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Date: Fri, 19 Jul 2013 09:15:39 +0300
Message-ID: <CAGH3droXKeE7diARCZQ=n37XkAmYzrcUkyZLvcWjWVLHvJnWVw@mail.gmail.com>
Subject: Re: [PATCH] iio: core: Avoid double minus in sysfs output
From: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
To: Lars-Peter Clausen <lars@metafoo.de>
Cc: Oleksandr Kravchenko <x0199363@ti.com>, jic23@cam.ac.uk,
        linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org
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On Thu, Jul 18, 2013 at 7:24 PM, Lars-Peter Clausen <lars@metafoo.de> wrote:
> On 07/18/2013 05:47 PM, Oleksandr Kravchenko wrote:
>> From: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
>>
>> This patch fixes the issue with double minus in output when
>> reading channels from sysfs for IIO_VAL_INT_PLUS_MICRO and
>> IIO_VAL_INT_PLUS_NANO cases. Until this patch if val and val2
>> both are negatives output string contains "--" before
>> digits. It is result of "-%d..." in sprintf() format.
>>
>
> Hm, this might be a bug in a driver that is triggering this. The idea is
> that val2 is only allowed to be negative if val is 0.
>
> - Lars
>
If I calculate val and val2 in next way:
*val = adc / 1000000;
*val2 = adc % 1000000;
both val and val2 could by negative. Do I have to check it in my driver?