[PATCH v2 2/2] ARM: sun7i: dts: Add LVDS panel support on A20

[andrey....@gmail.com]

From: Andrey Lebedev <and...@lebedev.lt>

Define pins for LVDS channels 0 and 1, configure reset line for tcon0 and
provide sample LVDS panel, connected to tcon0.

Signed-off-by: Andrey Lebedev <and...@lebedev.lt>
---
arch/arm/boot/dts/sun7i-a20.dtsi | 45 +++++++++++++++++++++++++++++---
1 file changed, 42 insertions(+), 3 deletions(-)

diff --git a/arch/arm/boot/dts/sun7i-a20.dtsi b/arch/arm/boot/dts/sun7i-a20.dtsi
index 92b5be97085d..b05fdf8df32e 100644
--- a/arch/arm/boot/dts/sun7i-a20.dtsi
+++ b/arch/arm/boot/dts/sun7i-a20.dtsi
@@ -47,6 +47,7 @@
#include <dt-bindings/dma/sun4i-a10.h>
#include <dt-bindings/clock/sun7i-a20-ccu.h>
#include <dt-bindings/reset/sun4i-a10-ccu.h>
+#include <dt-bindings/pinctrl/sun4i-a10.h>

/ {
interrupt-parent = <&gic>;
@@ -407,8 +408,8 @@
compatible = "allwinner,sun7i-a20-tcon";
reg = <0x01c0c000 0x1000>;
interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
- resets = <&ccu RST_TCON0>;
- reset-names = "lcd";
+ resets = <&ccu RST_TCON0>, <&ccu RST_LVDS>;
+ reset-names = "lcd", "lvds";
clocks = <&ccu CLK_AHB_LCD0>,
<&ccu CLK_TCON0_CH0>,
<&ccu CLK_TCON0_CH1>;
@@ -444,6 +445,11 @@
#size-cells = <0>;
reg = <1>;

+ tcon0_out_lvds: endpoint@0 {
+ reg = <0>;
+ remote-endpoint = <&lvds_in_tcon0>;
+ allwinner,tcon-channel = <0>;
+ };
tcon0_out_hdmi: endpoint@1 {
reg = <1>;
remote-endpoint = <&hdmi_in_tcon0>;
@@ -686,6 +692,19 @@
};
};

+ lvds_panel: panel@1c16500 {
+ compatible = "panel-lvds";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+
+ port {
+ lvds_in_tcon0: endpoint {
+ remote-endpoint = <&tcon0_out_lvds>;
+ };
+ };
+ };
+
spi2: spi@1c17000 {
compatible = "allwinner,sun4i-a10-spi";
reg = <0x01c17000 0x1000>;
@@ -872,7 +891,7 @@
gmac_rgmii_pins: gmac-rgmii-pins {
pins = "PA0", "PA1", "PA2",
"PA3", "PA4", "PA5", "PA6",
- "PA7", "PA8", "PA10",
+ "PA7", "PA8", "PA10",
"PA11", "PA12", "PA13",
"PA15", "PA16";
function = "gmac";
@@ -1162,6 +1181,26 @@
pins = "PI20", "PI21";
function = "uart7";
};
+
+ /omit-if-no-ref/
+ lcd_lvds0_pins: lcd_lvds0_pins {
+ allwinner,pins =
+ "PD0", "PD1", "PD2", "PD3", "PD4",
+ "PD5", "PD6", "PD7", "PD8", "PD9";
+ allwinner,function = "lvds0";
+ allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+ allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
+ };
+
+ /omit-if-no-ref/
+ lcd_lvds1_pins: lcd_lvds1_pins {
+ allwinner,pins =
+ "PD10", "PD11", "PD12", "PD13", "PD14",
+ "PD15", "PD16", "PD17", "PD18", "PD19";
+ allwinner,function = "lvds1";
+ allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+ allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
+ };
};

timer@1c20c00 {
--
2.20.1

[Andrey Lebedev]

