lkml.org 
[lkml]   [2020]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3/6] dmaengine: mxs: add the power management functions
Date
add the power management functions and leverage the runtime pm for
system suspend/resume

Signed-off-by: Han Xu <han.xu@nxp.com>
---
drivers/dma/mxs-dma.c | 97 +++++++++++++++++++++++++++++++++++++++----
1 file changed, 90 insertions(+), 7 deletions(-)

diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index b458f06f9067..251492c5ea58 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -25,6 +25,7 @@
#include <linux/of_dma.h>
#include <linux/list.h>
#include <linux/dma/mxs-dma.h>
+#include <linux/pm_runtime.h>

#include <asm/irq.h>

@@ -39,6 +40,8 @@
#define dma_is_apbh(mxs_dma) ((mxs_dma)->type == MXS_DMA_APBH)
#define apbh_is_old(mxs_dma) ((mxs_dma)->dev_id == IMX23_DMA)

+#define MXS_DMA_RPM_TIMEOUT 50 /* ms */
+
#define HW_APBHX_CTRL0 0x000
#define BM_APBH_CTRL0_APB_BURST8_EN (1 << 29)
#define BM_APBH_CTRL0_APB_BURST_EN (1 << 28)
@@ -416,6 +419,7 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
+ struct device *dev = &mxs_dma->pdev->dev;
int ret;

mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev,
@@ -431,9 +435,11 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
if (ret)
goto err_irq;

- ret = clk_prepare_enable(mxs_dma->clk);
- if (ret)
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ dev_err(dev, "Failed to enable clock\n");
goto err_clk;
+ }

mxs_dma_reset_chan(chan);

@@ -458,6 +464,7 @@ static void mxs_dma_free_chan_resources(struct dma_chan *chan)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
+ struct device *dev = &mxs_dma->pdev->dev;

mxs_dma_disable_chan(chan);

@@ -466,7 +473,9 @@ 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);

- clk_disable_unprepare(mxs_dma->clk);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
}

/*
@@ -689,14 +698,32 @@ 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_rpm(struct mxs_dma_engine *mxs_dma)
{
+ struct device *dev = &mxs_dma->pdev->dev;
+
+ pm_runtime_enable(dev);
+ pm_runtime_set_autosuspend_delay(dev, MXS_DMA_RPM_TIMEOUT);
+ pm_runtime_use_autosuspend(dev);
+
+ return 0;
+}
+
+static int mxs_dma_init(struct mxs_dma_engine *mxs_dma)
+{
+ struct device *dev = &mxs_dma->pdev->dev;
int ret;

- ret = clk_prepare_enable(mxs_dma->clk);
+ ret = mxs_dma_init_rpm(mxs_dma);
if (ret)
return ret;

+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ dev_err(dev, "Failed to enable clock\n");
+ return ret;
+ }
+
ret = stmp_reset_block(mxs_dma->base);
if (ret)
goto err_out;
@@ -714,7 +741,8 @@ static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
mxs_dma->base + HW_APBHX_CTRL1 + STMP_OFFSET_REG_SET);

err_out:
- clk_disable_unprepare(mxs_dma->clk);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
return ret;
}

@@ -821,11 +849,13 @@ static int mxs_dma_probe(struct platform_device *pdev)
&mxs_dma->dma_device.channels);
}

+ platform_set_drvdata(pdev, mxs_dma);
+ mxs_dma->pdev = pdev;
+
ret = mxs_dma_init(mxs_dma);
if (ret)
return ret;

- mxs_dma->pdev = pdev;
mxs_dma->dma_device.dev = &pdev->dev;

/* mxs_dma gets 65535 bytes maximum sg size */
@@ -879,9 +909,62 @@ static int mxs_dma_remove(struct platform_device *pdev)
return 0;
}

+#ifdef CONFIG_PM_SLEEP
+static int mxs_dma_pm_suspend(struct device *dev)
+{
+ int ret;
+
+ ret = pm_runtime_force_suspend(dev);
+
+ return ret;
+}
+
+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;
+}
+#endif
+
+int mxs_dma_runtime_suspend(struct device *dev)
+{
+ struct mxs_dma_engine *mxs_dma = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(mxs_dma->clk);
+
+ return 0;
+}
+
+int mxs_dma_runtime_resume(struct device *dev)
+{
+ struct mxs_dma_engine *mxs_dma = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_prepare_enable(mxs_dma->clk);
+ if (ret) {
+ dev_err(&mxs_dma->pdev->dev, "failed to enable the clock\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops mxs_dma_pm_ops = {
+ SET_RUNTIME_PM_OPS(mxs_dma_runtime_suspend,
+ mxs_dma_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(mxs_dma_pm_suspend, 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,
--
2.17.1
\
 
 \ /
  Last update: 2020-01-14 22:49    [W:0.104 / U:23.864 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site