Right now, the DRM panel logic returns NULL when a panel pointing to the passed OF node is not present in the list of registered panels.
Most drivers interpret this NULL value as -EPROBE_DEFER, but we are about to modify the semantic of of_drm_find_panel() and let the framework return -ENODEV when the device node we're pointing to has a status property that is not equal to "okay" or "ok".
Let's first patch the of_drm_find_panel() implementation to return ERR_PTR(-EPROBE_DEFER) instead of NULL and patch all callers to replace the '!panel' check by an 'IS_ERR(panel)' one.
Signed-off-by: Boris Brezillon boris.brezillon@bootlin.com --- Changes in v3: - Rework error handling in a few drivers as suggested by Thierry - Return -ENODEV when CONFIG_OF or CONFIG_DRM_PANEL are not enabled
Changes in v2: - New commit --- drivers/gpu/drm/bridge/cdns-dsi.c | 2 +- drivers/gpu/drm/bridge/lvds-encoder.c | 4 ++-- drivers/gpu/drm/drm_of.c | 4 +++- drivers/gpu/drm/drm_panel.c | 6 ++++-- drivers/gpu/drm/exynos/exynos_dp.c | 6 ++++-- drivers/gpu/drm/exynos/exynos_drm_dpi.c | 4 ++-- drivers/gpu/drm/exynos/exynos_drm_dsi.c | 3 +++ drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 5 +++-- drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c | 4 ++-- drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c | 5 ++++- drivers/gpu/drm/msm/dsi/dsi_host.c | 2 +- drivers/gpu/drm/rcar-du/rcar_lvds.c | 4 ++-- drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 2 +- drivers/gpu/drm/sti/sti_dvo.c | 4 +++- drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 4 ++-- drivers/gpu/drm/tegra/dsi.c | 3 +++ drivers/gpu/drm/tegra/output.c | 4 ++-- include/drm/drm_panel.h | 2 +- 18 files changed, 43 insertions(+), 25 deletions(-)
diff --git a/drivers/gpu/drm/bridge/cdns-dsi.c b/drivers/gpu/drm/bridge/cdns-dsi.c index c255fc3e1be5..2c5991cf5397 100644 --- a/drivers/gpu/drm/bridge/cdns-dsi.c +++ b/drivers/gpu/drm/bridge/cdns-dsi.c @@ -1152,7 +1152,7 @@ static int cdns_dsi_attach(struct mipi_dsi_host *host, np = of_node_get(dev->dev.of_node);
panel = of_drm_find_panel(np); - if (panel) { + if (!IS_ERR(panel)) { bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DSI); } else { bridge = of_drm_find_bridge(dev->dev.of_node); diff --git a/drivers/gpu/drm/bridge/lvds-encoder.c b/drivers/gpu/drm/bridge/lvds-encoder.c index 75b0d3f6e4de..f56c92f7af7c 100644 --- a/drivers/gpu/drm/bridge/lvds-encoder.c +++ b/drivers/gpu/drm/bridge/lvds-encoder.c @@ -68,9 +68,9 @@ static int lvds_encoder_probe(struct platform_device *pdev)
panel = of_drm_find_panel(panel_node); of_node_put(panel_node); - if (!panel) { + if (IS_ERR(panel)) { dev_dbg(&pdev->dev, "panel not found, deferring probe\n"); - return -EPROBE_DEFER; + return PTR_ERR(panel); }
lvds_encoder->panel_bridge = diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c index 1fe122461298..81d3f76c43f3 100644 --- a/drivers/gpu/drm/drm_of.c +++ b/drivers/gpu/drm/drm_of.c @@ -240,8 +240,10 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
if (panel) { *panel = of_drm_find_panel(remote); - if (*panel) + if (!IS_ERR(*panel)) ret = 0; + else + *panel = NULL; }
/* No panel found yet, check for a bridge next. */ diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index 308d442a531b..49642d79df8f 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -135,7 +135,9 @@ EXPORT_SYMBOL(drm_panel_detach); * tree node. If a matching panel is found, return a pointer to it. * * Return: A pointer to the panel registered for the specified device tree - * node or NULL if no panel matching the device tree node can be found. + * node or an ERR_PTR() if no panel matching the device tree node can be found. + * The only error that can be reported is -EPROBE_DEFER, meaning that the panel + * device has not been probed yet, and the caller should retry later. */ struct drm_panel *of_drm_find_panel(const struct device_node *np) { @@ -151,7 +153,7 @@ struct drm_panel *of_drm_find_panel(const struct device_node *np) }
