| Message ID | 1445577818-26165-1-git-send-email-appanad@xilinx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 10/23/2015 07:23 AM, Kedareswara rao Appana wrote: > Instead of enabling/disabling clocks at several locations in the driver, > Use the runtime_pm framework. This consolidates the actions for runtime PM > In the appropriate callbacks and makes the driver more readable and mantainable. > > Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com> > --- > Changes for v7: > - Removed the unnecessary clk_prepare/clk_unprepare calls > From the probe and remove as suggested by Soren. > Changes for v6: > - Updated the driver with review comments as suggested by Marc. > Changes for v5: > - Updated with the review comments. > Updated the remove fuction to use runtime_pm. > Chnages for v4: > - Updated with the review comments. > Changes for v3: > - Converted the driver to use runtime_pm. > Changes for v2: > - Removed the struct platform_device* from suspend/resume > as suggest by Lothar. > > drivers/net/can/xilinx_can.c | 177 +++++++++++++++++++++++++------------------ > 1 file changed, 102 insertions(+), 75 deletions(-) > > diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c > index fc55e8e..fcb584f 100644 > --- a/drivers/net/can/xilinx_can.c > +++ b/drivers/net/can/xilinx_can.c > @@ -32,6 +32,7 @@ > #include <linux/can/dev.h> > #include <linux/can/error.h> > #include <linux/can/led.h> > +#include <linux/pm_runtime.h> > > #define DRIVER_NAME "xilinx_can" > > @@ -138,7 +139,7 @@ struct xcan_priv { > u32 (*read_reg)(const struct xcan_priv *priv, enum xcan_reg reg); > void (*write_reg)(const struct xcan_priv *priv, enum xcan_reg reg, > u32 val); > - struct net_device *dev; > + struct device *dev; > void __iomem *reg_base; > unsigned long irq_flags; > struct clk *bus_clk; > @@ -843,6 +844,13 @@ static int xcan_open(struct net_device *ndev) > struct xcan_priv *priv = netdev_priv(ndev); > int ret; > > + ret = pm_runtime_get_sync(priv->dev); > + if (ret < 0) { > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > + __func__, ret); > + return ret; > + } > + > ret = request_irq(ndev->irq, xcan_interrupt, priv->irq_flags, > ndev->name, ndev); > if (ret < 0) { > @@ -850,29 +858,17 @@ static int xcan_open(struct net_device *ndev) > goto err; > } > > - ret = clk_prepare_enable(priv->can_clk); > - if (ret) { > - netdev_err(ndev, "unable to enable device clock\n"); > - goto err_irq; > - } > - > - ret = clk_prepare_enable(priv->bus_clk); > - if (ret) { > - netdev_err(ndev, "unable to enable bus clock\n"); > - goto err_can_clk; > - } > - > /* Set chip into reset mode */ > ret = set_reset_mode(ndev); > if (ret < 0) { > netdev_err(ndev, "mode resetting failed!\n"); > - goto err_bus_clk; > + goto err_irq; > } > > /* Common open */ > ret = open_candev(ndev); > if (ret) > - goto err_bus_clk; > + goto err_irq; > > ret = xcan_chip_start(ndev); > if (ret < 0) { > @@ -888,13 +884,11 @@ static int xcan_open(struct net_device *ndev) > > err_candev: > close_candev(ndev); > -err_bus_clk: > - clk_disable_unprepare(priv->bus_clk); > -err_can_clk: > - clk_disable_unprepare(priv->can_clk); > err_irq: > free_irq(ndev->irq, ndev); > err: > + pm_runtime_put(priv->dev); > + > return ret; > } > > @@ -911,12 +905,11 @@ static int xcan_close(struct net_device *ndev) > netif_stop_queue(ndev); > napi_disable(&priv->napi); > xcan_chip_stop(ndev); > - clk_disable_unprepare(priv->bus_clk); > - clk_disable_unprepare(priv->can_clk); > free_irq(ndev->irq, ndev); > close_candev(ndev); > > can_led_event(ndev, CAN_LED_EVENT_STOP); > + pm_runtime_put(priv->dev); > > return 0; > } > @@ -935,27 +928,20 @@ static int xcan_get_berr_counter(const struct net_device *ndev, > struct xcan_priv *priv = netdev_priv(ndev); > int ret; > > - ret = clk_prepare_enable(priv->can_clk); > - if (ret) > - goto err; > - > - ret = clk_prepare_enable(priv->bus_clk); > - if (ret) > - goto err_clk; > + ret = pm_runtime_get_sync(priv->dev); > + if (ret < 0) { > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > + __func__, ret); > + return