From: Aisheng Dong <aisheng.dong@xxxxxxx>
Flexcan will be disabled during suspend if no wakeup function required and
enabled after resume accordingly. During this period, we could explicitly
disable clocks.
Implement Runtime PM which will:
1) Keep device in suspend state (clocks disabled) if it's not openned.
2) Make Power Domain framework be able to shutdown the corresponding power
domain of this device.
Signed-off-by: Aisheng Dong <aisheng.dong@xxxxxxx>
Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
---
ChangeLog:
V1->V2:
*rebased on patch "can: flexcan: add self wakeup support".
*add check when to do flexcan_clks_disable/enable() during
Runtime PM.
---
drivers/net/can/flexcan.c | 119 ++++++++++++++++++++++++--------------
1 file changed, 77 insertions(+), 42 deletions(-)
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index d12b2f7d2834..130a2cb04827 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -24,6 +24,7 @@
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/regmap.h>
@@ -277,6 +278,7 @@ struct flexcan_priv {
u32 reg_imask1_default;
u32 reg_imask2_default;
+ struct device *dev;
struct clk *clk_ipg;
struct clk *clk_per;
const struct flexcan_devtype_data *devtype_data;
@@ -444,6 +446,27 @@ static inline void flexcan_error_irq_disable(const struct flexcan_priv *priv)
priv->write(reg_ctrl, ®s->ctrl);
}
+static int flexcan_clks_enable(const struct flexcan_priv *priv)
+{
+ int err;
+
+ err = clk_prepare_enable(priv->clk_ipg);
+ if (err)
+ return err;
+
+ err = clk_prepare_enable(priv->clk_per);
+ if (err)
+ clk_disable_unprepare(priv->clk_ipg);
+
+ return err;
+}
+
+static void flexcan_clks_disable(const struct flexcan_priv *priv)
+{
+ clk_disable_unprepare(priv->clk_ipg);
+ clk_disable_unprepare(priv->clk_per);
+}
+
static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
{
if (!priv->reg_xceiver)
@@ -570,19 +593,11 @@ static int flexcan_get_berr_counter(const struct net_device *dev,
const struct flexcan_priv *priv = netdev_priv(dev);
int err;
- err = clk_prepare_enable(priv->clk_ipg);
- if (err)
- return err;
-
- err = clk_prepare_enable(priv->clk_per);
- if (err)
- goto out_disable_ipg;
+ pm_runtime_get_sync(priv->dev);
err = __flexcan_get_berr_counter(dev, bec);
- clk_disable_unprepare(priv->clk_per);
- out_disable_ipg:
- clk_disable_unprepare(priv->clk_ipg);
+ pm_runtime_put(priv->dev);
return err;
}
@@ -1215,17 +1230,13 @@ static int flexcan_open(struct net_device *dev)
struct flexcan_priv *priv = netdev_priv(dev);
int err;
- err = clk_prepare_enable(priv->clk_ipg);
+ err = pm_runtime_get_sync(priv->dev);
if (err)
return err;
- err = clk_prepare_enable(priv->clk_per);
- if (err)
- goto out_disable_ipg;
-
err = open_candev(dev);
if (err)
- goto out_disable_per;
+ goto out_pm_runtime;
err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
if (err)
@@ -1288,10 +1299,8 @@ static int flexcan_open(struct net_device *dev)
free_irq(dev->irq, dev);
out_close:
close_candev(dev);
- out_disable_per:
- clk_disable_unprepare(priv->clk_per);
- out_disable_ipg:
- clk_disable_unprepare(priv->clk_ipg);
+ out_pm_runtime:
+ pm_runtime_put(priv->dev);
return err;
}
@@ -1306,11 +1315,11 @@ static int flexcan_close(struct net_device *dev)
can_rx_offload_del(&priv->offload);
free_irq(dev->irq, dev);
- clk_disable_unprepare(priv->clk_per);
- clk_disable_unprepare(priv->clk_ipg);
close_candev(dev);
+ pm_runtime_put(priv->dev);
+
can_led_event(dev, CAN_LED_EVENT_STOP);
return 0;
@@ -1349,18 +1358,10 @@ static int register_flexcandev(struct net_device *dev)
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg, err;
- err = clk_prepare_enable(priv->clk_ipg);
- if (err)
- return err;
-
- err = clk_prepare_enable(priv->clk_per);
- if (err)
- goto out_disable_ipg;
-
/* select "bus clock", chip must be disabled */
err = flexcan_chip_disable(priv);
if (err)
- goto out_disable_per;
