From patchwork Thu Dec 5 15:32:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ken Sloat X-Patchwork-Id: 13895573 Received: from mail-oa1-f44.google.com (mail-oa1-f44.google.com [209.85.160.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2686E1DA10C for ; Thu, 5 Dec 2024 15:32:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.44 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733412751; cv=none; b=qDzLr1RthQWFgDTnNteKJDDpIidsoOfmxZ8WaekzxeCjzG/mNWb6koLXPfh1A5JZKAfCEBy8+WnxfMK4qSDYP3FeqtgPq+bpaHTicIFmX9qHhSWHdzwXo1xAgvBbvXLDN5wWn8Vqz2tsdcVnDfEWRbVukiIzh+zcYc/1Pa6QkNU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733412751; c=relaxed/simple; bh=RbLc9FFR8wF5vdi7GcDZl88v758ckVMZlXxdmckY0ts=; h=MIME-Version:From:Date:Message-ID:Subject:To:Cc:Content-Type; b=PuLPnYFZp4JJXIocNzI5uAloKzvYGDhGHTeCYaIPYhtFUeBkCerAV0TtF9vUYZL8hMCeTD3cPntRe6hLKyp0wtiTkX1mbNzZ2+DXBHzHMosVKp5Gg4i5mlQA4+iMDzdH9DcrcdJhpjZLTKKS84f+62mie5JCkbhlqBh0TzGcvmw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cornersoftsolutions.com; spf=pass smtp.mailfrom=cornersoftsolutions.com; dkim=pass (2048-bit key) header.d=cornersoftsolutions.com header.i=@cornersoftsolutions.com header.b=Xu36Xfcp; arc=none smtp.client-ip=209.85.160.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cornersoftsolutions.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=cornersoftsolutions.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=cornersoftsolutions.com header.i=@cornersoftsolutions.com header.b="Xu36Xfcp" Received: by mail-oa1-f44.google.com with SMTP id 586e51a60fabf-29e65257182so647286fac.2 for ; Thu, 05 Dec 2024 07:32:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cornersoftsolutions.com; s=google; t=1733412749; x=1734017549; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=mSVWv3kzGyP7Ixr3DcJKWQ/Cs0NKKVxGUdtaJxvtNOU=; b=Xu36XfcpVRRV/h73WFcs2W1seMy/Plmi46O0rOsIZdXEqEX8eiejQMtMZWBMoVD+5M 4HsR+/rN3KDMauytsqMFzo+aAipi1guI/Qyqm/2zaBICtkqAX45FF7690UqzUQDlbqQE Svy+iH7nUS8ezrBLnU/2+h/Z1BHd3Z8Ejp5MStzvcODrFd0MRKsl7zlEcLPPIU3K0/AI IjM8goce/YBwxGnXmOm/HPT9T2bzLXp/CvbtadwWDS5Hf9KsSpEfFvtFEU9ZtpaSPHNz 0DTotzdCmMV+THSpvouedwhve+0b64cnzYEcOiln51hT/7cLxsO+Q1e9/Hki7NHYnoHH qxTw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733412749; x=1734017549; h=cc:to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=mSVWv3kzGyP7Ixr3DcJKWQ/Cs0NKKVxGUdtaJxvtNOU=; b=SngaNEt5E42M4mcpTo5RQZgEJukOmAQygpR/JJT21b+08AXIsfYzNIQQAMqMKLLhSL TJxlllDyBB3y4AnXWBRyVsQNT+dP6RIv9zw+awwkhfVV+vx57JjMuTj9rdN2BHl7rYGx SEw8yw5s4tvCtvyzlqtNSvzvgbbSMpKL377IeJcfHf/q3lrKoM6JLUGWSmtn6NVJG+DU RcdQUaiJUaEMSbr2KRrXFUpU4UQ9YnY9dmHtQhsvAWRjfnKZ2JuoxMAuw1V6H7fxhwC7 EhUSTFECnhN4+QSlabnoehcnPJnb1pEpyojmBCrrp5g/ewY13VGNQS9Ns7MiSYL+X+w+ IYgw== X-Forwarded-Encrypted: i=1; AJvYcCUh+pmsR98DxprJX9yLD4wbL5x3HNakVVs8ZJ60Q9j0dJI1HL8s/Iy6SXhkoc/vLIrc5TQNwpo5UkY=@vger.kernel.org X-Gm-Message-State: AOJu0Yxpk8bR1wfjS0WeKmrNGd1cDxP+jkZ6LUyVx3iexWrVmTNTSPFb ztQYK+x/dG4na+cvXTc4W1rP078a9ATvWqB9IU+P0/9rv5CUEIo1XKsGZwt2vcPy345bzJaOJvV gWZnAvqgOXbaKeXmeRMzwoxN70fFVuy1BpaLbOQ== X-Gm-Gg: ASbGncuSRiM4iBxso9lVNbs/Qp+LfD26gMOMYbnQ7RKz2mueAQ9avDLqhjN5PDt4Z3Z UXjDiAzhFplj+1iNcUsfzoPQp0EDoQv43 X-Google-Smtp-Source: AGHT+IEXh3wkarBLzAyKqYC0kT/Y8r28C1neLlKp6rQpRD5NvnZVxaGgz+SOmihpuXwnZlzhFMNga5hrHKjeRZiwzUg= X-Received: by 2002:a05:6871:606:b0:296:ee2e:a23c with SMTP id 586e51a60fabf-29e88560c9bmr11677702fac.5.1733412749132; Thu, 05 Dec 2024 07:32:29 -0800 (PST) Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Ken Sloat Date: Thu, 5 Dec 2024 10:32:17 -0500 Message-ID: Subject: [PATCH v1] dt-bindings: dma: st-stm32-dmamux: Add description for dma-cell values To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, dmaengine@vger.kernel.org, alexandre.torgue@foss.st.com, mcoquelin.stm32@gmail.com, conor+dt@kernel.org, krzk+dt@kernel.org, robh@kernel.org, vkoul@kernel.org, amelie.delaunay@foss.st.com Cc: Ken Sloat The dma-cell values for the stm32-dmamux are used to craft the DMA spec for the actual controller. These values are currently undocumented leaving the user to reverse engineer the driver in order to determine their meaning. Add a basic description, while avoiding duplicating information by pointing the user to the associated DMA docs that describe the fields in depth. Signed-off-by: Ken Sloat --- .../bindings/dma/stm32/st,stm32-dmamux.yaml | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml index f26c914a3a9a..aa2e52027ee6 100644 --- a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml @@ -15,6 +15,17 @@ allOf: properties: "#dma-cells": const: 3 + description: | + Should be set to <3> with each cell representing the following: + 1. The mux input number/line for the request + 2. Bitfield representing DMA channel configuration that is passed + to the real DMA controller + 3. Bitfield representing device dependent DMA features passed to + the real DMA controller + + For bitfield definitions of cells 2 and 3, see the associated + bindings doc for the actual DMA controller the mux is connected + to. compatible: const: st,stm32h7-dmamux -- 2.34.1