From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [PATCH v5 2/2] phy: rockchip-inno-usb2: add a new driver for Rockchip usb2phy Date: Thu, 16 Jun 2016 06:12:14 -0700 Message-ID: <5762A5AE.5030400@roeck-us.net> References: <1465783810-18756-1-git-send-email-frank.wang@rock-chips.com> <7225720.0AClDW7eQ6@diego> <4065185.1IWsBDlcMJ@diego> <24acf224-e792-6648-fcdb-8729ded6df84@rock-chips.com> <328485b0-2c5d-5d5e-a21b-6a26e487a923@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <328485b0-2c5d-5d5e-a21b-6a26e487a923@rock-chips.com> Sender: linux-kernel-owner@vger.kernel.org To: Frank Wang , Guenter Roeck Cc: =?UTF-8?Q?Heiko_St=c3=bcbner?= , Douglas Anderson , Guenter Roeck , jwerner@chromium.org, kishon@ti.com, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, Kumar Gala , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-usb@vger.kernel.org, linux-rockchip@lists.infradead.org, Ziyuan Xu , Kever Yang , Tao Huang , william.wu@rock-chips.com List-Id: devicetree@vger.kernel.org On 06/15/2016 06:47 PM, Frank Wang wrote: > Hi Guenter & Heiko, > > On 2016/6/15 23:47, Guenter Roeck wrote: >> On Tue, Jun 14, 2016 at 6:14 PM, Frank Wang wrote: >>> Hi Heiko & Guenter, >>> >>> >>> On 2016/6/14 22:00, Heiko St=C3=BCbner wrote: >>>> Am Dienstag, 14. Juni 2016, 06:50:31 schrieb Guenter Roeck: >>>>> On Tue, Jun 14, 2016 at 6:27 AM, Heiko St=C3=BCbner wrote: >>>>>> Am Montag, 13. Juni 2016, 10:10:10 schrieb Frank Wang: >>>>>>> The newer SoCs (rk3366, rk3399) take a different usb-phy IP blo= ck >>>>>>> than rk3288 and before, and most of phy-related registers are a= lso >>>>>>> different from the past, so a new phy driver is required necess= arily. >>>>>>> >>>>>>> Signed-off-by: Frank Wang >>>>>>> --- >>>> [...] >>>> >>>>>>> +static int rockchip_usb2phy_init(struct phy *phy) >>>>>>> +{ >>>>>>> + struct rockchip_usb2phy_port *rport =3D phy_get_drvdata(p= hy); >>>>>>> + struct rockchip_usb2phy *rphy =3D dev_get_drvdata(phy->de= v.parent); >>>>>>> + int ret; >>>>>>> + >>>>>>> >>>>>> if (!rport->port_cfg) >>>>>> return 0; >>>>>> >>>>>> Otherwise the currently empty otg-port will cause null-pointer >>>>>> dereferences >>>>>> when it gets assigned in the devicetree already. >>>>> Not really, at least not here - that port should not have port_id= set >>>>> to USB2PHY_PORT_HOST. >>>>> >>>>> Does it even make sense to instantiate the otg port ? Is it going= to >>>>> do anything without port configuration ? >>>> Ok, that would be the other option - not creating the phy in the d= river. >>> >>> Well, I will put this conditional inside *_host_port_init(), if it = is an >>> empty, the phy-device should not be created. >>> Something like the following: >>> >>> --- a/drivers/phy/phy-rockchip-inno-usb2.c >>> +++ b/drivers/phy/phy-rockchip-inno-usb2.c >>> @@ -483,9 +483,13 @@ static int rockchip_usb2phy_host_port_init(str= uct >>> rockchip_usb2phy *rphy, >>> { >>> int ret; >>> >>> - rport->port_id =3D USB2PHY_PORT_HOST; >>> rport->port_cfg =3D &rphy->phy_cfg->port_cfgs[USB2PHY_PORT= _HOST]; >>> + if (!rport->port_cfg) { >>> + dev_err(rphy->dev, "no host port-config provided.\n= "); >>> + return -EINVAL; >>> + } >> This would never be NULL. At issue is that you don't assign port_cfg >> if the port is _not_ a host port. > > Sorry, I made a mistake. How about something like the following: > Yes, that should work. Just keep in mind that there could always be a port named "something-port", so you'll always need some kind of check (and possibly return an error if a port with a wrong name is provided). Thanks, Guenter > @@ -574,6 +579,15 @@ static int rockchip_usb2phy_probe(struct platfor= m_device *pdev) > struct rockchip_usb2phy_port *rport =3D &rphy->ports= [index]; > struct phy *phy; > > + /* > + * This driver aim to support both otg-port and host-= port, > + * but unfortunately, the otg part is not ready in cu= rrent, > + * so this comments and below codes are interim, whic= h should > + * be removed after otg-port is supplied soon. > + */ > + if (of_node_cmp(child_np->name, "host-port")) > + goto next_child; > + > phy =3D devm_phy_create(dev, child_np, &rockchip_usb= 2phy_ops); > if (IS_ERR(phy)) { > dev_err(dev, "failed to create phy\n"); > @@ -582,17 +596,13 @@ static int rockchip_usb2phy_probe(struct platfo= rm_device *pdev) > } > > rport->phy =3D phy; > - > - /* initialize otg/host port separately */ > - if (!of_node_cmp(child_np->name, "host-port")) { > - ret =3D rockchip_usb2phy_host_port_init(rphy,= rport, > - child_np); > - if (ret) > - goto put_child; > - } > - > phy_set_drvdata(rport->phy, rport); > > + ret =3D rockchip_usb2phy_host_port_init(rphy, rport, = child_np); > + if (ret) > + goto put_child; > + > +next_child: > /* to prevent out of boundary */ > if (++index >=3D rphy->phy_cfg->num_ports) > break; > > > BR. > Frank > >