On Thu, 9 Nov 2017 11:54:13 +0000 Radu Andrei Alexe <radu.alexe@xxxxxxx> wrote: > On 10/30/2017 4:24 PM, Kim Phillips wrote: > > On Mon, 30 Oct 2017 15:46:51 +0200 > > Horia Geantă <horia.geanta@xxxxxxx> wrote: > > > >> +===================================================================== > >> +CAAM DMA Node > >> + > >> + Child node of the crypto node that enables the use of the DMA capabilities > >> + of the CAAM by a stand-alone driver. The only required property is the > >> + "compatible" property. All the other properties are determined from > >> + the job rings on which the CAAM DMA driver depends (ex: the number of > >> + dma-channels is equal to the number of defined job rings). > >> + > >> + - compatible > >> + Usage: required > >> + Value type: <string> > >> + Definition: Must include "fsl,sec-v4.0-dma" > >> + > >> +EXAMPLE > >> + caam-dma { > >> + compatible = "fsl,sec-v5.4-dma", > >> + "fsl,sec-v5.0-dma", > >> + "fsl,sec-v4.0-dma"; > >> + } > > > > If this isn't describing an aspect of the hardware, then what is it > > doing in the device tree? > > > > Kim > > > > Because the caam_dma driver is a platform driver I needed to create a > platform device to activate the driver. My thought was that it was > simpler to implement it using device tree. > The next patch version will create the platform device dynamically at > run time. Why create a new device when that h/w already has one? Why doesn't the existing crypto driver register dma capabilities with the dma driver subsystem? Kim -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html