From patchwork Fri Aug 5 07:47:13 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guennadi Liakhovetski X-Patchwork-Id: 1037602 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.4) with ESMTP id p757lQOB026740 for ; Fri, 5 Aug 2011 07:47:26 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755940Ab1HEHrY (ORCPT ); Fri, 5 Aug 2011 03:47:24 -0400 Received: from moutng.kundenserver.de ([212.227.126.171]:59175 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755895Ab1HEHrW (ORCPT ); Fri, 5 Aug 2011 03:47:22 -0400 Received: from axis700.grange (dslb-178-006-240-175.pools.arcor-ip.net [178.6.240.175]) by mrelayeu.kundenserver.de (node=mrbap3) with ESMTP (Nemesis) id 0MA6Q5-1Qdwb5194L-00BOp0; Fri, 05 Aug 2011 09:47:14 +0200 Received: by axis700.grange (Postfix, from userid 1000) id E7F49189B6E; Fri, 5 Aug 2011 09:47:13 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by axis700.grange (Postfix) with ESMTP id E22E2189B6D; Fri, 5 Aug 2011 09:47:13 +0200 (CEST) Date: Fri, 5 Aug 2011 09:47:13 +0200 (CEST) From: Guennadi Liakhovetski X-X-Sender: lyakh@axis700.grange To: Linux Media Mailing List cc: Sakari Ailus , Hans Verkuil , Pawel Osciak , Sakari Ailus , Laurent Pinchart , Mauro Carvalho Chehab Subject: [PATCH 1/6 v4] V4L: add two new ioctl()s for multi-size videobuffer management In-Reply-To: Message-ID: References: MIME-Version: 1.0 X-Provags-ID: V02:K0:xTY3RdPTxzvGW2XM/G1NBEiFFBPQBtVCW0tqOwuBlt1 DVtlNliawkb46Uwi5SlUZk941EnRkDIT/6CUIhP7JJGWLgqsJE tTzpPkEexHOQ9w5AWY5bm+Ws4+Cau056fNSok3X8fQoyOit/RO KYeWsrDieyRB2sFTGfG/AFwnvZ8VBpOmN9lm670Bmx0Vr3W7lb zELqAPhzCxnzoisxHlsOZ7wrGXi9m8kZ8XJm1HT3UE= Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Fri, 05 Aug 2011 07:47:26 +0000 (UTC) A possibility to preallocate and initialise buffers of different sizes in V4L2 is required for an efficient implementation of asnapshot mode. This patch adds two new ioctl()s: VIDIOC_CREATE_BUFS and VIDIOC_PREPARE_BUF and defines respective data structures. Signed-off-by: Guennadi Liakhovetski --- v4: 1. CREATE_BUFS now takes an array of plane sizes and a fourcc code in its argument, instead of a frame format specification, including documentation update 2. documentation improvements, as suggested by Hans 3. increased reserved fields to 18, as suggested by Sakari Documentation/DocBook/media/v4l/io.xml | 17 ++ Documentation/DocBook/media/v4l/v4l2.xml | 2 + .../DocBook/media/v4l/vidioc-create-bufs.xml | 161 ++++++++++++++++++++ .../DocBook/media/v4l/vidioc-prepare-buf.xml | 96 ++++++++++++ drivers/media/video/v4l2-compat-ioctl32.c | 6 + drivers/media/video/v4l2-ioctl.c | 26 +++ include/linux/videodev2.h | 18 +++ include/media/v4l2-ioctl.h | 2 + 8 files changed, 328 insertions(+), 0 deletions(-) create mode 100644 Documentation/DocBook/media/v4l/vidioc-create-bufs.xml create mode 100644 Documentation/DocBook/media/v4l/vidioc-prepare-buf.xml diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml index 227e7ac..ff03dd2 100644 --- a/Documentation/DocBook/media/v4l/io.xml +++ b/Documentation/DocBook/media/v4l/io.xml @@ -927,6 +927,23 @@ ioctl is called. Applications set or clear this flag before calling the VIDIOC_QBUF ioctl. + + V4L2_BUF_FLAG_NO_CACHE_INVALIDATE + 0x0400 + Caches do not have to be invalidated for this buffer. +Typically applications shall use this flag if the data captured in the