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Subject[PATCH v4] s3c/s3c24xx: arm: leds: Make s3c24xx LEDS driver use gpiolib. Fix error disabling pull during probe.
Make s3c24xx LEDS driver use gpiolib. Fix error disabling pull during probe.

Signed-off-by: Denis Kuzmenko <linux@solonet.org.ua>
---
There is a comment "no point in having a pull-up if we are always driving"
but code was actually enabled pull-resistor for that case probably because of
function parameter misunderstanding (1 - disables, 0 - enables). So this was
changed to another function which takes alphabetically defined constant as
parameter.
Tested on Mini2440 board which implements most complex case where both
S3C24XX_LEDF_ACTLOW and S3C24XX_LEDF_TRISTATE are set.

Changes v1->v2
Fix typo's and style problems.
Changes v2->v3
Remove pull-resistor enabling code for case of S3C24XX_LEDF_TRISTATE
flag is set
Changes v3->v4
!! approach for XOR operation with (pd->flags & S3C24XX_LEDF_ACTLOW)
(otherwise code will became buggy when S3C24XX_LEDF_ACTLOW valu will be changed)

See https://lkml.org/lkml/2011/11/22/42 and https://lkml.org/lkml/2011/12/13/338
previous for discussions.

diff --git a/drivers/leds/leds-s3c24xx.c b/drivers/leds/leds-s3c24xx.c
index 29f8b0f..8062664 100644
--- a/drivers/leds/leds-s3c24xx.c
+++ b/drivers/leds/leds-s3c24xx.c
@@ -46,23 +46,29 @@ static void s3c24xx_led_set(struct led_classdev *led_cdev,
struct s3c24xx_gpio_led *led = to_gpio(led_cdev);
struct s3c24xx_led_platdata *pd = led->pdata;

- /* there will be a short delay between setting the output and
- * going from output to input when using tristate. */
-
- s3c2410_gpio_setpin(pd->gpio, (value ? 1 : 0) ^
- (pd->flags & S3C24XX_LEDF_ACTLOW));
-
- if (pd->flags & S3C24XX_LEDF_TRISTATE)
- s3c2410_gpio_cfgpin(pd->gpio,
- value ? S3C2410_GPIO_OUTPUT : S3C2410_GPIO_INPUT);
+ if (pd->flags & S3C24XX_LEDF_TRISTATE) {
+ if (value) {
+ /* invert value if S3C24XX_LEDF_ACTLOW is set */
+ gpio_direction_output(pd->gpio,
+ !!value ^ !!(pd->flags & S3C24XX_LEDF_ACTLOW));
+ } else {
+ gpio_direction_input(pd->gpio);
+ }
+ } else {
+ /* invert value if S3C24XX_LEDF_ACTLOW is set */
+ gpio_direction_output(pd->gpio,
+ !!value ^ !!(pd->flags & S3C24XX_LEDF_ACTLOW));
+ }

}

static int s3c24xx_led_remove(struct platform_device *dev)
{
+ struct s3c24xx_led_platdata *pdata = dev->dev.platform_data;
struct s3c24xx_gpio_led *led = pdev_to_gpio(dev);

led_classdev_unregister(&led->cdev);
+ gpio_free(pdata->gpio);
kfree(led);

return 0;
@@ -77,7 +83,8 @@ static int s3c24xx_led_probe(struct platform_device *dev)
led = kzalloc(sizeof(struct s3c24xx_gpio_led), GFP_KERNEL);
if (led == NULL) {
dev_err(&dev->dev, "No memory for device\n");
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_kzalloc;
}

platform_set_drvdata(dev, led);
@@ -89,15 +96,24 @@ static int s3c24xx_led_probe(struct platform_device *dev)

led->pdata = pdata;

- /* no point in having a pull-up if we are always driving */
+ ret = gpio_request(pdata->gpio, pdata->name);
+ if (ret < 0) {
+ dev_err(&dev->dev, "gpio_request failed\n");
+ goto err_gpio_request;
+ }

+ /* apply GPIO settings and initially turn off the LED */
if (pdata->flags & S3C24XX_LEDF_TRISTATE) {
- s3c2410_gpio_setpin(pdata->gpio, 0);
- s3c2410_gpio_cfgpin(pdata->gpio, S3C2410_GPIO_INPUT);
+ ret = gpio_direction_input(pdata->gpio);
} else {
- s3c2410_gpio_pullup(pdata->gpio, 0);
- s3c2410_gpio_setpin(pdata->gpio, 0);
- s3c2410_gpio_cfgpin(pdata->gpio, S3C2410_GPIO_OUTPUT);
+ /* no point in having a pull-up as we are always driving */
+ s3c_gpio_setpull(pdata->gpio, S3C_GPIO_PULL_NONE);
+ ret = gpio_direction_output(pdata->gpio,
+ !!(pdata->flags & S3C24XX_LEDF_ACTLOW));
+ }
+ if (ret < 0) {
+ dev_err(&dev->dev, "can't set gpio direction\n");
+ goto err_gpio_set_direction;
}

/* register our new led device */
@@ -105,11 +121,18 @@ static int s3c24xx_led_probe(struct platform_device *dev)
ret = led_classdev_register(&dev->dev, &led->cdev);
if (ret < 0) {
dev_err(&dev->dev, "led_classdev_register failed\n");
- kfree(led);
- return ret;
+ goto err_led_classdev_register;
}

return 0;
+
+err_led_classdev_register:
+err_gpio_set_direction:
+ gpio_free(pdata->gpio);
+err_gpio_request:
+ kfree(led);
+err_kzalloc:
+ return ret;
}

static struct platform_driver s3c24xx_led_driver = {

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