[PATCH v6 07/10] dmaengine: add dma_request_slave_channel_compat()
Arnd Bergmann
arnd at arndb.de
Wed Jan 30 04:27:18 EST 2013
On Wednesday 30 January 2013, Matt Porter wrote:
> Adds a dma_request_slave_channel_compat() wrapper which accepts
> both the arguments from dma_request_channel() and
> dma_request_slave_channel(). Based on whether the driver is
> instantiated via DT, the appropriate channel request call will be
> made.
>
> This allows for a much cleaner migration of drivers to the
> dmaengine DT API as platforms continue to be mixed between those
> that boot using DT and those that do not.
>
> Suggested-by: Tony Lindgren <tony at atomide.com>
> Signed-off-by: Matt Porter <mporter at ti.com>
> Acked-by: Tony Lindgren <tony at atomide.com>
Acked-by: Arnd Bergmann <arnd at arndb.de>
> @@ -1001,6 +1001,22 @@ void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
> struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
> struct dma_chan *net_dma_find_channel(void);
> #define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
> +#define dma_request_slave_channel_compat(mask, x, y, dev, name) \
> + __dma_request_slave_channel_compat(&(mask), x, y, dev, name)
> +
> +static inline struct dma_chan
> +*__dma_request_slave_channel_compat(dma_cap_mask_t *mask, dma_filter_fn fn,
> + void *fn_param, struct device *dev,
> + char *name)
> +{
> + struct dma_chan *chan;
> +
> + chan = dma_request_slave_channel(dev, name);
> + if (chan)
> + return chan;
> +
> + return __dma_request_channel(mask, fn, fn_param);
> +}
After I have spent some more time with implementing the code for dw_dma,
I think the mask is actually unnecessary here, the helper could just
always set it to DMA_SLAVE before calling __dma_request_channel.
It's not a bug to do it this way though, and it may help convert drivers
a little easier if there is less to change.
Arnd
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