From b430ff7ef8b016abcd8ebf8991920deb8750e351 Mon Sep 17 00:00:00 2001 From: Yannick Fertre Date: Fri, 28 Feb 2020 09:07:38 +0100 Subject: [PATCH] drm/stm: ltdc: check number of endpoints Number of endpoints could exceed the fix value MAX_ENDPOINTS(2). Instead of increase simply this value, the number of endpoint could be read from device tree. Load sequence has been a little rework to take care of several panel or bridge which can be connected/disconnected or enable/disable. Signed-off-by: Yannick Fertre Signed-off-by: Benjamin Gaignard Link: https://patchwork.freedesktop.org/patch/msgid/1582877258-1112-1-git-send-email-yannick.fertre@st.com --- drivers/gpu/drm/stm/ltdc.c | 102 +++++++++++++++++++------------------ 1 file changed, 52 insertions(+), 50 deletions(-) diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index df585fe64f61..f894968d6e45 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -42,8 +42,6 @@ #define MAX_IRQ 4 -#define MAX_ENDPOINTS 2 - #define HWVER_10200 0x010200 #define HWVER_10300 0x010300 #define HWVER_20101 0x020101 @@ -1201,36 +1199,20 @@ int ltdc_load(struct drm_device *ddev) struct ltdc_device *ldev = ddev->dev_private; struct device *dev = ddev->dev; struct device_node *np = dev->of_node; - struct drm_bridge *bridge[MAX_ENDPOINTS] = {NULL}; - struct drm_panel *panel[MAX_ENDPOINTS] = {NULL}; + struct drm_bridge *bridge; + struct drm_panel *panel; struct drm_crtc *crtc; struct reset_control *rstc; struct resource *res; - int irq, ret, i, endpoint_not_ready = -ENODEV; + int irq, i, nb_endpoints; + int ret = -ENODEV; DRM_DEBUG_DRIVER("\n"); - /* Get endpoints if any */ - for (i = 0; i < MAX_ENDPOINTS; i++) { - ret = drm_of_find_panel_or_bridge(np, 0, i, &panel[i], - &bridge[i]); - - /* - * If at least one endpoint is -EPROBE_DEFER, defer probing, - * else if at least one endpoint is ready, continue probing. - */ - if (ret == -EPROBE_DEFER) - return ret; - else if (!ret) - endpoint_not_ready = 0; - } - - if (endpoint_not_ready) - return endpoint_not_ready; - - rstc = devm_reset_control_get_exclusive(dev, NULL); - - mutex_init(&ldev->err_lock); + /* Get number of endpoints */ + nb_endpoints = of_graph_get_endpoint_count(np); + if (!nb_endpoints) + return -ENODEV; ldev->pixel_clk = devm_clk_get(dev, "lcd"); if (IS_ERR(ldev->pixel_clk)) { @@ -1244,6 +1226,43 @@ int ltdc_load(struct drm_device *ddev) return -ENODEV; } + /* Get endpoints if any */ + for (i = 0; i < nb_endpoints; i++) { + ret = drm_of_find_panel_or_bridge(np, 0, i, &panel, &bridge); + + /* + * If at least one endpoint is -ENODEV, continue probing, + * else if at least one endpoint returned an error + * (ie -EPROBE_DEFER) then stop probing. + */ + if (ret == -ENODEV) + continue; + else if (ret) + goto err; + + if (panel) { + bridge = drm_panel_bridge_add_typed(panel, + DRM_MODE_CONNECTOR_DPI); + if (IS_ERR(bridge)) { + DRM_ERROR("panel-bridge endpoint %d\n", i); + ret = PTR_ERR(bridge); + goto err; + } + } + + if (bridge) { + ret = ltdc_encoder_init(ddev, bridge); + if (ret) { + DRM_ERROR("init encoder endpoint %d\n", i); + goto err; + } + } + } + + rstc = devm_reset_control_get_exclusive(dev, NULL); + + mutex_init(&ldev->err_lock); + if (!IS_ERR(rstc)) { reset_control_assert(rstc); usleep_range(10, 20); @@ -1285,27 +1304,7 @@ int ltdc_load(struct drm_device *ddev) DRM_ERROR("Failed to register LTDC interrupt\n"); goto err; } - } - /* Add endpoints panels or bridges if any */ - for (i = 0; i < MAX_ENDPOINTS; i++) { - if (panel[i]) { - bridge[i] = drm_panel_bridge_add_typed(panel[i], - DRM_MODE_CONNECTOR_DPI); - if (IS_ERR(bridge[i])) { - DRM_ERROR("panel-bridge endpoint %d\n", i); - ret = PTR_ERR(bridge[i]); - goto err; - } - } - - if (bridge[i]) { - ret = ltdc_encoder_init(ddev, bridge[i]); - if (ret) { - DRM_ERROR("init encoder endpoint %d\n", i); - goto err; - } - } } crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL); @@ -1340,8 +1339,8 @@ int ltdc_load(struct drm_device *ddev) return 0; err: - for (i = 0; i < MAX_ENDPOINTS; i++) - drm_panel_bridge_remove(bridge[i]); + for (i = 0; i < nb_endpoints; i++) + drm_of_panel_bridge_remove(ddev->dev->of_node, 0, i); clk_disable_unprepare(ldev->pixel_clk); @@ -1350,11 +1349,14 @@ int ltdc_load(struct drm_device *ddev) void ltdc_unload(struct drm_device *ddev) { - int i; + struct device *dev = ddev->dev; + int nb_endpoints, i; DRM_DEBUG_DRIVER("\n"); - for (i = 0; i < MAX_ENDPOINTS; i++) + nb_endpoints = of_graph_get_endpoint_count(dev->of_node); + + for (i = 0; i < nb_endpoints; i++) drm_of_panel_bridge_remove(ddev->dev->of_node, 0, i); pm_runtime_disable(ddev->dev);