Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <a7b83352-b024-3431-7c85-f150255cf76e@linaro.org>
Date:   Mon, 5 Dec 2022 09:02:06 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.5.1
Subject: Re: [RFC PATCH v1 1/2] dt-bindings: usb: samsung,exynos-xhci: support
 Samsung Exynos xHCI Controller
Content-Language: en-US
To:     Jung Daehwan <dh10.jung@samsung.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        Mathias Nyman <mathias.nyman@intel.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Linus Walleij <linus.walleij@linaro.org>,
        Colin Ian King <colin.i.king@gmail.com>,
        Artur Bujdoso <artur.bujdoso@gmail.com>,
        Juergen Gross <jgross@suse.com>,
        Tomer Maimon <tmaimon77@gmail.com>,
        "open list:USB SUBSYSTEM" <linux-usb@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        "moderated list:ARM/SAMSUNG S3C, S5P AND EXYNOS ARM ARCHITECTURES" 
        <linux-arm-kernel@lists.infradead.org>,
        "open list:ARM/SAMSUNG S3C, S5P AND EXYNOS ARM ARCHITECTURES" 
        <linux-samsung-soc@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>, sc.suh@samsung.com,
        taehyun.cho@samsung.com, jh0801.jung@samsung.com,
        eomji.oh@samsung.com
References: <1669860811-171746-1-git-send-email-dh10.jung@samsung.com>
 <CGME20221201021941epcas2p4a536a9eb029a990fcb9f27f2b4668d07@epcas2p4.samsung.com>
 <1669860811-171746-2-git-send-email-dh10.jung@samsung.com>
 <e140fdfd-4d8b-7214-d264-0503e6fcc498@linaro.org>
 <20221205020634.GA54922@ubuntu>
 <380178d3-7248-4200-d9db-2fd8584eb386@linaro.org>
 <20221205074804.GF54922@ubuntu>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20221205074804.GF54922@ubuntu>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 05/12/2022 08:48, Jung Daehwan wrote:
> On Mon, Dec 05, 2022 at 08:31:46AM +0100, Krzysztof Kozlowski wrote:
>> On 05/12/2022 03:06, Jung Daehwan wrote:
>>> On Thu, Dec 01, 2022 at 09:59:06AM +0100, Krzysztof Kozlowski wrote:
>>>> On 01/12/2022 03:13, Daehwan Jung wrote:
>>>>> Add the Samsung Exynos xHCI Controller bindings with DT schema format.
>>>>>
>>>>> Signed-off-by: Daehwan Jung <dh10.jung@samsung.com>
>>>>> ---
>>>>>  .../bindings/usb/samsung,exynos-xhci.yaml     | 25 +++++++++++++++++++
>>>>>  1 file changed, 25 insertions(+)
>>>>>  create mode 100644 Documentation/devicetree/bindings/usb/samsung,exynos-xhci.yaml
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/usb/samsung,exynos-xhci.yaml b/Documentation/devicetree/bindings/usb/samsung,exynos-xhci.yaml
>>>>> new file mode 100644
>>>>> index 000000000000..c5dde53b6491
>>>>> --- /dev/null
>>>>> +++ b/Documentation/devicetree/bindings/usb/samsung,exynos-xhci.yaml
>>>>> @@ -0,0 +1,25 @@
>>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>>>> +%YAML 1.2
>>>>> +---
>>>>> +$id: https://protect2.fireeye.com/v1/url?k=7899b46f-19e45c17-78983f20-74fe485fffb1-728a1b33a5d009dd&q=1&e=bdc50247-e986-43da-a15e-03ac6c3a25e8&u=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fusb%2Fsamsung%2Cexynos-xhci.yaml%23
>>>>> +$schema: https://protect2.fireeye.com/v1/url?k=ea1282f0-8b6f6a88-ea1309bf-74fe485fffb1-536f21757c62f28b&q=1&e=bdc50247-e986-43da-a15e-03ac6c3a25e8&u=http%3A%2F%2Fdevicetree.org%2Fmeta-schemas%2Fcore.yaml%23
>>>>> +
>>>>> +title: Samsung Exynos xHCI
>>>>> +
>>>>> +maintainers:
>>>>> +  - Daehwan Jung <dh10.jung@samsung.com>
>>>>> +
>>>>> +properties:
>>>>> +  compatible:
>>>>> +    const: samsung,exynos-xhci
>>>>> +
>>>>> +required:
>>>>> +  - compatible
>>>>> +
>>>>> +additionalProperties: false
>>>>> +
>>>>
>>>> These do not look like complete bindings... What type of device has no
>>>> resources at all, just compatible?
>>>>
>>>> Best regards,
>>>> Krzysztof
>>>>
>>>>
>>>
>>> It gets resources from dwc->xhci_resources as you can see
>>> dwc3_host_init(usb/dwc3/host.c). I think it doesn't need to get another resource.
>>
>> You refer to driver, but we talk about hardware. Not driver. Your
>> hardware has no resources, so this does not look like complete binding.
>>
>> Best regards,
>> Krzysztof
>>
>>
> 
> It actually doesn't get new resources but shares resources of dwc3 driver.
> You mean it's not complete binding without resources? Is it okay if I
> add description about it? If not, could you suggest a good way?

No, description is not okay, because I doubt that your device does not
have IO space, clocks, interrupts and phys.

Therefore description changes nothing - binding still does not describe
the hardware. How to proceed? Write binding for a real hardware, not
wakelock-Android-driver-override.

Best regards,
Krzysztof