From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ams-iport-1.cisco.com ([144.254.224.140]:38216 "EHLO ams-iport-1.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757506Ab2IMLxj (ORCPT ); Thu, 13 Sep 2012 07:53:39 -0400 From: Hans Verkuil To: Prabhakar Lad Subject: Re: [PATCH v3] media: v4l2-ctrl: add a helper function to modify the menu Date: Thu, 13 Sep 2012 13:53:34 +0200 Cc: Laurent Pinchart , LMML , dlos , linux-kernel@vger.kernel.org, Manjunath Hadli , linux-doc@vger.kernel.org, Hans Verkuil , "Sakari Ailus" , Sylwester Nawrocki , Mauro Carvalho Chehab , Hans de Goede , Kyungmin Park , "Guennadi Liakhovetski" , Rob Landley References: <1347373418-18927-1-git-send-email-prabhakar.lad@ti.com> <1481481.zLUeB0rsrG@avalon> <5051C6E8.8030109@ti.com> In-Reply-To: <5051C6E8.8030109@ti.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201209131353.34497.hansverk@cisco.com> Sender: linux-media-owner@vger.kernel.org List-ID: On Thu 13 September 2012 13:43:36 Prabhakar Lad wrote: > Hi Laurent, > > Thanks for the review. > > On Thursday 13 September 2012 06:45 AM, Laurent Pinchart wrote: > > Hi Prabhakar, > > > > Thanks for the patch. > > > > On Tuesday 11 September 2012 19:53:38 Prabhakar Lad wrote: > >> From: Lad, Prabhakar > >> > >> Add a helper function to modify the menu, max and default value > >> to set. > >> > >> Signed-off-by: Lad, Prabhakar > >> Signed-off-by: Manjunath Hadli > >> Cc: Hans Verkuil > >> Cc: Sakari Ailus > >> Cc: Sylwester Nawrocki > >> Cc: Laurent Pinchart > >> Cc: Mauro Carvalho Chehab > >> Cc: Hans de Goede > >> Cc: Kyungmin Park > >> Cc: Guennadi Liakhovetski > >> Cc: Rob Landley > >> --- > >> Changes for v3: > >> 1: Fixed style/grammer issues as pointed by Hans. > >> Thanks Hans for providing the description. > >> > >> Changes for v2: > >> 1: Fixed review comments from Hans, to have return type as > >> void, add WARN_ON() for fail conditions, allow this fucntion > >> to modify the menu of custom controls. > >> > >> Documentation/video4linux/v4l2-controls.txt | 29 ++++++++++++++++++++++++ > >> drivers/media/v4l2-core/v4l2-ctrls.c | 17 +++++++++++++++ > >> include/media/v4l2-ctrls.h | 11 ++++++++++ > >> 3 files changed, 57 insertions(+), 0 deletions(-) > >> > >> diff --git a/Documentation/video4linux/v4l2-controls.txt > >> b/Documentation/video4linux/v4l2-controls.txt index 43da22b..01d0a82 100644 > >> --- a/Documentation/video4linux/v4l2-controls.txt > >> +++ b/Documentation/video4linux/v4l2-controls.txt > >> @@ -367,6 +367,35 @@ it to 0 means that all menu items are supported. > >> You set this mask either through the v4l2_ctrl_config struct for a custom > >> control, or by calling v4l2_ctrl_new_std_menu(). > >> > >> +There are situations where menu items may be device specific. In such cases > >> the > >> +framework provides a helper function to change the menu: > >> + > >> +void v4l2_ctrl_modify_menu(struct v4l2_ctrl *ctrl, const char * const > >> *qmenu, > >> + s32 max, u32 menu_skip_mask, s32 def); > > > > Sorry if this is a stupid question, but wouldn't it be better to add a > > function to create a custom menu instead of modifying it afterwards ? > > > Create a custom menu? eventually everything boils down to modifying the > menu itself. Laurent, the reason we went for modifying a standard control is that that ensures that the control name and type is all standardized. The only thing that can be changed later is the menu contents. Regards, Hans > > Regards, > --Prabhakar Lad > > >> + > >> +A good example is the test pattern control for capture/display/sensors > >> devices > >> +that have the capability to generate test patterns. These test patterns are > >> +hardware specific, so the contents of the menu will vary from device to > >> device. > >> + > >> +This helper function is used to modify the menu, max, mask and the default > >> +value of the control. > >> + > >> +Example: > >> + > >> + static const char * const test_pattern[] = { > >> + "Disabled", > >> + "Vertical Bars", > >> + "Solid Black", > >> + "Solid White", > >> + NULL, > >> + }; > >> + struct v4l2_ctrl *test_pattern_ctrl = > >> + v4l2_ctrl_new_std_menu(&foo->ctrl_handler, &foo_ctrl_ops, > >> + V4L2_CID_TEST_PATTERN, V4L2_TEST_PATTERN_DISABLED, 0, > >> + V4L2_TEST_PATTERN_DISABLED); > >> + > >> + v4l2_ctrl_modify_menu(test_pattern_ctrl, test_pattern, 3, 0, > >> + V4L2_TEST_PATTERN_DISABLED); > >> > >> Custom Controls > >> =============== > > > >