On Thu, Feb 13, 2020 at 10:43:04AM +0100, Maxime Ripard wrote:

> On Thu, Feb 13, 2020 at 12:23:57AM +0200, andrey....@gmail.com wrote:
> > From: Andrey Lebedev <and...@lebedev.lt>
> >
> > Define pins for LVDS channels 0 and 1, configure reset line for tcon0 and
> > provide sample LVDS panel, connected to tcon0.
> >
> > Signed-off-by: Andrey Lebedev <and...@lebedev.lt>
>

> And this prefix should be ARM: dts: sun7i ;)

Ah, thanks, I think I've got the pattern now!

> > + /omit-if-no-ref/
> > + lcd_lvds0_pins: lcd_lvds0_pins {
>

> underscores in the node names will create a dtc warning at
> compilation, you should use lcd-lvds0-pins instead.

You're right, I wasn't following the naming convention here. dtc doesn't
produce any warning on this though. Fixed that anyway.

> This will create a spurious warning message for TCON1, since we
> adjusted the driver to tell it supports LVDS, but there's no LVDS
> reset line, so we need to make it finer grained.

Yes, I can attribute two of the messages in my dmesg log [1] to this
("Missing LVDS properties" and "LVDS output disabled". "sun4i-tcon
1c0d000.lcd-controller" is indeed tcon1). And yes, I can see how they
can be confusing to someone.

I'd need some pointers on how to deal with that though (if we want to do
it in this scope).

[1] excerpt from kernel boot log:

[ 4.890975] sun4i-drm display-engine: bound 1e00000.display-frontend (ops sun4i_frontend_driver_exit [sun4i_frontend])
[ 4.902032] sun4i-drm display-engine: bound 1e20000.display-frontend (ops sun4i_frontend_driver_exit [sun4i_frontend])
[ 4.913467] sun4i-drm display-engine: bound 1e60000.display-backend (ops sun4i_backend_ops [sun4i_backend])
[ 4.923806] sun4i-drm display-engine: bound 1e40000.display-backend (ops sun4i_backend_ops [sun4i_backend])
[ 4.934451] sun4i-drm display-engine: bound 1c0c000.lcd-controller (ops sun4i_tcon_platform_driver_exit [sun4i_tcon])
[ 4.945254] sun4i-tcon 1c0d000.lcd-controller: Missing LVDS properties, Please upgrade your DT
[ 4.953935] sun4i-tcon 1c0d000.lcd-controller: LVDS output disabled
[ 4.960857] sun4i-drm display-engine: No panel or bridge found... RGB output disabled
[ 4.968845] sun4i-drm display-engine: bound 1c0d000.lcd-controller (ops sun4i_tcon_platform_driver_exit [sun4i_tcon])
[ 5.080874] sun4i-drm display-engine: bound 1c16000.hdmi (ops sun4i_hdmi_driver_exit [sun4i_drm_hdmi])
[ 5.110087] [drm] Initialized sun4i-drm 1.0.0 20150629 for display-engine on minor 0
[ 5.763064] sun4i-drm display-engine: fb0: sun4i-drmdrmfb frame buffer device


--
Andrey Lebedev aka -.- . -.. -.. . .-.
Software engineer
Homepage: http://lebedev.lt/

[Andrey Lebedev]

On Fri, Feb 14, 2020 at 08:52:18AM +0100, Maxime Ripard wrote:
> > > This will create a spurious warning message for TCON1, since we
> > > adjusted the driver to tell it supports LVDS, but there's no LVDS
> > > reset line, so we need to make it finer grained.
> >
> > Yes, I can attribute two of the messages in my dmesg log [1] to this
> > ("Missing LVDS properties" and "LVDS output disabled". "sun4i-tcon
> > 1c0d000.lcd-controller" is indeed tcon1). And yes, I can see how they
> > can be confusing to someone.
> >
> > I'd need some pointers on how to deal with that though (if we want to do
> > it in this scope).
>

> Like I was mentionning, you could introduce a new compatible for each
> TCON (tcon0 and tcon1) and only set the support_lvds flag for tcon0

Can you give me an idea how that compatible might look like?

tcon0: lcd-controller@1c0c000 {
compatible = "allwinner,sun7i-a20-tcon", "allwinner,lvds";

or

tcon0: lcd-controller@1c0c000 {
compatible = "allwinner,sun7i-a20-tcon", "allwinner,tcon0";

? Or something completely different?

