On Mon, Aug 29, 2016 at 02:22:36PM -0700, Douglas Anderson wrote:

Depending on a number of factors including:
- Which exact Rockchip SoC we're working with
- How deep we suspend
- Which i2c port we're on

We might lose the state of the i2c registers at suspend time.
Specifically we've found that on rk3399 the i2c ports that are not in
the PMU power domain lose their state with the current suspend depth
configured by ARM Tursted Firmware.

Note that there are very few actual i2c registers that aren't configured
per transfer anyway so all we actually need to re-configure are the
clock config registers.  We'll just add a call to rk3x_i2c_adapt_div()
at resume time and be done with it.

NOTE: On rk3399 on ports whose power was lost, I put printouts in at
resume time.  I saw things like:
  before: con=0x00010300, div=0x00060006
  after:  con=0x00010200, div=0x00180025

Signed-off-by: Douglas Anderson <dianders@chromium.org>

Fixed the code checker warnings:

    SPARSE
drivers/i2c/busses/i2c-rk3x.c:1346:14: warning: duplicate const
    SMATCH
drivers/i2c/busses/i2c-rk3x.c:1346:14: warning: duplicate const

and applied to for-current, thanks!


Note my code checkers also say this (unrelated to your patch):

    SPARSE
drivers/i2c/busses/i2c-rk3x.c:888:17: warning: cast truncates bits from constant value (ffffffffff00 becomes ffffff00)

  CC      drivers/i2c/busses/i2c-rk3x.o
drivers/i2c/busses/i2c-rk3x.c: In function 'rk3x_i2c_v1_calc_timings':
drivers/i2c/busses/i2c-rk3x.c:745:41: warning: variable 'min_total_ns' set but not used [-Wunused-but-set-variable]

I haven't checked those, though...

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