This patch adds runtime pm support in the driver.
Signed-off-by: Kedareswara rao Appana <appanad@xxxxxxxxxx>
---
Resending the patch as there are some issues with my git send-email,
patch is not showing in the dmeengine mailing list.
Changes for v2:
--> Fixed error path in the probe.
drivers/dma/xilinx/zynqmp_dma.c | 160 ++++++++++++++++++++++++++++++++--------
1 file changed, 128 insertions(+), 32 deletions(-)
diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
index 1ee1241..4fa14bf 100644
--- a/drivers/dma/xilinx/zynqmp_dma.c
+++ b/drivers/dma/xilinx/zynqmp_dma.c
@@ -23,6 +23,7 @@
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/pm_runtime.h>
#include "../dmaengine.h"
@@ -138,6 +139,8 @@
#define ZYNQMP_DMA_BUS_WIDTH_64 64
#define ZYNQMP_DMA_BUS_WIDTH_128 128
+#define ZDMA_PM_TIMEOUT 100
+
#define ZYNQMP_DMA_DESC_SIZE(chan) (chan->desc_size)
#define to_chan(chan) container_of(chan, struct zynqmp_dma_chan, \
@@ -211,8 +214,6 @@ struct zynqmp_dma_desc_sw {
* @bus_width: Bus width
* @src_burst_len: Source burst length
* @dst_burst_len: Dest burst length
- * @clk_main: Pointer to main clock
- * @clk_apb: Pointer to apb clock
*/
struct zynqmp_dma_chan {
struct zynqmp_dma_device *zdev;
@@ -237,8 +238,6 @@ struct zynqmp_dma_chan {
u32 bus_width;
u32 src_burst_len;
u32 dst_burst_len;
- struct clk *clk_main;
- struct clk *clk_apb;
};
/**
@@ -246,11 +245,15 @@ struct zynqmp_dma_chan {
* @dev: Device Structure
* @common: DMA device structure
* @chan: Driver specific DMA channel
+ * @clk_main: Pointer to main clock
+ * @clk_apb: Pointer to apb clock
*/
struct zynqmp_dma_device {
struct device *dev;
struct dma_device common;
struct zynqmp_dma_chan *chan;
+ struct clk *clk_main;
+ struct clk *clk_apb;
};
static inline void zynqmp_dma_writeq(struct zynqmp_dma_chan *chan, u32 reg,
@@ -461,7 +464,11 @@ static int zynqmp_dma_alloc_chan_resources(struct dma_chan *dchan)
{
struct zynqmp_dma_chan *chan = to_chan(dchan);
struct zynqmp_dma_desc_sw *desc;
- int i;
+ int i, ret;
+
+ ret = pm_runtime_get_sync(chan->dev);
+ if (ret < 0)
+ return ret;
chan->sw_desc_pool = kzalloc(sizeof(*desc) * ZYNQMP_DMA_NUM_DESCS,
GFP_KERNEL);
@@ -664,6 +671,8 @@ static void zynqmp_dma_free_chan_resources(struct dma_chan *dchan)
(2 * ZYNQMP_DMA_DESC_SIZE(chan) * ZYNQMP_DMA_NUM_DESCS),
chan->desc_pool_v, chan->desc_pool_p);
kfree(chan->sw_desc_pool);
+ pm_runtime_mark_last_busy(chan->dev);
+ pm_runtime_put_autosuspend(chan->dev);
}
/**
@@ -841,8 +850,6 @@ static void zynqmp_dma_chan_remove(struct zynqmp_dma_chan *chan)
devm_free_irq(chan->zdev->dev, chan->irq, chan);
tasklet_kill(&chan->tasklet);
list_del(&chan->common.device_node);
- clk_disable_unprepare(chan->clk_apb);
- clk_disable_unprepare(chan->clk_main);
}
/**
@@ -907,30 +914,6 @@ static int zynqmp_dma_chan_probe(struct zynqmp_dma_device *zdev,
"zynqmp-dma", chan);
if (err)
return err;
- chan->clk_main = devm_clk_get(&pdev->dev, "clk_main");
- if (IS_ERR(chan->clk_main)) {
- dev_err(&pdev->dev, "main clock not found.\n");
- return PTR_ERR(chan->clk_main);
- }
-
- chan->clk_apb = devm_clk_get(&pdev->dev, "clk_apb");
- if (IS_ERR(chan->clk_apb)) {
- dev_err(&pdev->dev, "apb clock not found.\n");
- return PTR_ERR(chan->clk_apb);
- }
-
- err = clk_prepare_enable(chan->clk_main);
- if (err) {
- dev_err(&pdev->dev, "Unable to enable main clock.\n");
- return err;
- }
-
- err = clk_prepare_enable(chan->clk_apb);
- if (err) {
- clk_disable_unprepare(chan->clk_main);
- dev_err(&pdev->dev, "Unable to enable apb clock.\n");
- return err;
- }
chan->desc_size = sizeof(struct zynqmp_dma_desc_ll);
chan->idle = true;
@@ -953,6 +936,87 @@ static struct dma_chan *of_zynqmp_dma_xlate(struct of_phandle_args *dma_spec,
}
/**
+ * zynqmp_dma_suspend - Suspend method for the driver
+ * @dev: Address of the device structure
+ *
+ * Put the driver into low power mode.