[Andrey Lebedev]

On Fri, Feb 14, 2020 at 09:53:51AM +0100, Maxime Ripard wrote:

> Something like
>
> &tcon0 {
> compatible = "allwinner,sun7i-a20-tcon0", "allwinner,sun7i-a20-tcon";
> };
>
> &tcon1 {
> compatible = "allwinner,sun7i-a20-tcon1", "allwinner,sun7i-a20-tcon";
> };
>

Hi Maxime, here is what I came up with, please take a look. If the
approach is right, I'll split it up and include into the patch set.

From f3e45c958a9551a52ac26435785bdb572e54d8db Mon Sep 17 00:00:00 2001
From: Andrey Lebedev <and...@lebedev.lt>
Date: Fri, 14 Feb 2020 23:21:59 +0200
Subject: [PATCH] Mark tcon0 to be the only tcon capable of LVDS on sun7i-a20

This allows to avoid warnings about reset line not provided for tcon1.

Signed-off-by: Andrey Lebedev <and...@lebedev.lt>
---

arch/arm/boot/dts/sun7i-a20.dtsi | 2 +-
drivers/gpu/drm/sun4i/sun4i_tcon.c | 22 +++++++++++++++++++++-
drivers/gpu/drm/sun4i/sun4i_tcon.h | 2 ++
3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/sun7i-a20.dtsi b/arch/arm/boot/dts/sun7i-a20.dtsi
index 3b3c366a2bee..bab59fc4d9b1 100644
--- a/arch/arm/boot/dts/sun7i-a20.dtsi
+++ b/arch/arm/boot/dts/sun7i-a20.dtsi
@@ -405,7 +405,7 @@
};

tcon0: lcd-controller@1c0c000 {
- compatible = "allwinner,sun7i-a20-tcon";
+ compatible = "allwinner,sun7i-a20-tcon0", "allwinner,sun7i-a20-tcon";

reg = <0x01c0c000 0x1000>;
interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;

resets = <&ccu RST_TCON0>, <&ccu RST_LVDS>;

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 800a9bd86112..cb2040aec436 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -1107,6 +1107,25 @@ static struct sunxi_engine *sun4i_tcon_find_engine(struct sun4i_drv *drv,
return sun4i_tcon_find_engine_traverse(drv, node, 0);
}

+/*
+ * Check if given tcon supports LVDS
+ *
+ * Some of the sunxi SoC variants contain several timing controllers, but only
+ * one of them can be used to drive LVDS screen. In this case such tcon is
+ * identified in respective quirks struct: lvds_compatible_tcon property will
+ * hold "compatible" string of the tcon, that supports LVDS.
+ *
+ * If lvds_compatible_tcon is not set, all tcons are considered capable of
+ * driving LVDS.
+ */
+static bool sun4i_tcon_lvds_compat(struct device *dev, struct sun4i_tcon *tcon)
+{
+ if (tcon->quirks->lvds_compatible_tcon == NULL)
+ return true;
+ return of_device_is_compatible(dev->of_node,
+ tcon->quirks->lvds_compatible_tcon);
+}
+
static int sun4i_tcon_bind(struct device *dev, struct device *master,
void *data)
{
@@ -1161,7 +1180,7 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master,
return ret;
}

