Add runtime PM support to disable the clock when the h/w is not in use.
Signed-off-by: Ed Blake <ed.blake@xxxxxxxxxxx>
---
drivers/dma/img-mdc-dma.c | 82 +++++++++++++++++++++++++++++++++--------------
1 file changed, 58 insertions(+), 24 deletions(-)
diff --git a/drivers/dma/img-mdc-dma.c b/drivers/dma/img-mdc-dma.c
index ca382c9..8639f92 100644
--- a/drivers/dma/img-mdc-dma.c
+++ b/drivers/dma/img-mdc-dma.c
@@ -23,6 +23,7 @@
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
@@ -148,6 +149,9 @@ struct mdc_dma {
struct mdc_chan channels[MDC_MAX_DMA_CHANNELS];
};
+static int img_mdc_runtime_suspend(struct device *dev);
+static int img_mdc_runtime_resume(struct device *dev);
+
static inline u32 mdc_readl(struct mdc_dma *mdma, u32 reg)
{
return readl(mdma->regs + reg);
@@ -730,14 +734,23 @@ static int mdc_slave_config(struct dma_chan *chan,
return 0;
}
+static int mdc_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct mdc_chan *mchan = to_mdc_chan(chan);
+ struct device *dev = mdma2dev(mchan->mdma);
+
+ return pm_runtime_get_sync(dev);
+}
+
static void mdc_free_chan_resources(struct dma_chan *chan)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
struct mdc_dma *mdma = mchan->mdma;
+ struct device *dev = mdma2dev(mdma);
mdc_terminate_all(chan);
-
mdma->soc->disable_chan(mchan);
+ pm_runtime_put(dev);
}
static irqreturn_t mdc_chan_irq(int irq, void *dev_id)
@@ -883,10 +896,6 @@ static int mdc_dma_probe(struct platform_device *pdev)
if (IS_ERR(mdma->clk))
return PTR_ERR(mdma->clk);
- ret = clk_prepare_enable(mdma->clk);
- if (ret)
- return ret;
-
dma_cap_zero(mdma->dma_dev.cap_mask);
dma_cap_set(DMA_SLAVE, mdma->dma_dev.cap_mask);
dma_cap_set(DMA_PRIVATE, mdma->dma_dev.cap_mask);
@@ -919,12 +928,13 @@ static int mdc_dma_probe(struct platform_device *pdev)
"img,max-burst-multiplier",
&mdma->max_burst_mult);
if (ret)
- goto disable_clk;
+ return ret;
mdma->dma_dev.dev = &pdev->dev;
mdma->dma_dev.device_prep_slave_sg = mdc_prep_slave_sg;
mdma->dma_dev.device_prep_dma_cyclic = mdc_prep_dma_cyclic;
mdma->dma_dev.device_prep_dma_memcpy = mdc_prep_dma_memcpy;
+ mdma->dma_dev.device_alloc_chan_resources = mdc_alloc_chan_resources;
mdma->dma_dev.device_free_chan_resources = mdc_free_chan_resources;
mdma->dma_dev.device_tx_status = mdc_tx_status;
mdma->dma_dev.device_issue_pending = mdc_issue_pending;
@@ -945,15 +955,14 @@ static int mdc_dma_probe(struct platform_device *pdev)
mchan->mdma = mdma;
mchan->chan_nr = i;
mchan->irq = platform_get_irq(pdev, i);
- if (mchan->irq < 0) {
- ret = mchan->irq;
- goto disable_clk;
- }
+ if (mchan->irq < 0)
+ return mchan->irq;
+
ret = devm_request_irq(&pdev->dev, mchan->irq, mdc_chan_irq,
IRQ_TYPE_LEVEL_HIGH,
dev_name(&pdev->dev), mchan);
if (ret < 0)
- goto disable_clk;
+ return ret;
mchan->vc.desc_free = mdc_desc_free;
vchan_init(&mchan->vc, &mdma->dma_dev);
@@ -962,14 +971,19 @@ static int mdc_dma_probe(struct platform_device *pdev)
mdma->desc_pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
sizeof(struct mdc_hw_list_desc),
4, 0);
- if (!mdma->desc_pool) {
- ret = -ENOMEM;
- goto disable_clk;
+ if (!mdma->desc_pool)
+ return -ENOMEM;
+
+ pm_runtime_enable(&pdev->dev);
+ if (!pm_runtime_enabled(&pdev->dev)) {
+ ret = img_mdc_runtime_resume(&pdev->dev);
+ if (ret)
+ return ret;
}
ret = dma_async_device_register(&mdma->dma_dev);
if (ret)
- goto disable_clk;
+ goto suspend;
ret = of_dma_controller_register(pdev->dev.of_node, mdc_of_xlate, mdma);
if (ret)
@@ -982,8 +996,10 @@ static int mdc_dma_probe(struct platform_device *pdev)
unregister:
dma_async_device_unregister(&mdma->dma_dev);
-disable_clk:
- clk_disable_unprepare(mdma->clk);
+suspend:
+ if (!pm_runtime_enabled(&pdev->dev))
+ img_mdc_runtime_suspend(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
return ret;
}
@@ -1004,11 +1020,28 @@ static int mdc_dma_remove(struct platform_device *pdev)
tasklet_kill(&mchan->vc.task);
}
- clk_disable_unprepare(mdma->clk);
+ pm_runtime_disable(&pdev->dev);
+ if (!pm_runtime_status_suspended(&pdev->dev))
+ img_mdc_runtime_suspend(&pdev->dev);
return 0;
}
+static int img_mdc_runtime_suspend(struct device *dev)
+{
+ struct mdc_dma *mdma = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(mdma->clk);
+ return 0;
+}
+
+static int img_mdc_runtime_resume(struct device *dev)
+{
+ struct mdc_dma *mdma = dev_get_drvdata(dev);
+
+ return clk_prepare_enable(mdma->clk);
+}
+
#ifdef CONFIG_PM_SLEEP
static int img_mdc_suspend_late(struct device *dev)
{
@@ -1023,23 +1056,24 @@ static int img_mdc_suspend_late(struct device *dev)
return -EBUSY;
}
- clk_disable_unprepare(mdma->clk);
+ if (!pm_runtime_status_suspended(dev))
+ return img_mdc_runtime_suspend(dev);
return 0;
}
static int img_mdc_resume_early(struct device *dev)
{
- struct mdc_dma *mdma = dev_get_drvdata(dev);
- int ret = 0;
-
- ret = clk_prepare_enable(mdma->clk);
+ if (!pm_runtime_status_suspended(dev))
+ return img_mdc_runtime_resume(dev);
- return ret;
+ return 0;
}
#endif /* CONFIG_PM_SLEEP */
static const struct dev_pm_ops img_mdc_pm_ops = {
+ SET_RUNTIME_PM_OPS(img_mdc_runtime_suspend,
+ img_mdc_runtime_resume, NULL)
SET_LATE_SYSTEM_SLEEP_PM_OPS(img_mdc_suspend_late,
img_mdc_resume_early)
};
--
1.9.1
--
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