[PATCH] backlight: pwm_bl: move suspend/resume entries from platform_driver to driver.pm

Eric Miao eric.y.miao at gmail.com
Wed Nov 30 21:02:54 EST 2011


On Thu, Dec 1, 2011 at 9:53 AM, Barry Song <Barry.Song at csr.com> wrote:
> From: Xiangzhen Ye <Xiangzhen.Ye at csr.com>
>
> At first, people are moving suspend/resume entries from platform_driver
> to driver.pm for many drivers.
> On the other hand, if we use swsusp to do hibernation for an embedded
> system using pwm_bl, in the process of preparing snapshot, backlight
> will be off and make lcd black screen. This gives bad user experiences.
> This patch will fix this issue as swsusp will go to call pm.freeze()
> but not platform_driver.suspend. we have no pm.freeze() for pwm_bl, so
> the lcd black screen will disappear.
>
> Signed-off-by: Xiangzhen Ye <Xiangzhen.Ye at csr.com>
> Signed-off-by: Barry Song <Baohua.Song at csr.com>

Acked-by: Eric Miao <eric.y.miao at gmail.com>

> ---
>  drivers/video/backlight/pwm_bl.c |   15 ++++++++++-----
>  1 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
> index 8b5b2a4..50f3134 100644
> --- a/drivers/video/backlight/pwm_bl.c
> +++ b/drivers/video/backlight/pwm_bl.c
> @@ -169,9 +169,9 @@ static int pwm_backlight_remove(struct platform_device *pdev)
>  }
>
>  #ifdef CONFIG_PM
> -static int pwm_backlight_suspend(struct platform_device *pdev,
> -                                pm_message_t state)
> +static int pwm_backlight_suspend(struct device *dev)
>  {
> +       struct platform_device *pdev = to_platform_device(dev);
>        struct backlight_device *bl = platform_get_drvdata(pdev);
>        struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev);
>
> @@ -184,8 +184,9 @@ static int pwm_backlight_suspend(struct platform_device *pdev,
>        return 0;
>  }
>
> -static int pwm_backlight_resume(struct platform_device *pdev)
> +static int pwm_backlight_resume(struct device *dev)
>  {
> +       struct platform_device *pdev = to_platform_device(dev);
>        struct backlight_device *bl = platform_get_drvdata(pdev);
>
>        backlight_update_status(bl);
> @@ -196,15 +197,19 @@ static int pwm_backlight_resume(struct platform_device *pdev)
>  #define pwm_backlight_resume   NULL
>  #endif
>
> +static const struct dev_pm_ops pwm_backlight_pm_ops = {
> +       .suspend = pwm_backlight_suspend,
> +       .resume = pwm_backlight_resume,
> +};
> +
>  static struct platform_driver pwm_backlight_driver = {
>        .driver         = {
>                .name   = "pwm-backlight",
>                .owner  = THIS_MODULE,
> +               .pm     = &pwm_backlight_pm_ops,
>        },
>        .probe          = pwm_backlight_probe,
>        .remove         = pwm_backlight_remove,
> -       .suspend        = pwm_backlight_suspend,
> -       .resume         = pwm_backlight_resume,
>  };
>
>  static int __init pwm_backlight_init(void)
> --
> 1.7.1
>
>
>
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