From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FB76C3402C for ; Mon, 17 Feb 2020 22:44:42 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6C41820801 for ; Mon, 17 Feb 2020 22:44:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C41820801 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E4FAF6E109; Mon, 17 Feb 2020 22:44:41 +0000 (UTC) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by gabe.freedesktop.org (Postfix) with ESMTP id 6A8EA6E109 for ; Mon, 17 Feb 2020 22:44:41 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D5FCD30E; Mon, 17 Feb 2020 14:44:40 -0800 (PST) Received: from localhost (unknown [10.37.6.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 58EF93F703; Mon, 17 Feb 2020 14:44:40 -0800 (PST) Date: Mon, 17 Feb 2020 22:44:38 +0000 From: Mark Brown To: Noralf =?iso-8859-1?Q?Tr=F8nnes?= Subject: Re: [RFC 1/9] regmap: Add USB support Message-ID: <20200217224438.GW9304@sirena.org.uk> References: <20200216172117.49832-1-noralf@tronnes.org> <20200216172117.49832-2-noralf@tronnes.org> <20200217121149.GB9304@sirena.org.uk> <20200217213911.GV9304@sirena.org.uk> <34adf00c-a465-6d6d-23bd-a2a00290c1fa@tronnes.org> MIME-Version: 1.0 In-Reply-To: <34adf00c-a465-6d6d-23bd-a2a00290c1fa@tronnes.org> X-Cookie: There was a phone call for you. User-Agent: Mutt/1.10.1 (2018-07-13) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: balbi@kernel.org, linux-usb@vger.kernel.org, lee.jones@linaro.org, dri-devel@lists.freedesktop.org Content-Type: multipart/mixed; boundary="===============2122317601==" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" --===============2122317601== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="oNLI4EWr1RPQuPCf" Content-Disposition: inline --oNLI4EWr1RPQuPCf Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Feb 17, 2020 at 11:15:37PM +0100, Noralf Tr=F8nnes wrote: > Den 17.02.2020 22.39, skrev Mark Brown: > > Out of interest why are 8 bit registers going to be a problem? > I have written 3 drivers so far and they all have some registers that > need to deal with values larger than 255. If I would need to add a lot > of code because of dropping regmap, then I would have looked at ways to > work around this in order to keep regmap, hi/lo registers perhaps with > wrapping access functions. But it looks like the LOC won't change much, > I need a few lines to ensure values are little endian, but I can also > remove some lines that's not needed anymore. Right, so you effectively have mixed register sizes which regmap isn't going to be super happy with (assuming you need all the actual display data to be 8 bit "registers"). One thing you could do there if you wanted to try the regmap route is to have multiple regmaps but since it's not clear what you're really getting from regmap other than the trace functionality you're probably right that it's not worth bothering. The only other thing I can think of is packing RGB into a single register so you're display data isn't 8 bit but that's probably not sensible from a graphics point of view (I didn't really look at that code so no idea what you're doing there). --oNLI4EWr1RPQuPCf Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl5LF1YACgkQJNaLcl1U h9C17gf+LW0MiRGt3Fci2RzupS0KkyZ3xZcQm50J9WCU00F/z7d7k5Kk/NZ6phiG OwaQx7NqVn4LqW/5u8Z61xDSQsLbSrFGxywGXZJ8XbCTlO/FKnwUdBi+CG9t2L4o 0mWT6+sxJjCG8vPjW2MREmL77ojYOwW4RHenz0rZN/lW+B3LUw5Mw3eaUbBEZU8f Zb4RsdO4yQqj1l8QPY7RcE+IuL981NUQ45GjzmJ4j7nbwn764C0bJcZYUyn3yRwJ 7tqp95eReMshjsfyhcb5OBqSEOnJO5n/XDrslxbBhLwS0zqZ2HbpYii9rzoPU8f+ 0+D0lVq2cr6XJe4CYU1V5b15BTfRcA== =LL2z -----END PGP SIGNATURE----- --oNLI4EWr1RPQuPCf-- --===============2122317601== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel --===============2122317601==--