Re: [PATCH v5 2/2] phy: rockchip-inno-usb2: add a new driver for Rockchip usb2phy

[Guenter Roeck <groeck@google.com>]

On Tue, Jun 14, 2016 at 6:14 PM, Frank Wang <frank.wang@rock-chips.com> wrote:
> Hi Heiko & Guenter,
>
>
> On 2016/6/14 22:00, Heiko Stübner wrote:
>>
>> Am Dienstag, 14. Juni 2016, 06:50:31 schrieb Guenter Roeck:
>>>
>>> On Tue, Jun 14, 2016 at 6:27 AM, Heiko Stübner <heiko@sntech.de> wrote:
>>>>
>>>> Am Montag, 13. Juni 2016, 10:10:10 schrieb Frank Wang:
>>>>>
>>>>> The newer SoCs (rk3366, rk3399) take a different usb-phy IP block
>>>>> than rk3288 and before, and most of phy-related registers are also
>>>>> different from the past, so a new phy driver is required necessarily.
>>>>>
>>>>> Signed-off-by: Frank Wang <frank.wang@rock-chips.com>
>>>>> ---
>>
>> [...]
>>
>>>>> +static int rockchip_usb2phy_init(struct phy *phy)
>>>>> +{
>>>>> +     struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy);
>>>>> +     struct rockchip_usb2phy *rphy = dev_get_drvdata(phy->dev.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 driver.
>
>
> 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(struct
> rockchip_usb2phy *rphy,
>  {
>         int ret;
>
> -       rport->port_id = USB2PHY_PORT_HOST;
>         rport->port_cfg = &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.

Guenter

>
> +       rport->port_id = USB2PHY_PORT_HOST;
>
>> Or from what I've seen, handling it as similar to the host-port should
>> work
>> initially as well most likely, supplying the additional otg-parts later
>> on.
>
>
> @Guenter, just as Heiko said, the otg-parts is not ready now, it will be
> supplied later.
>
>
> BR.
> Frank
>