ret; > + } > > bec->txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK; > bec->rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) & > XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT); > > - clk_disable_unprepare(priv->bus_clk); > - clk_disable_unprepare(priv->can_clk); > + pm_runtime_put(priv->dev); > > return 0; > - > -err_clk: > - clk_disable_unprepare(priv->can_clk); > -err: > - return ret; > } > > > @@ -968,15 +954,45 @@ static const struct net_device_ops xcan_netdev_ops = { > > /** > * xcan_suspend - Suspend method for the driver > - * @dev: Address of the platform_device structure > + * @dev: Address of the device structure > * > * Put the driver into low power mode. > - * Return: 0 always > + * Return: 0 on success and failure value on error > */ > static int __maybe_unused xcan_suspend(struct device *dev) > { > - struct platform_device *pdev = dev_get_drvdata(dev); > - struct net_device *ndev = platform_get_drvdata(pdev); > + if (!device_may_wakeup(dev)) > + return pm_runtime_force_suspend(dev); > + > + return 0; > +} > + > +/** > + * xcan_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 xcan_resume(struct device *dev) > +{ > + if (!device_may_wakeup(dev)) > + return pm_runtime_force_resume(dev); > + > + return 0; > + > +} > + > +/** > + * xcan_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 xcan_runtime_suspend(struct device *dev) > +{ > + struct net_device *ndev = dev_get_drvdata(dev); > struct xcan_priv *priv = netdev_priv(ndev); > > if (netif_running(ndev)) { > @@ -987,43 +1003,55 @@ static int __maybe_unused xcan_suspend(struct device *dev) > priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK); > priv->can.state = CAN_STATE_SLEEPING; > > - clk_disable(priv->bus_clk); > - clk_disable(priv->can_clk); > + clk_disable_unprepare(priv->bus_clk); > + clk_disable_unprepare(priv->can_clk); > > return 0; > } > > /** > - * xcan_resume - Resume from suspend > - * @dev: Address of the platformdevice structure > + * xcan_runtime_resume - Runtime 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 xcan_resume(struct device *dev) > +static int __maybe_unused xcan_runtime_resume(struct device *dev) > { > - struct platform_device *pdev = dev_get_drvdata(dev); > - struct net_device *ndev = platform_get_drvdata(pdev); > + struct net_device *ndev = dev_get_drvdata(dev); > struct xcan_priv *priv = netdev_priv(ndev); > int ret; > + u32 isr, status; > > - ret = clk_enable(priv->bus_clk); > + ret = clk_prepare_enable(priv->bus_clk); > if (ret) { > dev_err(dev, "Cannot enable clock.\n"); > return ret; > } > - ret = clk_enable(priv->can_clk); > + ret = clk_prepare_enable(priv->can_clk); > if (ret) { > dev_err(dev, "Cannot enable clock.\n"); > clk_disable_unprepare(priv->bus_clk); > return ret; > } > > - priv->write_reg(priv, XCAN_MSR_OFFSET, 0); > - priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_CEN_MASK); > - priv->can.state = CAN_STATE_ERROR_ACTIVE; > + priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK); > + isr = priv->read_reg(priv, XCAN_ISR_OFFSET); > + status = priv->read_reg(priv, XCAN_SR_OFFSET); > > if (netif_running(ndev)) { > + if (isr & XCAN_IXR_BSOFF_MASK) { > + priv->can.state = CAN_STATE_BUS_OFF; > + priv->write_reg(priv, XCAN_SRR_OFFSET, > + XCAN_SRR_RESET_MASK); > + } else if ((status & XCAN_SR_ESTAT_MASK) == > + XCAN_SR_ESTAT_MASK) { > + priv->can.state = CAN_STATE_ERROR_PASSIVE; > + } else if (status & XCAN_SR_ERRWRN_MASK) { > + priv->can.state = CAN_STATE_ERROR_WARNING; > + } else { > + priv->can.state = CAN_STATE_ERROR_ACTIVE; > + } > netif_device_attach(ndev); > netif_start_queue(ndev); > } > @@ -1031,7 +1059,10 @@ static int __maybe_unused xcan_resume(struct device *dev) > return 0; > } > > -static SIMPLE_DEV_PM_OPS(xcan_dev_pm_ops, xcan_suspend, xcan_resume); > +static const struct dev_pm_ops xcan_dev_pm_ops = { > + SET_SYSTEM_SLEEP_PM_OPS(xcan_suspend, xcan_resume) > + SET_RUNTIME_PM_OPS(xcan_runtime_suspend, xcan_runtime_resume, NULL) > +}; > > /** > * xcan_probe - Platform registration call > @@ -1072,7 +1103,7 @@ static int xcan_probe(struct platform_device *pdev) > return -ENOMEM; > > priv = netdev_priv(ndev); > - priv->dev = ndev; > + priv->dev = &pdev->dev; > priv->can.bittiming_const = &xcan_bittiming_const; > priv->can.do_set_mode = xcan_do_set_mode; > priv->can.do_get_berr_counter = xcan_get_berr_counter; > @@ -1114,21 +1145,18 @@ static int xcan_probe(struct platform_device *pdev) > } > } > > - ret = clk_prepare_enable(priv->can_clk); > - if (ret) { > - dev_err(&pdev->dev, "unable to enable device clock\n"); > - goto err_free; > - } > - > - ret = clk_prepare_enable(priv->bus_clk); > - if (ret) { > - dev_err(&pdev->dev, "unable to enable bus clock\n"); > - goto err_unprepare_disable_dev; > - } > - > priv->write_reg = xcan_write_reg_le; > priv->read_reg = xcan_read_reg_le; > > + pm_runtime_irq_safe(&pdev->dev); Have you tested the patch with lockdep enabled? clk_prepare_enable() can sleep and pm_runtime_irq_safe() says that's it's ok to call the code from atomic context. Either remove the pm_runtime_irq_safe() or only call the clk_enable(), clk_disable in the RM runtime handlers. > + pm_runtime_enable(&pdev->dev); > + ret = pm_runtime_get_sync(&pdev->dev); > + if (ret < 0) { > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > + __func__, ret); > + goto err_pmdisable; > + } > + > if (priv->read_reg(priv, XCAN_SR_OFFSET) != XCAN_SR_CONFIG_MASK) { > priv->write_reg = xcan_write_reg_be; > priv->read_reg = xcan_read_reg_be; > @@ -1141,22 +1169,23 @@ static int xcan_probe(struct platform_device *pdev) > ret = register_candev(ndev); > if (ret) { > dev_err(&pdev->dev, "fail to register failed (err=%d)\n", ret); > - goto err_unprepare_disable_busclk; > + goto err_disableclks; > } > > devm_can_led_init(ndev); > - clk_disable_unprepare(priv->bus_clk); > - clk_disable_unprepare(priv->can_clk); > + > + pm_runtime_put(&pdev->dev); > + > netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo depth:%d\n", > priv->reg_base, ndev->irq, priv->can.clock.freq, > priv->tx_max); > > return 0; > > -err_unprepare_disable_busclk: > - clk_disable_unprepare(priv->bus_clk); > -err_unprepare_disable_dev: > - clk_disable_unprepare(priv->can_clk); > +err_disableclks: > + pm_runtime_put(priv->dev); > +err_pmdisable: > + pm_runtime_disable(&pdev->dev); > err_free: > free_candev(ndev); > err: > @@ -1175,10 +1204,8 @@ static int xcan_remove(struct platform_device *pdev) > struct net_device *ndev = platform_get_drvdata(pdev); > struct xcan_priv *priv = netdev_priv(ndev); > > - if (set_reset_mode(ndev) < 0) > - netdev_err(ndev, "mode resetting failed!\n"); > - > unregister_candev(ndev); > + pm_runtime_disable(&pdev->dev); > netif_napi_del(&priv->napi); > free_candev(ndev); > > Marc
Hi Marc, > -----Original Message----- > From: Marc Kleine-Budde [mailto:mkl@pengutronix.de] > Sent: Monday, October 26, 2015 1:54 AM > To: Appana Durga Kedareswara Rao; Anirudha Sarangi; wg@grandegger.com; > Michal Simek; Soren Brinkmann > Cc: linux-can@vger.kernel.org; netdev@vger.kernel.org; linux-arm- > kernel@lists.infradead.org; linux-kernel@vger.kernel.org; Appana Durga > Kedareswara Rao > Subject: Re: [PATCH v7] can: xilinx: Convert to runtime_pm > > On 10/23/2015 07:23 AM, Kedareswara rao Appana wrote: > > Instead of enabling/disabling clocks at several locations in the > > driver, Use the runtime_pm framework. This consolidates the actions > > for runtime PM In the appropriate callbacks and makes the driver more > readable and mantainable. > > > > Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com> > > --- > > Changes for v7: > > - Removed the unnecessary clk_prepare/clk_unprepare calls > > From the probe and remove as suggested by Soren. > > Changes for v6: > > - Updated the driver with review comments as suggested by Marc. > > Changes for v5: > > - Updated with the review comments. > > Updated the remove fuction to use runtime_pm. > > Chnages for v4: > > - Updated with the review comments. > > Changes for v3: > > - Converted the driver to use runtime_pm. > > Changes for v2: > > - Removed the struct platform_device* from suspend/resume > > as suggest by Lothar. > > > > drivers/net/can/xilinx_can.c | 177 > > +++++++++++++++++++++++++------------------ > > 1 file changed, 102 insertions(+), 75 deletions(-) > > > > diff --git a/drivers/net/can/xilinx_can.c > > b/drivers/net/can/xilinx_can.c index fc55e8e..fcb584f 100644 > > --- a/drivers/net/can/xilinx_can.c > > +++ b/drivers/net/can/xilinx_can.c > > @@ -32,6 +32,7 @@ > > #include <linux/can/dev.h> > > #include <linux/can/error.h> > > #include <linux/can/led.h> > > +#include <linux/pm_runtime.h> > > > > #define DRIVER_NAME "xilinx_can" > > > > @@ -138,7 +139,7 @@ struct xcan_priv { > > u32 (*read_reg)(const struct xcan_priv *priv, enum xcan_reg reg); > > void (*write_reg)(const struct xcan_priv *priv, enum xcan_reg reg, > > u32 val); > > - struct net_device *dev; > > + struct device *dev; > > void __iomem *reg_base; > > unsigned long irq_flags; > > struct clk *bus_clk; > > @@ -843,6 +844,13 @@ static int xcan_open(struct net_device *ndev) > > struct xcan_priv *priv = netdev_priv(ndev); > > int ret; > > > > + ret = pm_runtime_get_sync(priv->dev); > > + if (ret < 0) { > > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > > + __func__, ret); > > + return ret; > > + } > > + > > ret = request_irq(ndev->irq, xcan_interrupt, priv->irq_flags, > > ndev->name, ndev); > > if (ret < 0) { > > @@ -850,29 +858,17 @@ static int xcan_open(struct net_device *ndev) > > goto err; > > } > > > > - ret = clk_prepare_enable(priv->can_clk); > > - if (ret) { > > - netdev_err(ndev, "unable to enable device clock\n"); > > - goto err_irq; > > - } > > - > > - ret = clk_prepare_enable(priv->bus_clk); > > - if (ret) { > > - netdev_err(ndev, "unable to enable bus clock\n"); > > - goto err_can_clk; > > - } > > - > > /* Set chip into reset mode */ > > ret = set_reset_mode(ndev); > > if (ret < 0) { > > netdev_err(ndev, "mode resetting failed!\n"); > > - goto err_bus_clk; > > + goto err_irq; > > } > > > > /* Common open */ > > ret = open_candev(ndev); > > if (ret) > > - goto err_bus_clk; > > + goto err_irq; > > > > ret = xcan_chip_start(ndev); > > if (ret < 0) { > > @@ -888,13 +884,11 @@ static int xcan_open(struct net_device *ndev) > > > > err_candev: > > close_candev(ndev); > > -err_bus_clk: > > - clk_disable_unprepare(priv->bus_clk); > > -err_can_clk: > > - clk_disable_unprepare(priv->can_clk); > > err_irq: > > free_irq(ndev->irq, ndev); > > err: > > + pm_runtime_put(priv->dev); > > + > > return ret; > > } > > > > @@ -911,12 +905,11 @@ static int xcan_close(struct net_device *ndev) > > netif_stop_queue(ndev); > > napi_disable(&priv->napi); > > xcan_chip_stop(ndev); > > - clk_disable_unprepare(priv->bus_clk); > > - clk_disable_unprepare(priv->can_clk); > > free_irq(ndev->irq, ndev); > > close_candev(ndev); > > > > can_led_event(ndev, CAN_LED_EVENT_STOP); > > + pm_runtime_put(priv->dev); > > > > return 0; > > } > > @@ -935,27 +928,20 @@ static int xcan_get_berr_counter(const struct > net_device *ndev, > > struct xcan_priv *priv = netdev_priv(ndev); > > int ret; > > > > - ret = clk_prepare_enable(priv->can_clk); > > - if (ret) > > - goto err; > > - > > - ret = clk_prepare_enable(priv->bus_clk); > > - if (ret) > > - goto err_clk; > > + ret = pm_runtime_get_sync(priv->dev); > > + if (ret < 0) { > > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > > + __func__, ret); > > + return ret; > > + } > > > > bec->txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & > XCAN_ECR_TEC_MASK; > > bec->rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) & > > XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT); > > > > - clk_disable_unprepare(priv->bus_clk); > > - clk_disable_unprepare(priv->can_clk); > > + pm_runtime_put(priv->dev); > > > > return 0; > > - > > -err_clk: > > - clk_disable_unprepare(priv->can_clk); > > -err: > > - return ret; > > } > > > > > > @@ -968,15 +954,45 @@ static const struct net_device_ops > > xcan_netdev_ops = { > > > > /** > > * xcan_suspend - Suspend method for the driver > > - * @dev: Address of the platform_device structure > > + * @dev: Address of the device structure > > * > > * Put the driver into low power mode. > > - * Return: 0 always > > + * Return: 0 on success and failure value