From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752307AbbJYUYV (ORCPT ); Sun, 25 Oct 2015 16:24:21 -0400 Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:39816 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751600AbbJYUYT (ORCPT ); Sun, 25 Oct 2015 16:24:19 -0400 Subject: Re: [PATCH v7] can: xilinx: Convert to runtime_pm To: Kedareswara rao Appana , anirudh@xilinx.com, wg@grandegger.com, michal.simek@xilinx.com, soren.brinkmann@xilinx.com References: <1445577818-26165-1-git-send-email-appanad@xilinx.com> Cc: linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Kedareswara rao Appana From: Marc Kleine-Budde X-Enigmail-Draft-Status: N1110 Message-ID: <562D3A5C.9020901@pengutronix.de> Date: Sun, 25 Oct 2015 21:23:56 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.3.0 MIME-Version: 1.0 In-Reply-To: <1445577818-26165-1-git-send-email-appanad@xilinx.com> Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="e6LuNV2iI7hSErhKiDjpXRLACLodhpsFT" X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --e6LuNV2iI7hSErhKiDjpXRLACLodhpsFT Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable 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 man= tainable. >=20 > Signed-off-by: Kedareswara rao Appana > --- > 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. >=20 > drivers/net/can/xilinx_can.c | 177 +++++++++++++++++++++++++----------= -------- > 1 file changed, 102 insertions(+), 75 deletions(-) >=20 > 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 > #include > #include > +#include > =20 > #define DRIVER_NAME "xilinx_can" > =20 > @@ -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 =3D netdev_priv(ndev); > int ret; > =20 > + ret =3D pm_runtime_get_sync(priv->dev); > + if (ret < 0) { > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > + __func__, ret); > + return ret; > + } > + > ret =3D 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; > } > =20 > - ret =3D clk_prepare_enable(priv->can_clk); > - if (ret) { > - netdev_err(ndev, "unable to enable device clock\n"); > - goto err_irq; > - } > - > - ret =3D 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 =3D set_reset_mode(ndev); > if (ret < 0) { > netdev_err(ndev, "mode resetting failed!\n"); > - goto err_bus_clk; > + goto err_irq; > } > =20 > /* Common open */ > ret =3D open_candev(ndev); > if (ret) > - goto err_bus_clk; > + goto err_irq; > =20 > ret =3D xcan_chip_start(ndev); > if (ret < 0) { > @@ -888,13 +884,11 @@ static int xcan_open(struct net_device *ndev) > =20 > 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; > } > =20 > @@ -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); > =20 > can_led_event(ndev, CAN_LED_EVENT_STOP); > + pm_runtime_put(priv->dev); > =20 > return 0; > } > @@ -935,27 +928,20 @@ static int xcan_get_berr_counter(const struct net= _device *ndev, > struct xcan_priv *priv =3D netdev_priv(ndev); > int ret; > =20 > - ret =3D clk_prepare_enable(priv->can_clk); > - if (ret) > - goto err; > - > - ret =3D clk_prepare_enable(priv->bus_clk); > - if (ret) > - goto err_clk; > + ret =3D pm_runtime_get_sync(priv->dev); > + if (ret < 0) { > + netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", > + __func__, ret); > + return ret; > + } > =20 > bec->txerr =3D priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_M= ASK; > bec->rxerr =3D ((priv->read_reg(priv, XCAN_ECR_OFFSET) & > XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT); > =20 > - clk_disable_unprepare(priv->bus_clk); > - clk_disable_unprepare(priv->can_clk); > + pm_runtime_put(priv->dev); > =20 > return 0; > - > -err_clk: > - clk_disable_unprepare(priv->can_clk); > -err: > - return ret; > } > =20 > =20 > @@ -968,15 +954,45 @@ static const struct net_device_ops xcan_netdev_op= s =3D { > =20 > /** > * 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 =3D dev_get_drvdata(dev); > - struct net_device *ndev =3D 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 =3D dev_get_drvdata(dev); > struct xcan_priv *priv =3D netdev_priv(ndev); > =20 > if (netif_running(ndev)) { > @@ -987,43 +1003,55 @@ static int __maybe_unused xcan_suspend(struct de= vice *dev) > priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK); > priv->can.state =3D CAN_STATE_SLEEPING; > =20 > - clk_disable(priv->bus_clk); > - clk_disable(priv->can_clk); > + clk_disable_unprepare(priv->bus_clk); > + clk_disable_unprepare(priv->can_clk); > =20 > return 0; > } > =20 > /** > - * 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 =3D dev_get_drvdata(dev); > - struct net_device *ndev =3D platform_get_drvdata(pdev); > + struct net_device *ndev =3D dev_get_drvdata(dev); > struct xcan_priv *priv =3D netdev_priv(ndev); > int ret; > + u32 isr, status; > =20 > - ret =3D clk_enable(priv->bus_clk); > + ret =3D clk_prepare_enable(priv->bus_clk); > if (ret) { > dev_err(dev, "Cannot enable clock.