[alsa-devel] [PATCH 1/2][RFC] dmaengine: rcar-audmapp: calculate chcr via src/dst addr

[Kuninori Morimoto]

Hi xxx

Hi Arnd

> > Current rcar-audmapp is assuming that CHCR value are specified
> > from platform data or DTS bindings. but, it is possible to
> > calculate CHCR settings from src/dst address.
> > DTS bindings node can be reduced by this patch.
> > 
> > Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
> 
> The intention definitely looks good, but I'm worried that the
> table you add here might be too SoC specific.

Thank you

> > +struct id_addr_table {
> > +	u8  id;
> > +	u16 addr;
> > +};
> > +
> > +static u32 audmapp_addr_to_id(struct device *dev, u32 addr)
> > +{
> > +	struct id_addr_table ssi_id_table[] = {
> > +		{0x00, 0x0000}, /* SSI00 */
> > +		{0x01, 0x0400}, /* SSI01 */
> > +		{0x02, 0x0800}, /* SSI02 */
> > +		{0x03, 0x0C00}, /* SSI03 */
> > +		{0x04, 0x1000}, /* SSI10 */
> > +		{0x05, 0x1400}, /* SSI11 */
> > +		{0x06, 0x1800}, /* SSI12 */
> > +		{0x07, 0x1C00}, /* SSI13 */
> > +		{0x08, 0x2000}, /* SSI20 */
> 
> Isn't the address part here the physical address of the FIFO,
> which can be different for each implementation that contains
> an audmapp device?

These are IN/OUT physical address,
and hard coded / specified for audmapp.
Other address is not supported. 

ex) 
         audmapp
  [SRCx] --------> [SSIx]
     out          in
   address      address

Best regards
---
Kuninori Morimoto