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

[Arnd Bergmann <arnd@arndb.de>]

On Thursday 29 January 2015 01:24:06 Kuninori Morimoto wrote:
> 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@renesas.com>

The intention definitely looks good, but I'm worried that the
table you add here might be too SoC specific.

> +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?

	Arnd