buffer +is not going to be touched by the CPU, instead the buffer will, probably, be +passed on to a DMA-capable hardware unit for further processing or output. + + + + V4L2_BUF_FLAG_NO_CACHE_CLEAN + 0x0800 + Caches do not have to be cleaned for this buffer. +Typically applications shall use this flag for output buffers if the data +in this buffer has not been created by the CPU but by some DMA-capable unit, +in which case caches have not been used. + diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml index 0d05e87..06bb179 100644 --- a/Documentation/DocBook/media/v4l/v4l2.xml +++ b/Documentation/DocBook/media/v4l/v4l2.xml @@ -462,6 +462,7 @@ and discussions on the V4L mailing list. &sub-close; &sub-ioctl; + &sub-create-bufs; &sub-cropcap; &sub-dbg-g-chip-ident; &sub-dbg-g-register; @@ -504,6 +505,7 @@ and discussions on the V4L mailing list. &sub-queryctrl; &sub-query-dv-preset; &sub-querystd; + &sub-prepare-buf; &sub-reqbufs; &sub-s-hw-freq-seek; &sub-streamon; diff --git a/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml b/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml new file mode 100644 index 0000000..b37b9a4 --- /dev/null +++ b/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml @@ -0,0 +1,161 @@ + + + ioctl VIDIOC_CREATE_BUFS + &manvol; + + + + VIDIOC_CREATE_BUFS + Create buffers for Memory Mapped or User Pointer I/O + + + + + + int ioctl + int fd + int request + struct v4l2_create_buffers *argp + + + + + + Arguments + + + + fd + + &fd; + + + + request + + VIDIOC_CREATE_BUFS + + + + argp + + + + + + + + + Description + + This ioctl is used to create buffers for memory +mapped or user pointer +I/O. It can be used as an alternative or in addition to the +VIDIOC_REQBUFS ioctl, when a tighter control over buffers +is required. This ioctl can be called multiple times to create buffers of +different sizes. + + To allocate device buffers applications initialize relevant +fields of the v4l2_create_buffers structure. +They set the type field to the respective stream +or buffer type. count must be set to the number of +required buffers. memory specifies the required I/O +method. If num_planes == 0 or all elements of the +sizes array are 0, then buffers, suitable for the +currently configured video format, are allocated, exactly like for the +VIDIOC_REQBUFS ioctl. If +num_planes > 0 and at least some of the respective +sizes elements are non-zero, this information will be +used for buffer-allocation. The reserved array must +be zeroed. When the ioctl is called with a pointer to this structure the driver +will attempt to allocate up to the requested number of buffers and store the +actual number allocated and the starting index in the +count and the index +fields respectively. On return count can be smaller +than the number requested. + When the I/O method is not supported the ioctl +returns an &EINVAL;. + + + struct <structname>v4l2_create_buffers</structname> + + &cs-str; + + + __u32 + index + The starting buffer index, returned by the driver. + + + __u32 + count + The number of buffers requested or granted. + + + __u32 + type + V4L2 buffer type: one of V4L2_BUF_TYPE_* +values. + + + __u32 + memory + Applications set this field to +V4L2_MEMORY_MMAP or +V4L2_MEMORY_USERPTR. + + + __u32 + fourcc + One of V4L2_PIX_FMT_* FOURCCs of the video data. + + + __u32 + num_planes + Number of planes or 0 to use the current format. + + + __u32 + size[VIDEO_MAX_PLANES] + Explicit sizes of buffers, being created. + + + __u32 + reserved[18] + A place holder for future extensions. + + + +
