diff mbox

[v2,22/27] drm/panel: Add simple panel support

Message ID 1381134884-5816-23-git-send-email-treding@nvidia.com
State Superseded
Headers show

Commit Message

Thierry Reding Oct. 7, 2013, 8:34 a.m. UTC
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 three panels: An AU Optronics 10.1" WSVGA, a
Chunghwa Picture Tubes 10.1" WXGA and a Panasonic 10.1 WUXGA TFT LCD
panel.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
Changes in v2:
- update vendor prefixes (cptt -> chunghwa, pc -> panasonic)
- split up panel binding documents per-panel
- make regulator mandatory
- add flag to keep track of enabled status

 .../devicetree/bindings/panel/auo,b101aw03.txt     |   7 +
 .../bindings/panel/chunghwa,claa101wb03.txt        |   7 +
 .../bindings/panel/panasonic,vvx10f004b00.txt      |   7 +
 .../devicetree/bindings/panel/simple-panel.txt     |  21 ++
 drivers/gpu/drm/Makefile                           |   1 +
 drivers/gpu/drm/panel/Kconfig                      |  13 +
 drivers/gpu/drm/panel/Makefile                     |   1 +
 drivers/gpu/drm/panel/panel-simple.c               | 339 +++++++++++++++++++++
 8 files changed, 396 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/panel/auo,b101aw03.txt
 create mode 100644 Documentation/devicetree/bindings/panel/chunghwa,claa101wb03.txt
 create mode 100644 Documentation/devicetree/bindings/panel/panasonic,vvx10f004b00.txt
 create mode 100644 Documentation/devicetree/bindings/panel/simple-panel.txt
 create mode 100644 drivers/gpu/drm/panel/Makefile
 create mode 100644 drivers/gpu/drm/panel/panel-simple.c

Comments

Stephen Warren Oct. 11, 2013, 10:33 p.m. UTC | #1
On 10/07/2013 02:34 AM, Thierry Reding wrote:
> 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 three panels: An AU Optronics 10.1" WSVGA, a
> Chunghwa Picture Tubes 10.1" WXGA and a Panasonic 10.1 WUXGA TFT LCD
> panel.

>  .../devicetree/bindings/panel/auo,b101aw03.txt     |   7 +
>  .../bindings/panel/chunghwa,claa101wb03.txt        |   7 +
>  .../bindings/panel/panasonic,vvx10f004b00.txt      |   7 +
>  .../devicetree/bindings/panel/simple-panel.txt     |  21 ++

Since this patch defines new DT bindings, it should also be sent to the
DT binding maintainers and DT mailing list.

> diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c

> +static int panel_simple_remove(struct platform_device *pdev)
> +{
> +	struct panel_simple *panel = platform_get_drvdata(pdev);
> +
> +	if (gpio_is_valid(panel->enable_gpio)) {
> +		if (panel->enable_gpio_flags & GPIO_ACTIVE_LOW)
> +			gpio_set_value(panel->enable_gpio, 1);
> +		else
> +			gpio_set_value(panel->enable_gpio, 0);
> +
> +		gpio_free(panel->enable_gpio);
> +	}
> +
> +	regulator_disable(panel->supply);

Can you just call panel_simple_disable() to do the HW cleanup, and just
do resource cleanup here?
Thierry Reding Oct. 14, 2013, 2:10 p.m. UTC | #2
On Fri, Oct 11, 2013 at 04:33:33PM -0600, Stephen Warren wrote:
> On 10/07/2013 02:34 AM, Thierry Reding wrote:
> > 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 three panels: An AU Optronics 10.1" WSVGA, a
> > Chunghwa Picture Tubes 10.1" WXGA and a Panasonic 10.1 WUXGA TFT LCD
> > panel.
> 
> >  .../devicetree/bindings/panel/auo,b101aw03.txt     |   7 +
> >  .../bindings/panel/chunghwa,claa101wb03.txt        |   7 +
> >  .../bindings/panel/panasonic,vvx10f004b00.txt      |   7 +
> >  .../devicetree/bindings/panel/simple-panel.txt     |  21 ++
> 
> Since this patch defines new DT bindings, it should also be sent to the
> DT binding maintainers and DT mailing list.

I Cc'ed at least the DT mailing list. The get_maintainer.pl generated
list was pretty large, and I keep getting different feedback about
whether it's a good idea to Cc individual people or just the relevant
mailing lists. In this case I assumed that all DT binding maintainers
would be reading the DT mailing list and therefore see the patches. I
can change my habit though if you prefer to get an extra copy.

One slight inconvenience with large series like this is that a lot of
work is required to handcraft an appropriate list of people and lists
to send the patches to. Furthermore I personally like receiving whole
patch series because it gives me full context, but other people seem
to want only the patches that they need to worry about. So what I
usually do is handcraft a list of people I want to send patches to
and use it for the whole series. If that list grows too large, I'll
usually trim it down to include only lists. Having to handcraft lists
for each individual patch doesn't sound that useful to me.

> > diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
> 
> > +static int panel_simple_remove(struct platform_device *pdev)
> > +{
> > +	struct panel_simple *panel = platform_get_drvdata(pdev);
> > +
> > +	if (gpio_is_valid(panel->enable_gpio)) {
> > +		if (panel->enable_gpio_flags & GPIO_ACTIVE_LOW)
> > +			gpio_set_value(panel->enable_gpio, 1);
> > +		else
> > +			gpio_set_value(panel->enable_gpio, 0);
> > +
> > +		gpio_free(panel->enable_gpio);
> > +	}
> > +
> > +	regulator_disable(panel->supply);
> 
> Can you just call panel_simple_disable() to do the HW cleanup, and just
> do resource cleanup here?

Yes, I can.

Thanks,
Thierry
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/panel/auo,b101aw03.txt b/Documentation/devicetree/bindings/panel/auo,b101aw03.txt
new file mode 100644
index 0000000..72e088a
--- /dev/null
+++ b/Documentation/devicetree/bindings/panel/auo,b101aw03.txt
@@ -0,0 +1,7 @@ 
+AU Optronics Corporation 10.1" WSVGA TFT LCD panel
+
+Required properties:
+- compatible: should be "auo,b101aw03"
+
+This binding is compatible with the simple-panel binding, which is specified
+in simple-panel.txt in this directory.
diff --git a/Documentation/devicetree/bindings/panel/chunghwa,claa101wb03.txt b/Documentation/devicetree/bindings/panel/chunghwa,claa101wb03.txt
new file mode 100644
index 0000000..0ab2c05
--- /dev/null
+++ b/Documentation/devicetree/bindings/panel/chunghwa,claa101wb03.txt
@@ -0,0 +1,7 @@ 
+Chunghwa Picture Tubes Ltd. 10.1" WXGA TFT LCD panel
+
+Required properties:
+- compatible: should be "chunghwa,claa101wb03"
+
+This binding is compatible with the simple-panel binding, which is specified
+in simple-panel.txt in this directory.
diff --git a/Documentation/devicetree/bindings/panel/panasonic,vvx10f004b00.txt b/Documentation/devicetree/bindings/panel/panasonic,vvx10f004b00.txt
new file mode 100644
index 0000000..d328b03
--- /dev/null
+++ b/Documentation/devicetree/bindings/panel/panasonic,vvx10f004b00.txt
@@ -0,0 +1,7 @@ 
+Panasonic Corporation 10.1" WUXGA TFT LCD panel
+
+Required properties:
+- compatible: should be "panasonic,vvx10f004b00"
+
+This binding is compatible with the simple-panel binding, which is specified
+in simple-panel.txt in this directory.
diff --git a/Documentation/devicetree/bindings/panel/simple-panel.txt b/Documentation/devicetree/bindings/panel/simple-panel.txt
new file mode 100644
index 0000000..1341bbf
--- /dev/null
+++ b/Documentation/devicetree/bindings/panel/simple-panel.txt
@@ -0,0 +1,21 @@ 
+Simple display panel
+
+Required properties:
+- power-supply: regulator to provide the supply voltage
+
+Optional properties:
+- ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
+- enable-gpios: GPIO pin to enable or disable the panel
+- backlight: phandle of the backlight device attached to the panel
+
+Example:
+
+	panel: panel {
+		compatible = "cptt,claa101wb01";
+		ddc-i2c-bus = <&panelddc>;
+
+		power-supply = <&vdd_pnl_reg>;
+		enable-gpios = <&gpio 90 0>;
+
+		backlight = <&backlight>;
+	};
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 81363a9..a9859e0 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -58,3 +58,4 @@  obj-$(CONFIG_DRM_QXL) += qxl/
 obj-$(CONFIG_DRM_MSM) += msm/
 obj-$(CONFIG_DRM_TEGRA) += tegra/
 obj-y			+= i2c/
+obj-y			+= panel/
diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 2ddd5bd..843087b 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -2,3 +2,16 @@  menuconfig DRM_PANEL
 	bool "DRM panel support"
 	help
 	  Panel registration and lookup framework.
+
+if DRM_PANEL
+
+config DRM_PANEL_SIMPLE
+	bool "support for simple panels"
+	depends on OF
+	help
+	  DRM panel driver for dumb panels that need at most a regulator and
+	  a GPIO to be powered up. Optionally a backlight can be attached so
+	  that it can be automatically turned off when the panel goes into a
+	  low power state.
+
+endif
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
new file mode 100644
index 0000000..af9dfa2
--- /dev/null
+++ b/drivers/gpu/drm/panel/Makefile
@@ -0,0 +1 @@ 
+obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
new file mode 100644
index 0000000..b0fb103
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -0,0 +1,339 @@ 
+/*