+ return err;
reg = priv->read(®s->ctrl);
reg |= FLEXCAN_CTRL_CLK_SRC;
priv->write(reg, ®s->ctrl);
@@ -1389,13 +1390,8 @@ static int register_flexcandev(struct net_device *dev)
err = register_candev(dev);
- /* disable core and turn off clocks */
out_chip_disable:
flexcan_chip_disable(priv);
- out_disable_per:
- clk_disable_unprepare(priv->clk_per);
- out_disable_ipg:
- clk_disable_unprepare(priv->clk_ipg);
return err;
}
@@ -1556,6 +1552,7 @@ static int flexcan_probe(struct platform_device *pdev)
priv->write = flexcan_write_le;
}
+ priv->dev = &pdev->dev;
priv->can.clock.freq = clock_freq;
priv->can.bittiming_const = &flexcan_bittiming_const;
priv->can.do_set_mode = flexcan_set_mode;
@@ -1569,14 +1566,23 @@ static int flexcan_probe(struct platform_device *pdev)
priv->devtype_data = devtype_data;
priv->reg_xceiver = reg_xceiver;
+ pm_runtime_enable(&pdev->dev);
+ err = pm_runtime_get_sync(&pdev->dev);
+ if (err < 0) {
+ dev_err(&pdev->dev, "pm_runtime_get failed(%d)\n", err);
+ goto failed_rpm_disable;
+ }
+
err = register_flexcandev(dev);
if (err) {
dev_err(&pdev->dev, "registering netdev failed\n");
- goto failed_register;
+ goto failed_rpm_put;
}
devm_can_led_init(dev);
+ pm_runtime_put(&pdev->dev);
+
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE) {
err = flexcan_setup_stop_mode(pdev);
if (err)
@@ -1588,8 +1594,11 @@ static int flexcan_probe(struct platform_device *pdev)
return 0;
- failed_register:
+ failed_rpm_put:
+ pm_runtime_put(&pdev->dev);
free_candev(dev);
+ failed_rpm_disable:
+ pm_runtime_disable(&pdev->dev);
return err;
}
@@ -1598,6 +1607,7 @@ static int flexcan_remove(struct platform_device *pdev)
struct net_device *dev = platform_get_drvdata(pdev);
unregister_flexcandev(dev);
+ pm_runtime_disable(&pdev->dev);
free_candev(dev);
return 0;
@@ -1607,7 +1617,7 @@ static int __maybe_unused flexcan_suspend(struct device *device)
{
struct net_device *dev = dev_get_drvdata(device);
struct flexcan_priv *priv = netdev_priv(dev);
- int err;
+ int err = 0;
if (netif_running(dev)) {
/* if wakeup is enabled, enter stop mode
@@ -1620,20 +1630,21 @@ static int __maybe_unused flexcan_suspend(struct device *device)
err = flexcan_chip_disable(priv);
if (err)
return err;
+ err = pm_runtime_force_suspend(device);
}
netif_stop_queue(dev);
netif_device_detach(dev);
}
priv->can.state = CAN_STATE_SLEEPING;
- return 0;
+ return err;
}
static int __maybe_unused flexcan_resume(struct device *device)
{
struct net_device *dev = dev_get_drvdata(device);
struct flexcan_priv *priv = netdev_priv(dev);
- int err;
+ int err = 0;
priv->can.state = CAN_STATE_ERROR_ACTIVE;
if (netif_running(dev)) {
@@ -1642,11 +1653,34 @@ static int __maybe_unused flexcan_resume(struct device *device)
if (device_may_wakeup(device)) {
disable_irq_wake(dev->irq);
} else {
- err = flexcan_chip_enable(priv);
+ err = pm_runtime_force_resume(device);
if (err)
return err;
+ err = flexcan_chip_enable(priv);
}
}
+ return err;
+}
+
+static int __maybe_unused flexcan_runtime_suspend(struct device *device)
+{
+ struct net_device *dev = dev_get_drvdata(device);
+ struct flexcan_priv *priv = netdev_priv(dev);
+
+ if (netif_running(dev))
+ flexcan_clks_disable(priv);
+
+ return 0;
+}
+
+static int __maybe_unused flexcan_runtime_resume(struct device *device)
+{
+ struct net_device *dev = dev_get_drvdata(device);
+ struct flexcan_priv *priv = netdev_priv(dev);
+
+ if (!netif_running(dev))
+ flexcan_clks_enable(priv);
+
return 0;
}
@@ -1676,6 +1710,7 @@ static int __maybe_unused flexcan_noirq_resume(struct device *device)
static const struct dev_pm_ops flexcan_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(flexcan_suspend, flexcan_resume)
+ SET_RUNTIME_PM_OPS(flexcan_runtime_suspend, flexcan_runtime_resume, NULL)
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(flexcan_noirq_suspend, flexcan_noirq_resume)
};
--
2.17.1