on error > > */ > > static int __maybe_unused xcan_suspend(struct device *dev) { > > - struct platform_device *pdev = dev_get_drvdata(dev); > > - struct net_device *ndev = platform_get_drvdata(pdev); > > + if (!device_may_wakeup(dev)) > > + return pm_runtime_force_suspend(dev); > > + > > + return 0; > > +} > > + > > +/** > > + * xcan_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 xcan_resume(struct device *dev) { > > + if (!device_may_wakeup(dev)) > > + return pm_runtime_force_resume(dev); > > + > > + return 0; > > + > > +} > > + > > +/** > > + * xcan_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 xcan_runtime_suspend(struct device *dev) { > > + struct net_device *ndev = dev_get_drvdata(dev); > > struct xcan_priv *priv = netdev_priv(ndev); > > > > if (netif_running(ndev)) { > > @@ -987,43 +1003,55 @@ static int __maybe_unused xcan_suspend(struct > device *dev) > > priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK); > > priv->can.state = CAN_STATE_SLEEPING; > > > > - clk_disable(priv->bus_clk); > > - clk_disable(priv->can_clk); > > + clk_disable_unprepare(priv->bus_clk); > > + clk_disable_unprepare(priv->can_clk); > > > > return 0; > > } > > > > /** > > - * xcan_resume - Resume from suspend > > - * @dev: Address of the platformdevice structure > > + * xcan_runtime_resume - Runtime 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 xcan_resume(struct device *dev) > > +static int __maybe_unused xcan_runtime_resume(struct device *dev) > > { > > - struct platform_device *pdev = dev_get_drvdata(dev); > > - struct net_device *ndev = platform_get_drvdata(pdev); > > + struct net_device *ndev = dev_get_drvdata(dev); > > struct xcan_priv *priv = netdev_priv(ndev); > > int ret; > > + u32 isr, status; > > > > - ret = clk_enable(priv->bus_clk); > > + ret = clk_prepare_enable(priv->bus_clk); > > if (ret) { > > dev_err(dev, "Cannot enable clock.\n"); > > return ret; > > } > > - ret = clk_enable(priv->can_clk); > > + ret = clk_prepare_enable(priv->can_clk); > > if (ret) { > > dev_err(dev, "Cannot enable clock.\n"); > > clk_disable_unprepare(priv->bus_clk); > > return ret; > > } > > > > - priv->write_reg(priv, XCAN_MSR_OFFSET, 0); > > - priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_CEN_MASK); > > - priv->can.state = CAN_STATE_ERROR_ACTIVE; > > + priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK); > > + isr = priv->read_reg(priv, XCAN_ISR_OFFSET); > > + status = priv->read_reg(priv, XCAN_SR_OFFSET); > > > > if (netif_running(ndev)) { > > + if (isr & XCAN_IXR_BSOFF_MASK) { > > + priv->can.state = CAN_STATE_BUS_OFF; > > + priv->write_reg(priv, XCAN_SRR_OFFSET, > > + XCAN_SRR_RESET_MASK); > > + } else if ((status & XCAN_SR_ESTAT_MASK) == > > + XCAN_SR_ESTAT_MASK) { > > + priv->can.state = CAN_STATE_ERROR_PASSIVE; > > + } else if (status & XCAN_SR_ERRWRN_MASK) { > > + priv->can.state = CAN_STATE_ERROR_WARNING; > > + } else { > > + priv->can.state = CAN_STATE_ERROR_ACTIVE; > > + } > > netif_device_attach(ndev); > > netif_start_queue(ndev); > > } > > @@ -1031,7 +1059,10 @@ static int __maybe_unused xcan_resume(struct > device *dev) > > return 0; > > } > > > > -static SIMPLE_DEV_PM_OPS(xcan_dev_pm_ops, xcan_suspend, > xcan_resume); > > +static const struct dev_pm_ops xcan_dev_pm_ops = { > > + SET_SYSTEM_SLEEP_PM_OPS(xcan_suspend, xcan_resume) > > + SET_RUNTIME_PM_OPS(xcan_runtime_suspend, xcan_runtime_resume, > NULL) > > +}; > > > > /** > > * xcan_probe - Platform registration call @@ -1072,7 +1103,7 @@ > > static int xcan_probe(struct platform_device *pdev) > > return -ENOMEM; > > > > priv = netdev_priv(ndev); > > - priv->dev = ndev; > > + priv->dev = &pdev->dev; > > priv->can.bittiming_const = &xcan_bittiming_const; > > priv->can.do_set_mode = xcan_do_set_mode; > > priv->can.do_get_berr_counter = xcan_get_berr_counter; @@ - > 1114,21 > > +1145,18 @@ static int xcan_probe(struct platform_device *pdev) > > } > > } > > > > - ret = clk_prepare_enable(priv->can_clk); > > - if (ret) { > > - dev_err(&pdev->dev, "unable to enable device clock\n"); > > - goto err_free; > > - } > > - > > - ret = clk_prepare_enable(priv->bus_clk); > > - if (ret) { > > - dev_err(&pdev->dev, "unable to enable bus clock\n"); > > - goto err_unprepare_disable_dev; > > - } > > - > > priv->write_reg = xcan_write_reg_le; > > priv->read_reg = xcan_read_reg_le; > > > > + pm_runtime_irq_safe(&pdev->dev); > > Have you tested the patch with lockdep enabled? Yes I tested with the lockdep enabled and it is working fine. clk_prepare_enable() can sleep > and pm_runtime_irq_safe() says that's it's ok to call the code from atomic > context. Either remove the pm_runtime_irq_safe() or only call the clk_enable(), > clk_disable in the RM runtime handlers. Ok removed the pm_runtime_irq_safe call and tested it is working fine. Will send the next version of the path. Regards, Kedar. > > > + pm_runtime_enable(&pdev->dev); > > + ret = pm_runtime_get_sync(&pdev->dev); > > + if (ret < 0) { > > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > > + __func__, ret); > > + goto err_pmdisable; > > + } > > + > > if (priv->read_reg(priv, XCAN_SR_OFFSET) != XCAN_SR_CONFIG_MASK) { > > priv->write_reg = xcan_write_reg_be; > > priv->read_reg = xcan_read_reg_be; > > @@ -1141,22 +1169,23 @@ static int xcan_probe(struct platform_device > *pdev) > > ret = register_candev(ndev); > > if (ret) { > > dev_err(&pdev->dev, "fail to register failed (err=%d)\n", ret); > > - goto err_unprepare_disable_busclk; > > + goto err_disableclks; > > } > > > > devm_can_led_init(ndev); > > - clk_disable_unprepare(priv->bus_clk); > > - clk_disable_unprepare(priv->can_clk); > > + > > + pm_runtime_put(&pdev->dev); > > + > > netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo > depth:%d\n", > > priv->reg_base, ndev->irq, priv->can.clock.freq, > > priv->tx_max); > > > > return 0; > > > > -err_unprepare_disable_busclk: > > - clk_disable_unprepare(priv->bus_clk); > > -err_unprepare_disable_dev: > > - clk_disable_unprepare(priv->can_clk); > > +err_disableclks: > > + pm_runtime_put(priv->dev); > > +err_pmdisable: > > + pm_runtime_disable(&pdev->dev); > > err_free: > > free_candev(ndev); > > err: > > @@ -1175,10 +1204,8 @@ static int xcan_remove(struct platform_device > *pdev) > > struct net_device *ndev = platform_get_drvdata(pdev); > > struct xcan_priv *priv = netdev_priv(ndev); > > > > - if (set_reset_mode(ndev) < 0) > > - netdev_err(ndev, "mode resetting failed!\n"); > > - > > unregister_candev(ndev); > > + pm_runtime_disable(&pdev->dev); > > netif_napi_del(&priv->napi); > > free_candev(ndev); > > > > > > Marc > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Industrial Linux Solutions | Phone: +49-231-2826-924 | > Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | > Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c index fc55e8e..fcb584f 100644 --- a/drivers/net/can/xilinx_can.c +++ b/drivers/net/can/xilinx_can.c @@ -32,6 +32,7 @@ #include <linux/can/dev.h> #include <linux/can/error.h> #include <linux/can/led.h> +#include <linux/pm_runtime.h> #define DRIVER_NAME "xilinx_can" @@ -138,7 +139,7 @@ struct xcan_priv { u32 (*read_reg)(const struct xcan_priv *priv, enum xcan_reg reg); void (*write_reg)(const struct xcan_priv *priv, enum xcan_reg reg, u32 val); - struct net_device *dev; + struct device *dev; void __iomem *reg_base; unsigned long irq_flags; struct clk *bus_clk; @@ -843,6 +844,13 @@ static int xcan_open(struct net_device *ndev) struct xcan_priv *priv = netdev_priv(ndev); int ret; + ret = pm_runtime_get_sync(priv->dev); + if (ret < 0) { + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", + __func__, ret); + return ret; + } + ret = request_irq(ndev->irq, xcan_interrupt, priv->irq_flags, ndev->name, ndev); if (ret < 0) { @@ -850,29 +858,17 @@ static int xcan_open(struct net_device *ndev) goto err; } - ret = clk_prepare_enable(priv->can_clk); - if (ret) { - netdev_err(ndev, "unable to enable device clock\n"); - goto err_irq; - } - - ret = clk_prepare_enable(priv->bus_clk); - if (ret) { - netdev_err(ndev, "unable to enable bus clock\n"); - goto err_can_clk; - } - /* Set chip into reset mode */ ret = set_reset_mode(ndev); if (ret < 0) { netdev_err(ndev, "mode resetting failed!