diff mbox series

usb: gadget: function: uvc: set req_size once when the vb2 queue is calculated

Message ID 20240404-uvc_request_calc_once-v1-1-fea7fd8f0496@pengutronix.de (mailing list archive)
State New, archived
Headers show
Series usb: gadget: function: uvc: set req_size once when the vb2 queue is calculated | expand

Commit Message

Michael Grzeschik April 4, 2024, 8:35 a.m. UTC 
The uvc gadget driver is calculating the req_size on every
video_enable/alloc_request and is based on the fixed configfs parameters
maxpacket, maxburst and mult.

As those parameters can not be changed once the gadget is started and
the same calculation is done already early on the
vb2_streamon/queue_setup path its save to remove one extra calculation
and reuse the calculation from uvc_queue_setup for the allocation step.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
---
 drivers/usb/gadget/function/uvc_queue.c |  2 ++
 drivers/usb/gadget/function/uvc_video.c | 15 ++-------------
 2 files changed, 4 insertions(+), 13 deletions(-)


---
base-commit: 5bab5dc780c9ed0c69fc2f828015532acf4a7848
change-id: 20240404-uvc_request_calc_once-a73df94665e6

Best regards,

Comments

Greg KH July 31, 2024, 8:30 a.m. UTC | #1 
On Thu, Apr 04, 2024 at 10:35:01AM +0200, Michael Grzeschik wrote:
> The uvc gadget driver is calculating the req_size on every
> video_enable/alloc_request and is based on the fixed configfs parameters
> maxpacket, maxburst and mult.
> 
> As those parameters can not be changed once the gadget is started and
> the same calculation is done already early on the
> vb2_streamon/queue_setup path its save to remove one extra calculation
> and reuse the calculation from uvc_queue_setup for the allocation step.
> 
> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
> ---
>  drivers/usb/gadget/function/uvc_queue.c |  2 ++
>  drivers/usb/gadget/function/uvc_video.c | 15 ++-------------
>  2 files changed, 4 insertions(+), 13 deletions(-)

Is this still needed?  If so, can you rebase and resubmit it?

thanks,

greg k-h
diff mbox series

Patch

diff --git a/drivers/usb/gadget/function/uvc_queue.c b/drivers/usb/gadget/function/uvc_queue.c
index 0aa3d7e1f3cc3..ce51643fc4639 100644
--- a/drivers/usb/gadget/function/uvc_queue.c
+++ b/drivers/usb/gadget/function/uvc_queue.c
@@ -63,6 +63,8 @@  static int uvc_queue_setup(struct vb2_queue *vq,
 	 */
 	nreq = DIV_ROUND_UP(DIV_ROUND_UP(sizes[0], 2), req_size);
 	nreq = clamp(nreq, 4U, 64U);
+
+	video->req_size = req_size;
 	video->uvc_num_requests = nreq;
 
 	return 0;
diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c
index d41f5f31dadd5..95bb64e16f3da 100644
--- a/drivers/usb/gadget/function/uvc_video.c
+++ b/drivers/usb/gadget/function/uvc_video.c
@@ -496,7 +496,6 @@  uvc_video_free_requests(struct uvc_video *video)
 	INIT_LIST_HEAD(&video->ureqs);
 	INIT_LIST_HEAD(&video->req_free);
 	INIT_LIST_HEAD(&video->req_ready);
-	video->req_size = 0;
 	return 0;
 }
 
@@ -504,16 +503,9 @@  static int
 uvc_video_alloc_requests(struct uvc_video *video)
 {
 	struct uvc_request *ureq;
-	unsigned int req_size;
 	unsigned int i;
 	int ret = -ENOMEM;
 
-	BUG_ON(video->req_size);
-
-	req_size = video->ep->maxpacket
-		 * max_t(unsigned int, video->ep->maxburst, 1)
-		 * (video->ep->mult);
-
 	for (i = 0; i < video->uvc_num_requests; i++) {
 		ureq = kzalloc(sizeof(struct uvc_request), GFP_KERNEL);
 		if (ureq == NULL)
@@ -523,7 +515,7 @@  uvc_video_alloc_requests(struct uvc_video *video)
 
 		list_add_tail(&ureq->list, &video->ureqs);
 
-		ureq->req_buffer = kmalloc(req_size, GFP_KERNEL);
+		ureq->req_buffer = kmalloc(video->req_size, GFP_KERNEL);
 		if (ureq->req_buffer == NULL)
 			goto error;
 
@@ -541,12 +533,10 @@  uvc_video_alloc_requests(struct uvc_video *video)
 		list_add_tail(&ureq->req->list, &video->req_free);
 		/* req_size/PAGE_SIZE + 1 for overruns and + 1 for header */
 		sg_alloc_table(&ureq->sgt,
-			       DIV_ROUND_UP(req_size - UVCG_REQUEST_HEADER_LEN,
+			       DIV_ROUND_UP(video->req_size - UVCG_REQUEST_HEADER_LEN,
 					    PAGE_SIZE) + 2, GFP_KERNEL);
 	}
 
-	video->req_size = req_size;
-
 	return 0;
 
 error:
@@ -699,7 +689,6 @@  uvcg_video_disable(struct uvc_video *video)
 	INIT_LIST_HEAD(&video->ureqs);
 	INIT_LIST_HEAD(&video->req_free);
 	INIT_LIST_HEAD(&video->req_ready);
-	video->req_size = 0;
 	spin_unlock_irqrestore(&video->req_lock, flags);
 
 	/*