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authorThadeu Lima de Souza Cascardo <cascardo@holoscopio.com>2009-08-26 14:29:31 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-08-26 20:06:53 -0700
commit48cccd26f36511ddb6aeca07485ecf2829683907 (patch)
tree713e481085d33d73a8cf43131317db6c4aa206aa
parentbdf57de4e6abc389cc3f3bd94ec15cce74cf6f4b (diff)
downloadlinux-48cccd26f36511ddb6aeca07485ecf2829683907.tar.bz2
leds: fix multiple requests and releases of IRQ for GPIO LED Trigger
When setting the same GPIO number, multiple IRQ shared requests will be done without freing the previous request. It will also try to free a failed request or an already freed IRQ if 0 was written to the gpio file. All these oops and leaks were fixed with the following solution: keep the previous allocated GPIO (if any) still allocated in case the new request fails. The alternative solution would desallocate the previous allocated GPIO and set gpio as 0. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> Signed-off-by: Samuel R. C. Vale <srcvale@holoscopio.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--drivers/leds/ledtrig-gpio.c21
1 files changed, 14 insertions, 7 deletions
diff --git a/drivers/leds/ledtrig-gpio.c b/drivers/leds/ledtrig-gpio.c
index a247ae63374f..8183b81fca84 100644
--- a/drivers/leds/ledtrig-gpio.c
+++ b/drivers/leds/ledtrig-gpio.c
@@ -146,20 +146,26 @@ static ssize_t gpio_trig_gpio_store(struct device *dev,
return -EINVAL;
}
+ if (gpio_data->gpio == gpio)
+ return n;
+
if (!gpio) {
- free_irq(gpio_to_irq(gpio_data->gpio), led);
+ if (gpio_data->gpio != 0)
+ free_irq(gpio_to_irq(gpio_data->gpio), led);
+ gpio_data->gpio = 0;
return n;
}
- if (gpio_data->gpio > 0 && gpio_data->gpio != gpio)
- free_irq(gpio_to_irq(gpio_data->gpio), led);
-
- gpio_data->gpio = gpio;
ret = request_irq(gpio_to_irq(gpio), gpio_trig_irq,
IRQF_SHARED | IRQF_TRIGGER_RISING
| IRQF_TRIGGER_FALLING, "ledtrig-gpio", led);
- if (ret)
+ if (ret) {
dev_err(dev, "request_irq failed with error %d\n", ret);
+ } else {
+ if (gpio_data->gpio != 0)
+ free_irq(gpio_to_irq(gpio_data->gpio), led);
+ gpio_data->gpio = gpio;
+ }
return ret ? ret : n;
}
@@ -211,7 +217,8 @@ static void gpio_trig_deactivate(struct led_classdev *led)
device_remove_file(led->dev, &dev_attr_inverted);
device_remove_file(led->dev, &dev_attr_desired_brightness);
flush_work(&gpio_data->work);
- free_irq(gpio_to_irq(gpio_data->gpio),led);
+ if (gpio_data->gpio != 0)
+ free_irq(gpio_to_irq(gpio_data->gpio), led);
kfree(gpio_data);
}
}