From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mailout4.w1.samsung.com ([210.118.77.14]:40417 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753255Ab1ISIsR (ORCPT ); Mon, 19 Sep 2011 04:48:17 -0400 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; charset=UTF-8 Received: from euspt2 ([210.118.77.14]) by mailout4.w1.samsung.com (Sun Java(tm) System Messaging Server 6.3-8.04 (built Jul 29 2009; 32bit)) with ESMTP id <0LRR008Z1HSF7D00@mailout4.w1.samsung.com> for linux-media@vger.kernel.org; Mon, 19 Sep 2011 09:48:15 +0100 (BST) Received: from linux.samsung.com ([106.116.38.10]) by spt2.w1.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTPA id <0LRR00MTKHSE7E@spt2.w1.samsung.com> for linux-media@vger.kernel.org; Mon, 19 Sep 2011 09:48:15 +0100 (BST) Date: Mon, 19 Sep 2011 10:48:14 +0200 From: Sylwester Nawrocki Subject: Re: [PATCH/RFC 1/2] v4l2: Add the parallel bus HREF signal polarity flags In-reply-to: <201109190105.29383.laurent.pinchart@ideasonboard.com> To: Laurent Pinchart Cc: Sylwester Nawrocki , Guennadi Liakhovetski , linux-media@vger.kernel.org, m.szyprowski@samsung.com, kyungmin.park@samsung.com, sw0312.kim@samsung.com, riverful.kim@samsung.com Message-id: <4E7701CE.6050201@samsung.com> References: <1316194123-21185-1-git-send-email-s.nawrocki@samsung.com> <4E74C57C.8030801@gmail.com> <201109190105.29383.laurent.pinchart@ideasonboard.com> Sender: linux-media-owner@vger.kernel.org List-ID: Hi Laurent, On 09/19/2011 01:05 AM, Laurent Pinchart wrote: > On Saturday 17 September 2011 18:06:20 Sylwester Nawrocki wrote: >> On 09/17/2011 02:34 PM, Guennadi Liakhovetski wrote: >>> On Sat, 17 Sep 2011, Sylwester Nawrocki wrote: >>>> On 09/17/2011 12:54 PM, Laurent Pinchart wrote: >>>>> On Friday 16 September 2011 19:28:42 Sylwester Nawrocki wrote: >>>>>> HREF is a signal indicating valid data during single line >>>>>> transmission. Add corresponding flags for this signal to the set of >>>>>> mediabus signal polarity flags. >>>>> >>>>> So that's a data valid signal that gates the pixel data ? The OMAP3 ISP >>>>> has a >>>> >>>> Yes, it's "horizontal window reference" signal, it's well described in >>>> this datasheet: http://www.morninghan.com/pdf/OV2640FSL_DS_(1_3).pdf >>>> >>>> AFAICS there can be also its vertical counterpart - VREF. >>>> >>>> Many devices seem to use this terminology. However, I realize, not all, >>>> as you're pointing out. So perhaps it's time for some naming contest >>>> now.. :-) >>> >>> No objections in principle, just one question though: can these signals >>> actually be used simultaneously with respective *SYNC signals or only as >>> an alternative? If the latter, maybe we could reuse same names by just >>> making them more generic? >> >> That's actually a good question. In my use cases only HREF is used as >> horizontal synchronization signal, i.e. physical bus interface has this >> signals: >> >> ->| PCLK >> ->| VSYNC >> ->| HREF >> ->| DATA[0:7] >> ->| FIELD >> >> For interlaced mode FIELD can be connected to the horizontal >> synchronization signal. For this case there is InvPolHSYNC bit in the host >> interface registers to indicate the polarity. There are 5 bits actually: >> >> InvPolPCLK >> InvPolVSYNC (vertical sychronization) >> InvPolHREF (horizontal synchronization) >> InvPolHSYNC (for interlaced mode only, FIELD port = horizontal sync. >> signal) InvPolFIELD (interlaced mode, FIELD port = FIELD signal) > > Shouldn't this be handled through platform data only ? Indeed, this is how it's done now and I didn't intend to change that. I just wanted to replace driver's private signal polarity flag definitions with the standard ones. Do you think I should rather keep these things in driver's public header? It's of course a way of less resistance :) To make things complete I thought about adding the FIELD flags, i.e. >>From 9bd11f9b14dffe877f9c546e068b4b4027c9472a Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Sun, 18 Sep 2011 11:28:58 +0200 Subject: [PATCH 1/2] v4l2: Add the parallel bus HREF and FIELD signal polarity flags HREF is a signal gating valid data during single line transmission. FIELD is an Even/Odd field selection signal, as specified in ITU-R BT.601 standard. Add corresponding flags for these signals to the set of media bus signal polarity flags. Signed-off-by: Sylwester Nawrocki Signed-off-by: Kyungmin Park --- include/media/v4l2-mediabus.h | 20 +++++++++++++------- 1 files changed, 13 insertions(+), 7 deletions(-) diff --git a/include/media/v4l2-mediabus.h b/include/media/v4l2-mediabus.h index 6114007..1952d9f 100644 --- a/include/media/v4l2-mediabus.h +++ b/include/media/v4l2-mediabus.h @@ -23,15 +23,21 @@ #define V4L2_MBUS_MASTER (1 << 0) #define V4L2_MBUS_SLAVE (1 << 1) /* Which signal polarities it supports */ -/* Note: in BT.656 mode HSYNC and VSYNC are unused */ +/* Note: in BT.656 mode HSYNC, HREF, FIELD, and VSYNC are unused */ #define V4L2_MBUS_HSYNC_ACTIVE_HIGH (1 << 2) #define V4L2_MBUS_HSYNC_ACTIVE_LOW (1 << 3) -#define V4L2_MBUS_VSYNC_ACTIVE_HIGH (1 << 4) -#define V4L2_MBUS_VSYNC_ACTIVE_LOW (1 << 5) -#define V4L2_MBUS_PCLK_SAMPLE_RISING (1 << 6) -#define V4L2_MBUS_PCLK_SAMPLE_FALLING (1 << 7) -#define V4L2_MBUS_DATA_ACTIVE_HIGH (1 << 8) -#define V4L2_MBUS_DATA_ACTIVE_LOW (1 << 9) +/* HREF is a horizontal window reference signal gating valid pixel data */ +#define V4L2_MBUS_HREF_ACTIVE_HIGH (1 << 4) +#define V4L2_MBUS_HREF_ACTIVE_LOW (1 << 5) +#define V4L2_MBUS_VSYNC_ACTIVE_HIGH (1 << 6) +#define V4L2_MBUS_VSYNC_ACTIVE_LOW (1 << 7) +#define V4L2_MBUS_PCLK_SAMPLE_RISING (1 << 8) +#define V4L2_MBUS_PCLK_SAMPLE_FALLING (1 << 9) +#define V4L2_MBUS_DATA_ACTIVE_HIGH (1 << 10) +#define V4L2_MBUS_DATA_ACTIVE_LOW (1 << 11) +/* Field selection signal for interlaced scan mode */ +#define V4L2_MBUS_FIELD_ACTIVE_HIGH (1 << 12) +#define V4L2_MBUS_FIELD_ACTIVE_LOW (1 << 13) /* Serial flags */ /* How many lanes the client can use */ -- 1.7.4.1 If there is more objection to the above changes then I'll drop the patch and stay with driver's private definitions. Thanks, -- Sylwester Nawrocki Samsung Poland R&D Center