+ + + + &return-value; + + + + ENOMEM + + No memory to allocate buffers for memory +mapped I/O. + + + + EINVAL + + The buffer type (type field) or the +requested I/O method (memory) is not +supported. + + + + + + + diff --git a/Documentation/DocBook/media/v4l/vidioc-prepare-buf.xml b/Documentation/DocBook/media/v4l/vidioc-prepare-buf.xml new file mode 100644 index 0000000..509e752 --- /dev/null +++ b/Documentation/DocBook/media/v4l/vidioc-prepare-buf.xml @@ -0,0 +1,96 @@ + + + ioctl VIDIOC_PREPARE_BUF + &manvol; + + + + VIDIOC_PREPARE_BUF + Prepare a buffer for I/O + + + + + + int ioctl + int fd + int request + struct v4l2_buffer *argp + + + + + + Arguments + + + + fd + + &fd; + + + + request + + VIDIOC_PREPARE_BUF + + + + argp + + + + + + + + + Description + + Applications can optionally call the +VIDIOC_PREPARE_BUF ioctl to pass ownership of the buffer +to the driver before actually enqueuing it, using the +VIDIOC_QBUF ioctl, and to prepare it for future I/O. +Such preparations may include cache invalidation or cleaning. Performing them +in advance saves time during the actual I/O. In case such cache operations are +not required, the application can use one of +V4L2_BUF_FLAG_NO_CACHE_INVALIDATE and +V4L2_BUF_FLAG_NO_CACHE_CLEAN flags to skip the respective +step. + + The v4l2_buffer structure is +specified in . + + + + &return-value; + + + + EBUSY + + File I/O is in progress. + + + + EINVAL + + The buffer type is not +supported, or the index is out of bounds, +or no buffers have been allocated yet, or the +userptr or +length are invalid. + + + + + + + diff --git a/drivers/media/video/v4l2-compat-ioctl32.c b/drivers/media/video/v4l2-compat-ioctl32.c index 61979b7..ee5eec8 100644 --- a/drivers/media/video/v4l2-compat-ioctl32.c +++ b/drivers/media/video/v4l2-compat-ioctl32.c @@ -702,6 +702,7 @@ static int put_v4l2_event32(struct v4l2_event *kp, struct v4l2_event32 __user *u #define VIDIOC_S_EXT_CTRLS32 _IOWR('V', 72, struct v4l2_ext_controls32) #define VIDIOC_TRY_EXT_CTRLS32 _IOWR('V', 73, struct v4l2_ext_controls32) #define VIDIOC_DQEVENT32 _IOR ('V', 89, struct v4l2_event32) +#define VIDIOC_PREPARE_BUF32 _IOWR('V', 93, struct v4l2_buffer32) #define VIDIOC_OVERLAY32 _IOW ('V', 14, s32) #define VIDIOC_STREAMON32 _IOW ('V', 18, s32) @@ -751,6 +752,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar case VIDIOC_S_INPUT32: cmd = VIDIOC_S_INPUT; break; case VIDIOC_G_OUTPUT32: cmd = VIDIOC_G_OUTPUT; break; case VIDIOC_S_OUTPUT32: cmd = VIDIOC_S_OUTPUT; break; + case VIDIOC_PREPARE_BUF32: cmd = VIDIOC_PREPARE_BUF; break; } switch (cmd) { @@ -775,6 +777,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar compatible_arg = 0; break; + case VIDIOC_PREPARE_BUF: case VIDIOC_QUERYBUF: case VIDIOC_QBUF: case VIDIOC_DQBUF: @@ -860,6 +863,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar err = put_v4l2_format32(&karg.v2f, up); break; + case VIDIOC_PREPARE_BUF: case VIDIOC_QUERYBUF: case VIDIOC_QBUF: case VIDIOC_DQBUF: @@ -959,6 +963,8 @@ long v4l2_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg) case VIDIOC_DQEVENT32: case VIDIOC_SUBSCRIBE_EVENT: case