Skip to content

Commit

Permalink
dmaengine: at_xdmac: introduce save_cc field
Browse files Browse the repository at this point in the history
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@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
  • Loading branch information
Ludovic Desroches authored and Vinod Koul committed Feb 5, 2015
1 parent cbb85e6 commit 734bb9a
Showing 1 changed file with 3 additions and 3 deletions.
6 changes: 3 additions & 3 deletions drivers/dma/at_xdmac.c
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand Down Expand Up @@ -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);
Expand All @@ -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);

Expand All @@ -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);
Expand Down

0 comments on commit 734bb9a

Please sign in to comment.