RE: [PATCH v27 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs and transfer-mode properties
Ryan Chen <[email protected]>
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> Subject: Re: [PATCH v27 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs > and transfer-mode properties > > On Wed, Mar 25, 2026 at 08:11:54AM +0000, Ryan Chen wrote: > > Hello Jeremy, > > Thanks the review. > > > > > Subject: Re: [PATCH v27 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add > > > global-regs and transfer-mode properties > > > > > > Hi Ryan, > > > > > > > The AST2600 I2C controller supports three transfer modes (byte, > > > > buffer, DMA). Add "aspeed,transfer-mode" so DT can select the > > > > preferred transfer method per controller instance. > > > > > > This patch does not add an aspeed,transfer-mode property. > > Will update use aspeed,enable-dma > > [...] > > > > > + aspeed,enable-dma: > > > > + type: boolean > > > > + description: | > > > > + I2C bus enable dma mode transfer. > > > > + > > > > + ASPEED ast2600 platform equipped with 16 I2C controllers > > > > +that share a > > > > + single DMA engine. DTS files can specify the data transfer > > > > +mode to/from > > > > + the device, either DMA or programmed I/O. > > > > > > As we had discussed: this does not define the transfer mode, only > > > whether DMA is available to the peripheral. > > > > > > Why mention the 16 i2c controllers here? > > > > > > Please keep this description simple and relevant to the specific > > > purpose of the property. > > > > Will update with following. > > description: Enable DMA for transfers on this I2C bus. > > You still don't understand the distinction. It's not enable, but that the h/w > instance *has* DMA capability or not. It is still up to the OS what to do with > that information. > Thanks Will update description: Indicates this I2C controller instance has DMA capability.