From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:35802 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726963AbeHJNPs (ORCPT ); Fri, 10 Aug 2018 09:15:48 -0400 Date: Fri, 10 Aug 2018 12:46:23 +0200 From: Pavel Machek To: Hans Verkuil Cc: linux-media@vger.kernel.org, Alexandre Courbot , Hans Verkuil Subject: Re: [PATCHv16 01/34] Documentation: v4l: document request API Message-ID: <20180810104623.GA6350@amd> References: <20180705160337.54379-1-hverkuil@xs4all.nl> <20180705160337.54379-2-hverkuil@xs4all.nl> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="6c2NcOVqGQ03X4Wi" Content-Disposition: inline In-Reply-To: <20180705160337.54379-2-hverkuil@xs4all.nl> Sender: linux-media-owner@vger.kernel.org List-ID: --6c2NcOVqGQ03X4Wi Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > From: Alexandre Courbot >=20 > Document the request API for V4L2 devices, and amend the documentation > of system calls influenced by it. >=20 > Signed-off-by: Alexandre Courbot > Signed-off-by: Hans Verkuil > --- a/Documentation/media/uapi/v4l/buffer.rst > +++ b/Documentation/media/uapi/v4l/buffer.rst > @@ -306,10 +306,15 @@ struct v4l2_buffer > - A place holder for future extensions. Drivers and applications > must set this to 0. > * - __u32 > - - ``reserved`` > + - ``request_fd`` > - > - - A place holder for future extensions. Drivers and applications > - must set this to 0. > + - The file descriptor of the request to queue the buffer to. If sp= ecified > + and flag ``V4L2_BUF_FLAG_REQUEST_FD`` is set, then the buffer wi= ll be Delete "specified and" -- 0 is valid fd? > + queued to that request. This is set by the user when calling > + :ref:`ioctl VIDIOC_QBUF ` and ignored by other ioctls. > + If the device does not support requests, then ``EPERM`` will be returne= d. > + If requests are supported but an invalid request FD is given, then > + ``ENOENT`` will be returned. Should this still specify that this should be 0 if V4L2_BUF_FLAG_REQUEST_FD is not set? Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --6c2NcOVqGQ03X4Wi Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlttbP8ACgkQMOfwapXb+vJnkQCgpWbIB8uOuRXVG59azzJPejmd cFUAn0Qq5GmZIibPVvQ1fG4OLBucm8TS =4O5L -----END PGP SIGNATURE----- --6c2NcOVqGQ03X4Wi--