\n"); - goto err_bus_clk; + goto err_irq; } /* Common open */ ret = open_candev(ndev); if (ret) - goto err_bus_clk; + goto err_irq; ret = xcan_chip_start(ndev); if (ret < 0) { @@ -888,13 +884,11 @@ static int xcan_open(struct net_device *ndev) err_candev: close_candev(ndev); -err_bus_clk: - clk_disable_unprepare(priv->bus_clk); -err_can_clk: - clk_disable_unprepare(priv->can_clk); err_irq: free_irq(ndev->irq, ndev); err: + pm_runtime_put(priv->dev); + return ret; } @@ -911,12 +905,11 @@ static int xcan_close(struct net_device *ndev) netif_stop_queue(ndev); napi_disable(&priv->napi); xcan_chip_stop(ndev); - clk_disable_unprepare(priv->bus_clk); - clk_disable_unprepare(priv->can_clk); free_irq(ndev->irq, ndev); close_candev(ndev); can_led_event(ndev, CAN_LED_EVENT_STOP); + pm_runtime_put(priv->dev); return 0; } @@ -935,27 +928,20 @@ static int xcan_get_berr_counter(const struct net_device *ndev, struct xcan_priv *priv = netdev_priv(ndev); int ret; - ret = clk_prepare_enable(priv->can_clk); - if (ret) - goto err; - - ret = clk_prepare_enable(priv->bus_clk); - if (ret) - goto err_clk; + ret = pm_runtime_get_sync(priv->dev); + if (ret < 0) { + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", + __func__, ret); + return ret; + } bec->txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK; bec->rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT); - clk_disable_unprepare(priv->bus_clk); - clk_disable_unprepare(priv->can_clk); + pm_runtime_put(priv->dev); return 0; - -err_clk: - clk_disable_unprepare(priv->can_clk); -err: - return ret; } @@ -968,15 +954,45 @@ static const struct net_device_ops xcan_netdev_ops = { /** * xcan_suspend - Suspend method for the driver - * @dev: Address of the platform_device structure + * @dev: Address of the device structure * * Put the driver into low power mode. - * Return: 0 always + * Return: 0 on success and failure value on error */ static int __maybe_unused xcan_suspend(struct device *dev) { - struct platform_device *pdev = dev_get_drvdata(dev); - struct net_device *ndev = platform_get_drvdata(pdev); + if (!device_may_wakeup(dev)) + return pm_runtime_force_suspend(dev); + + return 0; +} + +/** + * xcan_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 xcan_resume(struct device *dev) +{ + if (!device_may_wakeup(dev)) + return pm_runtime_force_resume(dev); + + return 0; + +} + +/** + * xcan_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 xcan_runtime_suspend(struct device *dev) +{ + struct net_device *ndev = dev_get_drvdata(dev); struct xcan_priv *priv = netdev_priv(ndev); if (netif_running(ndev)) { @@ -987,43 +1003,55 @@ static int __maybe_unused xcan_suspend(struct device *dev) priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK); priv->can.state = CAN_STATE_SLEEPING; - clk_disable(priv->bus_clk); - clk_disable(priv->can_clk); + clk_disable_unprepare(priv->bus_clk); + clk_disable_unprepare(priv->can_clk); return 0; } /** - * xcan_resume - Resume from suspend - * @dev: Address of the platformdevice structure + * xcan_runtime_resume - Runtime 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 xcan_resume(struct device *dev) +static int __maybe_unused xcan_runtime_resume(struct device *dev) { - struct platform_device *pdev = dev_get_drvdata(dev); - struct net_device *ndev = platform_get_drvdata(pdev); + struct net_device *ndev = dev_get_drvdata(dev); struct xcan_priv *priv = netdev_priv(ndev); int ret; + u32 isr, status; - ret = clk_enable(priv->bus_clk); + ret = clk_prepare_enable(priv->bus_clk); if (ret) { dev_err(dev, "Cannot enable clock.\n"); return ret; } - ret = clk_enable(priv->can_clk); + ret = clk_prepare_enable(priv->can_clk); if (ret) { dev_err(dev, "Cannot enable clock.