[PATCH 1/2] arm64: dts: ti: Add overlay for OLDI-LCD1EVM Display and touch screen
Andrew Davis
afd at ti.com
Tue Apr 25 10:44:54 PDT 2023
On 4/25/23 12:00 PM, Aradhya Bhatia wrote:
> Hi Andrew,
>
> On 25-Apr-23 20:39, Andrew Davis wrote:
>> On 4/25/23 12:12 AM, Aradhya Bhatia wrote:
>>> From: Jyri Sarha <jsarha at ti.com>
>>>
>>> The OLDI-LCD1EVM add on board has Rocktech RK101II01D-CT panel with
>>> integrated touch screen. The integrated touch screen is Goodix GT928.
>>> Add DT nodes for these and connect the endpoint nodes with DSS.
>>>
>>> This patch was picked from TI's public tree based on 5.10 LTS kernel.
>>>
>>> Signed-off-by: Jyri Sarha <jsarha at ti.com>
>>> Signed-off-by: Nikhil Devshatwar <nikhil.nd at ti.com>
>>> [abhatia1 at ti.com: Make syntax changes to support 6.1 DTSO format]
>>> Signed-off-by: Aradhya Bhatia <a-bhatia1 at ti.com>
>>> ---
>>> arch/arm64/boot/dts/ti/Makefile | 2 +
>>> .../dts/ti/k3-am654-evm-oldi-lcd1evm.dtso | 70 +++++++++++++++++++
>>> 2 files changed, 72 insertions(+)
>>> create mode 100644
>>> arch/arm64/boot/dts/ti/k3-am654-evm-oldi-lcd1evm.dtso
>>>
>>> diff --git a/arch/arm64/boot/dts/ti/Makefile
>>> b/arch/arm64/boot/dts/ti/Makefile
>>> index 6acd12409d59..8956b19e587a 100644
>>> --- a/arch/arm64/boot/dts/ti/Makefile
>>> +++ b/arch/arm64/boot/dts/ti/Makefile
>>> @@ -26,6 +26,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-am6548-iot2050-advanced.dtb
>>> dtb-$(CONFIG_ARCH_K3) += k3-am6548-iot2050-advanced-m2.dtb
>>> dtb-$(CONFIG_ARCH_K3) += k3-am6548-iot2050-advanced-pg2.dtb
>>> dtb-$(CONFIG_ARCH_K3) += k3-am654-base-board.dtb
>>> +dtb-$(CONFIG_ARCH_K3) += k3-am654-evm-oldi-lcd1evm.dtbo
>>
>> This name is a bit odd, why "evm" twice? Looks like the first instance
>> is the redundant one as most of the documents on this LCD board call it
>> the "LCD1EVM". How about:
>>
>> k3-am654-lcd1evm.dtbo
>
> I didn't think I could change the name of the overlay picking the patch
> from our tree, but if we are going to do it, can we take up another
> approach, where it would be easier to add panels for AM62x family and
> ensure uniformity throughout.
>
Yes, we can change what we want when upstreaming. How we did it in our
evil vendor tree should in no way prevent us from doing things better
in upstream.
> We have 2 different panels from Vendor A, and another one from Vendor B.
> Vendor B panel connects to AM625-SK via an adapter board.
>
> Vendor-A/Panel-1 only says the name, 'SK-LCD1' on its circuit board.
> Vendor-A/Panel-2 doesn't have any name yet. We only have development
> units.
> Vendor-B/Panel-2 mentions '$(LCD_model) to AM62x SoC adapter board'.
>
> Since, there are too many manufacturers, it is difficult to maintain
> uniformity with the names of panel-boards. So, I have this approach in
> mind (which I have used for our tree for AM62x), but would like your
> comments.
>
> k3-$soc-$board-$(panel_vendor)-$(brief_compatible).dtso
>
> So, for AM625-SKs,
> k3-am625-sk-$(vendor_name)-$(brief_compatible).dtso
>
Looks reasonable to me.
> and for the current panel Rocktech RK101II01D-CT, which applies on AM654
> base-board,
>
> k3-am654-base-board-rocktech-rk101.dtso.
>
> This does become rather long, but also is distinguishable.
>
No limit to file names here, being clear and distinguishable is more
important than short names.
> Let me know what you think.
>
>>
>> I would like the overlay names to give some hint to what base DTB they
>> apply to,
>
> Agreed. That is indeed how it should be.
>
>> or better yet, apply them here in the build which will check
>> that they apply cleanly. Plus you can drop the silly "+= -@" below.
>>
>
> The above approach will give a hint of the base EVM where a combined
> build is not possible simply because there is no 'official' name for a
> particular combination of panel and EVM.
>
We do not need to name each possible combination (and we shouldn't, there
would be a combinatorial explosion, avoiding that is the whole point
of using overlays vs .dtsi includes).
I do think we should name at least the combinations that we ship together.
So as below for AM654 that would be the GPEVM and the IDK. Those are the
two out-of-box combinations available for purchase as a kit. Folks can still
buy additional add-on cards, and/or mix and match from those two sets.
As long as we have at least one named combination, then the base-board dtb
file gets symbols automatically and we can drop the "+= -@" line.
