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Subject[PATCH 7/8 resend] dw_dmac.c: Pass Channel Allocation Order from platform_data
Date
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
allocation will follow, else channels will be allocated in descending order.

Signed-off-by: Viresh Kumar <viresh.kumar@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 */
+ unsigned int chan_allocation_order;
};

/**
--
1.7.2.2


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