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Subject: Re: [PATCH v6 3/5] i2c: add support for HiSilicon I2C controller
To:     Jarkko Nikula <jarkko.nikula@linux.intel.com>, <wsa@kernel.org>,
        <andriy.shevchenko@linux.intel.com>, <linux-i2c@vger.kernel.org>,
        <Sergey.Semin@baikalelectronics.ru>, <linux-kernel@vger.kernel.org>
CC:     <digetx@gmail.com>, <treding@nvidia.com>,
        <rmk+kernel@armlinux.org.uk>, <song.bao.hua@hisilicon.com>,
        <john.garry@huawei.com>, <mika.westerberg@linux.intel.com>,
        <prime.zeng@huawei.com>, <linuxarm@huawei.com>
References: <1617197790-30627-1-git-send-email-yangyicong@hisilicon.com>
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 <f1d50200-93f5-2c35-933a-01a1e7622983@linux.intel.com>
From:   Yicong Yang <yangyicong@hisilicon.com>
Message-ID: <19f33eff-e7b2-0e03-bbd4-f50b2ef050c5@hisilicon.com>
Date:   Wed, 7 Apr 2021 18:16:37 +0800
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On 2021/4/7 16:32, Jarkko Nikula wrote:
> Hi
> 
> On 3/31/21 4:36 PM, Yicong Yang wrote:
>> +    ret = device_property_read_u64(dev, "clk_rate", &ctlr->clk_rate_khz);
>> +    if (ret) {
>> +        dev_err(dev, "failed to get clock frequency, ret = %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    ctlr->clk_rate_khz = DIV_ROUND_UP_ULL(ctlr->clk_rate_khz, HZ_PER_KHZ);
>> +
> 
> I'd use a temp variable here for reading the "clk_rate" property in Hertz and calculating the derived kHz value from it. As a bonus allow to use u32 for clk_rate_khz instead of u64. u32 will still provide plenty of headroom :-)
> 
> Reason for temp variable is for me it's confusing to see statement like "rate_khz = rate_khz / 1000".
> 

I can get this addressed in the updated version. Thanks for the suggestion!