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 6308A2C3768; Thu, 6 Aug 2026 13:31:17 +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=1786023078; cv=none; b=mlLFL+YIhWa/lDIZppXTDh8ZfANob5Lnt+qn+HGLs9SC2nOhFAHsiyVLmq+d/1Z1dKql31uTUUtJIc+UWVAcpSiRAj46vmwNcjkTKgLw/Rd5vc7Mw/xQgEZkbPsX1olPZO7KJQGb+CmRRoxTweIetu2UG6tVDOsCQgWTaF2Bc+E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786023078; c=relaxed/simple; bh=naMh/yXTIuSC8ranIrocEemBRUyUTDwKVWIJS6AO/b4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=m/8oANpq6i8ZizzPrDin+dgNcX3mF5EE01XEu13DWmxSOVnit3ZH43q7pNEq/djV0ujl0kFlUwBZrT6wsqInTE9zyP0/GAYYeTnszUP93poHg7hFUoyhE98Spk5ABoaVsrOVvk8uMNBKzLjIwCMYnbNX6iXFlvcDoME9b8b+4Ck= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hJTV5eho; 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="hJTV5eho" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D1DA1F000E9; Thu, 6 Aug 2026 13:31:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786023077; bh=Y0AD+yfRRB8kFuS3umG0hhMkgfqhZmRwgX2ATJd2Akg=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=hJTV5ehoIEF8y7Kgco+X0NK8DYm3FHIb5dwVRUwRJ+mDkIY67nsnTkvehjQzkyyOE +lU0FGL1ltpTL5CrMMW5U/tDWHoyh6M2NA48HP662X36/fOLJ4+d5+Q4aq3USy6AxH jr/gGrVQkNanDlcErJfMkiKmeNFK0mBr4gAbfG2WrInh7LbSdlW8JhZtT4oAZGVHPv SmNcAUbJTJ/7JUHNGXIIhiPOzEkoGNYMl0YB+1AFQREPucGLLpdar0eSPnma2ZuwdJ txnNntcMTSk6DP5HprY8bQtNAHroh8k6MbILqDlN8MN6TBWGUpLBWQkQ4RRVsA/sb1 rildWmczV4maA== Date: Thu, 6 Aug 2026 14:31:11 +0100 From: Lee Jones To: Yu-Che Hsieh Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Joel Stanley , Andrew Jeffery , Chia-Wei Wang , Corey Minyard , Andrew Jeffery , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org, openipmi-developer@lists.sourceforge.net Subject: Re: [PATCH RFC 1/2] dt-bindings: mfd: aspeed-lpc: Document lpcN alias for multi-instance SoCs Message-ID: <20260806133111.GF2869284@google.com> References: <20260723-upstream_kcs_multiple_lpc-v1-0-d918b5270b86@aspeedtech.com> <20260723-upstream_kcs_multiple_lpc-v1-1-d918b5270b86@aspeedtech.com> Precedence: bulk X-Mailing-List: devicetree@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: <20260723-upstream_kcs_multiple_lpc-v1-1-d918b5270b86@aspeedtech.com> On Thu, 23 Jul 2026, Yu-Che Hsieh wrote: > Some SoCs (e.g. AST2700) expose more than one physical LPC controller > instance. Downstream devices such as KCS channels need a stable, > globally-unique index derived from which LPC controller instance they > belong to, so document the "lpcN" alias convention on the LPC > controller node that lets DT authors assign a fixed index per > instance, mirroring the existing alias-based numbering convention used > by mmc/i2c/spi/serial. > > Signed-off-by: Yu-Che Hsieh Why is this RFC? What's stopping me from applying this now? > --- > Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml b/Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml > index cbc3a2485a2f..81c12e0fb312 100644 > --- a/Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml > +++ b/Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml > @@ -35,6 +35,13 @@ description: > configuration, therefore the host portion of the controller is exposed as a > syscon as a means to arbitrate access. > > + On SoCs that expose more than one LPC controller instance, it is possible to > + assign a fixed index to a given instance (and thus to downstream devices > + such as KCS channels that must be uniquely identified system-wide) by > + defining an "lpcN" alias for it in the /aliases device tree node. If no such > + alias is present, the SoC is treated as having a single LPC controller > + instance. > + > properties: > compatible: > items: > > -- > 2.34.1 > -- Lee Jones