[PATCH] drm/tilcdc: restore correct display mode and contents on pm resume

[PATCH] drm/tilcdc: restore correct display mode and contents on pm resume

[Felipe Balbi]

From: Darren Etheridge <detheridge@ti.com>

On resume the screen contents were not being restored properly.  Looking at
other DRM drivers it seems a call to drm_helper_resume_force_mode() is needed
in the resume handler to force restoration of the mode and framebuffer data.

Signed-off-by: Darren Etheridge <detheridge@ti.com>
---
 drivers/gpu/drm/tilcdc/tilcdc_drv.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
index 171a820..1a5ddfa 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
@@ -563,6 +563,13 @@ static int tilcdc_pm_resume(struct device *dev)
 		if (registers[i].save && (priv->rev >= registers[i].rev))
 			tilcdc_write(ddev, registers[i].reg, priv->saved_register[n++]);
 
+	/*
+	 * if this call isn't here, the display is blank on return from
+	 * suspend.  With this call here the contents of the framebuffer
+	 * during suspend are restored correctly.
+	 */
+	drm_helper_resume_force_mode(ddev);
+
 	drm_kms_helper_poll_enable(ddev);
 
 	return 0;
-- 
1.9.0

Re: [PATCH] drm/tilcdc: restore correct display mode and contents on pm resume

[Felipe Balbi]

[-- Attachment #1: Type: text/plain, Size: 1549 bytes --]

On Mon, Mar 03, 2014 at 01:08:56PM -0600, Felipe Balbi wrote:
> From: Darren Etheridge <detheridge@ti.com>
> 
> On resume the screen contents were not being restored properly.  Looking at
> other DRM drivers it seems a call to drm_helper_resume_force_mode() is needed
> in the resume handler to force restoration of the mode and framebuffer data.
> 
> Signed-off-by: Darren Etheridge <detheridge@ti.com>

ping

> ---
>  drivers/gpu/drm/tilcdc/tilcdc_drv.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> index 171a820..1a5ddfa 100644
> --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> @@ -563,6 +563,13 @@ static int tilcdc_pm_resume(struct device *dev)
>  		if (registers[i].save && (priv->rev >= registers[i].rev))
>  			tilcdc_write(ddev, registers[i].reg, priv->saved_register[n++]);
>  
> +	/*
> +	 * if this call isn't here, the display is blank on return from
> +	 * suspend.  With this call here the contents of the framebuffer
> +	 * during suspend are restored correctly.
> +	 */
> +	drm_helper_resume_force_mode(ddev);
> +
>  	drm_kms_helper_poll_enable(ddev);
>  
>  	return 0;
> -- 
> 1.9.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

-- 
balbi

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

Re: [PATCH] drm/tilcdc: restore correct display mode and contents on pm resume

[Rob Clark]

On Mon, Mar 3, 2014 at 2:08 PM, Felipe Balbi <balbi@ti.com> wrote:
> From: Darren Etheridge <detheridge@ti.com>
>
> On resume the screen contents were not being restored properly.  Looking at
> other DRM drivers it seems a call to drm_helper_resume_force_mode() is needed
> in the resume handler to force restoration of the mode and framebuffer data.
>
> Signed-off-by: Darren Etheridge <detheridge@ti.com>

Reviewed-by: Rob Clark <robdclark@gmail.com>

> ---
>  drivers/gpu/drm/tilcdc/tilcdc_drv.c | 7 +++++++
>  1 file changed, 7 insertions(+)
>
> diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> index 171a820..1a5ddfa 100644
> --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> @@ -563,6 +563,13 @@ static int tilcdc_pm_resume(struct device *dev)
>                 if (registers[i].save && (priv->rev >= registers[i].rev))
>                         tilcdc_write(ddev, registers[i].reg, priv->saved_register[n++]);
>
> +       /*
> +        * if this call isn't here, the display is blank on return from
> +        * suspend.  With this call here the contents of the framebuffer
> +        * during suspend are restored correctly.
> +        */
> +       drm_helper_resume_force_mode(ddev);
> +
>         drm_kms_helper_poll_enable(ddev);
>
>         return 0;
> --
> 1.9.0
>