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Subject: Re: [REGRESSION] hwmon: (applesmc) avoid overlong udelay()
From:   Brad Campbell <brad@fnarfbargle.com>
To:     Andreas Kemnade <andreas@kemnade.info>,
        Guenter Roeck <linux@roeck-us.net>,
        Jean Delvare <jdelvare@suse.com>
Cc:     Arnd Bergmann <arnd@arndb.de>, rydberg@bitmath.org,
        linux-hwmon@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        hns@goldelico.com
References: <20200930105442.3f642f6c@aktux>
 <20200930164446.GB219887@roeck-us.net>
 <CAK8P3a2CbhJT+B-F+cnX+uiJep9oiLM28n045-ATaVaU41u2hw@mail.gmail.com>
 <20201002002251.28462e64@aktux>
 <7543ef85-727d-96c3-947e-5b18e9e6c44d@roeck-us.net>
 <20201006090226.4275c824@kemnade.info>
 <db042e9b-be41-11b1-7059-3881b1da5c8b@fnarfbargle.com>
 <68467f1b-cea1-47ea-a4d4-8319214b072a@fnarfbargle.com>
 <20201104142057.62493c12@aktux>
 <2436afef-99c6-c352-936d-567bf553388c@fnarfbargle.com>
Message-ID: <e6b27029-81a7-f83f-f645-34c9d7c59215@fnarfbargle.com>
Date:   Thu, 5 Nov 2020 15:22:40 +1100
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On 5/11/20 1:18 pm, Brad Campbell wrote:
> I'm not entirely sure where to go from here. I'd really like some wider testing before cleaning this up and submitting it. It puts extra checks & constraints on the comms with the SMC that weren't there previously.
> 
> I guess given there doesn't appear to have been a major outcry that the driver broke in 5.9 might indicate that nobody is using it, or that it only broke on certain machines?
> 
> Can we get some guidance from the hwmon maintainers on what direction they'd like to take? I don't really want to push this forward without broader testing only to find it breaks a whole heap of machines on the basis that it fixes mine.
> 

I managed to find an iMac 12,2 to test with. Had to remove the check for bit 0x40 (that machine sets bit 0x10). Updated patch with debugging code removed attached for comment.

Regards,
Brad

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