2022-12-26 05:49:05

by Chen-Yu Tsai

[permalink] [raw]
Subject: [PATCH v2] media: hantro: Use core-generated bus_info value

The Hantro driver uses a hardcoded value for the bus_info field in the
media device and |struct v4l2_capability|. This worked well when there
was just one device. However with the iMX.8 series we are now seeing
two Hantro blocks on the same chip. The static bus_info is no longer
sufficient for differentiating devices.

Since commit f2d8b6917f3b ("media: v4l: ioctl: Set bus_info in
v4l_querycap()"), the V4L2 core provides a default value for the
bus_info field for platform and PCI devices. This value will match
the default value for media devices added by commit cef699749f37
("media: mc: Set bus_info in media_device_init()"). These defaults
are stable and device-specific.

Drop the static bus_info values from the hantro driver and use the
defaults.

Signed-off-by: Chen-Yu Tsai <[email protected]>
---
Changes since v1:
- Dropped unrelated Makefile change

drivers/media/platform/verisilicon/hantro_drv.c | 2 --
drivers/media/platform/verisilicon/hantro_v4l2.c | 2 --
2 files changed, 4 deletions(-)

diff --git a/drivers/media/platform/verisilicon/hantro_drv.c b/drivers/media/platform/verisilicon/hantro_drv.c
index 8cb4a68c9119..b0aeedae7b65 100644
--- a/drivers/media/platform/verisilicon/hantro_drv.c
+++ b/drivers/media/platform/verisilicon/hantro_drv.c
@@ -1050,8 +1050,6 @@ static int hantro_probe(struct platform_device *pdev)

vpu->mdev.dev = vpu->dev;
strscpy(vpu->mdev.model, DRIVER_NAME, sizeof(vpu->mdev.model));
- strscpy(vpu->mdev.bus_info, "platform: " DRIVER_NAME,
- sizeof(vpu->mdev.bus_info));
media_device_init(&vpu->mdev);
vpu->mdev.ops = &hantro_m2m_media_ops;
vpu->v4l2_dev.mdev = &vpu->mdev;
diff --git a/drivers/media/platform/verisilicon/hantro_v4l2.c b/drivers/media/platform/verisilicon/hantro_v4l2.c
index 2c7a805289e7..c1a116031013 100644
--- a/drivers/media/platform/verisilicon/hantro_v4l2.c
+++ b/drivers/media/platform/verisilicon/hantro_v4l2.c
@@ -142,8 +142,6 @@ static int vidioc_querycap(struct file *file, void *priv,

strscpy(cap->driver, vpu->dev->driver->name, sizeof(cap->driver));
strscpy(cap->card, vdev->name, sizeof(cap->card));
- snprintf(cap->bus_info, sizeof(cap->bus_info), "platform: %s",
- vpu->dev->driver->name);
return 0;
}

--
2.39.0.314.g84b9a713c41-goog


2022-12-26 22:00:24

by Ezequiel Garcia

[permalink] [raw]
Subject: Re: [PATCH v2] media: hantro: Use core-generated bus_info value

On Mon, Dec 26, 2022 at 01:26:06PM +0800, Chen-Yu Tsai wrote:
> The Hantro driver uses a hardcoded value for the bus_info field in the
> media device and |struct v4l2_capability|. This worked well when there
> was just one device. However with the iMX.8 series we are now seeing
> two Hantro blocks on the same chip. The static bus_info is no longer
> sufficient for differentiating devices.
>
> Since commit f2d8b6917f3b ("media: v4l: ioctl: Set bus_info in
> v4l_querycap()"), the V4L2 core provides a default value for the
> bus_info field for platform and PCI devices. This value will match
> the default value for media devices added by commit cef699749f37
> ("media: mc: Set bus_info in media_device_init()"). These defaults
> are stable and device-specific.
>
> Drop the static bus_info values from the hantro driver and use the
> defaults.
>
> Signed-off-by: Chen-Yu Tsai <[email protected]>

Makes sense.

Reviewed-by: Ezequiel Garcia <[email protected]>

Thanks!


> ---
> Changes since v1:
> - Dropped unrelated Makefile change
>
> drivers/media/platform/verisilicon/hantro_drv.c | 2 --
> drivers/media/platform/verisilicon/hantro_v4l2.c | 2 --
> 2 files changed, 4 deletions(-)
>
> diff --git a/drivers/media/platform/verisilicon/hantro_drv.c b/drivers/media/platform/verisilicon/hantro_drv.c
> index 8cb4a68c9119..b0aeedae7b65 100644
> --- a/drivers/media/platform/verisilicon/hantro_drv.c
> +++ b/drivers/media/platform/verisilicon/hantro_drv.c
> @@ -1050,8 +1050,6 @@ static int hantro_probe(struct platform_device *pdev)
>
> vpu->mdev.dev = vpu->dev;
> strscpy(vpu->mdev.model, DRIVER_NAME, sizeof(vpu->mdev.model));
> - strscpy(vpu->mdev.bus_info, "platform: " DRIVER_NAME,
> - sizeof(vpu->mdev.bus_info));
> media_device_init(&vpu->mdev);
> vpu->mdev.ops = &hantro_m2m_media_ops;
> vpu->v4l2_dev.mdev = &vpu->mdev;
> diff --git a/drivers/media/platform/verisilicon/hantro_v4l2.c b/drivers/media/platform/verisilicon/hantro_v4l2.c
> index 2c7a805289e7..c1a116031013 100644
> --- a/drivers/media/platform/verisilicon/hantro_v4l2.c
> +++ b/drivers/media/platform/verisilicon/hantro_v4l2.c
> @@ -142,8 +142,6 @@ static int vidioc_querycap(struct file *file, void *priv,
>
> strscpy(cap->driver, vpu->dev->driver->name, sizeof(cap->driver));
> strscpy(cap->card, vdev->name, sizeof(cap->card));
> - snprintf(cap->bus_info, sizeof(cap->bus_info), "platform: %s",
> - vpu->dev->driver->name);
> return 0;
> }
>
> --
> 2.39.0.314.g84b9a713c41-goog
>