From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0E3623F413B; Thu, 14 May 2026 08:01:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778745675; cv=none; b=kOYWdKp6CE8LcAFQwpF+vBn2UhbfdLv4HW/ZkE8C+ipUZY8NogmBE8/5Ik5i69iRwmyscq0w2xIuWla/+KSLHfBVB5SsAi6zcHevvsQUBmbD7NPb6zu7kw6Ut+r0dRxMx0P0pK5KZbHs968mTcmQod6ZozazDyjiTTPwF4WeCVk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778745675; c=relaxed/simple; bh=LBjYh0WyTrCmwMWHfUohe1fuFl6BoJ/p5bOEjPTnQKU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PrFOpsbPK+7YsfjEQjTL+/hPKlBnDfUOUBFabx9vsSrt5Dbv12RIp2Xl80vhDk8Y4+1120gdS70nAzzM1HLooHpJZAFjYc4hEtjTaGt8I6/wAbcc2zPfBnphfXNDafHbsS8A6rK0d5B4yHMz9tYFnVNUyDy9G452tCIhdIsXGjc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=D+L4ENID; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="D+L4ENID" Received: from ideasonboard.com (net-93-65-100-155.cust.vodafonedsl.it [93.65.100.155]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 3BB811283; Thu, 14 May 2026 10:01:03 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1778745663; bh=LBjYh0WyTrCmwMWHfUohe1fuFl6BoJ/p5bOEjPTnQKU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=D+L4ENIDLel4nvuFIOeYw7UR3zh80t5L5evdJnQTHezjNCN1VsOfmGKft6YsSWIr7 vqEi9Bq8sx3oowCWYEVhHccO+kJquf1PDaHkZ2lVorwWaAgpl6hW+ZM0JvhF5KI0as G0WUkYnTr+C69q7FlZ2KZvHAROtz8t1bh7IK24Xk= Date: Thu, 14 May 2026 10:01:09 +0200 From: Jacopo Mondi To: Jacopo Mondi Cc: Kieran Bingham , Sakari Ailus , Steve Longerbeam , Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 02/11] media: i2c: ov5640: Set exposure minimum and defaults Message-ID: References: <20260501-ov5640_cleanup-v1-0-0869a7802a33@ideasonboard.com> <20260501-ov5640_cleanup-v1-2-0869a7802a33@ideasonboard.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Thu, May 14, 2026 at 09:58:43AM +0200, Jacopo Mondi wrote: > Hi Kieran > > On Fri, May 01, 2026 at 04:39:04PM +0100, Kieran Bingham wrote: > > A zero exposure would be a fully black image and not useful as a sensor. > > Increase the minimum and default control values to sane parameters. > > > > Signed-off-by: Kieran Bingham > > --- > > drivers/media/i2c/ov5640.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c > > index 01ea6b2bfeeb..b5e529ea662b 100644 > > --- a/drivers/media/i2c/ov5640.c > > +++ b/drivers/media/i2c/ov5640.c > > @@ -3479,7 +3479,7 @@ static int ov5640_init_controls(struct ov5640_dev *sensor) > > V4L2_EXPOSURE_MANUAL, 0, > > V4L2_EXPOSURE_AUTO); > > ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE, > > - 0, 65535, 1, 0); > > + 4, 65535, 1, 1000); > > Where does 1000 come from ? The register default is 512, should we use > that value ? > > Also, is the 4 lines step value correct ? Sorry, this is the minimum of course. How did you pick 4 ? > > > /* Auto/manual gain */ > > ctrls->auto_gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_AUTOGAIN, > > 0, 1, 1, 1); > > > > -- > > 2.52.0 > > > >