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@xxxxxxxxxxxx>
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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