From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Kleine-Budde Subject: Re: [PATCH v5] can: c_can: Add runtime PM support to Bosch C_CAN/D_CAN controller Date: Tue, 07 Aug 2012 13:57:05 +0200 Message-ID: <50210291.6020307@pengutronix.de> References: <1344338457-595-1-git-send-email-anilkumar@ti.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig4F7E1AC2F146BEF91ECCC057" Return-path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:58009 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753962Ab2HGL5R (ORCPT ); Tue, 7 Aug 2012 07:57:17 -0400 In-Reply-To: <1344338457-595-1-git-send-email-anilkumar@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: AnilKumar Ch Cc: wg@grandegger.com, linux-can@vger.kernel.org, linux-omap@vger.kernel.org, anantgole@ti.com, nsekhar@ti.com This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig4F7E1AC2F146BEF91ECCC057 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 08/07/2012 01:20 PM, AnilKumar Ch wrote: > Add Runtime PM support to C_CAN/D_CAN controller. The runtime PM > APIs control clocks for C_CAN/D_CAN IP and prevent access to the > register of C_CAN/D_CAN IP when clock is turned off. >=20 > Signed-off-by: AnilKumar Ch > --- > This patch has been tested on AM335X EVM. Due to lack of hardware > I am not able to test c_can functionality. I appreciate if anyone > can test c_can functionality with this patch. The "priv->pdev->dev" will not work for c_can/d_can which are not using the platform driver. Options: a) priv->dev add a struct device pointer to the priv, and 1) guard pm_runtime_get_sync() for priv->dev =3D=3D NULL (or check if pm_runtime_get_sync copes with NULL pointer) - or - 2) fill in the priv->dev in all other drivers (i.e. PCI) and check if it makes sense/works to call it on PCI hardware b) convert all other drivers, i.e. the PCI driver to create a platform device Without thinking long, I suggest to a) with flavour 1) Maybe there are better solutions. Marc More comments inline: >=20 > This patch is based on "can-next/master"=20 >=20 > Changes from v4: > - Incorporated Vaibhav H review comments on v4. > * Moved pm_runtime put/get_sync calls to appropriate positions. > - This patch is from "Add DT support to C_CAN/D_CAN controller" > patch series. Rest of the patches in this series were applied > so this v5 contains only this patch. >=20 > drivers/net/can/c_can/c_can.c | 8 ++++++++ > drivers/net/can/c_can/c_can.h | 1 + > drivers/net/can/c_can/c_can_platform.c | 11 +++++++++++ > 3 files changed, 20 insertions(+) >=20 > diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_ca= n.c > index eea6608..ca1151d 100644 > --- a/drivers/net/can/c_can/c_can.c > +++ b/drivers/net/can/c_can/c_can.c > @@ -34,6 +34,8 @@ > #include > #include > #include > +#include > +#include > =20 > #include > #include > @@ -673,6 +675,8 @@ static int c_can_get_berr_counter(const struct net_= device *dev, > unsigned int reg_err_counter; > struct c_can_priv *priv =3D netdev_priv(dev); > =20 > + pm_runtime_get_sync(&priv->pdev->dev); > + Why do you make a get_sync() here, where's the correspondning put_sync()?= > reg_err_counter =3D priv->read_reg(priv, C_CAN_ERR_CNT_REG); > bec->rxerr =3D (reg_err_counter & ERR_CNT_REC_MASK) >> > ERR_CNT_REC_SHIFT; > @@ -1053,6 +1057,8 @@ static int c_can_open(struct net_device *dev) > int err; > struct c_can_priv *priv =3D netdev_priv(dev); > =20 > + pm_runtime_get_sync(&priv->pdev->dev); > + > /* open the can device */ > err =3D open_candev(dev); > if (err) { What if open_candev() fails? Please add a jump label exit_open_candev_fail and add thje put_sync() there. goto exit_open_candev_fail; > @@ -1079,6 +1085,7 @@ static int c_can_open(struct net_device *dev) > =20 > exit_irq_fail: > close_candev(dev); exit_open_candev_fail: > + pm_runtime_put_sync(&priv->pdev->dev); > return err; > } > =20 > @@ -1091,6 +1098,7 @@ static int c_can_close(struct net_device *dev) > c_can_stop(dev); > free_irq(dev->irq, dev); > close_candev(dev); > + pm_runtime_put_sync(&priv->pdev->dev); > =20 > return 0; > } > diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_ca= n.h > index 4e56baa..ef84439 100644 > --- a/drivers/net/can/c_can/c_can.h > +++ b/drivers/net/can/c_can/c_can.h > @@ -153,6 +153,7 @@ struct c_can_priv { > struct can_priv can; /* must be the first member */ > struct napi_struct napi; > struct net_device *dev; > + struct platform_device *pdev; > int tx_object; > int current_status; > int last_status; > diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c= _can/c_can_platform.c > index d0a66cf..cbb1184 100644 > --- a/drivers/net/can/c_can/c_can_platform.c > +++ b/drivers/net/can/c_can/c_can_platform.c > @@ -32,6 +32,7 @@ > #include > #include > #include > +#include > =20 > #include > =20 > @@ -177,7 +178,11 @@ static int __devinit c_can_plat_probe(struct platf= orm_device *pdev) > goto exit_free_device; > } > =20 > + pm_runtime_enable(&pdev->dev); > + pm_runtime_get_sync(&pdev->dev); > + > dev->irq =3D irq; > + priv->pdev =3D pdev; > priv->base =3D addr; > priv->can.clock.freq =3D clk_get_rate(clk); > priv->priv =3D clk; > @@ -192,12 +197,16 @@ static int __devinit c_can_plat_probe(struct plat= form_device *pdev) > goto exit_free_device; > } > =20 > + pm_runtime_put_sync(&pdev->dev); > + > dev_info(&pdev->dev, "%s device registered (regs=3D%p, irq=3D%d)\n", > KBUILD_MODNAME, priv->base, dev->irq); > return 0; > =20 > exit_free_device: > platform_set_drvdata(pdev, NULL); > + pm_runtime_put_sync(&pdev->dev); > + pm_runtime_disable(&pdev->dev); > free_c_can_dev(dev); > exit_iounmap: > iounmap(addr); > @@ -226,6 +235,8 @@ static int __devexit c_can_plat_remove(struct platf= orm_device *pdev) > mem =3D platform_get_resource(pdev, IORESOURCE_MEM, 0); > release_mem_region(mem->start, resource_size(mem)); > =20 > + pm_runtime_put_sync(&pdev->dev); > + pm_runtime_disable(&pdev->dev); > clk_put(priv->priv); > =20 > return 0; >=20 --=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 | --------------enig4F7E1AC2F146BEF91ECCC057 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAlAhApUACgkQjTAFq1RaXHMlqwCbB4cuwReh654CfAwoq/TPcUYv A4gAoIwvuiSuhf4133Jk+WtMq+T4OqCM =lD9k -----END PGP SIGNATURE----- --------------enig4F7E1AC2F146BEF91ECCC057--