Commit 280921de authored by Thierry Reding's avatar Thierry Reding
Browse files

drm/panel: Add simple panel support 



Add a driver for simple panels. Such panels can have a regulator that
provides the supply voltage and a separate GPIO to enable the panel.
Optionally the panels can have a backlight associated with them so it
can be enabled or disabled according to the panel's power management
mode.

Support is added for two panels: An AU Optronics 10.1" WSVGA and a
Chunghwa Picture Tubes 10.1" WXGA panel.

Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
parent aead40ea

drivers/gpu/drm/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -61,3 +61,4 @@ obj-$(CONFIG_DRM_QXL) += qxl/ 
obj-$(CONFIG_DRM_MSM) += msm/

obj-$(CONFIG_DRM_TEGRA) += tegra/

obj-y			+= i2c/

obj-y			+= panel/

drivers/gpu/drm/panel/Kconfig

+14 −0
Original line number Diff line number Diff line
@@ -3,3 +3,17 @@ config DRM_PANEL 
	depends on DRM

	help

	  Panel registration and lookup framework.



menu "Display Panels"

	depends on DRM_PANEL



config DRM_PANEL_SIMPLE

	tristate "support for simple panels"

	depends on OF

	help

	  DRM panel driver for dumb panels that need at most a regulator and

	  a GPIO to be powered up. Optionally a backlight can be attached so

	  that it can be automatically turned off when the panel goes into a

	  low power state.



endmenu

drivers/gpu/drm/panel/Makefile

0 → 100644
+1 −0
Original line number Diff line number Diff line 
obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o

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

0 → 100644
+417 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2013, NVIDIA Corporation.  All rights reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sub license,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice (including the

 * next paragraph) shall be included in all copies or substantial portions

 * of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

 * DEALINGS IN THE SOFTWARE.

 */



#include <linux/backlight.h>

#include <linux/gpio.h>

#include <linux/module.h>

#include <linux/of_gpio.h>

#include <linux/of_platform.h>

#include <linux/platform_device.h>

#include <linux/regulator/consumer.h>



#include <drm/drmP.h>

#include <drm/drm_crtc.h>

#include <drm/drm_panel.h>



struct panel_desc {

	const struct drm_display_mode *modes;

	unsigned int num_modes;



	struct {

		unsigned int width;

		unsigned int height;

	} size;

};



/* TODO: convert to gpiod_*() API once it's been merged */

#define GPIO_ACTIVE_LOW	(1 << 0)



struct panel_simple {

	struct drm_panel base;

	bool enabled;



	const struct panel_desc *desc;



	struct backlight_device *backlight;

	struct regulator *supply;

	struct i2c_adapter *ddc;



	unsigned long enable_gpio_flags;

	int enable_gpio;

};



static inline struct panel_simple *to_panel_simple(struct drm_panel *panel)

{

	return container_of(panel, struct panel_simple, base);

}



static int panel_simple_get_fixed_modes(struct panel_simple *panel)

{

	struct drm_connector *connector = panel->base.connector;

	struct drm_device *drm = panel->base.drm;

	struct drm_display_mode *mode;

	unsigned int i, num = 0;



	if (!panel->desc)

		return 0;



	for (i = 0; i < panel->desc->num_modes; i++) {

		const struct drm_display_mode *m = &panel->desc->modes[i];



		mode = drm_mode_duplicate(drm, m);

		if (!mode) {

			dev_err(drm->dev, "failed to add mode %ux%u@%u\n",

				m->hdisplay, m->vdisplay, m->vrefresh);

			continue;

		}



		drm_mode_set_name(mode);



		drm_mode_probed_add(connector, mode);

		num++;

	}



	connector->display_info.width_mm = panel->desc->size.width;

	connector->display_info.height_mm = panel->desc->size.height;



	return num;

}



static int panel_simple_disable(struct drm_panel *panel)

{

	struct panel_simple *p = to_panel_simple(panel);



	if (!p->enabled)

		return 0;



	if (p->backlight) {

		p->backlight->props.power = FB_BLANK_POWERDOWN;

		backlight_update_status(p->backlight);

	}



	if (gpio_is_valid(p->enable_gpio)) {

		if (p->enable_gpio_flags & GPIO_ACTIVE_LOW)

			gpio_set_value(p->enable_gpio, 1);

		else

			gpio_set_value(p->enable_gpio, 0);