+ * Return: 0 on success and failure value on error
+ */
+static int __maybe_unused zynqmp_dma_suspend(struct device *dev)
+{
+ if (!device_may_wakeup(dev))
+ return pm_runtime_force_suspend(dev);
+
+ return 0;
+}
+
+/**
+ * zynqmp_dma_resume - Resume from suspend
+ * @dev: Address of the device structure
+ *
+ * Resume operation after suspend.
+ * Return: 0 on success and failure value on error
+ */
+static int __maybe_unused zynqmp_dma_resume(struct device *dev)
+{
+ if (!device_may_wakeup(dev))
+ return pm_runtime_force_resume(dev);
+
+ return 0;
+}
+
+/**
+ * zynqmp_dma_runtime_suspend - Runtime suspend method for the driver
+ * @dev: Address of the device structure
+ *
+ * Put the driver into low power mode.
+ * Return: 0 always
+ */
+static int __maybe_unused zynqmp_dma_runtime_suspend(struct device *dev)
+{
+ struct zynqmp_dma_device *zdev = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(zdev->clk_main);
+ clk_disable_unprepare(zdev->clk_apb);
+
+ return 0;
+}
+
+/**
+ * zynqmp_dma_runtime_resume - Runtime suspend method for the driver
+ * @dev: Address of the device structure
+ *
+ * Put the driver into low power mode.
+ * Return: 0 always
+ */
+static int __maybe_unused zynqmp_dma_runtime_resume(struct device *dev)
+{
+ struct zynqmp_dma_device *zdev = dev_get_drvdata(dev);
+ int err;
+
+ err = clk_prepare_enable(zdev->clk_main);
+ if (err) {
+ dev_err(dev, "Unable to enable main clock.\n");
+ return err;
+ }
+
+ err = clk_prepare_enable(zdev->clk_apb);
+ if (err) {
+ dev_err(dev, "Unable to enable apb clock.\n");
+ clk_disable_unprepare(zdev->clk_main);
+ return err;
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops zynqmp_dma_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(zynqmp_dma_suspend, zynqmp_dma_resume)
+ SET_RUNTIME_PM_OPS(zynqmp_dma_runtime_suspend,
+ zynqmp_dma_runtime_resume, NULL)
+};
+
+/**
* zynqmp_dma_probe - Driver probe function
* @pdev: Pointer to the platform_device structure
*
@@ -984,12 +1048,33 @@ static int zynqmp_dma_probe(struct platform_device *pdev)
p->device_config = zynqmp_dma_device_config;
p->dev = &pdev->dev;
+ zdev->clk_main = devm_clk_get(&pdev->dev, "clk_main");
+ if (IS_ERR(zdev->clk_main)) {
+ dev_err(&pdev->dev, "main clock not found.\n");
+ return PTR_ERR(zdev->clk_main);
+ }
+
+ zdev->clk_apb = devm_clk_get(&pdev->dev, "clk_apb");
+ if (IS_ERR(zdev->clk_apb)) {
+ dev_err(&pdev->dev, "apb clock not found.\n");
+ return PTR_ERR(zdev->clk_apb);
+ }
+
platform_set_drvdata(pdev, zdev);
+ pm_runtime_set_autosuspend_delay(zdev->dev, ZDMA_PM_TIMEOUT);
+ pm_runtime_use_autosuspend(zdev->dev);
+ pm_runtime_enable(zdev->dev);
+ pm_runtime_get_sync(zdev->dev);
+ if (!pm_runtime_enabled(zdev->dev)) {
+ ret = zynqmp_dma_runtime_resume(zdev->dev);
+ if (ret)
+ return ret;
+ }
ret = zynqmp_dma_chan_probe(zdev, pdev);
if (ret) {
dev_err(&pdev->dev, "Probing channel failed\n");
- goto free_chan_resources;
+ goto err_disable_pm;
}
p->dst_addr_widths = BIT(zdev->chan->bus_width / 8);
@@ -1005,12 +1090,19 @@ static int zynqmp_dma_probe(struct platform_device *pdev)
goto free_chan_resources;
}
+ pm_runtime_mark_last_busy(zdev->dev);
+ pm_runtime_put_sync_autosuspend(zdev->dev);
+
dev_info(&pdev->dev, "ZynqMP DMA driver Probe success\n");
return 0;
free_chan_resources:
zynqmp_dma_chan_remove(zdev->chan);
+err_disable_pm:
+ if (!pm_runtime_enabled(zdev->dev))
+ zynqmp_dma_runtime_suspend(zdev->dev);
+ pm_runtime_disable(zdev->dev);
return ret;
}
@@ -1028,6 +1120,9 @@ static int zynqmp_dma_remove(struct platform_device *pdev)
dma_async_device_unregister(&zdev->common);
zynqmp_dma_chan_remove(zdev->chan);
+ pm_runtime_disable(zdev->dev);
+ if (!pm_runtime_enabled(zdev->dev))
+ zynqmp_dma_runtime_suspend(zdev->dev);
return 0;
}
@@ -1042,6 +1137,7 @@ static struct platform_driver zynqmp_dma_driver = {
.driver = {
.name = "xilinx-zynqmp-dma",
.of_match_table = zynqmp_dma_of_match,
+ .pm = &zynqmp_dma_dev_pm_ops,
},
.probe = zynqmp_dma_probe,
.remove = zynqmp_dma_remove,
--
2.7.4
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