This patch depends on the previous patch in this series:
[PATCH 2/4] usb: gadget: composite: add function to increment
delayed_status
The completion of the usb status phase from uvc_function_set_alt needs
to be delayed until uvc_v4l2_streamon/off. This is currently done by
uvc_function_set_alt returning USB_GADGET_DELAYED_STATUS and
composite_setup detecting this to increment cdev->delayed_status.
However, if uvc_v4l2_streamon/off is called in between this return and
increment, uvc_function_setup_continue within uvc_v4l2_streamon/off will
WARN that cdev->delayed_status is zero.
To fix this, use usb_composite_setup_delay to increment
cdev->delayed_status, and then return 0 so that composite_setup doesn't
increment cdev->delayed_status again.
Signed-off-by: Paul Elder <paul.el...@pitt.edu>
---
drivers/usb/gadget/function/f_uvc.c | 13 ++++++++++++-
drivers/usb/gadget/function/uvc_v4l2.c | 2 ++
2 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/function/f_uvc.c
b/drivers/usb/gadget/function/f_uvc.c
index 9b63b28a1ee3..3324d36e809c 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -334,6 +334,8 @@ uvc_function_set_alt(struct usb_function *f, unsigned
interface, unsigned alt)
uvc->state = UVC_STATE_STOPPING;
+ usb_composite_setup_delay(cdev);
+
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_STREAMOFF;
v4l2_event_queue(&uvc->vdev, &v4l2_event);
@@ -358,10 +360,19 @@ uvc_function_set_alt(struct usb_function *f, unsigned
interface, unsigned alt)
uvc->state = UVC_STATE_STARTING;
+ usb_composite_setup_delay(cdev);
+
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_STREAMON;
v4l2_event_queue(&uvc->vdev, &v4l2_event);
- return USB_GADGET_DELAYED_STATUS;
+
+ /*
+ * Normally we would return USB_GADGET_DELAYED_STATUS
+ * but status phase might try to continue in between
+ * this function returning and the delayed status
+ * actually being set
+ */
+ return 0;
default:
return -EINVAL;
diff --git a/drivers/usb/gadget/function/uvc_v4l2.c
b/drivers/usb/gadget/function/uvc_v4l2.c
index fdf02b6987c0..0592e13d861c 100644
--- a/drivers/usb/gadget/function/uvc_v4l2.c
+++ b/drivers/usb/gadget/function/uvc_v4l2.c
@@ -235,6 +235,8 @@ uvc_v4l2_streamoff(struct file *file, void *fh, enum
v4l2_buf_type type)
uvc->state = UVC_STATE_CONNECTED;
+ uvc_function_setup_continue(uvc);
+
return 0;
}
--
2.17.0
--
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