Re: [PATCH] leds: leds-pwm: Convert to use devm_get_pwm

From: Bryan Wu
Date: Fri Nov 09 2012 - 20:49:05 EST


On Wed, Nov 7, 2012 at 3:42 AM, Peter Ujfalusi <peter.ujfalusi@xxxxxx> wrote:
> Update the driver to use the new API for requesting pwm so we can take
> advantage of the pwm_lookup table to find the correct pwm to be used for the
> LED functionality.
> If the devm_get_pwm fails we fall back to legacy mode to try to get the pwm.
>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> ---
> drivers/leds/leds-pwm.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c
> index f2e44c7..6bf9445 100644
> --- a/drivers/leds/leds-pwm.c
> +++ b/drivers/leds/leds-pwm.c
> @@ -47,6 +47,19 @@ static void led_pwm_set(struct led_classdev *led_cdev,
> }
> }
>
> +static struct pwm_device *led_pwm_request_pwm(struct platform_device *pdev,
> + struct led_pwm *cur_led)
> +{
> + struct pwm_device *pwm;
> +
> + pwm = devm_pwm_get(&pdev->dev, cur_led->name);
> + if (IS_ERR(pwm)) {
> + dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
> + pwm = pwm_request(cur_led->pwm_id, cur_led->name);

Looks good, but why we still need to keep the old API pwm_request(),
if devm_pwm_get() is the right replacement. AFAIK, devm_***() API will
help to clean up if device probing fails.

So if it is good enough, we can just replace pwm_request() to the devm_pwm_get()

Thanks,
-Bryan

> + }
> + return pwm;
> +}
> +
> static int led_pwm_probe(struct platform_device *pdev)
> {
> struct led_pwm_platform_data *pdata = pdev->dev.platform_data;
> @@ -67,8 +80,7 @@ static int led_pwm_probe(struct platform_device *pdev)
> cur_led = &pdata->leds[i];
> led_dat = &leds_data[i];
>
> - led_dat->pwm = pwm_request(cur_led->pwm_id,
> - cur_led->name);
> + led_dat->pwm = led_pwm_request_pwm(pdev, cur_led);
> if (IS_ERR(led_dat->pwm)) {
> ret = PTR_ERR(led_dat->pwm);
> dev_err(&pdev->dev, "unable to request PWM %d\n",
> --
> 1.8.0
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/