\n"); clk_disable_unprepare(priv->bus_clk); return ret; } - priv->write_reg(priv, XCAN_MSR_OFFSET, 0); - priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_CEN_MASK); - priv->can.state = CAN_STATE_ERROR_ACTIVE; + priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK); + isr = priv->read_reg(priv, XCAN_ISR_OFFSET); + status = priv->read_reg(priv, XCAN_SR_OFFSET); if (netif_running(ndev)) { + if (isr & XCAN_IXR_BSOFF_MASK) { + priv->can.state = CAN_STATE_BUS_OFF; + priv->write_reg(priv, XCAN_SRR_OFFSET, + XCAN_SRR_RESET_MASK); + } else if ((status & XCAN_SR_ESTAT_MASK) == + XCAN_SR_ESTAT_MASK) { + priv->can.state = CAN_STATE_ERROR_PASSIVE; + } else if (status & XCAN_SR_ERRWRN_MASK) { + priv->can.state = CAN_STATE_ERROR_WARNING; + } else { + priv->can.state = CAN_STATE_ERROR_ACTIVE; + } netif_device_attach(ndev); netif_start_queue(ndev); } @@ -1031,7 +1059,10 @@ static int __maybe_unused xcan_resume(struct device *dev) return 0; } -static SIMPLE_DEV_PM_OPS(xcan_dev_pm_ops, xcan_suspend, xcan_resume); +static const struct dev_pm_ops xcan_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(xcan_suspend, xcan_resume) + SET_RUNTIME_PM_OPS(xcan_runtime_suspend, xcan_runtime_resume, NULL) +}; /** * xcan_probe - Platform registration call @@ -1072,7 +1103,7 @@ static int xcan_probe(struct platform_device *pdev) return -ENOMEM; priv = netdev_priv(ndev); - priv->dev = ndev; + priv->dev = &pdev->dev; priv->can.bittiming_const = &xcan_bittiming_const; priv->can.do_set_mode = xcan_do_set_mode; priv->can.do_get_berr_counter = xcan_get_berr_counter; @@ -1114,21 +1145,18 @@ static int xcan_probe(struct platform_device *pdev) } } - ret = clk_prepare_enable(priv->can_clk); - if (ret) { - dev_err(&pdev->dev, "unable to enable device clock\n"); - goto err_free; - } - - ret = clk_prepare_enable(priv->bus_clk); - if (ret) { - dev_err(&pdev->dev, "unable to enable bus clock\n"); - goto err_unprepare_disable_dev; - } - priv->write_reg = xcan_write_reg_le; priv->read_reg = xcan_read_reg_le; + pm_runtime_irq_safe(&pdev->dev); + pm_runtime_enable(&pdev->dev); + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) { + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", + __func__, ret); + goto err_pmdisable; + } + if (priv->read_reg(priv, XCAN_SR_OFFSET) != XCAN_SR_CONFIG_MASK) { priv->write_reg = xcan_write_reg_be; priv->read_reg = xcan_read_reg_be; @@ -1141,22 +1169,23 @@ static int xcan_probe(struct platform_device *pdev) ret = register_candev(ndev); if (ret) { dev_err(&pdev->dev, "fail to register failed (err=%d)\n", ret); - goto err_unprepare_disable_busclk; + goto err_disableclks; } devm_can_led_init(ndev); - clk_disable_unprepare(priv->bus_clk); - clk_disable_unprepare(priv->can_clk); + + pm_runtime_put(&pdev->dev); + netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo depth:%d\n", priv->reg_base, ndev->irq, priv->can.clock.freq, priv->tx_max); return 0; -err_unprepare_disable_busclk: - clk_disable_unprepare(priv->bus_clk); -err_unprepare_disable_dev: - clk_disable_unprepare(priv->can_clk); +err_disableclks: + pm_runtime_put(priv->dev); +err_pmdisable: + pm_runtime_disable(&pdev->dev); err_free: free_candev(ndev); err: @@ -1175,10 +1204,8 @@ static int xcan_remove(struct platform_device *pdev) struct net_device *ndev = platform_get_drvdata(pdev); struct xcan_priv *priv = netdev_priv(ndev); - if (set_reset_mode(ndev) < 0) - netdev_err(ndev, "mode resetting failed!\n"); - unregister_candev(ndev); + pm_runtime_disable(&pdev->dev); netif_napi_del(&priv->napi); free_candev(ndev);
Instead of enabling/disabling clocks at several locations in the driver, Use the runtime_pm framework. This consolidates the actions for runtime PM In the appropriate callbacks and makes the driver more readable and mantainable. Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com> --- Changes for v7: - Removed the unnecessary clk_prepare/clk_unprepare calls From the probe and remove as suggested by Soren. Changes for v6: - Updated the driver with review comments as suggested by Marc. Changes for v5: - Updated with the review comments. Updated the remove fuction to use runtime_pm. Chnages for v4: - Updated with the review comments. Changes for v3: - Converted the driver to use runtime_pm. Changes for v2: - Removed the struct platform_device* from suspend/resume as suggest by Lothar. drivers/net/can/xilinx_can.c | 177 +++++++++++++++++++++++++------------------ 1 file changed, 102 insertions(+), 75 deletions(-)