[PATCH 7/8 resend] dw_dmac.c: Pass Channel Allocation Order from platform_data
Koul, Vinod
vinod.koul at intel.com
Wed Mar 2 13:37:54 EST 2011
On Mon, 2011-02-28 at 16:11 +0530, Viresh Kumar wrote:
> In SPEAr Platform channels 4-7 have more Fifo depth. So we must get better
> channel first. This patch introduces concept of channel allocation order in
> dw_dmac. If user doesn't paas anything or 0, than normal (ascending) channel
pass?
> allocation will follow, else channels will be allocated in descending order.
>
> Signed-off-by: Viresh Kumar <viresh.kumar at st.com>
> ---
> drivers/dma/dw_dmac.c | 6 +++++-
> include/linux/dw_dmac.h | 3 +++
> 2 files changed, 8 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
> index 01f783d..37ffd2c 100644
> --- a/drivers/dma/dw_dmac.c
> +++ b/drivers/dma/dw_dmac.c
> @@ -1314,7 +1314,11 @@ static int __init dw_probe(struct platform_device *pdev)
> dwc->chan.device = &dw->dma;
> dwc->chan.cookie = dwc->completed = 1;
> dwc->chan.chan_id = i;
> - list_add_tail(&dwc->chan.device_node, &dw->dma.channels);
> + if (pdata->chan_allocation_order == CHAN_ALLOCATION_ASCENDING)
> + list_add_tail(&dwc->chan.device_node,
> + &dw->dma.channels);
> + else
> + list_add(&dwc->chan.device_node, &dw->dma.channels);
>
> dwc->ch_regs = &__dw_regs(dw)->CHAN[i];
> spin_lock_init(&dwc->lock);
> diff --git a/include/linux/dw_dmac.h b/include/linux/dw_dmac.h
> index c8aad71..057e883 100644
> --- a/include/linux/dw_dmac.h
> +++ b/include/linux/dw_dmac.h
> @@ -19,6 +19,9 @@
> */
> struct dw_dma_platform_data {
> unsigned int nr_channels;
> +#define CHAN_ALLOCATION_ASCENDING 0 /* zero to seven */
> +#define CHAN_ALLOCATION_DESCENDING 1 /* seven to zero */
Can you add these defines outside of this struct?
> + unsigned int chan_allocation_order;
> };
>
> /**
--
~Vinod
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