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SubjectRe: [PATCH 4/5] cpufreq: imx6q: add ldo-bypass support
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Hi Tim,

On Fri, Oct 31, 2014 at 2:27 AM, Tim Harvey <tharvey@gateworks.com> wrote:
> When an external PMIC is used for VDD_SOC and VDD_ARM you can save power by
> bypassing the internal LDO's provided by the anantop regulator as long as
> you are running less than 1.2GHz. If running at 1.2GHz the IMX6 datasheets
> state that you must use the internal LDO's to reduce ripple on the suplies.
>
> A failure to bypass the LDO's when using an external PMIC will result in an
> extra voltage drop (~125mV) between VDD_ARM_IN and VDD_ARM and VDD_SOC_IN and
> VDD_SOC which violates the voltages specificed by the datasheets.
>
> Cc: Philipp Zabel <p.zabel@pengutronix.de>
> Cc: Shawn Guo <shawn.guo@freescale.com>
> Signed-off-by: Tim Harvey <tharvey@gateworks.com>
> ---
> drivers/cpufreq/imx6q-cpufreq.c | 51 +++++++++++++++++++++++++++++++++++++++++

Shouldn't the LDO bypass support be added into the anatop regulator
driver instead?

What if someone wants to use LDO bypass and not use the cpufreq driver?


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