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References: <20190302090505.65542-1-chenyu56@huawei.com> <20190302090505.65542-11-chenyu56@huawei.com>
In-Reply-To: <20190302090505.65542-11-chenyu56@huawei.com>
From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Sat, 2 Mar 2019 18:01:29 +0200
Message-ID: <CAHp75VdaNn4OQAQt1cU8CZ+Cton90kxmwQSG5Du7KUzPR3hSCg@mail.gmail.com>
Subject: Re: [PATCH v3 10/12] hikey960: Support usb functionality of Hikey960
To:     Yu Chen <chenyu56@huawei.com>
Cc:     USB <linux-usb@vger.kernel.org>,
        devicetree <devicetree@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        John Stultz <john.stultz@linaro.org>,
        Suzhuangluan <suzhuangluan@hisilicon.com>,
        Kongfei <kongfei@hisilicon.com>, liuyu712@hisilicon.com,
        wanghu17@hisilicon.com, butao@hisilicon.com,
        Yao Chen <chenyao11@huawei.com>, fangshengzhou@hisilicon.com,
        lipengcheng8@huawei.com, songxiaowei <songxiaowei@hisilicon.com>,
        xu yiping <xuyiping@hisilicon.com>, xuyoujun4@huawei.com,
        yudongbin@hisilicon.com, zangleigang@hisilicon.com,
        Chunfeng Yun <chunfeng.yun@mediatek.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Binghui Wang <wangbinghui@hisilicon.com>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>
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On Sat, Mar 2, 2019 at 11:05 AM Yu Chen <chenyu56@huawei.com> wrote:
>
> This driver handles usb hub power on and typeC port event of HiKey960 board:
> 1)DP&DM switching between usb hub and typeC port base on typeC port
> state
> 2)Control power of usb hub on Hikey960
> 3)Control vbus of typeC port

> +config HISI_HIKEY_USB
> +       tristate "USB functionality of HiSilicon Hikey Platform"
> +       depends on OF && GPIOLIB
> +       help
> +         If you say yes here you get support for usb functionality of HiSilicon Hikey Platform.

> +#include <linux/of.h>

It's hard to see why this have
depends on OF followed by above header inclusion.

> +       hisi_hikey_usb->typec_vbus = devm_gpiod_get(dev, "typec-vbus",
> +                       GPIOD_OUT_LOW);

> +       if (!hisi_hikey_usb->typec_vbus)
> +               return -ENOENT;

Hmm... Is it possible to get NULL pointer from gpiod_get() at all?

> +       if (!hisi_hikey_usb->otg_switch)
> +               return -ENOENT;

Ditto.

> +       /* hub-vdd33-en is optional */
> +       hisi_hikey_usb->hub_vbus = devm_gpiod_get(dev, "hub-vdd33-en",
> +                       GPIOD_OUT_HIGH);

devm_gpio_get_optional() if it's indeed optional.

> +       hisi_hikey_usb->role_sw = usb_role_switch_get(dev);
> +       if (!hisi_hikey_usb->role_sw)
> +               return -EPROBE_DEFER;

> +       else if (IS_ERR(hisi_hikey_usb->role_sw))

Redundant 'else'

> +               return PTR_ERR(hisi_hikey_usb->role_sw);

> +static const struct of_device_id id_table_hisi_hikey_usb[] = {
> +       {.compatible = "hisilicon,gpio_hubv1"},
> +       {.compatible = "hisilicon,hikey960_usb"},
> +       {}
> +};

MODULE_DEVICE_TABLE()?

-- 
With Best Regards,
Andy Shevchenko