From 6016af82eafcb6e086a8f2a2197b46029a843d68 Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Thu, 10 May 2012 02:02:07 -0300 Subject: [media] v4l2: use __u32 rather than enums in ioctl() structs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit V4L2 uses the enum type in IOCTL arguments in IOCTLs that were defined until the use of enum was considered less than ideal. Recently Rémi Denis-Courmont brought up the issue by proposing a patch to convert the enums to unsigned: This sparked a long discussion where another solution to the issue was proposed: two sets of IOCTL structures, one with __u32 and the other with enums, and conversion code between the two: Both approaches implement a complete solution that resolves the problem. The first one is simple but requires assuming enums and __u32 are the same in size (so we won't break the ABI) while the second one is more complex and less clean but does not require making that assumption. The issue boils down to whether enums are fundamentally different from __u32 or not, and can the former be substituted by the latter. During the discussion it was concluded that the __u32 has the same size as enums on all archs Linux is supported: it has not been shown that replacing those enums in IOCTL arguments would break neither source or binary compatibility. If no such reason is found, just replacing the enums with __u32s is the way to go. This is what this patch does. This patch is slightly different from Remi's first RFC (link above): it uses __u32 instead of unsigned and also changes the arguments of VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY. Signed-off-by: Rémi Denis-Courmont Signed-off-by: Sakari Ailus Acked-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/DocBook/media/v4l/io.xml | 12 +++++++----- Documentation/DocBook/media/v4l/vidioc-create-bufs.xml | 10 ++++++---- Documentation/DocBook/media/v4l/vidioc-cropcap.xml | 4 ++-- Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml | 4 ++-- Documentation/DocBook/media/v4l/vidioc-g-crop.xml | 4 ++-- Documentation/DocBook/media/v4l/vidioc-g-fmt.xml | 2 +- Documentation/DocBook/media/v4l/vidioc-g-frequency.xml | 6 +++--- Documentation/DocBook/media/v4l/vidioc-g-parm.xml | 5 +++-- Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml | 2 +- Documentation/DocBook/media/v4l/vidioc-g-tuner.xml | 2 +- Documentation/DocBook/media/v4l/vidioc-queryctrl.xml | 2 +- Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 7 ++++--- Documentation/DocBook/media/v4l/vidioc-s-hw-freq-seek.xml | 5 +++-- 13 files changed, 36 insertions(+), 29 deletions(-) (limited to 'Documentation/DocBook') diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml index b815929b5bba..fd6aca2922b6 100644 --- a/Documentation/DocBook/media/v4l/io.xml +++ b/Documentation/DocBook/media/v4l/io.xml @@ -543,12 +543,13 @@ and can range from zero to the number of buffers allocated with the &VIDIOC-REQBUFS; ioctl (&v4l2-requestbuffers; count) minus one. - &v4l2-buf-type; + __u32 type Type of the buffer, same as &v4l2-format; type or &v4l2-requestbuffers; -type, set by the application. +type, set by the application. See __u32 @@ -568,7 +569,7 @@ refers to an input stream, applications when an output stream. linkend="buffer-flags" />. - &v4l2-field; + __u32 field Indicates the field order of the image in the @@ -630,11 +631,12 @@ bandwidth. These devices identify by not enumerating any video standards, see . - &v4l2-memory; + __u32 memory This field must be set by applications and/or drivers -in accordance with the selected I/O method. +in accordance with the selected I/O method. See union diff --git a/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml b/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml index 73ae8a6cd004..184cdfc13081 100644 --- a/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml +++ b/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml @@ -94,16 +94,18 @@ information. The number of buffers requested or granted. - &v4l2-memory; + __u32 memory Applications set this field to V4L2_MEMORY_MMAP or -V4L2_MEMORY_USERPTR. +V4L2_MEMORY_USERPTR. See - &v4l2-format; + __u32 format - Filled in by the application, preserved by the driver. + Filled in by the application, preserved by the driver. + See . __u32 diff --git a/Documentation/DocBook/media/v4l/vidioc-cropcap.xml b/Documentation/DocBook/media/v4l/vidioc-cropcap.xml index b4f2f255211e..f1bac2c6e978 100644 --- a/Documentation/DocBook/media/v4l/vidioc-cropcap.xml +++ b/Documentation/DocBook/media/v4l/vidioc-cropcap.xml @@ -65,7 +65,7 @@ output. &cs-str; - &v4l2-buf-type; + __u32 type Type of the data stream, set by the application. Only these types are valid here: @@ -73,7 +73,7 @@ Only these types are valid here: V4L2_BUF_TYPE_VIDEO_OUTPUT, V4L2_BUF_TYPE_VIDEO_OVERLAY, and custom (driver defined) types with code V4L2_BUF_TYPE_PRIVATE -and higher. +and higher. See . struct v4l2_rect diff --git