[PATCH v2 2/4] dmaengine: at_xdmac: introduce save_cc field
Ludovic Desroches
ludovic.desroches at atmel.com
Fri Dec 12 02:36:53 PST 2014
When suspending the device, read the channel configuration directly from
the register instead of relying on a software snapshot, it will be
safer.
Signed-off-by: Ludovic Desroches <ludovic.desroches at atmel.com>
---
drivers/dma/at_xdmac.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index bc4b018..5c4f877 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -200,6 +200,7 @@ struct at_xdmac_chan {
u8 memif; /* Memory Interface */
u32 per_src_addr;
u32 per_dst_addr;
+ u32 save_cc;
u32 save_cim;
u32 save_cnda;
u32 save_cndc;
@@ -1276,6 +1277,7 @@ static int atmel_xdmac_suspend(struct device *dev)
list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
if (at_xdmac_chan_is_cyclic(atchan)) {
if (!at_xdmac_chan_is_paused(atchan))
at_xdmac_device_pause(chan);
@@ -1298,7 +1300,6 @@ static int atmel_xdmac_resume(struct device *dev)
struct at_xdmac_chan *atchan;
struct dma_chan *chan, *_chan;
int i;
- u32 cfg;
clk_prepare_enable(atxdmac->clk);
@@ -1313,8 +1314,7 @@ static int atmel_xdmac_resume(struct device *dev)
at_xdmac_write(atxdmac, AT_XDMAC_GE, atxdmac->save_gs);
list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
atchan = to_at_xdmac_chan(chan);
- cfg = atchan->cfg[AT_XDMAC_CUR_CFG];
- at_xdmac_chan_write(atchan, AT_XDMAC_CC, cfg);
+ at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
if (at_xdmac_chan_is_cyclic(atchan)) {
at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
--
2.0.3
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