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Message-ID: <45d25fd5-465f-347b-448b-ce171626f34e@linaro.org>
Date:   Sat, 5 Aug 2023 23:30:21 +0200
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Subject: Re: [PATCH v3 3/9] arm64: dts: amlogic: Used onboard usb hub reset on
 odroid c2
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To:     Ben Wolsieffer <benwolsieffer@gmail.com>,
        Anand Moon <linux.amoon@gmail.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Kevin Hilman <khilman@baylibre.com>,
        Jerome Brunet <jbrunet@baylibre.com>,
        Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
        linux-amlogic@lists.infradead.org,
        Matthias Kaehlcke <mka@chromium.org>,
        Alexander Stein <alexander.stein@ew.tq-group.com>,
        Johan Hovold <johan@kernel.org>, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20230121175639.12818-1-linux.amoon@gmail.com>
 <20230121175639.12818-4-linux.amoon@gmail.com>
 <ZMrFb7H1ynwwBSCA@Dell-Inspiron-15>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <ZMrFb7H1ynwwBSCA@Dell-Inspiron-15>
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Precedence: bulk

On 02/08/2023 23:06, Ben Wolsieffer wrote:
> On Sat, Jan 21, 2023 at 05:56:31PM +0000, Anand Moon wrote:
>> On Odroid c2 previously use gpio-hog to reset the usb hub,
>> switch to used on-board usb hub reset to enable the usb hub
>> and enable power to hub.
>>

...

>> +	hub@1 {
>> +		/* Genesys Logic GL852G USB 2.0 hub */
>> +		compatible = "usb5e3,610";
>> +		reg = <1>;
>> +		vdd-supply = <&p5v0>;
>> +		reset-gpio = <&gpio_ao GPIOAO_4 GPIO_ACTIVE_LOW>;
>> +	};
>>  };
>> -- 
>> 2.38.1
>>
> 
> Hello,
> 
> This patch breaks USB support on the ODROID-C2. As soon as the
> onboard_usb_hub module is loaded, all USB devices disconnect.
> Blacklisting onboard_usb_hub makes USB work as expected.
> 
> I tried to reproduce the problem by manually toggling the reset line,
> but the problem seems to be specific to this driver. When reset is
> asserted manually, the devices disconnect, but they all enumerate again
> as soon as reset is released.
> 
> Also, I have been unable to make USB work again (until the next reboot)
> even after unloading onboard_usb_hub.

Wasn't this patch made exactly to fix USB support, not break it? I might
be missing something but maybe this was not tested at all?

Best regards,
Krzysztof