[PATCH RFC 0/3] clk: imx28: add DC-DC clock domain

From: Stefan Wahren
Date: Mon Apr 20 2015 - 17:46:04 EST


This patch series integrates the DC-DC clock domain into the i.MX28 clock
driver. That enables consumers to change DC-DC clock frequency in order to avoid
interferences without changing hardware. The final patch in the near future
should handle the i.MX23, too.

* patch 1 contains the update for the DT binding documentation
* patch 2 defines the PMU as the clock consumer
* patch 3 is extension of the clock driver

All information about the DC-DC clock was taken from the reference manual [1].
Unfortunately the logical diagram doesn't contain the DC-DC clock domain,
so i decide to create a ASCII diagramm (please look at patch 1).

The series is related to the upcoming MXS PMU and regulator driver
(last patch [2], working repo [3]).

At the end i still have a question:

The MXS PMU driver will using the syscon interface for accessing the
HW_POWER registers. The ctrl register for the DC-DC clock domain is located
under HW_POWER and not under HW_CLKCTRL.

So should the clock registration be done in clock driver like in patch 3 or
in the upcoming PMU driver?

Any other comments about the implementation are also welcome.

Regards
Stefan

[1] - http://cache.freescale.com/files/dsp/doc/ref_manual/MCIMX28RM.pdf
i.MX28 Applications Processor Reference Manual, Rev. 2, 08/2013
11.12.10 DC-DC Miscellaneous Register (HW_POWER_MISC)
[2] - http://marc.info/?l=linux-pm&m=142698428606221&w=2
[3] - https://github.com/lategoodbye/linux-mxs-power/tree/syscon

Stefan Wahren (3):
DT: imx28-clock: add ids for DC-DC clock domain
ARM: imx28: define PMU as clock consumer
clk: imx28: add DC-DC clock domain

.../devicetree/bindings/clock/imx28-clock.txt | 3 ++
arch/arm/boot/dts/imx28.dtsi | 2 ++
drivers/clk/mxs/clk-imx28.c | 33 +++++++++++++++++---
3 files changed, 33 insertions(+), 5 deletions(-)

--
1.7.9.5

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