From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 217ED2C21FD; Fri, 18 Sep 2026 20:00:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789761637; cv=none; b=R8b+0P+cTcaU5eW4cVvmpZb/pKuleLB17alYLrMYHKUrEu7m7izM3XIHKtW1mSv/+I21p9GWqCrjq+TFOI71iaC8b4uK+M6YoRvq0ysJxRzuU5awALAKN1BEyh5WTHdgHKtqmIE+UEkxmSg4yvQf2ptV5GiWbTZqdV0HKC8RRmw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789761637; c=relaxed/simple; bh=4TzoEpfHRdH7xCT//qpK8wJr7qb0NkkYV7wvZfAGVO8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VVdSCl+gv6SjmF+OMitqX6SHQ4rOCydusnrM6N3oA8RBe2o1mpVUdhue0FBJcddoWokK7K2IigfsclXaUE5uhsO2yCBeoHguHrQ1D3VrsSeQ2dbvp5F1PUN99t/XAvyyP5C5PoNtrBS7mwOeZyW3ri2h6Mr5nwwS/sXTNvTSwWs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jpn5n0zi; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jpn5n0zi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 844491F00898; Fri, 18 Sep 2026 20:00:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789761635; bh=OsEpDB9UCJuLpaU3+bqZ1MTcVZYu+7Pxx8NDDG4f60Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=jpn5n0zi7D/eHOm0AMqqerqvuIxBgyPrCcGty/49OY9O+kJLzGV1WKcxvAAT42mzv 69Cb1NQfGn6RW2MhgaJoKePHUOhjoKIlupzn58+FvrxmVwOiH0zi3+Ot2j1B2jOqUd YBLsDfpodoqPUYqXXekWL+ZBUESnwubHyLvKsiueJNVqEtlogz/Rr8zvTVuqU8+/bP cPWD7Z42W7q0Y4OSiFIXA4V8CnQycALYuu8V+juyYaKzZeqSo64O76MkJ3PMbwEXM7 6vEPD+HcnAA1ICD/jFhLxgwLOTdgIEn1DpAlwwonoKAFRP5sDm453v6rkyFwki2SOu 1jtST1+Kpq2cw== Date: Fri, 18 Sep 2026 15:00:33 -0500 From: Rob Herring To: Geert Uytterhoeven Cc: Mark Brown , Krzysztof Kozlowski , Conor Dooley , Marek Vasut , linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Geert Uytterhoeven , kernel test robot Subject: Re: [PATCH] spi: dt-bindings: Relax node name suffixes again Message-ID: <20260918200033.GA1667835-robh@kernel.org> References: <60988ce9c4913014e255ecbe127e93374f6a2295.1789570538.git.geert@linux-m68k.org> Precedence: bulk X-Mailing-List: linux-renesas-soc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <60988ce9c4913014e255ecbe127e93374f6a2295.1789570538.git.geert@linux-m68k.org> On Wed, Sep 16, 2026 at 05:18:27PM +0200, Geert Uytterhoeven wrote: > From: Geert Uytterhoeven > > An SPI bus node name can have either a unit address, or a suffix. > Commit c4fb6880edc15866 ("spi: dt-bindings: restrict node name > suffixes") restricted these suffixes to decimal numbers. > However, SPI bus node names with suffixes are typically used for > board-level bit-banged SPI busses ("spi-gpio"), which live at the root > of the device tree. Limiting their node names to numbers is prone to > conflicts, and may cause silent overwrites, especially when a stack of > sub-boards or expansion boards is involved. How is that commit an issue 3 years later? I've commented on the case which I guess prompted this patch. BTW, "spi-gpio" or "i2c-gpio" are not good names because you can have more than 1 instance. > > Hence relax node name suffixes to alphanumerical characters, so users > can write more descriptive SPI bus names, which are less prone to > conflicts. > > While at it, reject empty unit addresses. > > Reported-by: kernel test robot > Closes: https://lore.kernel.org/oe-kbuild-all/202609150228.Nh4nZzbQ-lkp@intel.com > Signed-off-by: Geert Uytterhoeven > --- > Other subsystems (regulator, i2c) had similar issues, and numbered > regulators caused conflicts before, see e.g. commit 45f5d5a9e34d3fe4 > ("arm64: dts: renesas: r8a77995: draak: Fix backlight regulator name"). I2C was a case of "too many to fix". Maybe time to revisit that. Regulator binding is a unicorn and not a bus. I really want standard names for buses given that's the only way to identify them generically. Rob