mutex_unlock(&panel_lock); - return NULL; + return ERR_PTR(-EPROBE_DEFER); } EXPORT_SYMBOL(of_drm_find_panel); #endif diff --git a/drivers/gpu/drm/exynos/exynos_dp.c b/drivers/gpu/drm/exynos/exynos_dp.c index 86330f396784..af7ab1ceb50f 100644 --- a/drivers/gpu/drm/exynos/exynos_dp.c +++ b/drivers/gpu/drm/exynos/exynos_dp.c @@ -232,9 +232,11 @@ static int exynos_dp_probe(struct platform_device *pdev) np = of_parse_phandle(dev->of_node, "panel", 0); if (np) { dp->plat_data.panel = of_drm_find_panel(np); + of_node_put(np); - if (!dp->plat_data.panel) - return -EPROBE_DEFER; + if (IS_ERR(dp->plat_data.panel)) + return PTR_ERR(dp->plat_data.panel); + goto out; }
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dpi.c b/drivers/gpu/drm/exynos/exynos_drm_dpi.c index 66945e0dc57f..5887e8522b70 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dpi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dpi.c @@ -240,8 +240,8 @@ struct drm_encoder *exynos_dpi_probe(struct device *dev)
if (ctx->panel_node) { ctx->panel = of_drm_find_panel(ctx->panel_node); - if (!ctx->panel) - return ERR_PTR(-EPROBE_DEFER); + if (IS_ERR(ctx->panel)) + return ERR_CAST(ctx->panel); }
return &ctx->encoder; diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c index 7904ffa9abfb..27d40da77181 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c @@ -1539,6 +1539,9 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host *host, dsi->format = device->format; dsi->mode_flags = device->mode_flags; dsi->panel = of_drm_find_panel(device->dev.of_node); + if (IS_ERR(dsi->panel)) + dsi->panel = NULL; + if (dsi->panel) { drm_panel_attach(dsi->panel, &dsi->connector); dsi->connector.status = connector_status_connected; diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c index c54806d08dd7..681e2a07d03b 100644 --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c @@ -148,8 +148,9 @@ int fsl_dcu_create_outputs(struct fsl_dcu_drm_device *fsl_dev) if (panel_node) { fsl_dev->connector.panel = of_drm_find_panel(panel_node); of_node_put(panel_node); - if (!fsl_dev->connector.panel) - return -EPROBE_DEFER; + if (IS_ERR(fsl_dev->connector.panel)) + return PTR_ERR(fsl_dev->connector.panel); + return fsl_dcu_attach_panel(fsl_dev, fsl_dev->connector.panel); }
diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c index 4a645926edb7..2bfb39082f54 100644 --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c @@ -341,7 +341,7 @@ static void mdp4_lcdc_encoder_disable(struct drm_encoder *encoder) mdp4_write(mdp4_kms, REG_MDP4_LCDC_ENABLE, 0);
panel = of_drm_find_panel(mdp4_lcdc_encoder->panel_node); - if (panel) { + if (!IS_ERR(panel)) { drm_panel_disable(panel); drm_panel_unprepare(panel); } @@ -410,7 +410,7 @@ static void mdp4_lcdc_encoder_enable(struct drm_encoder *encoder) dev_err(dev->dev, "failed to enable lcdc_clk: %d\n", ret);
panel = of_drm_find_panel(mdp4_lcdc_encoder->panel_node); - if (panel) { + if (!IS_ERR(panel)) { drm_panel_prepare(panel); drm_panel_enable(panel); } diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c index e3b1c86b7aae..32fba5664b0e 100644 --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c @@ -34,9 +34,12 @@ static enum drm_connector_status mdp4_lvds_connector_detect( struct mdp4_lvds_connector *mdp4_lvds_connector = to_mdp4_lvds_connector(connector);
- if (!mdp4_lvds_connector->panel) + if (!mdp4_lvds_connector->panel) { mdp4_lvds_connector->panel = of_drm_find_panel(mdp4_lvds_connector->panel_node); + if (IS_ERR(mdp4_lvds_connector->panel)) + mdp4_lvds_connector->panel = NULL; + }
