6.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Douglas Anderson <dianders@xxxxxxxxxxxx> [ Upstream commit 6a7bd6cde73f0fb7e5faa964dbdeb45b55c64698 ] The mipi_dsi_dcs_nop() function returns an error but we weren't checking it in ili9882t_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: e2450d32e5fb ("drm/panel: ili9882t: Break out as separate driver") Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240517143643.5.I323476ba9fa8cc7a5adee4c1ec95202785cc5686@changeid Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20240517143643.5.I323476ba9fa8cc7a5adee4c1ec95202785cc5686@changeid Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/panel/panel-ilitek-ili9882t.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panel/panel-ilitek-ili9882t.c b/drivers/gpu/drm/panel/panel-ilitek-ili9882t.c index 5762eba73955c..35ea5494e0eb8 100644 --- a/drivers/gpu/drm/panel/panel-ilitek-ili9882t.c +++ b/drivers/gpu/drm/panel/panel-ilitek-ili9882t.c @@ -560,7 +560,11 @@ static int ili9882t_prepare(struct drm_panel *panel) usleep_range(10000, 11000); // MIPI needs to keep the LP11 state before the lcm_reset pin is pulled high - mipi_dsi_dcs_nop(ili->dsi); + ret = mipi_dsi_dcs_nop(ili->dsi); + if (ret < 0) { + dev_err(&ili->dsi->dev, "Failed to send NOP: %d\n", ret); + goto poweroff; + } usleep_range(1000, 2000); gpiod_set_value(ili->enable_gpio, 1); -- 2.43.0