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DMAENGINE: COH 901 318 fix bytesleft

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This makes the function to get the number of bytes left in the
ongoing DMA transaction actually work: the old code did not take
neither lli:s nor queued jobs into account. Also fix a missing
spinlock while we're at it.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Linus Walleij 2010-03-04 14:40:30 +01:00 committed by Dan Williams
parent cecd87da83
commit 84c8447c54
1 changed files with 88 additions and 8 deletions
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96
drivers/dma/coh901318.c
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@ -408,25 +408,100 @@ coh901318_first_queued(struct coh901318_chan *cohc)
return d;
}
static inline u32 coh901318_get_bytes_in_lli(struct coh901318_lli *in_lli)
{
struct coh901318_lli *lli = in_lli;
u32 bytes = 0;
while (lli) {
bytes += lli->control & COH901318_CX_CTRL_TC_VALUE_MASK;
lli = lli->virt_link_addr;
}
return bytes;
}
/*
* DMA start/stop controls
* Get the number of bytes left to transfer on this channel,
* it is unwise to call this before stopping the channel for
* absolute measures, but for a rough guess you can still call
* it.
*/
u32 coh901318_get_bytes_left(struct dma_chan *chan)
{
unsigned long flags;
u32 ret;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
struct coh901318_desc *cohd;
struct list_head *pos;
unsigned long flags;
u32 left = 0;
int i = 0;
spin_lock_irqsave(&cohc->lock, flags);
/* Read transfer count value */
ret = readl(cohc->base->virtbase +
COH901318_CX_CTRL+COH901318_CX_CTRL_SPACING *
cohc->id) & COH901318_CX_CTRL_TC_VALUE_MASK;
/*
* If there are many queued jobs, we iterate and add the
* size of them all. We take a special look on the first
* job though, since it is probably active.
*/
list_for_each(pos, &cohc->active) {
/*
* The first job in the list will be working on the
* hardware. The job can be stopped but still active,
* so that the transfer counter is somewhere inside
* the buffer.
*/
cohd = list_entry(pos, struct coh901318_desc, node);
if (i == 0) {
struct coh901318_lli *lli;
dma_addr_t ladd;
/* Read current transfer count value */
left = readl(cohc->base->virtbase +
COH901318_CX_CTRL +
COH901318_CX_CTRL_SPACING * cohc->id) &
COH901318_CX_CTRL_TC_VALUE_MASK;
/* See if the transfer is linked... */
ladd = readl(cohc->base->virtbase +
COH901318_CX_LNK_ADDR +
COH901318_CX_LNK_ADDR_SPACING *
cohc->id) &
~COH901318_CX_LNK_LINK_IMMEDIATE;
/* Single transaction */
if (!ladd)
continue;
/*
* Linked transaction, follow the lli, find the
* currently processing lli, and proceed to the next
*/
lli = cohd->lli;
while (lli && lli->link_addr != ladd)
lli = lli->virt_link_addr;
if (lli)
lli = lli->virt_link_addr;
/*
* Follow remaining lli links around to count the total
* number of bytes left
*/
left += coh901318_get_bytes_in_lli(lli);
} else {
left += coh901318_get_bytes_in_lli(cohd->lli);
}
i++;
}
/* Also count bytes in the queued jobs */
list_for_each(pos, &cohc->queue) {
cohd = list_entry(pos, struct coh901318_desc, node);
left += coh901318_get_bytes_in_lli(cohd->lli);
}
spin_unlock_irqrestore(&cohc->lock, flags);
return ret;
return left;
}
EXPORT_SYMBOL(coh901318_get_bytes_left);
@ -831,6 +906,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
static int coh901318_alloc_chan_resources(struct dma_chan *chan)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
unsigned long flags;
dev_vdbg(COHC_2_DEV(cohc), "[%s] DMA channel %d\n",
__func__, cohc->id);
@ -838,11 +914,15 @@ static int coh901318_alloc_chan_resources(struct dma_chan *chan)
if (chan->client_count > 1)
return -EBUSY;
spin_lock_irqsave(&cohc->lock, flags);
coh901318_config(cohc, NULL);
cohc->allocated = 1;
cohc->completed = chan->cookie = 1;
spin_unlock_irqrestore(&cohc->lock, flags);
return 1;
}