[PATCH v6 2/7] dmaengine: mxs: APBH DMA supports deep sleep mode

From: Han Xu
Date: Thu Oct 22 2015 - 16:07:22 EST


From: Huang Shijie <b32955@xxxxxxxxxxxxx>

Deep Sleep Mode(dsm) turns off the power for APBH DMA module, DMA
need to be re-initialized when system resumed back.

Signed-off-by: Huang Shijie <b32955@xxxxxxxxxxxxx>
Signed-off-by: Han Xu <b45815@xxxxxxxxxxxxx>
---
drivers/dma/mxs-dma.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 60de352..7e5800a 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -693,7 +693,7 @@ static enum dma_status mxs_dma_tx_status(struct dma_chan *chan,
return mxs_chan->status;
}

-static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
+static int mxs_dma_init(struct mxs_dma_engine *mxs_dma)
{
int ret;

@@ -835,6 +835,7 @@ static int __init mxs_dma_probe(struct platform_device *pdev)

mxs_dma->pdev = pdev;
mxs_dma->dma_device.dev = &pdev->dev;
+ dev_set_drvdata(&pdev->dev, mxs_dma);

/* mxs_dma gets 65535 bytes maximum sg size */
mxs_dma->dma_device.dev->dma_parms = &mxs_dma->dma_parms;
@@ -872,9 +873,25 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
return 0;
}

+static int mxs_dma_pm_resume(struct device *dev)
+{
+ struct mxs_dma_engine *mxs_dma = dev_get_drvdata(dev);
+ int ret;
+
+ ret = mxs_dma_init(mxs_dma);
+ if (ret)
+ return ret;
+ return 0;
+}
+
+static const struct dev_pm_ops mxs_dma_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(NULL, mxs_dma_pm_resume)
+};
+
static struct platform_driver mxs_dma_driver = {
.driver = {
.name = "mxs-dma",
+ .pm = &mxs_dma_pm_ops,
.of_match_table = mxs_dma_dt_ids,
},
.id_table = mxs_dma_ids,
--
1.9.1

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