On Mon, Jul 15, 2013 at 05:53:08PM +0200, Lars-Peter Clausen wrote:
> Implemnt the device_slave_caps() callback for the pl330 driver. This allows
typo ^^^^
> dmaengine users like the generic ALSA dmaengine PCM driver to query the
> capabilities of the driver. The PL330 supports all buswidths and both
> mem-to-dev as well as dev-to-mem transfers. In theory there is no limit on the
> number of segments that can be transferred (in practice you'll run out of
> memory
> eventually) and the number of bytes per segment is limited by the size of the
> PL330 program buffer. Due to the nature of the PL330 the maximum number of
> bytes
> per segment depends on the burstsize, the driver sets it to the value for a
> 1-byte burstsize, since it is the smallest.
>
> Signed-off-by: Lars-Peter Clausen <l...@metafoo.de>
> ---
> drivers/dma/pl330.c | 27 +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
> index 593827b..2bf578c 100644
> --- a/drivers/dma/pl330.c
> +++ b/drivers/dma/pl330.c
> @@ -2855,6 +2855,32 @@ static irqreturn_t pl330_irq_handler(int irq, void
> *data)
> return IRQ_NONE;
> }
>
> +#define PL330_DMA_BUSWIDTHS \
> + BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
> + BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
> + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
> + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
> + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)
checkpatch cribs that this is complex macro and should be enclosed in a
parenthesis, I have ignored it as usage doesnt justify it, yet!
> +
> +static int pl330_dma_device_slave_caps(struct dma_chan *dchan,
> + struct dma_slave_caps *caps)
> +{
> + caps->src_addr_widths = PL330_DMA_BUSWIDTHS;
> + caps->dstn_addr_widths = PL330_DMA_BUSWIDTHS;
> + caps->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
> + caps->cmd_pause = false;
> + caps->cmd_terminate = true;
> +
> + /*
trailing whitepsace here!
> + * This is the limit for transfers with a buswidth of 1, larger
> buswidths
you could have sticked to 80 char rule here very easily...
> + * will have larger limits.
> + */
Now, i am catching a plane for a work trip tomorrow, so have fixed checkpatch
and typo and applied this.
~Vinod
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