	}



	regulator_disable(p->supply);

	p->enabled = false;



	return 0;

}



static int panel_simple_enable(struct drm_panel *panel)

{

	struct panel_simple *p = to_panel_simple(panel);

	int err;



	if (p->enabled)

		return 0;



	err = regulator_enable(p->supply);

	if (err < 0) {

		dev_err(panel->dev, "failed to enable supply: %d\n", err);

		return err;

	}



	if (gpio_is_valid(p->enable_gpio)) {

		if (p->enable_gpio_flags & GPIO_ACTIVE_LOW)

			gpio_set_value(p->enable_gpio, 0);

		else

			gpio_set_value(p->enable_gpio, 1);

	}



	if (p->backlight) {

		p->backlight->props.power = FB_BLANK_UNBLANK;

		backlight_update_status(p->backlight);

	}



	p->enabled = true;



	return 0;

}



static int panel_simple_get_modes(struct drm_panel *panel)

{

	struct panel_simple *p = to_panel_simple(panel);

	int num = 0;



	/* probe EDID if a DDC bus is available */

	if (p->ddc) {

		struct edid *edid = drm_get_edid(panel->connector, p->ddc);

		if (edid) {

			num += drm_add_edid_modes(panel->connector, edid);

			kfree(edid);

		}

	}



	/* add hard-coded panel modes */

	num += panel_simple_get_fixed_modes(p);



	return num;

}



static const struct drm_panel_funcs panel_simple_funcs = {

	.disable = panel_simple_disable,

	.enable = panel_simple_enable,

	.get_modes = panel_simple_get_modes,

};



static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)

{

	struct device_node *backlight, *ddc;

	struct panel_simple *panel;

	enum of_gpio_flags flags;

	int err;



	panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL);

	if (!panel)

		return -ENOMEM;



	panel->enabled = false;

	panel->desc = desc;



	panel->supply = devm_regulator_get(dev, "power");

	if (IS_ERR(panel->supply))

		return PTR_ERR(panel->supply);



	panel->enable_gpio = of_get_named_gpio_flags(dev->of_node,

						     "enable-gpios", 0,

						     &flags);

	if (gpio_is_valid(panel->enable_gpio)) {

		unsigned int value;



		if (flags & OF_GPIO_ACTIVE_LOW)

			panel->enable_gpio_flags |= GPIO_ACTIVE_LOW;



		err = gpio_request(panel->enable_gpio, "enable");

		if (err < 0) {

			dev_err(dev, "failed to request GPIO#%u: %d\n",

				panel->enable_gpio, err);

			return err;

		}



		value = (panel->enable_gpio_flags & GPIO_ACTIVE_LOW) != 0;



		err = gpio_direction_output(panel->enable_gpio, value);

		if (err < 0) {

			dev_err(dev, "failed to setup GPIO%u: %d\n",

				panel->enable_gpio, err);

			goto free_gpio;

		}

	}



	backlight = of_parse_phandle(dev->of_node, "backlight", 0);

	if (backlight) {

		panel->backlight = of_find_backlight_by_node(backlight);

		of_node_put(backlight);



		if (!panel->backlight) {

			err = -EPROBE_DEFER;

			goto free_gpio;

		}

	}



	ddc = of_parse_phandle(dev->of_node, "ddc-i2c-bus", 0);

	if (ddc) {

		panel->ddc = of_find_i2c_adapter_by_node(ddc);

		of_node_put(ddc);



		if (!panel->ddc) {

			err = -EPROBE_DEFER;

			goto free_backlight;

		}

	}



	drm_panel_init(&panel->base);

	panel->base.dev = dev;

	panel->base.funcs = &panel_simple_funcs;



	err = drm_panel_add(&panel->base);

	if (err < 0)

		goto free_ddc;



	dev_set_drvdata(dev, panel);



	return 0;



free_ddc:

	if (panel->ddc)

		put_device(&panel->ddc->dev);

free_backlight:

	if (panel->backlight)

		put_device(&panel->backlight->dev);

free_gpio:

	if (gpio_is_valid(panel->enable_gpio))

		gpio_free(panel->enable_gpio);



	return err;