- if (tcon->quirks->supports_lvds) {
+ if (tcon->quirks->supports_lvds && sun4i_tcon_lvds_compat(dev, tcon)) {
/*
* This can only be made optional since we've had DT
* nodes without the LVDS reset properties.
@@ -1481,6 +1500,7 @@ static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {

static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
.supports_lvds = true,
+ .lvds_compatible_tcon = "allwinner,sun7i-a20-tcon0",
.has_channel_0 = true,
.has_channel_1 = true,
.dclk_min_div = 4,
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index cfbf4e6c1679..bc87d28ee341 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -235,6 +235,8 @@ struct sun4i_tcon_quirks {
bool needs_de_be_mux; /* sun6i needs mux to select backend */
bool needs_edp_reset; /* a80 edp reset needed for tcon0 access */
bool supports_lvds; /* Does the TCON support an LVDS output? */
+ /* "compatible" string of TCON that exclusively supports LVDS */
+ const char *lvds_compatible_tcon;
u8 dclk_min_div; /* minimum divider for TCON0 DCLK */

/* callback to handle tcon muxing options */
--
2.20.1

[@lex]

Hi Andrey,

I have a couple of 15" LCDs (different makers) with Cubieboard A20 (kernel 3.4) i would like to test your implementation if possible.

Can you share a kernel tree with your code and where should i change the timings for each Panel?

BR

@lex

[Andrey Lebedev]

On Saturday, February 15, 2020 at 4:20:33 PM UTC+2, @lex wrote:

Hi Andrey,

I have a couple of 15" LCDs (different makers) with Cubieboard A20 (kernel 3.4) i would like to test your implementation if possible.

Can you share a kernel tree with your code and where should i change the timings for each Panel?

Hi @lex,

I've shared my device tree here: https://gitlab.freedesktop.org/lima/mesa/issues/131#note_405869. I believe you have to adapt timings either from panel datasheet or (if you have .fex file with the timings) according to formulas here: https://linux-sunxi.org/LCD. 

The patches for LVDS support are under review right now, I keep the most up-to-date version here: https://github.com/kedder/linux/tree/a20-lvds-support

If you have big screen like that, you might need to include another pin set for LVDS channel 1. They are already included in my changes on a20-lvds-support branch, see https://github.com/kedder/linux/commit/44eb271c79869394247b560667eb59dce2ddc1c9.

[@lex]

Hi Andrey,

Thank you for sharing your work.

I can remember 2 channel was needed for the 1920x1080 res. in fact the panel is 17"

I need to find the fex files, must be somewhere here... :)

I will try with your kernel and see what i get. Busy weekend ahead...

I will post the results.

BR

@lex

[@lex]

Hi Andrey,

I have found my fex file for an 18.4" Panel. I have a hard time to figure out how to enable the dual channel in the dts, can you have a look at it and help how to enable it?

Here are the timings:

