From 189723fbe9aca18d6f7d638c59a40288030932b5 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 13 Oct 2021 11:08:25 +0300 Subject: drm/bridge: display-connector: fix an uninitialized pointer in probe() The "label" pointer is used for debug output. The code assumes that it is either NULL or valid, but it is never set to NULL. It is either valid or uninitialized. Fixes: 0c275c30176b ("drm/bridge: Add bridge driver for display connectors") Signed-off-by: Dan Carpenter Signed-off-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20211013080825.GE6010@kili --- drivers/gpu/drm/bridge/display-connector.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/gpu/drm/bridge/display-connector.c') diff --git a/drivers/gpu/drm/bridge/display-connector.c b/drivers/gpu/drm/bridge/display-connector.c index 05eb759da6fc..847a0dce7f1d 100644 --- a/drivers/gpu/drm/bridge/display-connector.c +++ b/drivers/gpu/drm/bridge/display-connector.c @@ -107,7 +107,7 @@ static int display_connector_probe(struct platform_device *pdev) { struct display_connector *conn; unsigned int type; - const char *label; + const char *label = NULL; int ret; conn = devm_kzalloc(&pdev->dev, sizeof(*conn), GFP_KERNEL); -- cgit v1.2.3 From 7cd70656d1285b79c001f041a017fcfee4292ff9 Mon Sep 17 00:00:00 2001 From: Neil Armstrong Date: Wed, 20 Oct 2021 14:39:42 +0200 Subject: drm/bridge: display-connector: implement bus fmts callbacks Since this bridge is tied to the connector, it acts like a passthrough, so concerning the output & input bus formats, either pass the bus formats from the previous bridge or return fallback data like done in the bridge function: drm_atomic_bridge_chain_select_bus_fmts() & select_bus_fmt_recursive. This permits avoiding skipping the negociation if the remaining bridge chain has all the bits in place. Without this bus fmt negociation breaks on drm/meson HDMI pipeline when attaching dw-hdmi with DRM_BRIDGE_ATTACH_NO_CONNECTOR, because the last bridge of the display-connector doesn't implement buf fmt callbacks and MEDIA_BUS_FMT_FIXED is used leading to select an unsupported default bus format from dw-hdmi. Signed-off-by: Neil Armstrong Reviewed-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20211020123947.2585572-2-narmstrong@baylibre.com --- drivers/gpu/drm/bridge/display-connector.c | 86 ++++++++++++++++++++++++++++++ 1 file changed, 86 insertions(+) (limited to 'drivers/gpu/drm/bridge/display-connector.c') diff --git a/drivers/gpu/drm/bridge/display-connector.c b/drivers/gpu/drm/bridge/display-connector.c index 847a0dce7f1d..d24f5b90feab 100644 --- a/drivers/gpu/drm/bridge/display-connector.c +++ b/drivers/gpu/drm/bridge/display-connector.c @@ -13,6 +13,7 @@ #include #include +#include #include #include @@ -87,10 +88,95 @@ static struct edid *display_connector_get_edid(struct drm_bridge *bridge, return drm_get_edid(connector, conn->bridge.ddc); } +/* + * Since this bridge is tied to the connector, it acts like a passthrough, + * so concerning the output bus formats, either pass the bus formats from the + * previous bridge or return fallback data like done in the bridge function: + * drm_atomic_bridge_chain_select_bus_fmts(). + * This supports negotiation if the bridge chain has all bits in place. + */ +static u32 *display_connector_get_output_bus_fmts(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + unsigned int *num_output_fmts) +{ + struct drm_bridge *prev_bridge = drm_bridge_get_prev_bridge(bridge); + struct drm_bridge_state *prev_bridge_state; + + if (!prev_bridge || !prev_bridge->funcs->atomic_get_output_bus_fmts) { + struct drm_connector *conn = conn_state->connector; + u32 *out_bus_fmts; + + *num_output_fmts = 1; + out_bus_fmts = kmalloc(sizeof(*out_bus_fmts), GFP_KERNEL); + if (!out_bus_fmts) + return NULL; + + if (conn->display_info.num_bus_formats && + conn->display_info.bus_formats) + out_bus_fmts[0] = conn->display_info.bus_formats[0]; + else + out_bus_fmts[0] = MEDIA_BUS_FMT_FIXED; + + return out_bus_fmts; + } + + prev_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state, + prev_bridge); + + return prev_bridge->funcs->atomic_get_output_bus_fmts(prev_bridge, prev_bridge_state, + crtc_state, conn_state, + num_output_fmts); +} + +/* + * Since this bridge is tied to the connector, it acts like a passthrough, + * so concerning the input bus formats, either pass the bus formats from the + * previous bridge or MEDIA_BUS_FMT_FIXED (like select_bus_fmt_recursive()) + * when atomic_get_input_bus_fmts is not supported. + * This supports negotiation if the bridge chain has all bits in place. + */ +static u32 *display_connector_get_input_bus_fmts(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + u32 output_fmt, + unsigned int *num_input_fmts) +{ + struct drm_bridge *prev_bridge = drm_bridge_get_prev_bridge(bridge); + struct drm_bridge_state *prev_bridge_state; + + if (!prev_bridge || !prev_bridge->funcs->atomic_get_input_bus_fmts) { + u32 *in_bus_fmts; + + *num_input_fmts = 1; + in_bus_fmts = kmalloc(sizeof(*in_bus_fmts), GFP_KERNEL); + if (!in_bus_fmts) + return NULL; + + in_bus_fmts[0] = MEDIA_BUS_FMT_FIXED; + + return in_bus_fmts; + } + + prev_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state, + prev_bridge); + + return prev_bridge->funcs->atomic_get_input_bus_fmts(prev_bridge, prev_bridge_state, + crtc_state, conn_state, output_fmt, + num_input_fmts); +} + static const struct drm_bridge_funcs display_connector_bridge_funcs = { .attach = display_connector_attach, .detect = display_connector_detect, .get_edid = display_connector_get_edid, + .atomic_get_output_bus_fmts = display_connector_get_output_bus_fmts, + .atomic_get_input_bus_fmts = display_connector_get_input_bus_fmts, + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, + .atomic_reset = drm_atomic_helper_bridge_reset, }; static irqreturn_t display_connector_hpd_irq(int irq, void *arg) -- cgit v1.2.3