Re: [PATCH v2 04/12] dt-bindings: dma: Document STM32 DMA3 controller bindings

From: Rob Herring <robh@kernel.org>
To: Amelie Delaunay <amelie.delaunay@foss.st.com>
Cc: Vinod Koul <vkoul@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>,
	dmaengine@vger.kernel.org, devicetree@vger.kernel.org,
	linux-stm32@st-md-mailman.stormreply.com,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2 04/12] dt-bindings: dma: Document STM32 DMA3 controller bindings
Date: Fri, 10 May 2024 16:08:06 -0500	[thread overview]
Message-ID: <20240510210806.GA746731-robh@kernel.org> (raw)
In-Reply-To: <20240507125442.3989284-5-amelie.delaunay@foss.st.com>

On Tue, May 07, 2024 at 02:54:34PM +0200, Amelie Delaunay wrote:
> The STM32 DMA3 is a Direct Memory Access controller with different features
> depending on its hardware configuration.
> The channels have not the same capabilities, some have a larger FIFO, so
> their performance is higher.
> This patch describes STM32 DMA3 bindings, used to select a channel that
> fits client requirements, and to pre-configure the channel depending on
> the client needs.
> 
> Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
> ---
> v2:
> - DMA controller specific information description has been moved and
>   added as description of #dma-cells property
> - description has been added to interrupts property specifying the
>   expected format for channel interrupts
> - compatible has been updated to st,stm32mp25-dma3 (SoC specific)
> ---
>  .../bindings/dma/stm32/st,stm32-dma3.yaml     | 129 ++++++++++++++++++
>  1 file changed, 129 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml
> 
> diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml
> new file mode 100644
> index 000000000000..ed2a84fe2535
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dma3.yaml
> @@ -0,0 +1,129 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/dma/stm32/st,stm32-dma3.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: STMicroelectronics STM32 DMA3 Controller
> +
> +description: |
> +  The STM32 DMA3 is a direct memory access controller with different features depending on its
> +  hardware configuration.
> +  It is either called LPDMA (Low Power), GPDMA (General Purpose) or HPDMA (High Performance).
> +  Its hardware configuration registers allow to dynamically expose its features.
> +
> +  GPDMA and HPDMA support 16 independent DMA channels, while only 4 for LPDMA.
> +  GPDMA and HPDMA support 256 DMA requests from peripherals, 8 for LPDMA.
> +
> +  Bindings are generic for these 3 STM32 DMA3 configurations.
> +
> +  DMA clients connected to the STM32 DMA3 controller must use the format described in "#dma-cells"
> +  property description below, using a three-cell specifier for each channel.

Wrap lines at 80 unless there is some exception to go to 100.

> +
> +maintainers:
> +  - Amelie Delaunay <amelie.delaunay@foss.st.com>
> +
> +allOf:
> +  - $ref: /schemas/dma/dma-controller.yaml#
> +
> +properties:
> +  compatible:
> +    const: st,stm32mp25-dma3
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    minItems: 4
> +    maxItems: 16
> +    description: |

Don't need '|' if no formatting to preserve.

With those fixed,

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>

> +      Should contain all of the per-channel DMA interrupts in ascending order with respect to the
> +      DMA channel index.