[lcd0_para]
lcd_used = 1
lcd_x = 1920
lcd_y = 1080
lcd_dclk_freq = 69
lcd_pwm_not_used = 0
lcd_pwm_ch = 0
lcd_pwm_freq = 10000
lcd_pwm_pol = 0
lcd_if = 3
lcd_hbp = 160
lcd_ht = 2084
lcd_vbp = 31
lcd_vt = 2226
lcd_hv_if = 0
lcd_hv_smode = 0
lcd_hv_s888_if = 0
lcd_hv_syuv_if = 0
lcd_hv_vspw = 0
lcd_hv_hspw = 0
lcd_lvds_ch = 1
lcd_lvds_mode = 0
lcd_lvds_bitwidth = 1
lcd_lvds_io_cross = 0
lcd_cpu_if = 0
lcd_frm = 1
lcd_io_cfg0 = 268435456
lcd_gamma_correction_en = 0
lcd_gamma_tbl_0 = 0x0
lcd_gamma_tbl_1 = 0x10101
lcd_gamma_tbl_255 = 0xffffff
lcd_bl_en_used = 1
lcd_bl_en = port:PH07<1><0><default><1>
lcd_power_used = 1
lcd_power = port:PH08<1><0><default><1>
lcd_pwm_used = 1
lcd_pwm = port:PB02<2><0><default><default>
lcd_gpio_0 =
lcd_gpio_1 =
lcd_gpio_2 =
lcd_gpio_3 =
lcdd0 = port:PD00<2><0><default><default>
lcdd1 = port:PD01<2><0><default><default>
lcdd2 = port:PD02<2><0><default><default>
lcdd3 = port:PD03<2><0><default><default>
lcdd4 = port:PD04<2><0><default><default>
lcdd5 = port:PD05<2><0><default><default>
lcdd6 = port:PD06<2><0><default><default>
lcdd7 = port:PD07<2><0><default><default>
lcdd8 = port:PD08<2><0><default><default>
lcdd9 = port:PD09<2><0><default><default>
lcdd10 = port:PD10<2><0><default><default>
lcdd11 = port:PD11<2><0><default><default>
lcdd12 = port:PD12<2><0><default><default>
lcdd13 = port:PD13<2><0><default><default>
lcdd14 = port:PD14<2><0><default><default>
lcdd15 = port:PD15<2><0><default><default>
lcdd16 = port:PD16<2><0><default><default>
lcdd17 = port:PD17<2><0><default><default>
lcdd18 = port:PD18<2><0><default><default>
lcdd19 = port:PD19<2><0><default><default>
lcdd20 = port:PD20<2><0><default><default>
lcdd21 = port:PD21<2><0><default><default>
lcdd22 = port:PD22<2><0><default><default>
lcdd23 = port:PD23<2><0><default><default>
lcdclk = port:PD24<2><0><default><default>
lcdde = port:PD25<2><0><default><default>
lcdhsync = port:PD26<2><0><default><default>
lcdvsync = port:PD27<2><0><default><default>

how would be the dts equivalent? And how about PD28,PD23,PD24,PD25,PD26 and PD27 pins?

    panel {
        compatible = "panel-lvds";
        width-mm = <>;
        height-mm = <>;
        pinctrl-names = "default";
        pinctrl-0 = <&lcd_enable_pin &lcd_lvds0_pins>;

        pinctrl-1 = <&lcd_enable_pin &lcd_lvds1_pins>;

        enable-gpios = <&pio 7 7 GPIO_ACTIVE_HIGH>; /* PH7 */
        data-mapping = "jeida-18";
        #address-cells = <1>;
        #size-cells = <0>;
        panel-timing {
            clock-frequency = <69000000>;
            hactive = <1920>;
            vactive = <1080>;
            hsync-len = <1>;
            hfront-porch = <>;
            hback-porch = <>;
            vsync-len = <1>;
            vfront-porch = <>;
            vback-porch = <>;
        };
        port {
            lvds_panel_in: endpoint {
                remote-endpoint = <&display_out_rgb>;
            };
        };
    };

BR

@lex

[Andrey Lebedev]

@lex, to get timings for panel you need to follow instructions on
https://linux-sunxi.org/LCD (see "FEX conversion rules"). I understand
that's pretty boring, but that's the only reliable way I know.

I would recommend to start by making your panel to work under u-boot.
U-boot has to be compiled with certain CONFIG_VIDEO_LCD_MODE
configuration value. Then screen should initialize before even kernel is
loaded and started. You will know it is working if you see the boot log
from u-boot on screen. You don't need any devicetree for that, just the
right config for compiling. You can get example from our openvario
project:
https://github.com/Openvario/meta-openvario/blob/warrior/recipes-bsp/u-boot/files/openvario-57-lvds/openvario_defconfig.
See CONFIG_VIDEO_* options.

If you get it working under u-boot, you might get a simple framebuffer
in kernel for free (my patches are not strictly needed for that). If you
need graphics acceleration from lima driver, you might also want to
apply my patches and get the devicetree file right. But first, try to
make it work under u-boot.

