Modify I2S pin as GPIO

[Ray0420]

Hello,

Because we don’t have enough GPIO for use, we went to use the four pins of I2S0(We don’t need to use this specific function).
I find the pin mapping in this file “Jetson_TX1_Generic_Customer_Pinmux_Customer_Release.xlsm” and the four pins were mapping to GPIO_PB00 ~ GPIO_PB03, now I have two question as below:
1.I could find the TK1 GPIO definition in arch/arm/mach-tegra/gpio-names.h, but where is the TX1?
I try to control the I2S0_SDIN(GPIO3_PB01) as GPIO9 which TK1 defined, but this pin couldn’t output what I expect.
2.Continuous the first question, should I modify the setting for I2S0 which may be set in bootloader or device tree.

Thanks

[ShaneCCC]

1. The gpio-names.h only some define for the readable purpose if you need it you can still modify/include it.
2. You need to modify the DT for your request. Like below is modify i2s1 to gpio PB01

diff --git a/arch/arm64/boot/dts/tegra210-platforms/tegra210-jetson-cv-pinmux-p2597-2180-a00.dtsi b/arch/arm64/boot/dts/tegra210-platforms/tegra210-jetson-cv-pinmux-p2597-2180-a00.dtsi
index 44dcf7e..707a472 100644
--- a/arch/arm64/boot/dts/tegra210-platforms/tegra210-jetson-cv-pinmux-p2597-2180-a00.dtsi
+++ b/arch/arm64/boot/dts/tegra210-platforms/tegra210-jetson-cv-pinmux-p2597-2180-a00.dtsi
@@ -47,7 +47,7 @@
 
                        dap1_din_pb1 {
                                nvidia,pins = "dap1_din_pb1";
-                               nvidia,function = "i2s1";
+                               nvidia,function = "rsvd1";
                                nvidia,pull = <TEGRA_PIN_PULL_NONE>;
                                nvidia,tristate = <TEGRA_PIN_DISABLE>;
                                nvidia,enable-input = <TEGRA_PIN_ENABLE>;

[Ray0420]

Hi ShaneCCC,

Thanks for your response.
What’s the meaning of revd1? Is there any document to map such define?

Thanks

[ShaneCCC]

You can check the pimux table. You can see the SFIO0, SFIO1, SFIO2, SFIO3 and for the GP01 ball name DAP1_DIN config as GPIO you need to config this pin to first empty field.

External Media