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authorRussell King <rmk+kernel@arm.linux.org.uk>2012-05-11 02:45:24 +0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2012-07-01 17:16:25 +0400
commit63fe23c34e1c18725bd1459897bf3a46335d88b7 (patch)
tree2b0b806dda260ccd075e1747834669022516434b /drivers/dma
parent571fa74034701391b1be2ad193f684acfdeb75d1 (diff)
downloadlinux-63fe23c34e1c18725bd1459897bf3a46335d88b7.tar.xz
dmaengine: sa11x0-dma: fix DMA residue support
The semantics now implemented are: - If the cookie has completed successfully, the residue will be zero. - If the cookie is in progress or the channel is paused, it will be the number of bytes yet to be transferred. [*] - If the cookie is queued, it will be the number of bytes in the descriptor. * - where this is the number of bytes yet to be transferred to/from RAM. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/dma')
-rw-r--r--drivers/dma/sa11x0-dma.c45
1 files changed, 29 insertions, 16 deletions
diff --git a/drivers/dma/sa11x0-dma.c b/drivers/dma/sa11x0-dma.c
index 5f1d2e670837..db4fcbd80c7d 100644
--- a/drivers/dma/sa11x0-dma.c
+++ b/drivers/dma/sa11x0-dma.c
@@ -416,27 +416,47 @@ static enum dma_status sa11x0_dma_tx_status(struct dma_chan *chan,
struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
struct sa11x0_dma_phy *p;
- struct sa11x0_dma_desc *txd;
+ struct virt_dma_desc *vd;
unsigned long flags;
enum dma_status ret;
- size_t bytes = 0;
ret = dma_cookie_status(&c->vc.chan, cookie, state);
if (ret == DMA_SUCCESS)
return ret;
+ if (!state)
+ return c->status;
+
spin_lock_irqsave(&c->vc.lock, flags);
p = c->phy;
- ret = c->status;
- if (p) {
- dma_addr_t addr = sa11x0_dma_pos(p);
- dev_vdbg(d->slave.dev, "tx_status: addr:%x\n", addr);
+ /*
+ * If the cookie is on our issue queue, then the residue is
+ * its total size.
+ */
+ vd = vchan_find_desc(&c->vc, cookie);
+ if (vd) {
+ state->residue = container_of(vd, struct sa11x0_dma_desc, vd)->size;
+ } else if (!p) {
+ state->residue = 0;
+ } else {
+ struct sa11x0_dma_desc *txd;
+ size_t bytes = 0;
+
+ if (p->txd_done && p->txd_done->vd.tx.cookie == cookie)
+ txd = p->txd_done;
+ else if (p->txd_load && p->txd_load->vd.tx.cookie == cookie)
+ txd = p->txd_load;
+ else
+ txd = NULL;
- txd = p->txd_done;
+ ret = c->status;
if (txd) {
+ dma_addr_t addr = sa11x0_dma_pos(p);
unsigned i;
+ dev_vdbg(d->slave.dev, "tx_status: addr:%x\n", addr);
+
for (i = 0; i < txd->sglen; i++) {
dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x\n",
i, txd->sg[i].addr, txd->sg[i].len);
@@ -459,18 +479,11 @@ static enum dma_status sa11x0_dma_tx_status(struct dma_chan *chan,
bytes += txd->sg[i].len;
}
}
- if (txd != p->txd_load && p->txd_load)
- bytes += p->txd_load->size;
- }
- list_for_each_entry(txd, &c->vc.desc_issued, vd.node) {
- bytes += txd->size;
+ state->residue = bytes;
}
spin_unlock_irqrestore(&c->vc.lock, flags);
- if (state)
- state->residue = bytes;
-
- dev_vdbg(d->slave.dev, "tx_status: bytes 0x%zx\n", bytes);
+ dev_vdbg(d->slave.dev, "tx_status: bytes 0x%zx\n", state->residue);
return ret;
}