From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from twmbx01.aspeedtech.com (mail.aspeedtech.com [211.20.114.72]) (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 BA4C241DEDE; Thu, 13 Aug 2026 06:42:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=211.20.114.72 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786603374; cv=none; b=oMWG1XqoKwwnvnZvm5QOaxdQ6P5pYpPABID27Z/467AETkaRQUjpYSdvS3T7mJ5kUv9yc1BqNoHwiKmoWzdfmhCFjs963UVscq/l4UrFLVoUNiIGm8NIPiYnyr4cDroNcml2ZNyWLGwc4mU9DFAhMMIzFdOWbLg46dkMlqN9kbA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786603374; c=relaxed/simple; bh=3fvCknCwajnOMYIUp1uHwU+nFkwRbCJkD6DOdmYgiUU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=r02Oh68ntIRE/CpUFGakGTBquqT4BHrdYsrfNBhCy0maexUTEEmswjJT3zCX+ohECOEPRUm2svMdKjRJVqteaukNOISaADZj14F+eWwq5wR48/uKVtJFHtKrOoHgF3OYavqQz7JYCee3cCTqZ2E7BS5/u0cLBH2cPdwwB1Maw8Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com; spf=pass smtp.mailfrom=aspeedtech.com; arc=none smtp.client-ip=211.20.114.72 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aspeedtech.com Received: from TWMBX01.aspeed.com (192.168.0.62) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1748.10; Thu, 13 Aug 2026 14:42:33 +0800 Received: from [127.0.1.1] (192.168.10.13) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server id 15.2.1748.10 via Frontend Transport; Thu, 13 Aug 2026 14:42:33 +0800 From: Yu-Che Hsieh Date: Thu, 13 Aug 2026 14:42:31 +0800 Subject: [PATCH v2 1/2] dt-bindings: mfd: aspeed-lpc: Document lpcN alias for multi-instance SoCs Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-ID: <20260813-upstream_kcs_multiple_lpc-v2-1-775b1db3fe95@aspeedtech.com> References: <20260813-upstream_kcs_multiple_lpc-v2-0-775b1db3fe95@aspeedtech.com> In-Reply-To: <20260813-upstream_kcs_multiple_lpc-v2-0-775b1db3fe95@aspeedtech.com> To: Lee Jones , Rob Herring , "Krzysztof Kozlowski" , Conor Dooley , "Joel Stanley" , Andrew Jeffery , Chia-Wei Wang , Corey Minyard CC: Andrew Jeffery , , , , , , , Yu-Che Hsieh X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1786603353; l=1505; i=yc_hsieh@aspeedtech.com; s=20260721; h=from:subject:message-id; bh=3fvCknCwajnOMYIUp1uHwU+nFkwRbCJkD6DOdmYgiUU=; b=lJEEEpMZkfLyqypXwFJYpwz/fUf8JftwyrAnNfp+GYgwm3Cf1mwyNicBdl/HnC68WExoj+3od blHG6vR3vJdDC2zKazkTFANN2cjJE18j3DnQ6oo+qggNIRpnIzCGWTr X-Developer-Key: i=yc_hsieh@aspeedtech.com; a=ed25519; pk=7KnU2ozXGF2IATT+Hvu7RbRwPxBA3/b+zhfM+UsPJMs= 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 --- 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