Unverified Commit 47c08262 authored by Maxime Ripard's avatar Maxime Ripard
Browse files

drm/panel: panel-simple: Add function to look panel data up 



Commit de04bb00 ("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: default avatarFrancesco Dolcini <francesco@dolcini.it>
Closes: https://lore.kernel.org/all/20250612081834.GA248237@francesco-nb/


Fixes: de04bb00 ("drm/panel/panel-simple: Use the new allocation in place of devm_kzalloc()")
Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Tested-by: Francesco Dolcini <francesco.dolcini@toradex.com> # Toradex Colibri iMX6
Link: https://lore.kernel.org/r/20250626-drm-panel-simple-fixes-v2-4-5afcaa608bdc@kernel.org


Signed-off-by: default avatarMaxime Ripard <mripard@kernel.org>
parent 921c41e5

drivers/gpu/drm/panel/panel-simple.c

+49 −33
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <linux/i2c.h>

#include <linux/media-bus-format.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/of_platform.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>
@@ -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))

	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);