Re: [PATCH 1/2] pinctrl-amd: enable IRQ for WACF2200 touchscreen on Lenovo Yoga 7 14AGP11

[Mario Limonciello <superm1@kernel.org>]

++

On 5/13/26 01:13, Hardik Prakash wrote:
> On Lenovo Yoga 7 14AGP11 (83TD), the WACF2200 touchscreen controller
> is wired via I2C2 (AMDI0010:02) with its interrupt on GPIO pin 157
> (confirmed via ACPI _CRS GpioInt decode). After amd_gpio_irq_init()
> clears all GPIO interrupts at boot, pin 157 is never re-enabled,
> preventing the touchscreen from signalling the driver.
> 
> Windows keeps GPIO 157 INTERRUPT_ENABLE (bit 11) and INTERRUPT_MASK
> (bit 12) set after initialisation. Add a DMI quirk to restore these
> bits after amd_gpio_irq_init() on this hardware.
> 
> Signed-off-by: Hardik Prakash <hardikprakash.official@gmail.com>
> Assisted-by: Claude:claude-sonnet-4-6
> Assisted-by: GPT-Codex:gpt-5.2-codex
> ---
>   drivers/pinctrl/pinctrl-amd.c | 35 +++++++++++++++++++++++++++++++++++
>   1 file changed, 35 insertions(+)
> 
> diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
> index e3128b0045d22..64315b0edf2a6 100644
> --- a/drivers/pinctrl/pinctrl-amd.c
> +++ b/drivers/pinctrl/pinctrl-amd.c
> @@ -26,6 +26,7 @@
>   #include <linux/interrupt.h>
>   #include <linux/bitops.h>
>   #include <linux/pinctrl/pinconf.h>
> +#include <linux/dmi.h>
>   #include <linux/pinctrl/pinconf-generic.h>
>   #include <linux/pinctrl/pinmux.h>
>   #include <linux/string_choices.h>
> @@ -39,6 +40,39 @@
>   static struct amd_gpio *pinctrl_dev;
>   #endif
>   
> +static const struct dmi_system_id amd_gpio_quirk_yoga7_14agp11[] = {
> +	{
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> +			DMI_MATCH(DMI_PRODUCT_NAME, "83TD"),
> +			DMI_MATCH(DMI_BOARD_NAME, "LNVNB161216"),
> +		},
> +	},
> +	{ }
> +};
> +
> +static void amd_gpio_apply_quirks(struct amd_gpio *gpio_dev)
> +{
> +	const unsigned int pin = 157; /* WACF2200 GpioInt per ACPI _CRS */
> +	unsigned long flags;
> +	u32 reg;
> +
> +	if (!dmi_check_system(amd_gpio_quirk_yoga7_14agp11))
> +		return;
> +	if (pin >= gpio_dev->gc.ngpio)
> +		return;
> +
> +	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
> +	reg = readl(gpio_dev->base + pin * 4);
> +	reg |= BIT(INTERRUPT_ENABLE_OFF) | BIT(INTERRUPT_MASK_OFF);
> +	writel(reg, gpio_dev->base + pin * 4);
> +	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
> +
> +	dev_info(&gpio_dev->pdev->dev,
> +		 "Enabled IRQ for GPIO %u (Yoga 7 14AGP11 touchscreen)\n",
> +		 pin);

I don't understand.  Our design is that the interrupt is disabled 
initially when driver loads (we don't trust state of the GPIO 
configuration pre-boot), and then when i2c-hid loads later it is 
re-enabled via amd_gpio_irq_enable().

Why isn't that flow working on this system?

> +}
> +
>   static int amd_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
>   {
>   	unsigned long flags;
> @@ -1219,6 +1253,7 @@ static int amd_gpio_probe(struct platform_device *pdev)
>   
>   	/* Disable and mask interrupts */
>   	amd_gpio_irq_init(gpio_dev);
> +	amd_gpio_apply_quirks(gpio_dev);
>   
>   	girq = &gpio_dev->gc.irq;
>   	gpio_irq_chip_set_chip(girq, &amd_gpio_irqchip);