Re: [PATCH 7/8] drm/panel: himax-hx83102: Check for errors on the NOP in prepare()

[Dmitry Baryshkov]

On Fri, May 17, 2024 at 02:36:42PM -0700, Douglas Anderson wrote:
> The mipi_dsi_dcs_nop() function returns an error but we weren't
> checking it in hx83102_prepare(). Add a check. This is highly unlikely
> to matter in practice. If the NOP failed then likely later MIPI
> commands would fail too.
> 
> Found by code inspection.
> 
> Fixes: 0ef94554dc40 ("drm/panel: himax-hx83102: Break out as separate driver")
> Signed-off-by: Douglas Anderson 
> ---
> 
>  drivers/gpu/drm/panel/panel-himax-hx83102.c | 6 +-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 

Reviewed-by: Dmitry Baryshkov 

-- 
With best wishes
Dmitry

[PATCH 7/8] drm/panel: himax-hx83102: Check for errors on the NOP in prepare()

[Douglas Anderson]

The mipi_dsi_dcs_nop() function returns an error but we weren't
checking it in hx83102_prepare(). Add a check. This is highly unlikely
to matter in practice. If the NOP failed then likely later MIPI
commands would fail too.

Found by code inspection.

Fixes: 0ef94554dc40 ("drm/panel: himax-hx83102: Break out as separate driver")
Signed-off-by: Douglas Anderson 
---

 drivers/gpu/drm/panel/panel-himax-hx83102.c | 6 +-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/panel/panel-himax-hx83102.c 
b/drivers/gpu/drm/panel/panel-himax-hx83102.c
index 4ac7f9d8b232..1ba623e41924 100644
--- a/drivers/gpu/drm/panel/panel-himax-hx83102.c
+++ b/drivers/gpu/drm/panel/panel-himax-hx83102.c
@@ -547,7 +547,11 @@ static int hx83102_prepare(struct drm_panel *panel)
 
usleep_range(1, 11000);
 
-   mipi_dsi_dcs_nop(ctx->dsi);
+   ret = mipi_dsi_dcs_nop(ctx->dsi);
+   if (ret < 0) {
+   dev_err(dev, "Failed to send NOP: %d\n", ret);
+   goto poweroff;
+   }
usleep_range(1000, 2000);
 
gpiod_set_value(ctx->enable_gpio, 1);
-- 
2.45.0.rc1.225.g2a3ae87e7f-goog