a/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml b/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml index 347d142e7431..81ebe48317fe 100644 --- a/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml +++ b/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml @@ -71,7 +71,7 @@ the application. This is in no way related to the pixelformat field. - &v4l2-buf-type; + __u32 type Type of the data stream, set by the application. Only these types are valid here: @@ -81,7 +81,7 @@ Only these types are valid here: V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE, V4L2_BUF_TYPE_VIDEO_OVERLAY, and custom (driver defined) types with code V4L2_BUF_TYPE_PRIVATE -and higher. +and higher. See . __u32 diff --git a/Documentation/DocBook/media/v4l/vidioc-g-crop.xml b/Documentation/DocBook/media/v4l/vidioc-g-crop.xml index 01a50640dce0..c4ff3b1887fb 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-crop.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-crop.xml @@ -100,14 +100,14 @@ changed and VIDIOC_S_CROP returns the &cs-str; - &v4l2-buf-type; + __u32 type Type of the data stream, set by the application. Only these types are valid here: V4L2_BUF_TYPE_VIDEO_CAPTURE, V4L2_BUF_TYPE_VIDEO_OUTPUT, V4L2_BUF_TYPE_VIDEO_OVERLAY, and custom (driver defined) types with code V4L2_BUF_TYPE_PRIVATE -and higher. +and higher. See . &v4l2-rect; diff --git a/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml b/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml index 17fbda15137b..52acff193a6f 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml @@ -116,7 +116,7 @@ this ioctl. - &v4l2-buf-type; + __u32 type Type of the data stream, see modulator field and the &v4l2-modulator; index field. - &v4l2-tuner-type; + __u32 type The tuner type. This is the same value as in the -&v4l2-tuner; type field. The type must be set +&v4l2-tuner; type field. See The type must be set to V4L2_TUNER_RADIO for /dev/radioX device nodes, and to V4L2_TUNER_ANALOG_TV for all others. The field is not applicable to modulators, &ie; ignored -by drivers. +by drivers. See __u32 diff --git a/Documentation/DocBook/media/v4l/vidioc-g-parm.xml b/Documentation/DocBook/media/v4l/vidioc-g-parm.xml index 19b1d85dd668..f83d2cdd1185 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-parm.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-parm.xml @@ -75,11 +75,12 @@ devices. &cs-ustr; - &v4l2-buf-type; + __u32 type The buffer (stream) type, same as &v4l2-format; -type, set by the application. +type, set by the application. See union diff --git a/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml b/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml index 71741daaf725..bd015d1563ff 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml @@ -148,7 +148,7 @@ using the &VIDIOC-S-FMT; ioctl as described in service_lines[1][0] to zero. - &v4l2-buf-type; + __u32 type Type of the data stream, see . Should be diff --git a/Documentation/DocBook/media/v4l/vidioc-g-tuner.xml b/Documentation/DocBook/media/v4l/vidioc-g-tuner.xml index 91ec2fb658f8..62a1aa200a36 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-tuner.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-tuner.xml @@ -107,7 +107,7 @@ user. - &v4l2-tuner-type; + __u32 type Type of the tuner, see . diff --git a/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml b/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml index 505f0206e5bd..e6645b996558 100644 --- a/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml +++ b/Documentation/DocBook/media/v4l/vidioc-queryctrl.xml @@ -127,7 +127,7 @@ the first control with a higher ID. Drivers which do not support this flag yet always return an &EINVAL;. - &v4l2-ctrl-type; + __u32 type Type of control, see . diff --git a/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml b/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml index 7be4b1d29b90..d7c95057bc51 100644 --- a/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml +++ b/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml @@ -92,18 +92,19 @@ streamoff.--> The number of buffers requested or granted. - &v4l2-buf-type; + __u32 type Type of the stream or buffers, this is the same as the &v4l2-format; type field. See for valid values. - &v4l2-memory; + __u32 memory Applications set this field to V4L2_MEMORY_MMAP or -V4L2_MEMORY_USERPTR. +V4L2_MEMORY_USERPTR. See . __u32 diff --git a/Documentation/DocBook/media/v4l/vidioc-s-hw-freq-seek.xml b/Documentation/DocBook/media/v4l/vidioc-s-hw-freq-seek.xml index 18b1a8266f7c..407dfceb71f0 100644 --- a/Documentation/DocBook/media/v4l/vidioc-s-hw-freq-seek.xml +++ b/Documentation/DocBook/media/v4l/vidioc-s-hw-freq-seek.xml @@ -73,10 +73,11 @@ same value as in the &v4l2-input; tuner field and the &v4l2-tuner; index field. - &v4l2-tuner-type; + __u32 type The tuner type. This is the same value as in the -&v4l2-tuner; type field. +&v4l2-tuner; type field. See __u32 -- cgit v1.2.3