[PATCH 0/5] ARM: dts: sun5i: q8-tablet: Complete LCD panel description

[PATCH 0/5] ARM: dts: sun5i: q8-tablet: Complete LCD panel description

[Chen-Yu Tsai]

Hi,

This series adds the missing bits for the LCD panel of the A13 Q8
tablets. The panel and backlight were missing their enable GPIOs.
The panel can have its power supply added as well, though it is not
a complete description. See the commit log of that patch for more
details. The backlight's power supply is the unregulator output of
the PMIC, which does not have a device tree representation.

For the Q8 tablets, the backlight GPIO is driven by a GPIO pin from
the PMIC. This needs a fix in the pwm backlight driver to avoid a
runtime warning. This will be sent separately.


Please have a look.

Regards
ChenYu

Chen-Yu Tsai (5):
  ARM: dts: sun5i: Add backlight GPIO for reference design tablet
  ARM: dts: sun5i: q8-tablet: Move panel properties to correct node
    level
  ARM: dts: sun5i: q8-tablet: Add LCD Panel enable GPIO
  ARM: dts: sun5i: q8-tablet: Add LCD Panel power supply
  ARM: dts: sun5i: q8-tablet: Use bananapi,s070wv20-ct16 panel
    compatible

 arch/arm/boot/dts/sun5i-a13-q8-tablet.dts            | 7 ++++---
 arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi | 2 +-
 2 files changed, 5 insertions(+), 4 deletions(-)

-- 
2.20.1

[PATCH 1/5] ARM: dts: sun5i: Add backlight GPIO for reference design tablet

[Chen-Yu Tsai]

Now that we support the GPIOs on the AXP209, we can control the LCD
backlight with them.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi b/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi
index 6202aabedbfe..5b1f0e198eb6 100644
--- a/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi
+++ b/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi
@@ -54,7 +54,7 @@
 		pwms = <&pwm 0 50000 PWM_POLARITY_INVERTED>;
 		brightness-levels = <0 10 20 30 40 50 60 70 80 90 100>;
 		default-brightness-level = <8>;
-		/* TODO: backlight uses axp gpio1 as enable pin */
+		enable-gpios = <&axp_gpio 1 GPIO_ACTIVE_HIGH>; /* AXP GPIO1 */
 	};
 
 	chosen {
-- 
2.20.1

[PATCH 2/5] ARM: dts: sun5i: q8-tablet: Move panel properties to correct node level

[Chen-Yu Tsai]

The panel backlight and enable GPIO comments were incorrectly placed
in the input port, while it should have been in the panel node itself.

Move them to the correct position.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm/boot/dts/sun5i-a13-q8-tablet.dts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
index a89f29fa3e40..3a844dae26f7 100644
--- a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
+++ b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
@@ -50,13 +50,13 @@
 
 	panel: panel {
 		compatible = "urt,umsh-8596md-t", "simple-panel";
+		/* TODO: lcd panel uses axp gpio0 as enable pin */
+		backlight = <&backlight>;
 		#address-cells = <1>;
 		#size-cells = <0>;
 
 		port@0 {
 			reg = <0>;
-			/* TODO: lcd panel uses axp gpio0 as enable pin */
-			backlight = <&backlight>;
 			#address-cells = <1>;
 			#size-cells = <0>;
 
-- 
2.20.1

[PATCH 3/5] ARM: dts: sun5i: q8-tablet: Add LCD Panel enable GPIO

[Chen-Yu Tsai]

Now that we support the AXP209 GPIOs, we can toggle the LCD panel enable
line. Add the GPIO phandle to the panel.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm/boot/dts/sun5i-a13-q8-tablet.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
index 3a844dae26f7..ead159f89e74 100644
--- a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
+++ b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
@@ -50,7 +50,7 @@
 
 	panel: panel {
 		compatible = "urt,umsh-8596md-t", "simple-panel";
-		/* TODO: lcd panel uses axp gpio0 as enable pin */
+		enable-gpios = <&axp_gpio 0 GPIO_ACTIVE_HIGH>; /* AXP GPIO0 */
 		backlight = <&backlight>;
 		#address-cells = <1>;
 		#size-cells = <0>;
-- 
2.20.1

[PATCH 4/5] ARM: dts: sun5i: q8-tablet: Add LCD Panel power supply

[Chen-Yu Tsai]

