Re: [PATCH 1/2] arm64: dts: ti: Add overlay for OLDI-LCD1EVM Display and touch screen
From: Andrew Davis
Date: Tue Apr 25 2023 - 13:45:28 EST
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@xxxxxx>
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@xxxxxx>
Signed-off-by: Nikhil Devshatwar <nikhil.nd@xxxxxx>
[abhatia1@xxxxxx: Make syntax changes to support 6.1 DTSO format]
Signed-off-by: Aradhya Bhatia <a-bhatia1@xxxxxx>
---
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@0 {
+ reg = <0>;
+
+ oldi_out0: endpoint {
+ remote-endpoint = <&lcd_in0>;
+ };
+ };
+};
+
+&main_i2c1 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ gt928: touchscreen@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>;
+ };
+};