[PATCH v2 2/2] drm/rockchip: dw_hdmi: Handle suspend/resume

[PATCH v2 2/2] drm/rockchip: dw_hdmi: Handle suspend/resume

[Douglas Anderson]

On Rockchip rk3288-based Chromebooks when you do a suspend/resume
cycle:

1. You lose the ability to detect an HDMI device being plugged in.

2. If you're using the i2c bus built in to dw_hdmi then it stops
working.

Let's call the core dw-hdmi's suspend/resume functions to restore
things.

NOTE: in downstream Chrome OS (based on kernel 3.14) we used the
"late/early" versions of suspend/resume because we found that the VOP
was sometimes resuming before dw_hdmi and then calling into us before
we were fully resumed.  For now I have gone back to the normal
suspend/resume because I can't reproduce the problems.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
---

Changes in v2:
- Add forgotten static (Laurent)
- No empty stub for suspend (Laurent)

 drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
index 4cdc9f86c2e5..beffe44c248a 100644
--- a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
@@ -542,11 +542,23 @@ static int dw_hdmi_rockchip_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static int __maybe_unused dw_hdmi_rockchip_resume(struct device *dev)
+{
+	struct rockchip_hdmi *hdmi = dev_get_drvdata(dev);
+
+	return dw_hdmi_resume(hdmi->hdmi);
+}
+
+static const struct dev_pm_ops dw_hdmi_rockchip_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(NULL, dw_hdmi_rockchip_resume)
+};
+
 struct platform_driver dw_hdmi_rockchip_pltfm_driver = {
 	.probe  = dw_hdmi_rockchip_probe,
 	.remove = dw_hdmi_rockchip_remove,
 	.driver = {
 		.name = "dwhdmi-rockchip",
+		.pm = &dw_hdmi_rockchip_pm,
 		.of_match_table = dw_hdmi_rockchip_dt_ids,
 	},
 };
-- 
2.21.0.1020.gf2820cf01a-goog


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v2 2/2] drm/rockchip: dw_hdmi: Handle suspend/resume

[Doug Anderson]

Hi,

On Thu, May 16, 2019 at 2:40 PM Douglas Anderson <dianders@chromium.org> wrote:
>
> On Rockchip rk3288-based Chromebooks when you do a suspend/resume
> cycle:
>
> 1. You lose the ability to detect an HDMI device being plugged in.
>
> 2. If you're using the i2c bus built in to dw_hdmi then it stops
> working.
>
> Let's call the core dw-hdmi's suspend/resume functions to restore
> things.
>
> NOTE: in downstream Chrome OS (based on kernel 3.14) we used the
> "late/early" versions of suspend/resume because we found that the VOP
> was sometimes resuming before dw_hdmi and then calling into us before
> we were fully resumed.  For now I have gone back to the normal
> suspend/resume because I can't reproduce the problems.
>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
>
> Changes in v2:
> - Add forgotten static (Laurent)
> - No empty stub for suspend (Laurent)
>
>  drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)

Whoops, forgot that I should have carried forward:

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

-Doug

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel