RE: [PATCH v3 2/2] usb: webcam: Invalid size of Processing Unit Descriptor

From: Pawel Laszczak
Date: Mon Mar 15 2021 - 03:11:12 EST



Please ignore this one patch. I need to resend it. It causes compilation error.
Sorry for that.

>
>From: Pawel Laszczak <pawell@xxxxxxxxxxx>
>
>According with USB Device Class Definition for Video Device the
>Processing Unit Descriptor bLength should be 12 (10 + bmControlSize),
>but it has 11.
>
>Invalid length caused that Processing Unit Descriptor Test Video form
>CV tool failed. To fix this issue patch adds bmVideoStandards into
>uvc_processing_unit_descriptor structure.
>
>The bmVideoStandards field was added in UVC 1.1 and it wasn't part of
>UVC 1.0a.
>
>Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
>
>---
>Changelog:
>v3:
>- updated the commit message
>- added bmVideoStandard field to UVC gadget driver
>v2:
>- updated UVC_DT_PROCESSING_UNIT_SIZE macro
>
> drivers/usb/gadget/function/f_uvc.c | 1 +
> drivers/usb/gadget/legacy/webcam.c | 1 +
> include/uapi/linux/usb/video.h | 3 ++-
> 3 files changed, 4 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
>index 5d62720bb9e1..e3b0a79c8f01 100644
>--- a/drivers/usb/gadget/function/f_uvc.c
>+++ b/drivers/usb/gadget/function/f_uvc.c
>@@ -823,6 +823,7 @@ static struct usb_function_instance *uvc_alloc_inst(void)
> pd->bmControls[0] = 1;
> pd->bmControls[1] = 0;
> pd->iProcessing = 0;
>+ pd->bmVideoStandards = 0;
>
> od = &opts->uvc_output_terminal;
> od->bLength = UVC_DT_OUTPUT_TERMINAL_SIZE;
>diff --git a/drivers/usb/gadget/legacy/webcam.c b/drivers/usb/gadget/legacy/webcam.c
>index 3a61de4bb2b1..accb4dacf715 100644
>--- a/drivers/usb/gadget/legacy/webcam.c
>+++ b/drivers/usb/gadget/legacy/webcam.c
>@@ -125,6 +125,7 @@ static const struct uvc_processing_unit_descriptor uvc_processing = {
> .bmControls[0] = 1,
> .bmControls[1] = 0,
> .iProcessing = 0,
>+ .bmVideoStandrads = 0,
> };
>
> static const struct uvc_output_terminal_descriptor uvc_output_terminal = {
>diff --git a/include/uapi/linux/usb/video.h b/include/uapi/linux/usb/video.h
>index d854cb19c42c..bfdae12cdacf 100644
>--- a/include/uapi/linux/usb/video.h
>+++ b/include/uapi/linux/usb/video.h
>@@ -302,9 +302,10 @@ struct uvc_processing_unit_descriptor {
> __u8 bControlSize;
> __u8 bmControls[2];
> __u8 iProcessing;
>+ __u8 bmVideoStandards;
> } __attribute__((__packed__));
>
>-#define UVC_DT_PROCESSING_UNIT_SIZE(n) (9+(n))
>+#define UVC_DT_PROCESSING_UNIT_SIZE(n) (10+(n))
>
> /* 3.7.2.6. Extension Unit Descriptor */
> struct uvc_extension_unit_descriptor {
>--
>2.25.1

Regards,
Pawel Laszczak