Hi Morimoto-san,
On Tue, Jul 15, 2014 at 12:51 PM, Simon Horman
<horms+renesas@xxxxxxxxxxxx> wrote:
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/rcar-audmapp.txt
> @@ -0,0 +1,29 @@
> +Required properties:
> +- dmas: a list of <[DMA multiplexer phandle] [SRS/DRS value]> pairs,
> + where SRS/DRS values are fixed handles, specified in the SoC
> + manual as the value that would be written into the PDMACHCR.
I think this wording is a little bit confusing.
It's not the "value that would be written into the PDMACHCR", but the
high 16-bit
part of that value, cfr. the example and the actual code below.
An alternative way of saying this could be "SRS << 8 | DRS", which clearly
shows how to combine SRS and DRS.
Unlike the docs for SYS-DMAC, which contains a table of combined MID/RID
values, the Audio DMAC-peri-peri docs contain 2 separate tables for SRS and
DRS values, so the DTS writer has to combine them manually.
> +- dma-names: a list of DMA channel names, one per "dmas" entry
> +
> +Example:
> +
> + dmas = <&audmapp 0x2d00
> + &audmapp 0x3700>;
> + dma-names = "src0_ssiu0",
> + "dvc0_ssiu0";
> --- a/drivers/dma/sh/rcar-audmapp.c
> +++ b/drivers/dma/sh/rcar-audmapp.c
> @@ -114,38 +117,50 @@ static void audmapp_start_xfer(struct shdma_chan *schan,
> audmapp_write(auchan, chcr, PDMACHCR);
> }
>
> -static struct audmapp_slave_config *
> -audmapp_find_slave(struct audmapp_chan *auchan, int slave_id)
> +static void audmapp_get_config(struct audmapp_chan *auchan, int slave_id,
> + u32 *chcr, dma_addr_t *dst)
> {
> + if (!pdata) { /* DT */
> + *chcr = ((u32)slave_id) << 16;
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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