Andrew
>
> Regards
> Aradhya
>
>> Let's see how this should be called, from the AM65x GP EVM doc[0] we
>> get a nice picture on page 5 and the following:
>>
>> "The AM65x GP EVM consists of a common processor board, an LCD adapter,
>> and a one-lane PCIe/USB3 personality card."
>>
>> So, this would translate to:
>>
>> k3-am654-gp-evm-dtbs := k3-am654-base-board.dtb k3-am654-lcd1evm.dtbo
>> k3-am654-pcie-usb3.dtbo
>> dtb-$(CONFIG_ARCH_K3) += k3-am654-gp-evm.dtb>
>> Next, from the AM65x IDK doc[1] also with a nice image on page 5:
>>
>> "The AM65x IDK consists of a common processor board, IDK application board,
>> and a two-lane PCIe personality card.:
>>
>> So:
>>
>> k3-am654-idk-dtbs := k3-am654-base-board.dtb k3-am654-idk.dtbo
>> k3-am654-pcie-usb2.dtbo
>> dtb-$(CONFIG_ARCH_K3) += k3-am654-idk.dtb
>>
>> Note that we do have all those missing dtso files in our evil vendor
>> tree[2]
>> and will be upstreaming them next, so this naming should all work out
>> nicely.
>>
>> Andrew
>>
>> [0] https://www.ti.com/lit/ug/spruim7/spruim7.pdf
>> [1] https://www.ti.com/lit/ug/spruim6a/spruim6a.pdf
>> [2]
>> https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/tree/arch/arm64/boot/dts/ti?h=ti-linux-5.10.y
>>
>>> # Boards with J7200 SoC
>>> dtb-$(CONFIG_ARCH_K3) += k3-j7200-common-proc-board.dtb
>>> @@ -45,3 +46,4 @@ dtb-$(CONFIG_ARCH_K3) += k3-j784s4-evm.dtb
>>> # Enable support for device-tree overlays
>>> DTC_FLAGS_k3-am6548-iot2050-advanced-m2 += -@
>>> +DTC_FLAGS_k3-am654-base-board += -@
>>> diff --git a/arch/arm64/boot/dts/ti/k3-am654-evm-oldi-lcd1evm.dtso
>>> b/arch/arm64/boot/dts/ti/k3-am654-evm-oldi-lcd1evm.dtso
>>> new file mode 100644
>>> index 000000000000..b2c790b314cf
>>> --- /dev/null
>>> +++ b/arch/arm64/boot/dts/ti/k3-am654-evm-oldi-lcd1evm.dtso
>>> @@ -0,0 +1,70 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/**
>>> + * OLDI-LCD1EVM Rocktech integrated panel and touch DT overlay for
>>> AM654-EVM.
>>> + *
>>> + * Copyright (C) 2023 Texas Instruments Incorporated -
>>> http://www.ti.com/
>>> + */
>>> +
>>> +/dts-v1/;
>>> +/plugin/;
>>> +
>>> +#include <dt-bindings/pwm/pwm.h>
>>> +#include <dt-bindings/gpio/gpio.h>
>>> +#include <dt-bindings/interrupt-controller/irq.h>
>>> +
>>> +&{/} {
>>> + display0 {
>>> + compatible = "rocktech,rk101ii01d-ct";
>>> + backlight = <&lcd_bl>;
>>> + enable-gpios = <&pca9555 8 GPIO_ACTIVE_HIGH>;
>>> + port {
>>> + lcd_in0: endpoint {
>>> + remote-endpoint = <&oldi_out0>;
>>> + };
>>> + };
>>> + };
>>> +
>>> + lcd_bl: backlight {
>>> + compatible = "pwm-backlight";
>>> + pwms = <&ecap0 0 50000 PWM_POLARITY_INVERTED>;
>>> + brightness-levels =
>>> + <0 32 64 96 128 160 192 224 255>;
>>> + default-brightness-level = <8>;
>>> + };
>>> +};
>>> +
>>> +&dss {
>>> + status = "okay";
>>> +};
>>> +
>>> +&dss_ports {
>>> + #address-cells = <1>;
>>> + #size-cells = <0>;
>>> +
>>> + port at 0 {
>>> + reg = <0>;
>>> +
>>> + oldi_out0: endpoint {
>>> + remote-endpoint = <&lcd_in0>;
>>> + };
>>> + };
>>> +};
>>> +
>>> +&main_i2c1 {
>>> + #address-cells = <1>;
>>> + #size-cells = <0>;
>>> +
>>> + gt928: touchscreen at 14 {
>>> + status = "okay";
>>> + compatible = "goodix,gt928";
>>> + reg = <0x14>;
>>> +
>>> + interrupt-parent = <&pca9554>;
>>> + interrupts = <3 IRQ_TYPE_EDGE_FALLING>;
>>> + touchscreen-size-x = <1280>;
>>> + touchscreen-size-y = <800>;
>>> +
>>> + reset-gpios = <&pca9555 9 GPIO_ACTIVE_HIGH>;
>>> + irq-gpios = <&pca9554 3 GPIO_ACTIVE_HIGH>;
>>> + };
>>> +};
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