From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: chenchangcheng <ccc194101@163.com>
Cc: hdegoede@redhat.com, mchehab@kernel.org,
linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
chenchangcheng <chenchangcheng@kylinos.cn>
Subject: Re: [PATCH v6] media: uvcvideo: Fix bandwidth issue for Alcor camera
Date: Thu, 10 Apr 2025 05:07:15 +0300 [thread overview]
Message-ID: <20250410020715.GA15367@pendragon.ideasonboard.com> (raw)
In-Reply-To: <20250324022120.216923-1-ccc194101@163.com>
On Mon, Mar 24, 2025 at 10:21:20AM +0800, chenchangcheng wrote:
> From: chenchangcheng <chenchangcheng@kylinos.cn>
>
> Some broken device return wrong dwMaxPayloadTransferSize fields,
> as follows:
> [ 218.632537] [pid:20427,cpu6,guvcview,8]uvcvideo: Device requested 2752512 B/frame bandwidth.
> [ 218.632598] [pid:20427,cpu6,guvcview,9]uvcvideo: No fast enough alt setting for requested bandwidth.
>
> The maximum packet size of the device is 3 * 1024, according to the
> logs above, the device needs to apply for a bandwidth of 0x2a0000.
>
> Bus 001 Device 008: ID 1b17:6684 Alcor Corp. Slave camera
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.00
> bDeviceClass 239 Miscellaneous Device
> bDeviceSubClass 2
> bDeviceProtocol 1 Interface Association
> bMaxPacketSize0 64
> idVendor 0x1b17
> idProduct 0x6684
> bcdDevice 1.05
> iManufacturer 1 Alcor Corp.
> iProduct 2 Slave camera
> iSerial 0
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 0x02ad
> bNumInterfaces 2
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0x80
> (Bus Powered)
> MaxPower 200mA
> Interface Association:
> bLength 8
> bDescriptorType 11
> bFirstInterface 0
> bInterfaceCount 2
> bFunctionClass 14 Video
> bFunctionSubClass 3 Video Interface Collection
> bFunctionProtocol 0
> iFunction 4 Slave camera
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 1
> bInterfaceClass 14 Video
> bInterfaceSubClass 1 Video Control
> bInterfaceProtocol 0
> iInterface 4 Slave camera
> VideoControl Interface Descriptor:
>
> ....
>
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0010 1x 16 bytes
> bInterval 7
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 0
> bNumEndpoints 0
> bInterfaceClass 14 Video
> bInterfaceSubClass 2 Video Streaming
> bInterfaceProtocol 0
> iInterface 0
> VideoStreaming Interface Descriptor:
> bLength 14
> bDescriptorType 36
> bDescriptorSubtype 1 (INPUT_HEADER)
> bNumFormats 1
> wTotalLength 0x01ef
> bEndPointAddress 130
> bmInfo 0
> bTerminalLink 3
> bStillCaptureMethod 2
> bTriggerSupport 1
> bTriggerUsage 0
> bControlSize 1
> bmaControls( 0) 0
> VideoStreaming Interface Descriptor:
> bLength 11
> bDescriptorType 36
> bDescriptorSubtype 6 (FORMAT_MJPEG)
> bFormatIndex 1
> bNumFrameDescriptors 9
> bFlags 1
> Fixed-size samples: Yes
> bDefaultFrameIndex 1
> bAspectRatioX 0
> bAspectRatioY 0
> bmInterlaceFlags 0x00
> Interlaced stream or variable: No
> Fields per frame: 1 fields
> Field 1 first: No
> Field pattern: Field 1 only
> bCopyProtect 0
> VideoStreaming Interface Descriptor:
> bLength 50
> bDescriptorType 36
> bDescriptorSubtype 7 (FRAME_MJPEG)
> bFrameIndex 1
> bmCapabilities 0x00
> Still image unsupported
> wWidth 1920
> wHeight 1080
> dwMinBitRate 248832000
> dwMaxBitRate 1492992000
> dwMaxVideoFrameBufferSize 6220800
> dwDefaultFrameInterval 333333
> bFrameIntervalType 6
> dwFrameInterval( 0) 333333
> dwFrameInterval( 1) 400000
> dwFrameInterval( 2) 500000
> dwFrameInterval( 3) 666666
> dwFrameInterval( 4) 1000000
> dwFrameInterval( 5) 2000000
>
> ......
