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Message-ID: <158cf11e-53fa-4af8-a8a5-db18d43d0abb@kontron.de>
Date:   Mon, 27 Nov 2023 12:17:19 +0100
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 1/2] usb: misc: onboard_usb_hub: Add support for clock
 input
Content-Language: en-US, de-DE
To:     =?UTF-8?Q?Uwe_Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Frieder Schrempf <frieder@fris.de>, linux-kernel@vger.kernel.org,
        linux-usb@vger.kernel.org, Matthias Kaehlcke <mka@chromium.org>,
        Anand Moon <linux.amoon@gmail.com>,
        Benjamin Bara <benjamin.bara@skidata.com>,
        Icenowy Zheng <uwu@icenowy.me>, Rob Herring <robh@kernel.org>
References: <20231123134728.709533-1-frieder@fris.de>
 <2023112329-augmented-ecology-0753@gregkh>
 <20231123173610.d6ytwlpbpcqng5pv@pengutronix.de>
From:   Frieder Schrempf <frieder.schrempf@kontron.de>
In-Reply-To: <20231123173610.d6ytwlpbpcqng5pv@pengutronix.de>
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Hi Greg, hi Uwe,

thanks for reviewing!

On 23.11.23 18:36, Uwe Kleine-König wrote:
> Hello,
> 
> On Thu, Nov 23, 2023 at 01:55:57PM +0000, Greg Kroah-Hartman wrote:
>> On Thu, Nov 23, 2023 at 02:47:20PM +0100, Frieder Schrempf wrote:
>>> +	err = clk_prepare_enable(hub->clk);
>>> +	if (err) {
>>> +		dev_err(hub->dev, "failed to enable clock: %d\n", err);
>>> +		return err;
> 
> I suggest to use %pe (and ERR_PTR(err)) here.

Ok, I added this in v2. I also added a patch to convert the other error
logs to be consistent within the driver.

> 
>>> +	}
>>
>> But what happens if clk is not set here?
> 
> clk_prepare_enable() just does "return 0" if the clk argument is NULL.

Exactly!

> 
>> And doesn't clk_prepare_enable() print out a message if it fails?
> 
> clk_prepare_enable is silent on errors.

Right!

Thanks
Frieder