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 BD6BC264614; Sat, 1 Aug 2026 02:46:21 +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=1785552382; cv=none; b=jVER4izHRL0lKGKmlhq5RGzSHNurs7bBOB71HuuBX7h8qpBbuQ69L0L9k+p7EuXolaQLWflxX5XUm63yp6Aq2TKFFL9UI7d+1tCFkDXSrR2/xJ5h6feVB9Jds+MLEpYS6GYF/0Gs6YGUjOqAQ13mxuikEd8uPVZDdb5iydWJtkg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785552382; c=relaxed/simple; bh=1nf3q6IC9sTO7UFKoctJHAMBXsIQR2aGRT/RrV4jL90=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=sePDiWyONSPfPltBzR6fa0f3y8PAJmWYgU6JAiygBzI5AjCWwnOxqXTP+MjSlKFpWjD894S85m7MmI4tCKNBaGtvHLy0l+6XYfWk7h919Cq8bDONIaAMPn0+4FlmQErHNtfBUMmoGhniqsOiss2BGxOPqkpXAKqGnLkuCFsiMIw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GXvIUf0s; 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="GXvIUf0s" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 850F21F00AC4; Sat, 1 Aug 2026 02:46:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785552381; bh=EDFt6RAFrSvdpL+f6hgvwP+7xY7v8S7wuicJjSW/0xE=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=GXvIUf0ssStYRf378g3bx3JjZavrMNJWI6ilsI99/Ls6hFtLpPP9mYGhIwwkCBOHs tkX9f4+B8iwo7SKWb6u25r8OmFnJqTXzY/AdCsXDNKDy4kc01J2pZASCmzeodQGPLj 1pZwv1DW9GZRfCIOgejKRyv37gVmvgo/jlfTQY8W1K8Vn4dtS1L3FsC6bM0ZN6usLs gsA96VqOpc1mx+Ir7TTXy59uFQ8WZIsoPKuDJ8Yo1R3poRl1xMcrc2z6zSLN5Uqup3 qZZNCRtGoYK5+9sM2JAAj9DyMZW3BSJdhVzOotbWnoOc94AGHX07ayd43bbfkYjpcB 77PvTS429nmmg== Date: Sat, 1 Aug 2026 03:46:17 +0100 From: Jonathan Cameron To: Frank Li Cc: nuno.sa@analog.com, dmaengine@vger.kernel.org, linux-iio@vger.kernel.org, Vinod Koul , Frank Li , Lars-Peter Clausen , David Lechner , Andy Shevchenko Subject: Re: [PATCH 1/9] dmaengine: Support bus widths of 32 bytes and above Message-ID: <20260801034617.5dab3286@jic23-huawei> In-Reply-To: <20260801034222.45d4d479@jic23-huawei> References: <20260730-dmaengine-support-wider-dma-masks-v1-0-3732f1f9d9ca@analog.com> <20260730-dmaengine-support-wider-dma-masks-v1-1-3732f1f9d9ca@analog.com> <20260801034222.45d4d479@jic23-huawei> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Sat, 1 Aug 2026 03:42:22 +0100 Jonathan Cameron wrote: > On Thu, 30 Jul 2026 14:16:30 -0500 > Frank Li wrote: >=20 > > On Thu, Jul 30, 2026 at 03:23:08PM +0100, Nuno S=C3=A1 via B4 Relay wro= te: =20 > > > [You don't often get email from devnull+nuno.sa.analog.com@kernel.org= . Learn why this is important at https://aka.ms/LearnAboutSenderIdentificat= ion ] > > > > > > From: Nuno S=C3=A1 > > > > > > The src_addr_widths and dst_addr_widths capability masks encode each > > > supported width as a bit whose position equals the corresponding > > > enum dma_slave_buswidth value (e.g. DMA_SLAVE_BUSWIDTH_4_BYTES sets b= it > > > 4). As these masks are plain u32, widths of 32 bytes and above > > > (DMA_SLAVE_BUSWIDTH_32/64/128_BYTES map to bits 32, 64 and 128) cannot > > > be represented at all. > > > > > > Introduce bitmap-based bus width capabilities that span the full enum > > > range. To allow DMA controller producers to be converted incrementall= y, > > > keep the legacy dma_device u32 fields alongside the new bitmaps: > > > producers using the new helpers populate the bitmap and mirror the low > > > 32 bits back into the legacy field, while dma_get_slave_caps() folds a > > > legacy-only producer's u32 into the returned bitmap. > > > > > > Add helpers for producers and consumers so users do not need to depend > > > on the bitmap layout directly. Once the remaining producers are > > > converted, the legacy dma_device u32 fields can be dropped. > > > > > > Signed-off-by: Nuno S=C3=A1 > > > --- =20 > >=20 > > Reviewed-by: Frank Li =20 > https://sashiko.dev/#/patchset/20260730-dmaengine-support-wider-dma-masks= -v1-0-3732f1f9d9ca%40analog.com=20 > has a comment on this that smells plausible at least. > Looks like the stm32 driver modifies dst_bus_widths in it's device_caps() > callback. Reading on, you fix it later in series. This is going to break bisection on that device, but not build so I guess maybe fair enough to do it in this sequence. J >=20 > Jonathan >=20