From ece41454c6a5ed8f301ef1c37710ab222e577823 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Fri, 9 Nov 2018 09:26:10 -0500 Subject: [PATCH] media: uvcvideo: Abstract streaming object lifetime The streaming object is a key part of handling the UVC device. Although not critical, we are currently missing a call to destroy the mutex on clean up paths, and we are due to extend the objects complexity in the near future. Facilitate easy management of a stream object by creating a pair of functions to handle creating and destroying the allocation. The new uvc_stream_delete() function also performs the missing mutex_destroy() operation. Previously a failed streaming object allocation would cause uvc_parse_streaming() to return -EINVAL, which is inappropriate. If the constructor failes, we will instead return -ENOMEM. While we're here, fix the trivial spelling error in the function banner of uvc_delete(). Signed-off-by: Kieran Bingham Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/usb/uvc/uvc_driver.c | 54 +++++++++++++++++++++++++++----------- 1 file changed, 38 insertions(+), 16 deletions(-) diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index 67bd58c6f397..afb44d1c9d04 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -396,6 +396,39 @@ static struct uvc_streaming *uvc_stream_by_id(struct uvc_device *dev, int id) } /* ------------------------------------------------------------------------ + * Streaming Object Management + */ + +static void uvc_stream_delete(struct uvc_streaming *stream) +{ + mutex_destroy(&stream->mutex); + + usb_put_intf(stream->intf); + + kfree(stream->format); + kfree(stream->header.bmaControls); + kfree(stream); +} + +static struct uvc_streaming *uvc_stream_new(struct uvc_device *dev, + struct usb_interface *intf) +{ + struct uvc_streaming *stream; + + stream = kzalloc(sizeof(*stream), GFP_KERNEL); + if (stream == NULL) + return NULL; + + mutex_init(&stream->mutex); + + stream->dev = dev; + stream->intf = usb_get_intf(intf); + stream->intfnum = intf->cur_altsetting->desc.bInterfaceNumber; + + return stream; +} + +/* ------------------------------------------------------------------------ * Descriptors parsing */ @@ -687,17 +720,12 @@ static int uvc_parse_streaming(struct uvc_device *dev, return -EINVAL; } - streaming = kzalloc(sizeof(*streaming), GFP_KERNEL); + streaming = uvc_stream_new(dev, intf); if (streaming == NULL) { usb_driver_release_interface(&uvc_driver.driver, intf); - return -EINVAL; + return -ENOMEM; } - mutex_init(&streaming->mutex); - streaming->dev = dev; - streaming->intf = usb_get_intf(intf); - streaming->intfnum = intf->cur_altsetting->desc.bInterfaceNumber; - /* The Pico iMage webcam has its class-specific interface descriptors * after the endpoint descriptors. */ @@ -904,10 +932,7 @@ static int uvc_parse_streaming(struct uvc_device *dev, error: usb_driver_release_interface(&uvc_driver.driver, intf); - usb_put_intf(intf); - kfree(streaming->format); - kfree(streaming->header.bmaControls); - kfree(streaming); + uvc_stream_delete(streaming); return ret; } @@ -1815,7 +1840,7 @@ static int uvc_scan_device(struct uvc_device *dev) * is released. * * As this function is called after or during disconnect(), all URBs have - * already been canceled by the USB core. There is no need to kill the + * already been cancelled by the USB core. There is no need to kill the * interrupt URB manually. */ static void uvc_delete(struct kref *kref) @@ -1853,10 +1878,7 @@ static void uvc_delete(struct kref *kref) streaming = list_entry(p, struct uvc_streaming, list); usb_driver_release_interface(&uvc_driver.driver, streaming->intf); - usb_put_intf(streaming->intf); - kfree(streaming->format); - kfree(streaming->header.bmaControls); - kfree(streaming); + uvc_stream_delete(streaming); } kfree(dev); -- 2.11.0