Re: [PATCH v2] davinci: vpif: add pm_runtime support

[Hans Verkuil <hverkuil@xs4all.nl>]

On Mon 1 April 2013 08:36:50 Prabhakar lad wrote:
> From: Lad, Prabhakar <prabhakar.csengg@gmail.com>
> 
> Add pm_runtime support to the TI Davinci VPIF driver.
> 
> Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
> Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
> Cc: Hans Verkuil <hans.verkuil@cisco.com>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Sakari Ailus <sakari.ailus@iki.fi>
> Cc: Sekhar Nori <nsekhar@ti.com>
> ---
>  Changes for v2:
>  1: Removed use of clk API as pointed by Laurent and Sekhar.
> 
>  drivers/media/platform/davinci/vpif.c |   24 +++++++-----------------
>  1 files changed, 7 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/media/platform/davinci/vpif.c b/drivers/media/platform/davinci/vpif.c
> index 28638a8..599cabb 100644
> --- a/drivers/media/platform/davinci/vpif.c
> +++ b/drivers/media/platform/davinci/vpif.c
> @@ -23,8 +23,8 @@
>  #include <linux/spinlock.h>
>  #include <linux/kernel.h>
>  #include <linux/io.h>
> -#include <linux/clk.h>
>  #include <linux/err.h>
> +#include <linux/pm_runtime.h>
>  #include <linux/v4l2-dv-timings.h>
>  
>  #include <mach/hardware.h>
> @@ -44,7 +44,6 @@ static struct resource	*res;
>  spinlock_t vpif_lock;
>  
>  void __iomem *vpif_base;
> -struct clk *vpif_clk;
>  
>  /**
>   * ch_params: video standard configuration parameters for vpif
> @@ -439,19 +438,15 @@ static int vpif_probe(struct platform_device *pdev)
>  		goto fail;
>  	}
>  
> -	vpif_clk = clk_get(&pdev->dev, "vpif");
> -	if (IS_ERR(vpif_clk)) {
> -		status = PTR_ERR(vpif_clk);
> -		goto clk_fail;
> -	}
> -	clk_prepare_enable(vpif_clk);
> +	pm_runtime_enable(&pdev->dev);
> +	pm_runtime_resume(&pdev->dev);
> +
> +	pm_runtime_get(&pdev->dev);

pm_runtime_get() calls pm_runtime_resume() if needed, so is the call to resume()
really necessary?

Regards,

	Hans

>  
>  	spin_lock_init(&vpif_lock);
>  	dev_info(&pdev->dev, "vpif probe success\n");
>  	return 0;
>  
> -clk_fail:
> -	iounmap(vpif_base);
>  fail:
>  	release_mem_region(res->start, res_len);
>  	return status;
> @@ -459,11 +454,6 @@ fail:
>  
>  static int vpif_remove(struct platform_device *pdev)
>  {
> -	if (vpif_clk) {
> -		clk_disable_unprepare(vpif_clk);
> -		clk_put(vpif_clk);
> -	}
> -
>  	iounmap(vpif_base);
>  	release_mem_region(res->start, res_len);
>  	return 0;
> @@ -472,13 +462,13 @@ static int vpif_remove(struct platform_device *pdev)
>  #ifdef CONFIG_PM
>  static int vpif_suspend(struct device *dev)
>  {
> -	clk_disable_unprepare(vpif_clk);
> +	pm_runtime_put(dev);
>  	return 0;
>  }
>  
>  static int vpif_resume(struct device *dev)
>  {
> -	clk_prepare_enable(vpif_clk);
> +	pm_runtime_get(dev);
>  	return 0;
>  }
>  
>