Re: [PATCH v1 1/2] platform/x86: int3472: add hpd pin support

Hans de Goede
2025-04-11T08:33:58Z

Hi,

On 11-Apr-25 10:23 AM, Dongcheng Yan wrote:
> Typically HDMI to MIPI CSI-2 bridges have a pin to signal image data is
> being received. On the host side this is wired to a GPIO for polling or
> interrupts. This includes the Lontium HDMI to MIPI CSI-2 bridges
> lt6911uxe and lt6911uxc.
>
> The GPIO "hpd" is used already by other HDMI to CSI-2 bridges, use it
> here as well.
>
> Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> ---
> drivers/platform/x86/intel/int3472/common.h | 1 +
> drivers/platform/x86/intel/int3472/discrete.c | 6 ++++++
> 2 files changed, 7 insertions(+)
>
> diff --git a/drivers/platform/x86/intel/int3472/common.h b/drivers/platform/x86/intel/int3472/common.h
> index 145dec66df64..db4cd3720e24 100644
> --- a/drivers/platform/x86/intel/int3472/common.h
> +++ b/drivers/platform/x86/intel/int3472/common.h
> @@ -22,6 +22,7 @@
> #define INT3472_GPIO_TYPE_POWER_ENABLE 0x0b
> #define INT3472_GPIO_TYPE_CLK_ENABLE 0x0c
> #define INT3472_GPIO_TYPE_PRIVACY_LED 0x0d
> +#define INT3472_GPIO_TYPE_HOTPLUG_DETECT 0x13
>
> #define INT3472_PDEV_MAX_NAME_LEN 23
> #define INT3472_MAX_SENSOR_GPIOS 3
> diff --git a/drivers/platform/x86/intel/int3472/discrete.c b/drivers/platform/x86/intel/int3472/discrete.c
> index 30ff8f3ea1f5..28d41b1b3809 100644
> --- a/drivers/platform/x86/intel/int3472/discrete.c
> +++ b/drivers/platform/x86/intel/int3472/discrete.c
> @@ -186,6 +186,10 @@ static void int3472_get_con_id_and_polarity(struct acpi_device *adev, u8 *type,
> *con_id = "privacy-led";
> *gpio_flags = GPIO_ACTIVE_HIGH;
> break;
> + case INT3472_GPIO_TYPE_HOTPLUG_DETECT:
> + *con_id = "hpd";
> + *gpio_flags = GPIO_LOOKUP_FLAGS_DEFAULT;

This looks wrong, we really need to clearly provide a polarity
here since the ACPI GPIO resources do not provide one.

Regards,

Hans

> + break;
> case INT3472_GPIO_TYPE_POWER_ENABLE:
> *con_id = "power-enable";
> *gpio_flags = GPIO_ACTIVE_HIGH;
> @@ -212,6 +216,7 @@ static void int3472_get_con_id_and_polarity(struct acpi_device *adev, u8 *type,
> * 0x0b Power enable
> * 0x0c Clock enable
> * 0x0d Privacy LED
> + * 0x13 Hotplug detect
> *
> * There are some known platform specific quirks where that does not quite
> * hold up; for example where a pin with type 0x01 (Power down) is mapped to
> @@ -281,6 +286,7 @@ static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
> switch (type) {
> case INT3472_GPIO_TYPE_RESET:
> case INT3472_GPIO_TYPE_POWERDOWN:
> + case INT3472_GPIO_TYPE_HOTPLUG_DETECT:
> ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, con_id, gpio_flags);
> if (ret)
> err_msg = "Failed to map GPIO pin to sensor\n";
>
> base-commit: 01c6df60d5d4ae00cd5c1648818744838bba7763