From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=213.167.242.64 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792584327; b=wnRr8aIYc72/Mypd0a9FyePsKkWmoWUxMAMDVak8sAXyimZLBJvpexyFPbxy/sw+bayX SSGxfBa8E3AGTCqtIA26onbAIEKwW3iyP1izYFkDwJ27DcJxSsNh/JTRMNdAdRA/gHCZe mWBfs3rwjpftjDTfJf3WmQbxK1bdRCd19B3aZAW1ewnTmHqT0eyhWZfnACb8WROMtIico uatM7UqqQKvIp5Knzh99gzh+4IQNCVEyFwdqg2CiW2c/cQROvzGkx8tgCNWfyY7MGA5n7 kkdpSlavQNHT+F56OqRwwZq6x1zGnz76K7GVH0z7eMLWVjovXzI2gKnmAXnjPhxqAKQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792584327; h=DMARC-Filter:Received:DKIM-Signature:Date:From:To:Cc:Subject: Message-ID:References:MIME-Version:Content-Type:Content-Disposition: In-Reply-To; bh=O61xCztn16+CXQnXsR44bdFGXvhE9RH8gNBloavPbF0=; b=qoKj4XMQKL2zNlb5/B/2+NN6BDCx/3IeCwTfKtGO4NbDjIaH8FY/HWa31ofmd7OoGqrf K0S9+T4wsGPsgq6IiJvg3gvGNCjhwo0im/rQLoW/2WtDUsCFMXYDWbhv08SOvIdlproo9 SYJMk/VTIYtAwrwxdCNfqvEhevoFNOP7IOiPg2Bn3/YIqb069TAK2jSvLC+sE7KqEwXjw fpxHPZAcKxuaEe2SSRz+nl8XAF0/99ZMdC6IYHXYrWaE7qXVHKdMKYRl0ZAkEP9KFzCds kj9lrB9POkcqUJKcWWlMkuOGWKUuQVu8fhIfPs7dTNhIzB064cem3knIPYR9QWzL5LQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass header.d=ideasonboard.com header.i=@ideasonboard.com header.a=rsa-sha256 header.s=mail header.b="B/MBRnAI"; arc=none smtp.remote-ip=213.167.242.64 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2C359606A31A; Wed, 21 Oct 2026 12:05:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 2C359606A31A 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, unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.a=rsa-sha256 header.s=mail header.b=B/MBRnAI Received: from killaraus.ideasonboard.com (2001-14ba-70f3-e800--a06.rev.dnainternet.fi [IPv6:2001:14ba:70f3:e800::a06]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 13F841F8; Wed, 21 Oct 2026 14:03:15 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1792584195; bh=yj25+04SNewszu7HyA3/Agpl6CsSY9REc1aQTeuyfqA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=B/MBRnAIffrF2sWUzabo7wzt3nUNy3A1DjS7krugH8cg3EaZz5GzxhCWtegJRr/wL MuA9YIrcIO03Azjr60Daeu4AD7398haa+ivusRKGQISE4HDNAexIL0GkQEox9LzcsL 1FEEjT6ytrgCYLv1zfxotxpC3ezR2PXKz7jr+osA= Date: Wed, 21 Oct 2026 15:05:21 +0300 From: Laurent Pinchart To: Sakari Ailus Cc: Dave Stevenson , Lachlan Michael , mchehab@kernel.org, hverkuil+cisco@kernel.org, linux-media@vger.kernel.org, devicetree@vger.kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, kieran.bingham@ideasonboard.com, jai.luthra@ideasonboard.com, Ryuichi.Tadano@sony.com, Kengo.Hayasaka@sony.com, Tim.Bird2@sony.com, Kazumi.A.Sato@sony.com, Yuji.John.Takahashi@sony.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 2/2] media: i2c: Add Sony IMX908 image sensor driver Message-ID: <20261021120521.GA273922@killaraus.ideasonboard.com> References: <20261019014720.2635-1-lachlan.michael@sony.com> <20261019014720.2635-3-lachlan.michael@sony.com> <20261020125630.GA158670@killaraus.ideasonboard.com> X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Wed, Oct 21, 2026 at 02:56:50PM +0300, Sakari Ailus wrote: > On Tue, Oct 20, 2026 at 03:50:09PM +0100, Dave Stevenson wrote: > > On Tue, 20 Oct 2026 at 13:56, Laurent Pinchart wrote: > > > On Tue, Oct 20, 2026 at 01:47:11PM +0300, Sakari Ailus wrote: > > > > On Mon, Oct 19, 2026 at 10:47:20AM +0900, Lachlan Michael wrote: > > > > > The IMX908 is an 8.39 MP (3856x2176) CMOS image sensor with a MIPI CSI-2 > > > > > output interface. The driver supports RAW10 and RAW12 output formats, > > > > > exposure and analogue gain controls, image flipping, blanking controls > > > > > and test pattern generation. > > > > > > > > The imx908 appears to be a Starvis 3 sensor. How close is it to the Starvis > > > > 2, for which Dave (Cc'd) is working on a driver (see > > > > )? > > > > The register defines in the two drivers appear to be quite well aligned. > > > > Asked and answered at v1 > > https://lore.kernel.org/linux-media/TY6PR01MB17839FF48671E744E7E23A93E92D42@TY6PR01MB17839.jpnprd01.prod.outlook.com/ > > > > > The current version of the driver implements very few features of the > > > IMX908 sensor, as crop support has been removed pending the raw camera > > > sensor model, and Clear HDR3 is being developed. I expect more > > > differences to appear when those features will be merged, so I believe > > > it makes sense to have a separate driver here. > > > > > > In the future, I expect the raw camera sensor model to open the door to > > > more code sharing and more drivers supporting a wider variety of > > > devices. We can decide then if the imx908 should stay a standalone > > > driver, support other sensors as well, possibly across the Starvis 2 and > > > 3 families. I'm willing to help with the refactoring at that point if > > > needed, the maintenance burden won't be on you (and I'm sure that > > > Lachlan and his team will of course maintain the code base). > > > > Agreed. > > I have compared the datasheet for imx908 against the Starvis2 ones, > > and when we start looking at HDR modes they diverge a reasonable > > amount. > > > > Even the later Starvis2 sensors (IMX585 and IMX676) have minor changes > > to the earlier ones, so adding Starvis3 would need some care. > > There's quite a bit of this in the CCS driver, due to the variance it > allows for implementors. I don't see this being a problem as long as the > foundations are reasonably similar, albeit we can see whether this could be > further extended later on to other sensors. > > I'm fine with having a separate imx908 driver for now. Dave's driver also > exposes the variant information through the media entity name so that > should be done by the imx908, too (at least if there can be multiple ones). As far as I understand, the IMX908 does not have a mono version. Lachlan, could you please confirm that ? > I'll review the driver properly soonish but I reckon it's in a pretty good > shape already. -- Regards, Laurent Pinchart