From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from relay3-d.mail.gandi.net ([217.70.183.195]:59075 "EHLO relay3-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725843AbeIGMfu (ORCPT ); Fri, 7 Sep 2018 08:35:50 -0400 Date: Fri, 7 Sep 2018 09:56:00 +0200 From: jacopo mondi To: Laurent Pinchart Cc: Hugues FRUCHET , "mchehab@kernel.org" , "maxime.ripard@bootlin.com" , "sam@elite-embedded.com" , "jagan@amarulasolutions.com" , "festevam@gmail.com" , "pza@pengutronix.de" , "steve_longerbeam@mentor.com" , "loic.poulain@linaro.org" , "daniel@zonque.org" , Sakari Ailus , "linux-media@vger.kernel.org" Subject: Re: [PATCH 2/2] media: ov5640: Fix auto-exposure disabling Message-ID: <20180907075600.GL20333@w540> References: <1531912743-24767-1-git-send-email-jacopo@jmondi.org> <20180814154525.GB16349@w540> <5889322.4cUpKFCJtK@avalon> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="D9sZ58tf58331Q5M" Content-Disposition: inline In-Reply-To: <5889322.4cUpKFCJtK@avalon> Sender: linux-media-owner@vger.kernel.org List-ID: --D9sZ58tf58331Q5M Content-Type: text/plain; charset=utf-8 Content-Disposition: inline HI Laurent, On Thu, Sep 06, 2018 at 08:08:50PM +0300, Laurent Pinchart wrote: > Hello, > > On Tuesday, 14 August 2018 18:45:25 EEST jacopo mondi wrote: > > On Tue, Aug 07, 2018 at 08:53:23AM +0000, Hugues FRUCHET wrote: > > > Hi Jacopo, > > > > > > In serie "[PATCH 0/5] Fix OV5640 exposure & gain" > > > https://www.mail-archive.com/linux-media@vger.kernel.org/msg133269.html > > > I've tried to collect fixes around exposure/gain, not only the exposure > > > regression and I would prefer to keep it consistent with the associated > > > procedure test. > > > > You're right. Please see my other reply, I mixed two different issues > > in this series probably. > > > > > Moreover I dislike the internal use of control framework functions to > > > disable/enable exposure/gain, on my opinion this has to be kept simpler > > > by just disabling/enabling the right registers. > > > > Why that? I thought changing parameters exposed as controls should go > > through the control framework to ensure consistency. Maybe I'm wrong. > > If I understand the driver correctly, auto-exposure has to be disabled > temporarily when changing format and size, due to internal hardware > requirements. The sequence should more or less be > > 1. Disable auto-exposure > 2. Configure the format and size > 3. Restore auto-exposure > > This sequence is internal to the driver, and should thus not be visible to > userspace. Going through the control framework to disable and restore auto- > exposure would generate control events that would just confuse userspace. For > that reason I'd keep all this internal with direct register access instead of > going through the control framework. Thanks for the clarification. Please note this series is superseded by Hugues' exposure and gain fixes one, and my MIPI CSI-2 startup one (as it includes the timings fix also sent there). Thanks j > > > > Would it be possible that you test my 5 patches serie on your side ? > > > > I did. I re-based the series on top of my MIPI and timings fixes and > > it actually solves the exposure issues I didn't know I had :) > > > > I'll comment on v2 as well as soon as I'll get an answer from Steve on > > the CSI-2 issue. > > > > > On 07/18/2018 03:04 PM, jacopo mondi wrote: > > > > Hi again, > > > > > > > > On Wed, Jul 18, 2018 at 01:19:03PM +0200, Jacopo Mondi wrote: > > > >> As of: > > > >> commit bf4a4b518c20 ("media: ov5640: Don't force the auto exposure > > > >> state at > > > >> start time") auto-exposure got disabled before programming new capture > > > >> modes to the sensor. Unfortunately the function used to do that > > > >> (ov5640_set_exposure()) does not enable/disable auto-exposure engine > > > >> through register 0x3503[0] bit, but programs registers [0x3500 - > > > >> 0x3502] which represent the desired exposure time when running with > > > >> manual exposure. As a result, auto-exposure was not actually disabled > > > >> at all. > > > >> > > > >> To actually disable auto-exposure, go through the control framework > > > >> instead of calling ov5640_set_exposure() function directly. > > > >> > > > >> Also, as auto-gain and auto-exposure are disabled un-conditionally but > > > >> only > > > >> restored to their previous values in ov5640_set_mode_direct() function, > > > >> move controls restoring so that their value is re-programmed > > > >> opportunely after either ov5640_set_mode_direct() or > > > >> ov5640_set_mode_exposure_calc() have been executed. > > > >> > > > >> Fixes: bf4a4b518c20 ("media: ov5640: Don't force the auto exposure > > > >> state at start time") Signed-off-by: Jacopo Mondi > > > >> > > > >> --- > > > >> Is it worth doing with auto-gain what we're doing with auto-exposure? > > > >> Cache the value and then re-program it instead of unconditionally > > > >> disable/enable it?