From e81e7f9a0eb9536d5976acf5d95290338032a198 Mon Sep 17 00:00:00 2001 From: Michael Grzeschik Date: Mon, 28 Jun 2021 17:53:10 +0200 Subject: usb: gadget: uvc: add scatter gather support This patch adds support for scatter gather transfers. If the underlying gadgets sg_supported == true, then the videeobuf2-dma-sg is used and the encode routine maps all scatter entries to separate scatterlists for the usb gadget. When streaming 1080p with request size of 1024 times 3 bytes top shows a difference of about 6.4% CPU load applying this patch: PID USER PR NI VIRT RES %CPU %MEM TIME+ S COMMAND 64 root 0 -20 0.0m 0.0m 7.7 0.0 0:01.25 I [kworker/u5:0-uvcvideo] 83 root 0 -20 0.0m 0.0m 4.5 0.0 0:03.71 I [kworker/u5:3-uvcvideo] 307 root -51 0 0.0m 0.0m 3.8 0.0 0:01.05 S [irq/51-dwc3] vs. 64 root 0 -20 0.0m 0.0m 5.8 0.0 0:01.79 I [kworker/u5:0-uvcvideo] 306 root -51 0 0.0m 0.0m 3.2 0.0 0:01.97 S [irq/51-dwc3] 82 root 0 -20 0.0m 0.0m 0.6 0.0 0:01.86 I [kworker/u5:1-uvcvideo] Signed-off-by: Michael Grzeschik Link: https://lore.kernel.org/r/20210628155311.16762-5-m.grzeschik@pengutronix.de Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/uvc_queue.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers/usb/gadget/function/uvc_queue.h') diff --git a/drivers/usb/gadget/function/uvc_queue.h b/drivers/usb/gadget/function/uvc_queue.h index 2f0fff769843..05360a0767f6 100644 --- a/drivers/usb/gadget/function/uvc_queue.h +++ b/drivers/usb/gadget/function/uvc_queue.h @@ -34,6 +34,9 @@ struct uvc_buffer { enum uvc_buffer_state state; void *mem; + struct sg_table *sgt; + struct scatterlist *sg; + unsigned int offset; unsigned int length; unsigned int bytesused; }; @@ -50,6 +53,8 @@ struct uvc_video_queue { unsigned int buf_used; + bool use_sg; + spinlock_t irqlock; /* Protects flags and irqqueue */ struct list_head irqqueue; }; @@ -59,7 +64,7 @@ static inline int uvc_queue_streaming(struct uvc_video_queue *queue) return vb2_is_streaming(&queue->queue); } -int uvcg_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type, +int uvcg_queue_init(struct uvc_video_queue *queue, struct device *dev, enum v4l2_buf_type type, struct mutex *lock); void uvcg_free_buffers(struct uvc_video_queue *queue); -- cgit v1.2.3