From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from osg.samsung.com ([64.30.133.232]:55399 "EHLO osg.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755819AbdJJIaM (ORCPT ); Tue, 10 Oct 2017 04:30:12 -0400 Date: Tue, 10 Oct 2017 05:30:04 -0300 From: Mauro Carvalho Chehab To: Sakari Ailus Cc: Linux Media Mailing List , Jonathan Corbet , Mauro Carvalho Chehab , Linux Doc Mailing List , Ricardo Ribalda Delgado , Hans Verkuil Subject: Re: [PATCH v7 1/7] media: add glossary.rst with a glossary of terms used at V4L2 spec Message-ID: <20171010053004.2d97795a@vento.lan> In-Reply-To: <20171006102229.evjyn77udfcc76gs@valkosipuli.retiisi.org.uk> References: <047245414a82a6553361b1dd3497f796855a657d.1506550930.git.mchehab@s-opensource.com> <20171006102229.evjyn77udfcc76gs@valkosipuli.retiisi.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Fri, 6 Oct 2017 13:22:29 +0300 Sakari Ailus escreveu: > > + Bridge driver > > + The same as V4L2 main driver. > > Not all V4L2 main drivers can be bridge drivers. Mem-to-mem devices, for > instance. How about: > > A driver for a device receiving image data from another device (or > transmitting it to a sub-device) controlled by a sub-device driver. Bridge > drivers typically act as V4L2 main drivers. That is not true for some device drivers we have. The GSPCA drivers are bridge drivers, but they don't use any sub-device (well, it should, but nobody will redesign it, as the efforts would be huge, for a very little gain). Also uvcdriver doesn't need sub-device drivers, as the camera's internal firmware does the interface with the sensors. We could, instead define it as: Bridge driver A driver that provides a bridge between the CPU's bus to the data and control buses of a media hardware. Often, the bridge driver is the same as V4L2 main driver. Thanks, Mauro