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SubjectRe: [PATCH 2/3] mmc: Add mmc_vddrange_to_ocrmask() helper function
On Thu, 30 Oct 2008 22:56:32 +0300
Anton Vorontsov <avorontsov@ru.mvista.com> wrote:

> +/**
> + * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
> + * @vdd_min: minimum voltage value (mV)
> + * @vdd_max: maximum voltage value (mV)
> + * @mask: pointer to the mask
> + *

Why the pointer? Why not let the caller handle the aggregation? That
would be a lot safer.

> + /* fill the mask, from max bit to min bit */
> + while (vdd_max >= vdd_min)
> + *mask |= 1 << vdd_max--;
> + return 0;

Many cards get a bit uppity with a single bit set. If possible, try to
make this function set two bits when the voltage is right on the
boundary (e.g. 3.3V).

Rgds
--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
rdesktop, core developer http://www.rdesktop.org

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