On 2/18/20 12:04 AM, @lex wrote:
> Hi Andrey,
>

> lcd_bl_en =port:PH07<1><0><default><1>
> lcd_power_used =1
> lcd_power =port:PH08<1><0><default><1>
> lcd_pwm_used =1
> lcd_pwm =port:PB02<2><0><default><default>

> lcd_gpio_0 =
> lcd_gpio_1 =
> lcd_gpio_2 =
> lcd_gpio_3 =

> lcdd0 =port:PD00<2><0><default><default>
> lcdd1 =port:PD01<2><0><default><default>
> lcdd2 =port:PD02<2><0><default><default>
> lcdd3 =port:PD03<2><0><default><default>
> lcdd4 =port:PD04<2><0><default><default>
> lcdd5 =port:PD05<2><0><default><default>
> lcdd6 =port:PD06<2><0><default><default>
> lcdd7 =port:PD07<2><0><default><default>
> lcdd8 =port:PD08<2><0><default><default>
> lcdd9 =port:PD09<2><0><default><default>
> lcdd10 =port:PD10<2><0><default><default>
> lcdd11 =port:PD11<2><0><default><default>
> lcdd12 =port:PD12<2><0><default><default>
> lcdd13 =port:PD13<2><0><default><default>
> lcdd14 =port:PD14<2><0><default><default>
> lcdd15 =port:PD15<2><0><default><default>
> lcdd16 =port:PD16<2><0><default><default>
> lcdd17 =port:PD17<2><0><default><default>
> lcdd18 =port:PD18<2><0><default><default>
> lcdd19 =port:PD19<2><0><default><default>
> lcdd20 =port:PD20<2><0><default><default>
> lcdd21 =port:PD21<2><0><default><default>
> lcdd22 =port:PD22<2><0><default><default>
> lcdd23 =port:PD23<2><0><default><default>
> lcdclk =port:PD24<2><0><default><default>
> lcdde =port:PD25<2><0><default><default>
> lcdhsync =port:PD26<2><0><default><default>
> lcdvsync =port:PD27<2><0><default><default>

> <https://www.google.com/url?q=https%3A%2F%2Fgitlab.freedesktop.org%2Flima%2Fmesa%2Fissues%2F131%23note_405869&sa=D&sntz=1&usg=AFQjCNGLsHoqWxFOjgRhKWl6gbc1IQzxGQ>.

> I believe you have to adapt timings either from panel datasheet
> or (if you have .fex file with the timings) according to
> formulas here: https://linux-sunxi.org/LCD

> <https://linux-sunxi.org/LCD>.

>
> The patches for LVDS support are under review right now, I keep
> the most up-to-date version here:
> https://github.com/kedder/linux/tree/a20-lvds-support
> <https://github.com/kedder/linux/tree/a20-lvds-support>
>
> If you have big screen like that, you might need to include
> another pin set for LVDS channel 1. They are already included in
> my changes on a20-lvds-support branch, see
> https://github.com/kedder/linux/commit/44eb271c79869394247b560667eb59dce2ddc1c9

> <https://github.com/kedder/linux/commit/44eb271c79869394247b560667eb59dce2ddc1c9>.
>
>
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[Andrey Lebedev]

On Mon, Feb 17, 2020 at 06:51:35PM +0100, Maxime Ripard wrote:
> > diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> > index cfbf4e6c1679..bc87d28ee341 100644
> > --- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
> > +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> > @@ -235,6 +235,8 @@ struct sun4i_tcon_quirks {
> > bool needs_de_be_mux; /* sun6i needs mux to select backend */
> > bool needs_edp_reset; /* a80 edp reset needed for tcon0 access */
> > bool supports_lvds; /* Does the TCON support an LVDS output? */
> > + /* "compatible" string of TCON that exclusively supports LVDS */
> > + const char *lvds_compatible_tcon;
>

> However this is far more complicated than needed, you can simply add a
> new quirks structure associated to the tcon0 compatible in
> sun4i_tcon_of_table, and that will do

Aha! Does this look good to you?

