Some Alder Lake systems, such as those using the PixArt I2C touchpad (PIXA3848),
reuse GPIO IP blocks similar to Tiger Lake. As a result, enabling
CONFIG_PINCTRL_TIGERLAKE may be required for proper I2C device detection.

Document this in the Kconfig help text to assist users encountering this issue.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=220056
Signed-off-by: Ariel Simulevski <ariel@simulevski.at>
---
 drivers/pinctrl/intel/Kconfig | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/pinctrl/intel/Kconfig b/drivers/pinctrl/intel/Kconfig
index 248c2e558ff3..b8e1436b04f7 100644
--- a/drivers/pinctrl/intel/Kconfig
+++ b/drivers/pinctrl/intel/Kconfig
@@ -54,6 +54,11 @@ config PINCTRL_ALDERLAKE
 	  This pinctrl driver provides an interface that allows configuring
 	  of Intel Alder Lake PCH pins and using them as GPIOs.
 
+	  Note: On some Alder Lake platforms, including systems with
+	  the PixArt I2C touchpad (PIXA3848), the hardware reuses
+	  Tiger Lake style GPIO blocks. For proper device detection,
+	  enabling CONFIG_PINCTRL_TIGERLAKE may be necessary.
+
 config PINCTRL_BROXTON
 	tristate "Intel Broxton pinctrl and GPIO driver"
 	select PINCTRL_INTEL
-- 
2.49.0

On Tue, Apr 29, 2025 at 2:56 AM Ariel Simulevski <ariel@simulevski.at> wrote:

Thank you for the patch. My comments below.

First of all, the Subject should start with: "pinctrl: tigerlake: ..."

> Some Alder Lake systems, such as those using the PixArt I2C touchpad (PIXA3848),
> reuse GPIO IP blocks similar to Tiger Lake. As a result, enabling
> CONFIG_PINCTRL_TIGERLAKE may be required for proper I2C device detection.
>
> Document this in the Kconfig help text to assist users encountering this issue.

It's all nice, but can be written in much simpler way:

"Some users may be confused on what to choose to support their chipsets,
Document supported SoCs and PCHs by the driver in the Kconfig help text."

Or something like that.

(In other words the "touchpad", "some systems", etc are unneeded
details. It may be other users who have different issues, you need to
cover all of them.)

> Link: https://bugzilla.kernel.org/show_bug.cgi?id=220056

> Signed-off-by: Ariel Simulevski <ariel@simulevski.at>

Reported-by: ... ?

...

> @@ -54,6 +54,11 @@ config PINCTRL_ALDERLAKE
>           This pinctrl driver provides an interface that allows configuring
>           of Intel Alder Lake PCH pins and using them as GPIOs.
>
> +         Note: On some Alder Lake platforms, including systems with
> +         the PixArt I2C touchpad (PIXA3848), the hardware reuses
> +         Tiger Lake style GPIO blocks. For proper device detection,
> +         enabling CONFIG_PINCTRL_TIGERLAKE may be necessary.
> +

This is too narrow and too detailed, nobody needs to know this. Just
list the platforms the driver supports (take the example from the
existing list, i.e. INTEL_PLATFORM):
"Currently the following Intel SoCs / platforms require this to be functional:
  — Tiger Lake (all variants) // needs to be double checked
  — Alder Lake-P
"

-- 
With Best Regards,
Andy Shevchenko