[PATCH v2] drm/amd/amdgpu: Add GPIO resources required for amdisp

[Mario Limonciello]

On 5/15/2025 5:16 PM, Pratap Nirujogi wrote:
> ISP is a child device to GFX, and its device specific information
> is not available in ACPI. Adding the 2 GPIO resources required for
> ISP_v4_1_1 in amdgpu_isp driver.
> 
> - GPIO 0 to allow sensor driver to enable and disable sensor module.
> - GPIO 85 to allow ISP driver to enable and disable ISP RGB streaming mode.
> 
> Signed-off-by: Pratap Nirujogi <pratap.nirujogi at amd.com>
> ---
> Changes v1 -> v2:
> 
> * Use fixed "isp_dev_hid[ACPI_ID_LEN]" instead of allocating using devm_kzalloc()
> * Instead of "pointer to pointer" use "pointer to array" type arg in amdgpu_acpi_get_isp4_dev_hid()
> * Include error code in the debug statement
> 
>   drivers/gpu/drm/amd/amdgpu/amdgpu.h      |  2 ++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c | 29 ++++++++++++++++++++++
>   drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c  | 31 ++++++++++++++++++++++++
>   3 files changed, 62 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index cc26cf1bd843..2aa7e89a190e 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -1657,10 +1657,12 @@ static inline void amdgpu_acpi_get_backlight_caps(struct amdgpu_dm_backlight_cap
>   bool amdgpu_acpi_is_s3_active(struct amdgpu_device *adev);
>   bool amdgpu_acpi_is_s0ix_active(struct amdgpu_device *adev);
>   void amdgpu_choose_low_power_state(struct amdgpu_device *adev);
> +int amdgpu_acpi_get_isp4_dev_hid(u8 (*hid)[ACPI_ID_LEN]);
>   #else
>   static inline bool amdgpu_acpi_is_s0ix_active(struct amdgpu_device *adev) { return false; }
>   static inline bool amdgpu_acpi_is_s3_active(struct amdgpu_device *adev) { return false; }
>   static inline void amdgpu_choose_low_power_state(struct amdgpu_device *adev) { }
> +static int amdgpu_acpi_get_isp4_dev_hid(u8 (*hid)[ACPI_ID_LEN]) { }
>   #endif
>   
>   void amdgpu_register_gpu_instance(struct amdgpu_device *adev);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> index b7f8f2ff143d..c39d3a09cd04 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> @@ -1551,4 +1551,33 @@ void amdgpu_choose_low_power_state(struct amdgpu_device *adev)
>   		adev->in_s3 = true;
>   }
>   
> +static const struct acpi_device_id isp_sensor_ids[] = {
> +	{ "OMNI5C10" },
> +	{ }
> +};
> +
> +static int isp_match_acpi_device_ids(struct device *dev, const void *data)
> +{
> +	return acpi_match_device(data, dev) ? 1 : 0;
> +}
> +
> +int amdgpu_acpi_get_isp4_dev_hid(u8 (*hid)[ACPI_ID_LEN])
> +{
> +	struct acpi_device *acpi_pdev;
> +	struct device *pdev;
> +
> +	pdev = bus_find_device(&platform_bus_type, NULL, isp_sensor_ids,
> +			       isp_match_acpi_device_ids);
> +	if (!pdev)
> +		return -EINVAL;
> +
> +	acpi_pdev = ACPI_COMPANION(pdev);
> +	if (acpi_pdev)
> +		strscpy(*hid, acpi_device_hid(acpi_pdev));
> +
> +	put_device(pdev);
> +
> +	return 0;
> +}
> +
>   #endif /* CONFIG_SUSPEND */
> diff --git a/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c b/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
> index 69dd92f6e86d..574880d67009 100644
> --- a/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
> +++ b/drivers/gpu/drm/amd/amdgpu/isp_v4_1_1.c
> @@ -25,6 +25,7 @@
>    *
>    */
>   
> +#include <linux/gpio/machine.h>
>   #include "amdgpu.h"
>   #include "isp_v4_1_1.h"
>   
> @@ -39,15 +40,45 @@ static const unsigned int isp_4_1_1_int_srcid[MAX_ISP411_INT_SRC] = {
>   	ISP_4_1__SRCID__ISP_RINGBUFFER_WPT16
>   };
>   
> +static struct gpiod_lookup_table isp_gpio_table = {
> +	.dev_id = "amd_isp_capture",
> +	.table = {
> +		GPIO_LOOKUP("AMDI0030:00", 85, "enable_isp", GPIO_ACTIVE_HIGH),
> +		{ }
> +	},
> +};
> +
> +static struct gpiod_lookup_table isp_sensor_gpio_table = {
> +	.dev_id = "i2c-ov05c10",
> +	.table = {
> +		GPIO_LOOKUP("amdisp-pinctrl", 0, "enable", GPIO_ACTIVE_HIGH),
> +		{ }
> +	},
> +};
> +
>   static int isp_v4_1_1_hw_init(struct amdgpu_isp *isp)
>   {
>   	struct amdgpu_device *adev = isp->adev;
>   	int idx, int_idx, num_res, r;
> +	u8 isp_dev_hid[ACPI_ID_LEN];

I don't think this is going to happen in practice, but because this 
isn't initialized you have a case that the ACPI_COMPANION() isn't found 
and thus amdgpu_acpi_get_isp4_dev_hid() returns 0 and there is garbage 
in isp_dev_hid.

I think it's best for amdgpu_acpi_get_isp4_dev_hid() to check acpi_pdev 
for being NULL and return -ENODEV to avoid this risk or isp_dev_hid to 
be initialized to NULL.

>   	u64 isp_base;
>   
>   	if (adev->rmmio_size == 0 || adev->rmmio_size < 0x5289)
>   		return -EINVAL;
>   
> +	r = amdgpu_acpi_get_isp4_dev_hid(&isp_dev_hid);
> +	if (r) {
> +		drm_dbg(&adev->ddev, "Invalid isp platform detected (%d)", r);
> +		/* allow GPU init to progress */
> +		return 0;
> +	}
> +
> +	/* add GPIO resources required for OMNI5C10 sensor */
> +	if (!strcmp("OMNI5C10", isp_dev_hid)) {
> +		gpiod_add_lookup_table(&isp_gpio_table);
> +		gpiod_add_lookup_table(&isp_sensor_gpio_table);
> +	}
> +
>   	isp_base = adev->rmmio_base;
>   
>   	isp->isp_cell = kcalloc(3, sizeof(struct mfd_cell), GFP_KERNEL);