[PATCH 4/8] dmaengine: ste_dma40: Do not configure channels during an channel allocation

From: Lee Jones
Date: Tue Apr 09 2013 - 14:41:15 EST


According to the DMA documentation allocating a channel and configuring
it are two separate actions. By removing the configuration code from the
channel allocation path we lighten the burden on the information required to
successfully allocate a channel.

Cc: Vinod Koul <vinod.koul@xxxxxxxxx>
Cc: Dan Williams <djbw@xxxxxx>
Cc: Per Forlin <per.forlin@xxxxxxxxxxxxxx>
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
---
drivers/dma/ste_dma40.c | 14 --------------
1 file changed, 14 deletions(-)

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 2a0a9d4..9e423ad 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -2463,16 +2463,10 @@ static int d40_alloc_chan_resources(struct dma_chan *chan)
}

pm_runtime_get_sync(d40c->base->dev);
- /* Fill in basic CFG register values */
- d40_phy_cfg(&d40c->dma_cfg, &d40c->src_def_cfg,
- &d40c->dst_def_cfg, chan_is_logical(d40c));

d40_set_prio_realtime(d40c);

if (chan_is_logical(d40c)) {
- d40_log_cfg(&d40c->dma_cfg,
- &d40c->log_def.lcsp1, &d40c->log_def.lcsp3);
-
if (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_MEM)
d40c->lcpa = d40c->base->lcpa_base +
d40c->dma_cfg.src_dev_type * D40_LCPA_CHAN_SIZE;
@@ -2487,14 +2481,6 @@ static int d40_alloc_chan_resources(struct dma_chan *chan)
d40c->phy_chan->num,
d40c->dma_cfg.use_fixed_channel ? ", fixed" : "");

-
- /*
- * Only write channel configuration to the DMA if the physical
- * resource is free. In case of multiple logical channels
- * on the same physical resource, only the first write is necessary.
- */
- if (is_free_phy)
- d40_config_write(d40c);
fail:
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
--
1.7.10.4

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