5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Douglas Anderson <dianders@xxxxxxxxxxxx> [ Upstream commit 6320b9199dd99622668649c234d4e8a99e44a9c8 ] The mipi_dsi_dcs_nop() function returns an error but we weren't checking it in boe_panel_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: 812562b8d881 ("drm/panel: boe-tv101wum-nl6: Fine tune the panel power sequence") Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240517143643.3.Ibffbaa5b4999ac0e55f43bf353144433b099d727@changeid Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20240517143643.3.Ibffbaa5b4999ac0e55f43bf353144433b099d727@changeid Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c index c448be3d01d16..0a2d5f461aee8 100644 --- a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c +++ b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c @@ -553,7 +553,11 @@ static int boe_panel_prepare(struct drm_panel *panel) usleep_range(5000, 10000); if (boe->desc->lp11_before_reset) { - mipi_dsi_dcs_nop(boe->dsi); + ret = mipi_dsi_dcs_nop(boe->dsi); + if (ret < 0) { + dev_err(&boe->dsi->dev, "Failed to send NOP: %d\n", ret); + goto poweroff; + } usleep_range(1000, 2000); } gpiod_set_value(boe->enable_gpio, 1); -- 2.43.0