Re: [RFC PATCH] dma: at_xdmac: creation of the atmel eXtended DMA Controller driver
From: Arnd Bergmann <hidden>
Date: 2014-06-10 17:58:01
Also in:
linux-arm-kernel
On Tuesday 10 June 2014 17:41:18 Maxime Ripard wrote:
quoted
+DMA clients connected to the Atmel XDMA controller must use the format +described in the dma.txt file, using a three-cell specifier for each channel: +a phandle plus two integer cells. +The three cells in order are: + +1. A phandle pointing to the DMA controller. +2. The memory interface (16 most significant bits), the peripheral interface +(16 less significant bits).Can you elaborate on this? What are they? The request IDs on both ends of the transfers?quoted
+3. Channel configuration register. Configurable fields are: + - bit 2-1: MBSIZE, memory burst size. + - bit 10-8: CSIZE, chunk size. + - bit 12-11: DWIDTH, data width.I'd rather see those as generic properties.
Actually these are standard settings that a slave driver configures using dma_slave_config. They don't belong into DT at all, as they are slave driver specific. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html