+ * 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/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;
+
+	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 void panel_simple_disable(struct drm_panel *panel)
+{
+	struct panel_simple *p = to_panel_simple(panel);
+
+	if (!p->enabled)
+		return;
+
+	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;
+}
+
+static void panel_simple_enable(struct drm_panel *panel)
+{
+	struct panel_simple *p = to_panel_simple(panel);
+	int err;
+
+	if (p->enabled)
+		return;
+
+	err = regulator_enable(p->supply);
+	if (err < 0)
+		dev_err(panel->dev, "failed to enable supply: %d\n", 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;
+}
+
+static int panel_simple_get_modes(struct drm_panel *panel)
+{
+	struct panel_simple *p = to_panel_simple(panel);
+	struct drm_display_mode *mode;
+	unsigned int i;
+
+	for (i = 0; i < p->desc->num_modes; i++) {
+		mode = drm_mode_duplicate(panel->drm, &p->desc->modes[i]);
+		if (!mode)
+			return -ENOMEM;
+
+		drm_mode_set_name(mode);
+
+		drm_mode_probed_add(panel->connector, mode);
+	}
+
+	return p->desc->num_modes;
+}
+
+static const struct drm_panel_funcs panel_simple_funcs = {
+	.disable = panel_simple_disable,
+	.enable = panel_simple_enable,
+	.get_modes = panel_simple_get_modes,
+};
+
+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 drm_display_mode panasonic_vvx10f004b00_mode = {
+	.clock = 154700,
+	.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 const struct of_device_id panel_simple_of_match[] = {
+	{
+		.compatible = "auo,b101aw03",
+		.data = &auo_b101aw03,
+	}, {
+		.compatible = "chunghwa,claa101wb01",
+		.data = &chunghwa_claa101wb01
+	}, {
+		.compatible = "panasonic,vvx10f004b00",
+		.data = &panasonic_vvx10f004b00
+	}, {
+		/* sentinel */
+	}
+};
+MODULE_DEVICE_TABLE(of, panel_simple_of_match);
+
+static int panel_simple_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *id;
+	struct device_node *backlight;
+	struct panel_simple *panel;
+	enum of_gpio_flags flags;
+	int err;
+
+	panel = devm_kzalloc(&pdev->dev, sizeof(*panel), GFP_KERNEL);
+	if (!panel)
+		return -ENOMEM;
+
+	id = of_match_node(panel_simple_of_match, pdev->dev.of_node);
+	if (!id)
+		return -ENODEV;
+
+	panel->desc = id->data;
+	panel->enabled = false;
+
+	panel->supply = devm_regulator_get(&pdev->dev, "power");
+	if (IS_ERR(panel->supply))
+		return PTR_ERR(panel->supply);
+
+	panel->enable_gpio = of_get_named_gpio_flags(pdev->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(&pdev->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(&pdev->dev, "failed to setup GPIO%u: %d\n",
+				panel->enable_gpio, err);
+			goto free_gpio;
+		}
+	}
+
+	backlight = of_parse_phandle(pdev->dev.of_node, "backlight", 0);
+	if (backlight) {
+		panel->backlight = of_find_backlight_by_node(backlight);
+		if (!panel->backlight) {
+			err = -EPROBE_DEFER;
+			goto free_gpio;
+		}
+
+		of_node_put(backlight);
+	}
+
+	drm_panel_init(&panel->base);
+	panel->base.dev = &pdev->dev;
+	panel->base.funcs = &panel_simple_funcs;
+
+	err = drm_panel_add(&panel->base);
+	if (err < 0)
+		goto free_gpio;
+
+	platform_set_drvdata(pdev, panel);
+
+	return 0;
+
+free_gpio:
+	if (gpio_is_valid(panel->enable_gpio))
+		gpio_free(panel->enable_gpio);
+
+	return err;
+}
+
+static int panel_simple_remove(struct platform_device *pdev)
+{
+	struct panel_simple *panel = platform_get_drvdata(pdev);
+
+	if (gpio_is_valid(panel->enable_gpio)) {
+		if (panel->enable_gpio_flags & GPIO_ACTIVE_LOW)
+			gpio_set_value(panel->enable_gpio, 1);
+		else
+			gpio_set_value(panel->enable_gpio, 0);
+
+		gpio_free(panel->enable_gpio);
+	}
+
+	regulator_disable(panel->supply);
+
+	if (panel->backlight)
+		put_device(&panel->backlight->dev);
+
+	drm_panel_detach(&panel->base);
+	drm_panel_remove(&panel->base);
+
+	return 0;
+}
+
+static struct platform_driver panel_simple_driver = {
+	.driver = {
+		.name = "panel-simple",
+		.owner = THIS_MODULE,
+		.of_match_table = panel_simple_of_match,
+	},
+	.probe = panel_simple_probe,
+	.remove = panel_simple_remove,
+};
+module_platform_driver(panel_simple_driver);
+
+MODULE_DESCRIPTION("DRM Driver for Simple Panels");
+MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
+MODULE_LICENSE("GPL v2");