From 47c08262f34e1cd9c48364431e4d32529029b910 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Thu, 26 Jun 2025 12:05:02 +0200 Subject: [PATCH] drm/panel: panel-simple: Add function to look panel data up Commit de04bb0089a9 ("drm/panel/panel-simple: Use the new allocation in place of devm_kzalloc()") moved the call to drm_panel_init into the devm_drm_panel_alloc(), which needs a connector type to initialize properly. In the panel-dpi compatible case, the passed panel_desc structure is an empty one used as a discriminant, and the connector type it contains isn't actually initialized. It is initialized through a call to panel_dpi_probe() later in the function, which used to be before the call to drm_panel_init() that got merged into devm_drm_panel_alloc(). So, we do need a proper panel_desc pointer before the call to devm_drm_panel_alloc() now. All cases associate their panel_desc with the panel compatible and use of_device_get_match_data, except for the panel-dpi compatible. In that case, we're expected to call panel_dpi_probe, which will allocate and initialize the panel_desc for us. Let's create such a helper function that would be called first in the driver and will lookup the desc by compatible, or allocate one if relevant. Reported-by: Francesco Dolcini Closes: https://lore.kernel.org/all/20250612081834.GA248237@francesco-nb/ Fixes: de04bb0089a9 ("drm/panel/panel-simple: Use the new allocation in place of devm_kzalloc()") Reviewed-by: Javier Martinez Canillas Tested-by: Francesco Dolcini # Toradex Colibri iMX6 Link: https://lore.kernel.org/r/20250626-drm-panel-simple-fixes-v2-4-5afcaa608bdc@kernel.org Signed-off-by: Maxime Ripard --- drivers/gpu/drm/panel/panel-simple.c | 82 +++++++++++++++++----------- 1 file changed, 49 insertions(+), 33 deletions(-) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index e70ee2d4a538..4c831af86414 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -136,6 +137,14 @@ struct panel_desc { int connector_type; }; +struct panel_desc_dsi { + struct panel_desc desc; + + unsigned long flags; + enum mipi_dsi_pixel_format format; + unsigned int lanes; +}; + struct panel_simple { struct drm_panel base; @@ -567,8 +576,38 @@ static int panel_simple_override_nondefault_lvds_datamapping(struct device *dev, return 0; } -static struct panel_simple *panel_simple_probe(struct device *dev, const struct panel_desc *desc) +static const struct panel_desc *panel_simple_get_desc(struct device *dev) +{ + if (IS_ENABLED(CONFIG_DRM_MIPI_DSI) && + dev_is_mipi_dsi(dev)) { + const struct panel_desc_dsi *dsi_desc; + + dsi_desc = of_device_get_match_data(dev); + if (!dsi_desc) + return ERR_PTR(-ENODEV); + + return &dsi_desc->desc; + } + + if (dev_is_platform(dev)) { + const struct panel_desc *desc; + + desc = of_device_get_match_data(dev); + if (!desc) + return ERR_PTR(-ENODEV); + + if (desc == &panel_dpi) + return panel_dpi_probe(dev); + + return desc; + } + + return ERR_PTR(-ENODEV); +} + +static struct panel_simple *panel_simple_probe(struct device *dev) { + const struct panel_desc *desc; struct panel_simple *panel; struct display_timing dt; struct device_node *ddc; @@ -576,6 +615,10 @@ static struct panel_simple *panel_simple_probe(struct device *dev, const struct u32 bus_flags; int err; + desc = panel_simple_get_desc(dev); + if (IS_ERR(desc)) + return ERR_CAST(desc); + panel = devm_drm_panel_alloc(dev, struct panel_simple, base, &panel_simple_funcs, desc->connector_type); if (IS_ERR(panel)) @@ -608,19 +651,9 @@ static struct panel_simple *panel_simple_probe(struct device *dev, const struct return ERR_PTR(-EPROBE_DEFER); } - if (desc == &panel_dpi) { - /* Handle the generic panel-dpi binding */ - desc = panel_dpi_probe(dev); - if (IS_ERR(desc)) { - err = PTR_ERR(desc); - goto free_ddc; - } - - panel->desc = desc; - } else { - if (!of_get_display_timing(dev->of_node, "panel-timing", &dt)) - panel_simple_parse_panel_timing_node(dev, panel, &dt); - } + if ((desc != &panel_dpi) && + !of_get_display_timing(dev->of_node, "panel-timing", &dt)) + panel_simple_parse_panel_timing_node(dev, panel, &dt); if (desc->connector_type == DRM_MODE_CONNECTOR_LVDS) { /* Optional data-mapping property for overriding bus format */ @@ -5376,14 +5409,9 @@ MODULE_DEVICE_TABLE(of, platform_of_match); static int panel_simple_platform_probe(struct platform_device *pdev) { - const struct panel_desc *desc; struct panel_simple *panel; - desc = of_device_get_match_data(&pdev->dev); - if (!desc) - return -ENODEV; - - panel = panel_simple_probe(&pdev->dev, desc); + panel = panel_simple_probe(&pdev->dev); if (IS_ERR(panel)) return PTR_ERR(panel); @@ -5417,14 +5445,6 @@ static struct platform_driver panel_simple_platform_driver = { .shutdown = panel_simple_platform_shutdown, }; -struct panel_desc_dsi { - struct panel_desc desc; - - unsigned long flags; - enum mipi_dsi_pixel_format format; - unsigned int lanes; -}; - static const struct drm_display_mode auo_b080uan01_mode = { .clock = 154500, .hdisplay = 1200, @@ -5661,11 +5681,7 @@ static int panel_simple_dsi_probe(struct mipi_dsi_device *dsi) struct panel_simple *panel; int err; - desc = of_device_get_match_data(&dsi->dev); - if (!desc) - return -ENODEV; - - panel = panel_simple_probe(&dsi->dev, &desc->desc); + panel = panel_simple_probe(&dsi->dev); if (IS_ERR(panel)) return PTR_ERR(panel); -- 2.25.1