The Dino-Lite cameras are equipped with LED lights that can be switched
on and off by setting a proprietary control. For this control, the
camera reports a length of 1 byte, but actually the value set by the
original Windows driver is 3 byte long. This makes it impossible to
toggle the camera lights from uvcvideo, as the length from GET_LEN is
trusted as being the right one.
This is to make GET_LEN indicate a length of 3 instead of 1 for this
specific device.
Signed-off-by: Alexandre Macabies <web+oss@xxxxxxxxxxx>
---
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 28b91b7d7..17689a242 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -2734,6 +2734,15 @@ static const struct usb_device_id uvc_ids[] = {
.bInterfaceSubClass = 1,
.bInterfaceProtocol = 0,
.driver_info = UVC_QUIRK_FORCE_Y8 },
+ /* Dino-Lite Premier AM4111T */
+ { .match_flags = USB_DEVICE_ID_MATCH_DEVICE
+ | USB_DEVICE_ID_MATCH_INT_INFO,
+ .idVendor = 0xa168,
+ .idProduct = 0x0870,
+ .bInterfaceClass = USB_CLASS_VIDEO,
+ .bInterfaceSubClass = 1,
+ .bInterfaceProtocol = 0,
+ .driver_info = UVC_QUIRK_LIGHT_CTRL_LEN },
/* Generic USB Video Class */
{ USB_INTERFACE_INFO(USB_CLASS_VIDEO, 1, UVC_PC_PROTOCOL_UNDEFINED) },
{ USB_INTERFACE_INFO(USB_CLASS_VIDEO, 1, UVC_PC_PROTOCOL_15) },
diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
index fb86d6af3..702bf03c7 100644
--- a/drivers/media/usb/uvc/uvc_video.c
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -83,6 +83,16 @@ int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
return -EIO;
}
+ /* The Dino-Lite Premier camera lies about a specific query length:
+ * control 3 unit 4 (LED light on/off) expects a 3 byte payload but
+ * the camera reports only 1 byte when queried for GET_LEN.
+ */
+ if ((dev->quirks & UVC_QUIRK_LIGHT_CTRL_LEN) && query == UVC_GET_LEN
+ && cs == 3 && unit == 4 && size == 2) {
+ put_unaligned_le16(3, data);
+ return 0;
+ }
+
return 0;
}
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 05398784d..bb6a74920 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -186,6 +186,7 @@
#define UVC_QUIRK_RESTRICT_FRAME_RATE 0x00000200
#define UVC_QUIRK_RESTORE_CTRLS_ON_INIT 0x00000400
#define UVC_QUIRK_FORCE_Y8 0x00000800
+#define UVC_QUIRK_LIGHT_CTRL_LEN 0x00001000
/* Format flags */
#define UVC_FMT_FLAG_COMPRESSED 0x00000001
--
2.15.1