From 4ad2978e404c63d4cca1b7890bc5bdd4d1e8965d Mon Sep 17 00:00:00 2001
From: Andrey Lebedev <and...@lebedev.lt>
Date: Tue, 18 Feb 2020 19:47:33 +0200

Subject: [PATCH] Mark tcon0 to be the only tcon capable of LVDS on sun7i-a20

This allows to avoid warnings about reset line not provided for tcon1.

Signed-off-by: Andrey Lebedev <and...@lebedev.lt>
---

arch/arm/boot/dts/sun7i-a20.dtsi | 6 ++++--
drivers/gpu/drm/sun4i/sun4i_tcon.c | 14 ++++++++++++--
2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/arch/arm/boot/dts/sun7i-a20.dtsi b/arch/arm/boot/dts/sun7i-a20.dtsi
index dc4f3f249aee..d50263c1ca9a 100644
--- a/arch/arm/boot/dts/sun7i-a20.dtsi
+++ b/arch/arm/boot/dts/sun7i-a20.dtsi
@@ -405,7 +405,8 @@

};

tcon0: lcd-controller@1c0c000 {
- compatible = "allwinner,sun7i-a20-tcon";
+ compatible = "allwinner,sun7i-a20-tcon0",

+ "allwinner,sun7i-a20-tcon";

reg = <0x01c0c000 0x1000>;
interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
resets = <&ccu RST_TCON0>, <&ccu RST_LVDS>;

@@ -460,7 +461,8 @@
};

tcon1: lcd-controller@1c0d000 {
- compatible = "allwinner,sun7i-a20-tcon";
+ compatible = "allwinner,sun7i-a20-tcon1",
+ "allwinner,sun7i-a20-tcon";
reg = <0x01c0d000 0x1000>;
interrupts = <GIC_SPI 45 IRQ_TYPE_LEVEL_HIGH>;
resets = <&ccu RST_TCON1>;
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 800a9bd86112..d9605d331010 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -1479,7 +1479,7 @@ static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {
.dclk_min_div = 1,
};

-static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
+static const struct sun4i_tcon_quirks sun7i_a20_tcon0_quirks = {
.supports_lvds = true,

.has_channel_0 = true,
.has_channel_1 = true,

@@ -1489,6 +1489,15 @@ static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
.setup_lvds_phy = sun4i_tcon_setup_lvds_phy,
};

+static const struct sun4i_tcon_quirks sun7i_a20_tcon1_quirks = {
+ .supports_lvds = false,
+ .has_channel_0 = true,
+ .has_channel_1 = true,
+ .dclk_min_div = 4,
+ /* Same display pipeline structure as A10 */
+ .set_mux = sun4i_a10_tcon_set_mux,
+};
+
static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
.has_channel_0 = true,
.has_lvds_alt = true,
@@ -1534,7 +1543,8 @@ const struct of_device_id sun4i_tcon_of_table[] = {
{ .compatible = "allwinner,sun5i-a13-tcon", .data = &sun5i_a13_quirks },
{ .compatible = "allwinner,sun6i-a31-tcon", .data = &sun6i_a31_quirks },
{ .compatible = "allwinner,sun6i-a31s-tcon", .data = &sun6i_a31s_quirks },
- { .compatible = "allwinner,sun7i-a20-tcon", .data = &sun7i_a20_quirks },
+ { .compatible = "allwinner,sun7i-a20-tcon0", .data = &sun7i_a20_tcon0_quirks },
+ { .compatible = "allwinner,sun7i-a20-tcon1", .data = &sun7i_a20_tcon1_quirks },
{ .compatible = "allwinner,sun8i-a23-tcon", .data = &sun8i_a33_quirks },
{ .compatible = "allwinner,sun8i-a33-tcon", .data = &sun8i_a33_quirks },
{ .compatible = "allwinner,sun8i-a83t-tcon-lcd", .data = &sun8i_a83t_lcd_quirks },