led);
 
        return n;
 }
@@ -147,7 +133,6 @@ static ssize_t gpio_trig_gpio_store(struct device *dev,
        ret = sscanf(buf, "%u", &gpio);
        if (ret < 1) {
                dev_err(dev, "couldn't read gpio number\n");
-               flush_work(&gpio_data->work);
                return -EINVAL;
        }
 
@@ -161,8 +146,8 @@ static ssize_t gpio_trig_gpio_store(struct device *dev,
                return n;
        }
 
-       ret = request_irq(gpio_to_irq(gpio), gpio_trig_irq,
-                       IRQF_SHARED | IRQF_TRIGGER_RISING
+       ret = request_threaded_irq(gpio_to_irq(gpio), NULL, gpio_trig_irq,
+                       IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_RISING
                        | IRQF_TRIGGER_FALLING, "ledtrig-gpio", led);
        if (ret) {
                dev_err(dev, "request_irq failed with error %d\n", ret);
@@ -171,7 +156,7 @@ static ssize_t gpio_trig_gpio_store(struct device *dev,
                        free_irq(gpio_to_irq(gpio_data->gpio), led);
                gpio_data->gpio = gpio;
                /* After changing the GPIO, we need to update the LED. */
-               schedule_work(&gpio_data->work);
+               gpio_trig_irq(0, led);
        }
 
        return ret ? ret : n;
@@ -201,7 +186,6 @@ static void gpio_trig_activate(struct led_classdev *led)
 
        gpio_data->led = led;
        led->trigger_data = gpio_data;
-       INIT_WORK(&gpio_data->work, gpio_trig_work);
        led->activated = true;
 
        return;
@@ -224,7 +208,6 @@ static void gpio_trig_deactivate(struct led_classdev *led)
                device_remove_file(led->dev, &dev_attr_gpio);
                device_remove_file(led->dev, &dev_attr_inverted);
                device_remove_file(led->dev, &dev_attr_desired_brightness);
-               flush_work(&gpio_data->work);
                if (gpio_data->gpio != 0)
                        free_irq(gpio_to_irq(gpio_data->gpio), led);
                kfree(gpio_data);