dmaengine: at_hdmac: improve power management routines
Save/restore dma controller state across a suspend-resume sequence.
The prepare() function will wait for the non-cyclic channels to become idle.
It also deals with cyclic operations with the start at next period while
resuming.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/at_hdmac_regs.h b/drivers/dma/at_hdmac_regs.h
index 087dbf1..6f0c4a3 100644
--- a/drivers/dma/at_hdmac_regs.h
+++ b/drivers/dma/at_hdmac_regs.h
@@ -204,6 +204,9 @@
* @status: transmit status information from irq/prep* functions
* to tasklet (use atomic operations)
* @tasklet: bottom half to finish transaction work
+ * @save_cfg: configuration register that is saved on suspend/resume cycle
+ * @save_dscr: for cyclic operations, preserve next descriptor address in
+ * the cyclic list on suspend/resume cycle
* @lock: serializes enqueue/dequeue operations to descriptors lists
* @completed_cookie: identifier for the most recently completed operation
* @active_list: list of descriptors dmaengine is being running on
@@ -218,6 +221,8 @@
u8 mask;
unsigned long status;
struct tasklet_struct tasklet;
+ u32 save_cfg;
+ u32 save_dscr;
spinlock_t lock;
@@ -248,6 +253,7 @@
* @chan_common: common dmaengine dma_device object members
* @ch_regs: memory mapped register base
* @clk: dma controller clock
+ * @save_imr: interrupt mask register that is saved on suspend/resume cycle
* @all_chan_mask: all channels availlable in a mask
* @dma_desc_pool: base of DMA descriptor region (DMA address)
* @chan: channels table to store at_dma_chan structures
@@ -256,6 +262,7 @@
struct dma_device dma_common;
void __iomem *regs;
struct clk *clk;
+ u32 save_imr;
u8 all_chan_mask;