[PATCH v3 2/6] dmaengine: mxs: support i.MX7D and deep sleep mode

From: Han Xu
Date: Fri Aug 28 2015 - 15:42:52 EST


From: Huang Shijie <b32955@xxxxxxxxxxxxx>

The patch support i.MX7D platform by adding extra DMA clock.

Deep Sleep Mode(dsm) turns off the power for APBH DMA module, add
suspend/resume function and re-init the APBH DMA during resume.

Signed-off-by: Huang Shijie <b32955@xxxxxxxxxxxxx>
Signed-off-by: Han Xu <han.xu@xxxxxxxxxxxxx>
Signed-off-by: Adrian Alonso <aalonso@xxxxxxxxxxxxx>
---
drivers/dma/mxs-dma.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 58 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 60de352..5be13ad 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -1,5 +1,5 @@
/*
- * Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2011-2015 Freescale Semiconductor, Inc. All Rights Reserved.
*
* Refer to drivers/dma/imx-sdma.c
*
@@ -28,7 +28,6 @@
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/list.h>
-
#include <asm/irq.h>

#include "dmaengine.h"
@@ -135,6 +134,7 @@ enum mxs_dma_devtype {
enum mxs_dma_id {
IMX23_DMA,
IMX28_DMA,
+ IMX7D_DMA,
};

struct mxs_dma_engine {
@@ -142,6 +142,7 @@ struct mxs_dma_engine {
enum mxs_dma_devtype type;
void __iomem *base;
struct clk *clk;
+ struct clk *clk_io;
struct dma_device dma_device;
struct device_dma_parameters dma_parms;
struct mxs_dma_chan mxs_chans[MXS_DMA_CHANNELS];
@@ -167,6 +168,9 @@ static struct mxs_dma_type mxs_dma_types[] = {
}, {
.id = IMX28_DMA,
.type = MXS_DMA_APBX,
+ }, {
+ .id = IMX7D_DMA,
+ .type = MXS_DMA_APBH,
}
};

@@ -184,6 +188,9 @@ static const struct platform_device_id mxs_dma_ids[] = {
.name = "imx28-dma-apbx",
.driver_data = (kernel_ulong_t) &mxs_dma_types[3],
}, {
+ .name = "imx7d-dma-apbh",
+ .driver_data = (kernel_ulong_t) &mxs_dma_types[4],
+ }, {
/* end of list */
}
};
@@ -193,6 +200,7 @@ static const struct of_device_id mxs_dma_dt_ids[] = {
{ .compatible = "fsl,imx23-dma-apbx", .data = &mxs_dma_ids[1], },
{ .compatible = "fsl,imx28-dma-apbh", .data = &mxs_dma_ids[2], },
{ .compatible = "fsl,imx28-dma-apbx", .data = &mxs_dma_ids[3], },
+ { .compatible = "fsl,imx7d-dma-apbh", .data = &mxs_dma_ids[4], },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mxs_dma_dt_ids);
@@ -440,6 +448,12 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
if (ret)
goto err_clk;

+ if (mxs_dma->dev_id == IMX7D_DMA) {
+ ret = clk_prepare_enable(mxs_dma->clk_io);
+ if (ret)
+ goto err_clk_unprepare;
+ }
+
mxs_dma_reset_chan(chan);

dma_async_tx_descriptor_init(&mxs_chan->desc, chan);
@@ -450,6 +464,8 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)

return 0;

+err_clk_unprepare:
+ clk_disable_unprepare(mxs_dma->clk);
err_clk:
free_irq(mxs_chan->chan_irq, mxs_dma);
err_irq:
@@ -471,6 +487,9 @@ static void mxs_dma_free_chan_resources(struct dma_chan *chan)
dma_free_coherent(mxs_dma->dma_device.dev, CCW_BLOCK_SIZE,
mxs_chan->ccw, mxs_chan->ccw_phys);

+ if (mxs_dma->dev_id == IMX7D_DMA)
+ clk_disable_unprepare(mxs_dma->clk_io);
+
clk_disable_unprepare(mxs_dma->clk);
}

@@ -693,7 +712,7 @@ 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;

@@ -701,6 +720,12 @@ static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
if (ret)
return ret;

+ if (mxs_dma->dev_id == IMX7D_DMA) {
+ ret = clk_prepare_enable(mxs_dma->clk_io);
+ if (ret)
+ goto err_out;
+ }
+
ret = stmp_reset_block(mxs_dma->base);
if (ret)
goto err_out;
@@ -803,9 +828,19 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
if (IS_ERR(mxs_dma->base))
return PTR_ERR(mxs_dma->base);

- mxs_dma->clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(mxs_dma->clk))
- return PTR_ERR(mxs_dma->clk);
+ if (mxs_dma->dev_id == IMX7D_DMA) {
+ mxs_dma->clk = devm_clk_get(&pdev->dev, "dma_apbh_bch");
+ if (IS_ERR(mxs_dma->clk))
+ return PTR_ERR(mxs_dma->clk);
+ mxs_dma->clk_io = devm_clk_get(&pdev->dev, "dma_apbh_io");
+ if (IS_ERR(mxs_dma->clk_io))
+ return PTR_ERR(mxs_dma->clk_io);
+
+ } else {
+ mxs_dma->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(mxs_dma->clk))
+ return PTR_ERR(mxs_dma->clk);
+ }

dma_cap_set(DMA_SLAVE, mxs_dma->dma_device.cap_mask);
dma_cap_set(DMA_CYCLIC, mxs_dma->dma_device.cap_mask);
@@ -835,6 +870,7 @@ 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 +908,25 @@ 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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