}



static int panel_simple_remove(struct device *dev)

{

	struct panel_simple *panel = dev_get_drvdata(dev);



	drm_panel_detach(&panel->base);

	drm_panel_remove(&panel->base);



	panel_simple_disable(&panel->base);



	if (panel->ddc)

		put_device(&panel->ddc->dev);



	if (panel->backlight)

		put_device(&panel->backlight->dev);



	if (gpio_is_valid(panel->enable_gpio))

		gpio_free(panel->enable_gpio);



	regulator_disable(panel->supply);



	return 0;

}



static const struct drm_display_mode auo_b101aw03_mode = {

	.clock = 51450,

	.hdisplay = 1024,

	.hsync_start = 1024 + 156,

	.hsync_end = 1024 + 156 + 8,

	.htotal = 1024 + 156 + 8 + 156,

	.vdisplay = 600,

	.vsync_start = 600 + 16,

	.vsync_end = 600 + 16 + 6,

	.vtotal = 600 + 16 + 6 + 16,

	.vrefresh = 60,

};



static const struct panel_desc auo_b101aw03 = {

	.modes = &auo_b101aw03_mode,

	.num_modes = 1,

	.size = {

		.width = 223,

		.height = 125,

	},

};



static const struct drm_display_mode chunghwa_claa101wb01_mode = {

	.clock = 69300,

	.hdisplay = 1366,

	.hsync_start = 1366 + 48,

	.hsync_end = 1366 + 48 + 32,

	.htotal = 1366 + 48 + 32 + 20,

	.vdisplay = 768,

	.vsync_start = 768 + 16,

	.vsync_end = 768 + 16 + 8,

	.vtotal = 768 + 16 + 8 + 16,

	.vrefresh = 60,

};



static const struct panel_desc chunghwa_claa101wb01 = {

	.modes = &chunghwa_claa101wb01_mode,

	.num_modes = 1,

	.size = {

		.width = 223,

		.height = 125,

	},

};



static const struct of_device_id platform_of_match[] = {

	{

		.compatible = "auo,b101aw03",

		.data = &auo_b101aw03,

	}, {

		.compatible = "chunghwa,claa101wb01",

		.data = &chunghwa_claa101wb01

	}, {

		.compatible = "simple-panel",

	}, {

		/* sentinel */

	}

};

MODULE_DEVICE_TABLE(of, platform_of_match);



static int panel_simple_platform_probe(struct platform_device *pdev)

{

	const struct of_device_id *id;



	id = of_match_node(platform_of_match, pdev->dev.of_node);

	if (!id)

		return -ENODEV;



	return panel_simple_probe(&pdev->dev, id->data);

}



static int panel_simple_platform_remove(struct platform_device *pdev)

{

	return panel_simple_remove(&pdev->dev);

}



static struct platform_driver panel_simple_platform_driver = {

	.driver = {

		.name = "panel-simple",

		.owner = THIS_MODULE,

		.of_match_table = platform_of_match,

	},

	.probe = panel_simple_platform_probe,

	.remove = panel_simple_platform_remove,

};



static const struct drm_display_mode panasonic_vvx10f004b00_mode = {

	.clock = 157200,

	.hdisplay = 1920,

	.hsync_start = 1920 + 154,

	.hsync_end = 1920 + 154 + 16,

	.htotal = 1920 + 154 + 16 + 32,

	.vdisplay = 1200,

	.vsync_start = 1200 + 17,

	.vsync_end = 1200 + 17 + 2,

	.vtotal = 1200 + 17 + 2 + 16,

	.vrefresh = 60,

};



static const struct panel_desc panasonic_vvx10f004b00 = {

	.modes = &panasonic_vvx10f004b00_mode,

	.num_modes = 1,

	.size = {

		.width = 217,

		.height = 136,

	},

};



static int __init panel_simple_init(void)

{

	return platform_driver_register(&panel_simple_platform_driver);

}

module_init(panel_simple_init);



static void __exit panel_simple_exit(void)

{

	platform_driver_unregister(&panel_simple_platform_driver);

}

module_exit(panel_simple_exit);



MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");

MODULE_DESCRIPTION("DRM Driver for Simple Panels");

MODULE_LICENSE("GPL and additional rights");

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