The A13 Q8 tablet, following the A13 reference tablet design, has the
system's fixed 3.3V rail feed the VCC supply of the LCD panel.
Additional voltage rails used by the panel are generated using a
regulator fed from the unregulated IPSOUT output of the PMIC. The latter
is unrepresentable in the device tree. Both are controlled with MOSFETs
by the enable GPIO added in the previous patch. The actual enable or
reset pin for the panel is tied directly to LCD-VCC after the MOSFET.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm/boot/dts/sun5i-a13-q8-tablet.dts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
index ead159f89e74..c77c0758145a 100644
--- a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
+++ b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
@@ -50,6 +50,7 @@
 
 	panel: panel {
 		compatible = "urt,umsh-8596md-t", "simple-panel";
+		power-supply = <&reg_vcc3v3>;
 		enable-gpios = <&axp_gpio 0 GPIO_ACTIVE_HIGH>; /* AXP GPIO0 */
 		backlight = <&backlight>;
 		#address-cells = <1>;
-- 
2.20.1

[PATCH 5/5] ARM: dts: sun5i: q8-tablet: Use bananapi,s070wv20-ct16 panel compatible

[Chen-Yu Tsai]

The compatible string for the LCD panel used for the Q8 tablets are just
a placeholder that was shown to be compatible with the actual panels
found on these devices. The real panels do not have any identifiable
markings and vary between production runs.

The compatibe string previously used had a pixel clock that could not
be accurately reproduced on Allwinner hardware, and discussions on
whether a margin should be added to the display drivers and how large
a margin was acceptable had stalled.

Now that we have a panel model that is actually used with Allwinner
hardware, has the same dimensions, and the timings have been shown to
work with the nameless panels, we can use that one instead.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm/boot/dts/sun5i-a13-q8-tablet.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
index c77c0758145a..7257f39b31ce 100644
--- a/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
+++ b/arch/arm/boot/dts/sun5i-a13-q8-tablet.dts
@@ -49,7 +49,7 @@
 	compatible = "allwinner,q8-a13", "allwinner,sun5i-a13";
 
 	panel: panel {
-		compatible = "urt,umsh-8596md-t", "simple-panel";
+		compatible = "bananapi,s070wv20-ct16", "simple-panel";
 		power-supply = <&reg_vcc3v3>;
 		enable-gpios = <&axp_gpio 0 GPIO_ACTIVE_HIGH>; /* AXP GPIO0 */
 		backlight = <&backlight>;
-- 
2.20.1

Re: [PATCH 1/5] ARM: dts: sun5i: Add backlight GPIO for reference design tablet

[Maxime Ripard]

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On Sun, Jan 27, 2019 at 10:48:34PM +0800, Chen-Yu Tsai wrote:
> Now that we support the GPIOs on the AXP209, we can control the LCD
> backlight with them.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Applied, thanks!
Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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Re: [PATCH 2/5] ARM: dts: sun5i: q8-tablet: Move panel properties to correct node level

[Maxime Ripard]

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On Sun, Jan 27, 2019 at 10:48:35PM +0800, Chen-Yu Tsai wrote:
> The panel backlight and enable GPIO comments were incorrectly placed
> in the input port, while it should have been in the panel node itself.
> 
> Move them to the correct position.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Applied, thanks!
Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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Re: [PATCH 3/5] ARM: dts: sun5i: q8-tablet: Add LCD Panel enable GPIO

[Maxime Ripard]

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On Sun, Jan 27, 2019 at 10:48:36PM +0800, Chen-Yu Tsai wrote:
> Now that we support the AXP209 GPIOs, we can toggle the LCD panel enable
> line. Add the GPIO phandle to the panel.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Applied, thanks!
Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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Re: [PATCH 4/5] ARM: dts: sun5i: q8-tablet: Add LCD Panel power supply

[Maxime Ripard]

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On Sun, Jan 27, 2019 at 10:48:37PM +0800, Chen-Yu Tsai wrote:
> The A13 Q8 tablet, following the A13 reference tablet design, has the
> system's fixed 3.3V rail feed the VCC supply of the LCD panel.
> Additional voltage rails used by the panel are generated using a
> regulator fed from the unregulated IPSOUT output of the PMIC. The latter
> is unrepresentable in the device tree. Both are controlled with MOSFETs
> by the enable GPIO added in the previous patch. The actual enable or
> reset pin for the panel is tied directly to LCD-VCC after the MOSFET.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Applied, thanks!
Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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Re: [PATCH 5/5] ARM: dts: sun5i: q8-tablet: Use bananapi,s070wv20-ct16 panel compatible

[Maxime Ripard]

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On Sun, Jan 27, 2019 at 10:48:38PM +0800, Chen-Yu Tsai wrote:
> The compatible string for the LCD panel used for the Q8 tablets are just
> a placeholder that was shown to be compatible with the actual panels
> found on these devices. The real panels do not have any identifiable
> markings and vary between production runs.
> 
> The compatibe string previously used had a pixel clock that could not
> be accurately reproduced on Allwinner hardware, and discussions on
> whether a margin should be added to the display drivers and how large
> a margin was acceptable had stalled.
> 
> Now that we have a panel model that is actually used with Allwinner
> hardware, has the same dimensions, and the timings have been shown to
> work with the nameless panels, we can use that one instead.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Applied, thanks!
Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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