[PATCH 5/7] dmaengine: sprd: Support DMA link-list cyclic callback

From: Baolin Wang
Date: Sat Sep 29 2018 - 01:50:21 EST


From: Eric Long <eric.long@xxxxxxxxxxxxxx>

The Spreadtrum DMA link-list mode is always one cyclic transfer,
so we should clear the SPRD_DMA_LLIST_END flag for the link-list
configuration. Moreover add cyclic callback support for the cyclic
transfer.

Signed-off-by: Eric Long <eric.long@xxxxxxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
drivers/dma/sprd-dma.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index 1b39661..cefe42f 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -463,7 +463,7 @@ static irqreturn_t dma_irq_handle(int irq, void *dev_id)
struct sprd_dma_desc *sdesc;
enum sprd_dma_req_mode req_type;
enum sprd_dma_int_type int_type;
- bool trans_done = false;
+ bool trans_done = false, cyclic = false;
u32 i;

while (irq_status) {
@@ -478,13 +478,19 @@ static irqreturn_t dma_irq_handle(int irq, void *dev_id)

sdesc = schan->cur_desc;

- /* Check if the dma request descriptor is done. */
- trans_done = sprd_dma_check_trans_done(sdesc, int_type,
- req_type);
- if (trans_done == true) {
- vchan_cookie_complete(&sdesc->vd);
- schan->cur_desc = NULL;
- sprd_dma_start(schan);
+ /* cyclic mode schedule callback */
+ cyclic = schan->linklist.phy_addr ? true : false;
+ if (cyclic == true) {
+ vchan_cyclic_callback(&sdesc->vd);
+ } else {
+ /* Check if the dma request descriptor is done. */
+ trans_done = sprd_dma_check_trans_done(sdesc, int_type,
+ req_type);
+ if (trans_done == true) {
+ vchan_cookie_complete(&sdesc->vd);
+ schan->cur_desc = NULL;
+ sprd_dma_start(schan);
+ }
}
spin_unlock(&schan->vc.lock);
}
@@ -692,9 +698,6 @@ static int sprd_dma_fill_desc(struct dma_chan *chan,

/* link-list configuration */
if (schan->linklist.phy_addr) {
- if (sg_index == sglen - 1)
- hw->frg_len |= SPRD_DMA_LLIST_END;
-
hw->cfg |= SPRD_DMA_LINKLIST_EN;

/* link-list index */
--
1.7.9.5