> > > > > > I have missed this patch from Hugues that address almost the same > > > > issue > > > > https://www.mail-archive.com/linux-media@vger.kernel.org/msg133264.html > > > > > > > > I feel this new one is simpler, and unless we want to avoid going > > > > through the control framework, it is not worth adding new functions to > > > > handle auto-exposure as Hugues' patch is doing. > > > > > > > > Hugues, do you have comments? Feel free to add your sob or rb tags if > > > > you like to. > > > > > > > > Thanks > > > > > > > > j > > > >> > > > >> Thanks > > > >> > > > >> j > > > >> > > > >> --- > > > >> --- > > > >> > > > >> drivers/media/i2c/ov5640.c | 29 +++++++++++++---------------- > > > >> 1 file changed, 13 insertions(+), 16 deletions(-) > > > >> > > > >> diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c > > > >> index 12b3496..bc75cb7 100644 > > > >> --- a/drivers/media/i2c/ov5640.c > > > >> +++ b/drivers/media/i2c/ov5640.c > > > >> @@ -1588,25 +1588,13 @@ static int ov5640_set_mode_exposure_calc(struct > > > >> ov5640_dev *sensor,> >> > > > >> * change mode directly > > > >> */ > > > >> > > > >> static int ov5640_set_mode_direct(struct ov5640_dev *sensor, > > > >> > > > >> - const struct ov5640_mode_info *mode, > > > >> - s32 exposure) > > > >> + const struct ov5640_mode_info *mode) > > > >> > > > >> { > > > >> > > > >> - int ret; > > > >> - > > > >> > > > >> if (!mode->reg_data) > > > >> > > > >> return -EINVAL; > > > >> > > > >> /* Write capture setting */ > > > >> > > > >> - ret = ov5640_load_regs(sensor, mode); > > > >> - if (ret < 0) > > > >> - return ret; > > > >> - > > > >> - /* turn auto gain/exposure back on for direct mode */ > > > >> - ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_gain, 1); > > > >> - if (ret) > > > >> - return ret; > > > >> - > > > >> - return __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_exp, exposure); > > > >> + return ov5640_load_regs(sensor, mode); > > > >> > > > >> } > > > >> > > > >> static int ov5640_set_mode(struct ov5640_dev *sensor, > > > >> > > > >> @@ -1626,7 +1614,7 @@ static int ov5640_set_mode(struct ov5640_dev > > > >> *sensor, > > > >> > > > >> return ret; > > > >> > > > >> exposure = sensor->ctrls.auto_exp->val; > > > >> > > > >> - ret = ov5640_set_exposure(sensor, V4L2_EXPOSURE_MANUAL); > > > >> + ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_exp, > > > >> V4L2_EXPOSURE_MANUAL); > > > >> > > > >> if (ret) > > > >> > > > >> return ret; > > > >> > > > >> @@ -1642,12 +1630,21 @@ static int ov5640_set_mode(struct ov5640_dev > > > >> *sensor,> >> > > > >> * change inside subsampling or scaling > > > >> * download firmware directly > > > >> */ > > > >> > > > >> - ret = ov5640_set_mode_direct(sensor, mode, exposure); > > > >> + ret = ov5640_set_mode_direct(sensor, mode); > > > >> > > > >> } > > > >> > > > >> if (ret < 0) > > > >> > > > >> return ret; > > > >> > > > >> + /* Restore auto-gain and auto-exposure after mode has changed. */ > > > >> + ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_gain, 1); > > > >> + if (ret) > > > >> + return ret; > > > >> + > > > >> + ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_exp, exposure) > > > >> + if (ret) > > > >> + return ret; > > > >> + > > > >> > > > >> ret = ov5640_set_binning(sensor, dn_mode != SCALING); > > > >> if (ret < 0) > > > >> > > > >> return ret; > > > >> > > > >> -- > > > >> 2.7.4 > > > -- > Regards, > > Laurent Pinchart > > > --D9sZ58tf58331Q5M Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJbki8QAAoJEHI0Bo8WoVY8J5wP/jLmJ1L1CNmDfCqVWtlT8Fyd 4oJNCzWxEFvRUnukm8f1kIxBWm/wBsT8ni+LoXTg+wE8CMK126PPDy+vIcYljefz UjpauC+jQ1ksby8aQpmfRbwzk6Lq2f9o3EjMpQTu6kan5oAUSkYM23EEpSL3zecZ 1gLlCY5MFJbdXAr2ew2ceQln+qqknSpVf3+CRPhC6cx77qkmNEtDNoUcdplFFArK aVqMSH1XLDDla1EME90+JzVPrJlC+Ds8/OnJru7tblPXfR6HU4CD8WZYSifoSaIm DeRuZZXaX4Kx6bYUbZVkUCqTmiJAXPh+gJ3xtvk2PggCHd0n63fDLstoDGzjfvtP pPHoUpM5/ZOZL7OY2lXIyTkdsiynRdDybIsd8hl5p3J8uuoNedYBx7tIlmXsXSez Y66ps22ZIctMf/sw75bxNIQj2HVqpEkbB5tMM2Qq9ij1WDr0rxwAm+qoBhdl8jvz ZOLBx3L+1gJDS5fUpxBUc7pMlcWFtJPi+iopV7nUrmI8eANxLWbeMBxfmoY7RhvY sArylAvRiV6wOcfsOZXEzUkGLg2TstGFxk1eUPYh0NKzc3RRncJ2i3ny8BvH/CZn lc+/7xU5T4nHhnVRdA+yy4YEY4+3oRsbxJeZ/bh7WR5owgxp+5wKxlih8sRQ8Vpv wc/OahqN5ifcvZqJJJR7 =URgN -----END PGP SIGNATURE----- --D9sZ58tf58331Q5M--