\n"); > return ret; > } > - ret =3D clk_enable(priv->can_clk); > + ret =3D clk_prepare_enable(priv->can_clk); > if (ret) { > dev_err(dev, "Cannot enable clock.\n"); > clk_disable_unprepare(priv->bus_clk); > return ret; > } > =20 > - priv->write_reg(priv, XCAN_MSR_OFFSET, 0); > - priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_CEN_MASK); > - priv->can.state =3D CAN_STATE_ERROR_ACTIVE; > + priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK); > + isr =3D priv->read_reg(priv, XCAN_ISR_OFFSET); > + status =3D priv->read_reg(priv, XCAN_SR_OFFSET); > =20 > if (netif_running(ndev)) { > + if (isr & XCAN_IXR_BSOFF_MASK) { > + priv->can.state =3D CAN_STATE_BUS_OFF; > + priv->write_reg(priv, XCAN_SRR_OFFSET, > + XCAN_SRR_RESET_MASK); > + } else if ((status & XCAN_SR_ESTAT_MASK) =3D=3D > + XCAN_SR_ESTAT_MASK) { > + priv->can.state =3D CAN_STATE_ERROR_PASSIVE; > + } else if (status & XCAN_SR_ERRWRN_MASK) { > + priv->can.state =3D CAN_STATE_ERROR_WARNING; > + } else { > + priv->can.state =3D CAN_STATE_ERROR_ACTIVE; > + } > netif_device_attach(ndev); > netif_start_queue(ndev); > } > @@ -1031,7 +1059,10 @@ static int __maybe_unused xcan_resume(struct dev= ice *dev) > return 0; > } > =20 > -static SIMPLE_DEV_PM_OPS(xcan_dev_pm_ops, xcan_suspend, xcan_resume); > +static const struct dev_pm_ops xcan_dev_pm_ops =3D { > + SET_SYSTEM_SLEEP_PM_OPS(xcan_suspend, xcan_resume) > + SET_RUNTIME_PM_OPS(xcan_runtime_suspend, xcan_runtime_resume, NULL) > +}; > =20 > /** > * xcan_probe - Platform registration call > @@ -1072,7 +1103,7 @@ static int xcan_probe(struct platform_device *pde= v) > return -ENOMEM; > =20 > priv =3D netdev_priv(ndev); > - priv->dev =3D ndev; > + priv->dev =3D &pdev->dev; > priv->can.bittiming_const =3D &xcan_bittiming_const; > priv->can.do_set_mode =3D xcan_do_set_mode; > priv->can.do_get_berr_counter =3D xcan_get_berr_counter; > @@ -1114,21 +1145,18 @@ static int xcan_probe(struct platform_device *p= dev) > } > } > =20 > - ret =3D clk_prepare_enable(priv->can_clk); > - if (ret) { > - dev_err(&pdev->dev, "unable to enable device clock\n"); > - goto err_free; > - } > - > - ret =3D 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 =3D xcan_write_reg_le; > priv->read_reg =3D xcan_read_reg_le; > =20 > + 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 =3D 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) !=3D XCAN_SR_CONFIG_MASK) { > priv->write_reg =3D xcan_write_reg_be; > priv->read_reg =3D xcan_read_reg_be; > @@ -1141,22 +1169,23 @@ static int xcan_probe(struct platform_device *p= dev) > ret =3D register_candev(ndev); > if (ret) { > dev_err(&pdev->dev, "fail to register failed (err=3D%d)\n", ret); > - goto err_unprepare_disable_busclk; > + goto err_disableclks; > } > =20 > 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=3D0x%p irq=3D%d clock=3D%d, tx fifo depth:= %d\n", > priv->reg_base, ndev->irq, priv->can.clock.freq, > priv->tx_max); > =20 > return 0; > =20 > -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 *p= dev) > struct net_device *ndev =3D platform_get_drvdata(pdev); > struct xcan_priv *priv =3D netdev_priv(ndev); > =20 > - 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); > =20 >=20 Marc --=20 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 | --e6LuNV2iI7hSErhKiDjpXRLACLodhpsFT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBCgAGBQJWLTpcAAoJEP5prqPJtc/HD3sIAJRzsFD2EOicfb38eBbuDiCx acPC7jJ3+pZuQhuKPBR6hPlAiSayvjFiMJyXRlrj6pHxrI8NGEWc3hGknvB7LAMU EOGlDuHWl+3fg9mPMNo5S40mOfsXvgOyfSm8MO4bLxxmrWWsaaRGgUCngc8OYn1b S3axMk3yKVqZ8MwwlunU+pTJ6FuLGLivwaQH4JRkBZw99egxjq3d98Z/ayp59E9E C1jkIk8Ts69KVgDxh12JCK8L8dCBde/aJVaXTqXyqKcTT6bc3yVQwLjmgsG9f/gf hYTWy/4GzZRA+lCygJsnCiTBY37O777tHlnLFu2EZzNqYKdxRZWXjd4fCFV8XTM= =FBjs -----END PGP SIGNATURE----- --e6LuNV2iI7hSErhKiDjpXRLACLodhpsFT--