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dmaengine: omap-dma: move reading of dma position to omap-dma.c

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Read the current DMA position from the hardware directly rather than via
arch/arm/plat-omap/dma.c.

Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2013-11-02 18:04:17 +00:00
parent fa3ad86ae0
commit 3997cab391
1 changed files with 64 additions and 2 deletions
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66
drivers/dma/omap-dma.c
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@ -427,6 +427,68 @@ static size_t omap_dma_desc_size_pos(struct omap_desc *d, dma_addr_t addr)
return size; return size;
} }
static dma_addr_t omap_dma_get_src_pos(struct omap_chan *c)
{
struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
dma_addr_t addr;
if (__dma_omap15xx(od->plat->dma_attr))
addr = c->plat->dma_read(CPC, c->dma_ch);
else
addr = c->plat->dma_read(CSAC, c->dma_ch);
if (od->plat->errata & DMA_ERRATA_3_3 && addr == 0)
addr = c->plat->dma_read(CSAC, c->dma_ch);
if (!__dma_omap15xx(od->plat->dma_attr)) {
/*
* CDAC == 0 indicates that the DMA transfer on the channel has
* not been started (no data has been transferred so far).
* Return the programmed source start address in this case.
*/
if (c->plat->dma_read(CDAC, c->dma_ch))
addr = c->plat->dma_read(CSAC, c->dma_ch);
else
addr = c->plat->dma_read(CSSA, c->dma_ch);
}
if (dma_omap1())
addr |= c->plat->dma_read(CSSA, c->dma_ch) & 0xffff0000;
return addr;
}
static dma_addr_t omap_dma_get_dst_pos(struct omap_chan *c)
{
struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
dma_addr_t addr;
if (__dma_omap15xx(od->plat->dma_attr))
addr = c->plat->dma_read(CPC, c->dma_ch);
else
addr = c->plat->dma_read(CDAC, c->dma_ch);
/*
* omap 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is
* read before the DMA controller finished disabling the channel.
*/
if (!__dma_omap15xx(od->plat->dma_attr) && addr == 0) {
addr = c->plat->dma_read(CDAC, c->dma_ch);
/*
* CDAC == 0 indicates that the DMA transfer on the channel has
* not been started (no data has been transferred so far).
* Return the programmed destination start address in this case.
*/
if (addr == 0)
addr = c->plat->dma_read(CDSA, c->dma_ch);
}
if (dma_omap1())
addr |= c->plat->dma_read(CDSA, c->dma_ch) & 0xffff0000;
return addr;
}
static enum dma_status omap_dma_tx_status(struct dma_chan *chan, static enum dma_status omap_dma_tx_status(struct dma_chan *chan,
dma_cookie_t cookie, struct dma_tx_state *txstate) dma_cookie_t cookie, struct dma_tx_state *txstate)
{ {
@ -448,9 +510,9 @@ static enum dma_status omap_dma_tx_status(struct dma_chan *chan,
dma_addr_t pos; dma_addr_t pos;
if (d->dir == DMA_MEM_TO_DEV) if (d->dir == DMA_MEM_TO_DEV)
pos = omap_get_dma_src_pos(c->dma_ch); pos = omap_dma_get_src_pos(c);
else if (d->dir == DMA_DEV_TO_MEM) else if (d->dir == DMA_DEV_TO_MEM)
pos = omap_get_dma_dst_pos(c->dma_ch); pos = omap_dma_get_dst_pos(c);
else else
pos = 0; pos = 0;