return mdp4_lvds_connector->panel ? connector_status_connected : diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index 7a03a9489708..fffc80b73966 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -1881,7 +1881,7 @@ int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer) * output */ if (check_defer && msm_host->device_node) { - if (!of_drm_find_panel(msm_host->device_node)) + if (IS_ERR(of_drm_find_panel(msm_host->device_node))) if (!of_drm_find_bridge(msm_host->device_node)) return -EPROBE_DEFER; } diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c b/drivers/gpu/drm/rcar-du/rcar_lvds.c index 3d2d3bbd1342..ce7fb00909c4 100644 --- a/drivers/gpu/drm/rcar-du/rcar_lvds.c +++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c @@ -431,8 +431,8 @@ static int rcar_lvds_parse_dt(struct rcar_lvds *lvds) ret = -EPROBE_DEFER; } else { lvds->panel = of_drm_find_panel(remote); - if (!lvds->panel) - ret = -EPROBE_DEFER; + if (IS_ERR(lvds->panel)) + ret = PTR_ERR(lvds->panel); }
done: diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c index d53d5a09547f..01642aaf6127 100644 --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c @@ -595,7 +595,7 @@ static int dw_mipi_dsi_host_attach(struct mipi_dsi_host *host, dsi->format = device->format; dsi->mode_flags = device->mode_flags; dsi->panel = of_drm_find_panel(device->dev.of_node); - if (dsi->panel) + if (!IS_ERR(dsi->panel)) return drm_panel_attach(dsi->panel, &dsi->connector);
return -EINVAL; diff --git a/drivers/gpu/drm/sti/sti_dvo.c b/drivers/gpu/drm/sti/sti_dvo.c index a5979cd25cc7..030da55a8d30 100644 --- a/drivers/gpu/drm/sti/sti_dvo.c +++ b/drivers/gpu/drm/sti/sti_dvo.c @@ -387,7 +387,9 @@ sti_dvo_connector_detect(struct drm_connector *connector, bool force)
if (!dvo->panel) { dvo->panel = of_drm_find_panel(dvo->panel_node); - if (dvo->panel) + if (IS_ERR(dvo->panel)) + dvo->panel = NULL; + else drm_panel_attach(dvo->panel, connector); }
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c index bfbf761f0c1d..ce388d7cebaa 100644 --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c @@ -812,8 +812,8 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host,
dsi->device = device; dsi->panel = of_drm_find_panel(device->dev.of_node); - if (!dsi->panel) - return -EINVAL; + if (IS_ERR(dsi->panel)) + return PTR_ERR(dsi->panel);
dev_info(host->dev, "Attached device %s\n", device->name);
diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c index 87c5d89bc9ba..ad88ec230329 100644 --- a/drivers/gpu/drm/tegra/dsi.c +++ b/drivers/gpu/drm/tegra/dsi.c @@ -1411,6 +1411,9 @@ static int tegra_dsi_host_attach(struct mipi_dsi_host *host, struct tegra_output *output = &dsi->output;
output->panel = of_drm_find_panel(device->dev.of_node); + if (IS_ERR(output->panel)) + output->panel = NULL; + if (output->panel && output->connector.dev) { drm_panel_attach(output->panel, &output->connector); drm_helper_hpd_irq_event(output->connector.dev); diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c index 676fd394836f..c8e3cd633b5a 100644 --- a/drivers/gpu/drm/tegra/output.c +++ b/drivers/gpu/drm/tegra/output.c @@ -111,8 +111,8 @@ int tegra_output_probe(struct tegra_output *output) if (panel) { output->panel = of_drm_find_panel(panel); of_node_put(panel); - if (!output->panel) - return -EPROBE_DEFER; + if (IS_ERR(output->panel)) + return PTR_ERR(output->panel); }
output->edid = of_get_property(output->of_node, "nvidia,edid", &size); diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h index 14ac240a1f64..777814755fa6 100644 --- a/include/drm/drm_panel.h +++ b/include/drm/drm_panel.h @@ -199,7 +199,7 @@ struct drm_panel *of_drm_find_panel(const struct device_node *np); #else static inline struct drm_panel *of_drm_find_panel(const struct device_node *np) { - return NULL; + return ERR_PTR(-ENODEV); } #endif