On Tue, 14 Jan 2025 at 21:01, Thadeu Lima de Souza Cascardo
<cascardo@xxxxxxxxxx> wrote:
>
> This reverts commit 3dd075fe8ebbc6fcbf998f81a75b8c4b159a6195.
>
> Tomasz has reported that his device, Generalplus Technology Inc. 808 Camera,
> with ID 1b3f:2002, stopped being detected:
>
> $ ls -l /dev/video*
> zsh: no matches found: /dev/video*
> [ 7.230599] usb 3-2: Found multiple Units with ID 5
>
> This particular device is non-compliant, having both the Output Terminal
> and Processing Unit with ID 5. uvc_scan_fallback, though, is able to build
> a chain. However, when media elements are added and uvc_mc_create_links
> call uvc_entity_by_id, it will get the incorrect entity,
> media_create_pad_link will WARN, and it will fail to register the entities.
>
> In order to reinstate support for such devices in a timely fashion,
> reverting the fix for these warnings is appropriate. A proper fix that
> considers the existence of such non-compliant devices will be submitted in
> a later development cycle.
>
> Reported-by: Tomasz Sikora <sikora.tomus@xxxxxxxxx>
> Fixes: 3dd075fe8ebb ("media: uvcvideo: Require entities to have a non-zero unique ID")
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxx>
If we do not find another solution in a reasonable time I think we
should land this ASAP:
Reviewed-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> ---
> drivers/media/usb/uvc/uvc_driver.c | 70 ++++++++++++------------------
> 1 file changed, 27 insertions(+), 43 deletions(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
> index b3c8411dc05c..9febd2375636 100644
> --- a/drivers/media/usb/uvc/uvc_driver.c
> +++ b/drivers/media/usb/uvc/uvc_driver.c
> @@ -775,27 +775,14 @@ static const u8 uvc_media_transport_input_guid[16] =
> UVC_GUID_UVC_MEDIA_TRANSPORT_INPUT;
> static const u8 uvc_processing_guid[16] = UVC_GUID_UVC_PROCESSING;
>
> -static struct uvc_entity *uvc_alloc_new_entity(struct uvc_device *dev, u16 type,
> - u16 id, unsigned int num_pads,
> - unsigned int extra_size)
> +static struct uvc_entity *uvc_alloc_entity(u16 type, u16 id,
> + unsigned int num_pads, unsigned int extra_size)
> {
> struct uvc_entity *entity;
> unsigned int num_inputs;
> unsigned int size;
> unsigned int i;
>
> - /* Per UVC 1.1+ spec 3.7.2, the ID should be non-zero. */
> - if (id == 0) {
> - dev_err(&dev->udev->dev, "Found Unit with invalid ID 0.\n");
> - return ERR_PTR(-EINVAL);
> - }
> -
> - /* Per UVC 1.1+ spec 3.7.2, the ID is unique. */
> - if (uvc_entity_by_id(dev, id)) {
> - dev_err(&dev->udev->dev, "Found multiple Units with ID %u\n", id);
> - return ERR_PTR(-EINVAL);
> - }
> -
> extra_size = roundup(extra_size, sizeof(*entity->pads));
> if (num_pads)
> num_inputs = type & UVC_TERM_OUTPUT ? num_pads : num_pads - 1;
> @@ -805,7 +792,7 @@ static struct uvc_entity *uvc_alloc_new_entity(struct uvc_device *dev, u16 type,
> + num_inputs;
> entity = kzalloc(size, GFP_KERNEL);
> if (entity == NULL)
> - return ERR_PTR(-ENOMEM);
> + return NULL;
>
> entity->id = id;
> entity->type = type;
> @@ -917,10 +904,10 @@ static int uvc_parse_vendor_control(struct uvc_device *dev,
> break;
> }
>
> - unit = uvc_alloc_new_entity(dev, UVC_VC_EXTENSION_UNIT,
> - buffer[3], p + 1, 2 * n);
> - if (IS_ERR(unit))
> - return PTR_ERR(unit);
> + unit = uvc_alloc_entity(UVC_VC_EXTENSION_UNIT, buffer[3],
> + p + 1, 2*n);
> + if (unit == NULL)
> + return -ENOMEM;
>
> memcpy(unit->guid, &buffer[4], 16);
> unit->extension.bNumControls = buffer[20];
> @@ -1029,10 +1016,10 @@ static int uvc_parse_standard_control(struct uvc_device *dev,
> return -EINVAL;
> }
>
> - term = uvc_alloc_new_entity(dev, type | UVC_TERM_INPUT,
> - buffer[3], 1, n + p);
> - if (IS_ERR(term))
> - return PTR_ERR(term);
> + term = uvc_alloc_entity(type | UVC_TERM_INPUT, buffer[3],
> + 1, n + p);
> + if (term == NULL)
> + return -ENOMEM;
>
> if (UVC_ENTITY_TYPE(term) == UVC_ITT_CAMERA) {
> term->camera.bControlSize = n;
> @@ -1088,10 +1075,10 @@ static int uvc_parse_standard_control(struct uvc_device *dev,
> return 0;
> }
>
> - term = uvc_alloc_new_entity(dev, type | UVC_TERM_OUTPUT,
> - buffer[3], 1, 0);
> - if (IS_ERR(term))
> - return PTR_ERR(term);
> + term = uvc_alloc_entity(type | UVC_TERM_OUTPUT, buffer[3],
> + 1, 0);
> + if (term == NULL)
> + return -ENOMEM;
>
> memcpy(term->baSourceID, &buffer[7], 1);
>
> @@ -1110,10 +1097,9 @@ static int uvc_parse_standard_control(struct uvc_device *dev,
> return -EINVAL;
> }
>
> - unit = uvc_alloc_new_entity(dev, buffer[2], buffer[3],
> - p + 1, 0);
> - if (IS_ERR(unit))
> - return PTR_ERR(unit);
> + unit = uvc_alloc_entity(buffer[2], buffer[3], p + 1, 0);
> + if (unit == NULL)
> + return -ENOMEM;
>
> memcpy(unit->baSourceID, &buffer[5], p);
>
> @@ -1133,9 +1119,9 @@ static int uvc_parse_standard_control(struct uvc_device *dev,
> return -EINVAL;
> }
>
> - unit = uvc_alloc_new_entity(dev, buffer[2], buffer[3], 2, n);
> - if (IS_ERR(unit))
> - return PTR_ERR(unit);
> + unit = uvc_alloc_entity(buffer[2], buffer[3], 2, n);
> + if (unit == NULL)
> + return -ENOMEM;
>
> memcpy(unit->baSourceID, &buffer[4], 1);
> unit->processing.wMaxMultiplier =
> @@ -1162,10 +1148,9 @@ static int uvc_parse_standard_control(struct uvc_device *dev,
> return -EINVAL;
> }
>
> - unit = uvc_alloc_new_entity(dev, buffer[2], buffer[3],
> - p + 1, n);
> - if (IS_ERR(unit))
> - return PTR_ERR(unit);
> + unit = uvc_alloc_entity(buffer[2], buffer[3], p + 1, n);
> + if (unit == NULL)
> + return -ENOMEM;
>
> memcpy(unit->guid, &buffer[4], 16);
> unit->extension.bNumControls = buffer[20];
> @@ -1305,10 +1290,9 @@ static int uvc_gpio_parse(struct uvc_device *dev)
> return dev_err_probe(&dev->udev->dev, irq,
> "No IRQ for privacy GPIO\n");
>
> - unit = uvc_alloc_new_entity(dev, UVC_EXT_GPIO_UNIT,
> - UVC_EXT_GPIO_UNIT_ID, 0, 1);
> - if (IS_ERR(unit))
> - return PTR_ERR(unit);
> + unit = uvc_alloc_entity(UVC_EXT_GPIO_UNIT, UVC_EXT_GPIO_UNIT_ID, 0, 1);
> + if (!unit)
> + return -ENOMEM;
>
> unit->gpio.gpio_privacy = gpio_privacy;
> unit->gpio.irq = irq;
> --
> 2.34.1
>
--
Ricardo Ribalda