VIDIOC_UNSUBSCRIBE_EVENT: + case VIDIOC_CREATE_BUFS: + case VIDIOC_PREPARE_BUF32: ret = do_video_ioctl(file, cmd, arg); break; diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c index 002ce13..3da87c0 100644 --- a/drivers/media/video/v4l2-ioctl.c +++ b/drivers/media/video/v4l2-ioctl.c @@ -260,6 +260,8 @@ static const char *v4l2_ioctls[] = { [_IOC_NR(VIDIOC_DQEVENT)] = "VIDIOC_DQEVENT", [_IOC_NR(VIDIOC_SUBSCRIBE_EVENT)] = "VIDIOC_SUBSCRIBE_EVENT", [_IOC_NR(VIDIOC_UNSUBSCRIBE_EVENT)] = "VIDIOC_UNSUBSCRIBE_EVENT", + [_IOC_NR(VIDIOC_CREATE_BUFS)] = "VIDIOC_CREATE_BUFS", + [_IOC_NR(VIDIOC_PREPARE_BUF)] = "VIDIOC_PREPARE_BUF", }; #define V4L2_IOCTLS ARRAY_SIZE(v4l2_ioctls) @@ -2216,6 +2218,30 @@ static long __video_do_ioctl(struct file *file, dbgarg(cmd, "type=0x%8.8x", sub->type); break; } + case VIDIOC_CREATE_BUFS: + { + struct v4l2_create_buffers *create = arg; + + if (!ops->vidioc_create_bufs) + break; + + ret = ops->vidioc_create_bufs(file, fh, create); + + dbgarg(cmd, "count=%u @ %u\n", create->count, create->index); + break; + } + case VIDIOC_PREPARE_BUF: + { + struct v4l2_buffer *b = arg; + + if (!ops->vidioc_prepare_buf) + break; + + ret = ops->vidioc_prepare_buf(file, fh, b); + + dbgarg(cmd, "index=%d", b->index); + break; + } default: { bool valid_prio = true; diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index fca24cc..3cd0cb3 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -653,6 +653,9 @@ struct v4l2_buffer { #define V4L2_BUF_FLAG_ERROR 0x0040 #define V4L2_BUF_FLAG_TIMECODE 0x0100 /* timecode field is valid */ #define V4L2_BUF_FLAG_INPUT 0x0200 /* input field is valid */ +/* Cache handling flags */ +#define V4L2_BUF_FLAG_NO_CACHE_INVALIDATE 0x0400 +#define V4L2_BUF_FLAG_NO_CACHE_CLEAN 0x0800 /* * O V E R L A Y P R E V I E W @@ -2092,6 +2095,18 @@ struct v4l2_dbg_chip_ident { __u32 revision; /* chip revision, chip specific */ } __attribute__ ((packed)); +/* VIDIOC_CREATE_BUFS */ +struct v4l2_create_buffers { + __u32 index; /* output: buffers index...index + count - 1 have been created */ + __u32 count; + __u32 type; + __u32 memory; + __u32 fourcc; + __u32 num_planes; + __u32 sizes[VIDEO_MAX_PLANES]; + __u32 reserved[18]; +}; + /* * I O C T L C O D E S F O R V I D E O D E V I C E S * @@ -2182,6 +2197,9 @@ struct v4l2_dbg_chip_ident { #define VIDIOC_SUBSCRIBE_EVENT _IOW('V', 90, struct v4l2_event_subscription) #define VIDIOC_UNSUBSCRIBE_EVENT _IOW('V', 91, struct v4l2_event_subscription) +#define VIDIOC_CREATE_BUFS _IOWR('V', 92, struct v4l2_create_buffers) +#define VIDIOC_PREPARE_BUF _IOW('V', 93, struct v4l2_buffer) + /* Reminder: when adding new ioctls please add support for them to drivers/media/video/v4l2-compat-ioctl32.c as well! */ diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h index dd9f1e7..4d1c74a 100644 --- a/include/media/v4l2-ioctl.h +++ b/include/media/v4l2-ioctl.h @@ -122,6 +122,8 @@ struct v4l2_ioctl_ops { int (*vidioc_qbuf) (struct file *file, void *fh, struct v4l2_buffer *b); int (*vidioc_dqbuf) (struct file *file, void *fh, struct v4l2_buffer *b); + int (*vidioc_create_bufs)(struct file *file, void *fh, struct v4l2_create_buffers *b); + int (*vidioc_prepare_buf)(struct file *file, void *fh, struct v4l2_buffer *b); int (*vidioc_overlay) (struct file *file, void *fh, unsigned int i); int (*vidioc_g_fbuf) (struct file *file, void *fh,