From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964815AbbCLPsZ (ORCPT ); Thu, 12 Mar 2015 11:48:25 -0400 Received: from mailout3.samsung.com ([203.254.224.33]:53375 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030313AbbCLPqm (ORCPT ); Thu, 12 Mar 2015 11:46:42 -0400 X-AuditID: cbfee61b-f79d76d0000024d6-7a-5501b4e0969a From: Jacek Anaszewski To: linux-leds@vger.kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Cc: kyungmin.park@samsung.com, pavel@ucw.cz, cooloney@gmail.com, rpurdie@rpsys.net, sakari.ailus@iki.fi, s.nawrocki@samsung.com, Jacek Anaszewski Subject: [PATCH/RFC v13 10/13] Documentation: leds: Add description of v4l2-flash sub-device Date: Thu, 12 Mar 2015 16:45:11 +0100 Message-id: <1426175114-14876-11-git-send-email-j.anaszewski@samsung.com> X-Mailer: git-send-email 1.7.9.5 In-reply-to: <1426175114-14876-1-git-send-email-j.anaszewski@samsung.com> References: <1426175114-14876-1-git-send-email-j.anaszewski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrDLMWRmVeSWpSXmKPExsVy+t9jQd0HWxhDDa79ULQ4unMik8X8I+dY LXqvPme0ONv0ht3i8q45bBZb36xjtOjZsJXV4u6po2wWu3c9ZbU4/Kad1eLM/pVsDtweO2fd Zfc4/HUhi8ee+T9YPfq2rGL0WLH6O7vH501yAWxRXDYpqTmZZalF+nYJXBmPF89nLNjPU9G7 6DxzA+N5ri5GTg4JAROJQycaWCBsMYkL99azdTFycQgJTGeU+Lt4GTOE084kcezkM7AqNgFD iZ8vXjOB2CIC5RJ77jxmByliFtjAKHF5QiNYkbBAnMTlhq+MIDaLgKrEgdctQA0cHLwCnhJv e1RATAkBBYk5k2xAKjiBot33P4BVCwl4SEze8Jd9AiPvAkaGVYyiqQXJBcVJ6blGesWJucWl eel6yfm5mxjBYfhMegfjqgaLQ4wCHIxKPLwXvjOECrEmlhVX5h5ilOBgVhLhNZ3PGCrEm5JY WZValB9fVJqTWnyIUZqDRUmcV8m+LURIID2xJDU7NbUgtQgmy8TBKdXAOO1LM6vKgaBCt5k+ d79UlHx/8rtjW1B57bePM5+mudVureBIl5r6gWdl/r0v0rvefNp3+Z2S785HHoyZXoXXbDLX HnVWbzvPk7j037uCW/xm2oeDZiy/d8yr/v+xiL8TdnVMkehl4DH/sPj51npTea23C2MLJBdl nbMpsP66sy7jwvvOFAWNuUosxRmJhlrMRcWJAFj9iqI/AgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch extends LED Flash class documention by the description of interactions with v4l2-flash sub-device. Signed-off-by: Jacek Anaszewski Acked-by: Kyungmin Park Acked-by: Sakari Ailus Cc: Bryan Wu Cc: Richard Purdie --- Documentation/leds/leds-class-flash.txt | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/Documentation/leds/leds-class-flash.txt b/Documentation/leds/leds-class-flash.txt index 19bb673..8623413 100644 --- a/Documentation/leds/leds-class-flash.txt +++ b/Documentation/leds/leds-class-flash.txt @@ -20,3 +20,16 @@ Following sysfs attributes are exposed for controlling flash LED devices: - max_flash_timeout - flash_strobe - flash_fault + +A LED subsystem driver can be controlled also from the level of VideoForLinux2 +subsystem. In order to enable this CONFIG_V4L2_FLASH_LED_CLASS symbol has to +be defined in the kernel config. The driver must call the v4l2_flash_init +function to get registered in the V4L2 subsystem. On remove the +v4l2_flash_release function has to be called (see ). + +After proper initialization a V4L2 Flash sub-device is created. The sub-device +exposes a number of V4L2 controls, which allow for controlling a LED Flash class +device with use of its internal kernel API. +Opening the V4L2 Flash sub-device makes the LED subsystem sysfs interface +unavailable. The interface is re-enabled after the V4L2 Flash sub-device +is closed. -- 1.7.9.5