From: Samuel Holland samuel@sholland.org
[ Upstream commit 0e4e3fb4901d19f49e5c0a582f383b10dda8d1c5 ]
The continued use of an ERR_PTR to signify "no panel" outside of sun6i_dsi_attach is confusing because it is a double negative. Because the connector always reports itself as connected, there is also the possibility of sending an ERR_PTR to drm_panel_get_modes(), which would crash.
Solve both of these by only storing the panel pointer if it is valid.
Fixes: 133add5b5ad4 ("drm/sun4i: Add Allwinner A31 MIPI-DSI controller support") Signed-off-by: Samuel Holland samuel@sholland.org Signed-off-by: Maxime Ripard maxime@cerno.tech Link: https://patchwork.freedesktop.org/patch/msgid/20200211072858.30784-2-samuel@... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c index a75fcb1131724..9bd3c97ff3e68 100644 --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c @@ -749,7 +749,7 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) phy_configure(dsi->dphy, &opts); phy_power_on(dsi->dphy);
- if (!IS_ERR(dsi->panel)) + if (dsi->panel) drm_panel_prepare(dsi->panel);
/* @@ -764,7 +764,7 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder) * ordering on the panels I've tested it with, so I guess this * will do for now, until that IP is better understood. */ - if (!IS_ERR(dsi->panel)) + if (dsi->panel) drm_panel_enable(dsi->panel);
sun6i_dsi_start(dsi, DSI_START_HSC); @@ -780,7 +780,7 @@ static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder)
DRM_DEBUG_DRIVER("Disabling DSI output\n");
- if (!IS_ERR(dsi->panel)) { + if (dsi->panel) { drm_panel_disable(dsi->panel); drm_panel_unprepare(dsi->panel); } @@ -942,11 +942,13 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host, struct mipi_dsi_device *device) { struct sun6i_dsi *dsi = host_to_sun6i_dsi(host); + struct drm_panel *panel = of_drm_find_panel(device->dev.of_node);
+ if (IS_ERR(panel)) + return PTR_ERR(panel); + + dsi->panel = panel; dsi->device = device; - dsi->panel = of_drm_find_panel(device->dev.of_node); - if (IS_ERR(dsi->panel)) - return PTR_ERR(dsi->panel);
dev_info(host->dev, "Attached device %s\n", device->name);