>
> VideoStreaming Interface Descriptor:
> bLength 42
> bDescriptorType 36
> bDescriptorSubtype 3 (STILL_IMAGE_FRAME)
> bEndpointAddress 0
> bNumImageSizePatterns 9
> wWidth( 0) 1920
> wHeight( 0) 1080
> wWidth( 1) 2048
> wHeight( 1) 1536
> wWidth( 2) 1280
> wHeight( 2) 720
> wWidth( 3) 2592
> wHeight( 3) 1944
> wWidth( 4) 1280
> wHeight( 4) 1024
> wWidth( 5) 1280
> wHeight( 5) 960
> wWidth( 6) 1600
> wHeight( 6) 1200
> wWidth( 7) 800
> wHeight( 7) 600
> wWidth( 8) 640
> wHeight( 8) 480
> bNumCompressionPatterns 0
> VideoStreaming Interface Descriptor:
> bLength 6
> bDescriptorType 36
> bDescriptorSubtype 13 (COLORFORMAT)
> bColorPrimaries 1 (BT.709,sRGB)
> bTransferCharacteristics 1 (BT.709)
> bMatrixCoefficients 4 (SMPTE 170M (BT.601))
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 1
> bNumEndpoints 1
> bInterfaceClass 14 Video
> bInterfaceSubClass 2 Video Streaming
> bInterfaceProtocol 0
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 5
> Transfer Type Isochronous
> Synch Type Asynchronous
> Usage Type Data
> wMaxPacketSize 0x1400 3x 1024 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 2
> bNumEndpoints 1
> bInterfaceClass 14 Video
> bInterfaceSubClass 2 Video Streaming
> bInterfaceProtocol 0
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 5
> Transfer Type Isochronous
> Synch Type Asynchronous
> Usage Type Data
> wMaxPacketSize 0x0b84 2x 900 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 3
> bNumEndpoints 1
> bInterfaceClass 14 Video
> bInterfaceSubClass 2 Video Streaming
> bInterfaceProtocol 0
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 5
> Transfer Type Isochronous
> Synch Type Asynchronous
> Usage Type Data
> wMaxPacketSize 0x0c00 2x 1024 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 4
> bNumEndpoints 1
> bInterfaceClass 14 Video
> bInterfaceSubClass 2 Video Streaming
> bInterfaceProtocol 0
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 5
> Transfer Type Isochronous
> Synch Type Asynchronous
> Usage Type Data
> wMaxPacketSize 0x0c00 2x 1024 bytes
> bInterval 1
> Device Qualifier (for other device speed):
> bLength 10
> bDescriptorType 6
> bcdUSB 2.00
> bDeviceClass 239 Miscellaneous Device
> bDeviceSubClass 2
> bDeviceProtocol 1 Interface Association
> bMaxPacketSize0 64
> bNumConfigurations 1
> Device Status: 0x0000
> (Bus Powered)
>
> Signed-off-by: chenchangcheng <chenchangcheng@kylinos.cn>
> ---
> drivers/media/usb/uvc/uvc_driver.c | 9 +++++++++
> drivers/media/usb/uvc/uvc_video.c | 10 ++++++++++
> drivers/media/usb/uvc/uvcvideo.h | 1 +
> 3 files changed, 20 insertions(+)
>
> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
> index deadbcea5e22..9b1dedf9773b 100644
> --- a/drivers/media/usb/uvc/uvc_driver.c
> +++ b/drivers/media/usb/uvc/uvc_driver.c
> @@ -3023,6 +3023,15 @@ static const struct usb_device_id uvc_ids[] = {
> .bInterfaceSubClass = 1,
> .bInterfaceProtocol = 0,
> .driver_info = UVC_INFO_QUIRK(UVC_QUIRK_STATUS_INTERVAL) },
> + /* Alcor Corp. Slave camera */
> + { .match_flags = USB_DEVICE_ID_MATCH_DEVICE
> + | USB_DEVICE_ID_MATCH_INT_INFO,
> + .idVendor = 0x1b17,
> + .idProduct = 0x6684,
> + .bInterfaceClass = USB_CLASS_VIDEO,
> + .bInterfaceSubClass = 1,
> + .bInterfaceProtocol = 0,
> + .driver_info = UVC_INFO_QUIRK(UVC_QUIRK_OVERFLOW_BANDWIDTH) },
> /* MSI StarCam 370i */
> { .match_flags = USB_DEVICE_ID_MATCH_DEVICE
> | USB_DEVICE_ID_MATCH_INT_INFO,
> diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
> index e3567aeb0007..56f23c363870 100644
> --- a/drivers/media/usb/uvc/uvc_video.c
> +++ b/drivers/media/usb/uvc/uvc_video.c
> @@ -262,6 +262,16 @@ static void uvc_fixup_video_ctrl(struct uvc_streaming *stream,
>
> ctrl->dwMaxPayloadTransferSize = bandwidth;
> }
> +
> + if (stream->intf->num_altsetting > 1 &&
> + ctrl->dwMaxPayloadTransferSize > stream->maxpsize &&
> + stream->dev->quirks & UVC_QUIRK_OVERFLOW_BANDWIDTH) {
> + dev_warn(&stream->intf->dev,
> + "the max payload transmission size (%d) exceededs the size of the ep max packet (%d). Using the max size.\n",
> + ctrl->dwMaxPayloadTransferSize,
> + stream->maxpsize);
> + ctrl->dwMaxPayloadTransferSize = stream->maxpsize;
If the requested bandwidth exceed the maximum the device can use, it's
clearly a firmware bug. Why do we need a quirk for this, can't we use
the maximum usable bandwidth in that case, regardless of the particular
device ?
> + }
> }
>
> static size_t uvc_video_ctrl_size(struct uvc_streaming *stream)
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 5e388f05f3fc..8b43d725c259 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -77,6 +77,7 @@
> #define UVC_QUIRK_DISABLE_AUTOSUSPEND 0x00008000
> #define UVC_QUIRK_INVALID_DEVICE_SOF 0x00010000
> #define UVC_QUIRK_MJPEG_NO_EOF 0x00020000
> +#define UVC_QUIRK_OVERFLOW_BANDWIDTH 0x00040000
>
> /* Format flags */
> #define UVC_FMT_FLAG_COMPRESSED 0x00000001
>
> base-commit: 4701f33a10702d5fc577c32434eb62adde0a1ae1
--
Regards,
Laurent Pinchart
next prev parent reply other threads:[~2025-04-10 2:07 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-24 2:21 [PATCH v6] media: uvcvideo: Fix bandwidth issue for Alcor camera chenchangcheng
2025-04-07 13:35 ` Hans de Goede
2025-04-07 15:48 ` Ricardo Ribalda
2025-04-08 1:26 ` 自己
2025-04-10 2:07 ` Laurent Pinchart [this message]
2025-04-10 5:32 ` Ricardo Ribalda
2025-04-10 9:14 ` Laurent Pinchart
2025-04-10 10:02 ` Ricardo Ribalda
2025-04-10 13:11 ` Laurent Pinchart
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