[PATCH v8 2/7] dmaengine: mxs: APBH DMA supports deep sleep mode

Han Xu b45815 at freescale.com
Wed Dec 2 14:47:41 PST 2015


From: Huang Shijie <b32955 at freescale.com>

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 at freescale.com>
Signed-off-by: Han Xu <b45815 at freescale.com>
---
 drivers/dma/mxs-dma.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 60de352..eba51fc 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 +873,23 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int mxs_dma_pm_resume(struct device *dev)
+{
+	struct mxs_dma_engine *mxs_dma = dev_get_drvdata(dev);
+
+	return mxs_dma_init(mxs_dma);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+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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