Hi Wolfram
> On resume, reinit hardware to ensure state machine and clock settings
> are proper. This code assumes:
>
> * bus clock is a fixed value, so no need to recalculate timings after probe
> * handling RuntimePM is not needed, because register content is kept
> when disabling the IP core clock
>
> Tested with r8a7796 (M3-W) and r8a7790 (H2).
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> ---
(snip)
> +static int rcar_i2c_resume(struct device *dev)
> +{
> + struct rcar_i2c_priv *priv = dev_get_drvdata(dev);
> +
> + rcar_i2c_init(priv);
> +
> + return 0;
> +}
Current i2c-rcar driver probe is doing
static int rcar_i2c_probe(xxx)
{
...
pm_runtime_get_sync(dev);
...
rcar_i2c_init(priv);
...
pm_runtime_put(dev);
...
}
Thus, just calling rcar_i2c_init() is not enough ?
Current driver is calling pm_runtime_get/put probe timing,
transfer timing, and more for register settings purpose.
But in my opinion, all register settings should be merged in one please
(= transfer function) and call pm_runtime_get/put there only.
R-Car I2C is not related, but I2C power domain might be
power OFF if SoC has power domain control feature (SH-Mobile has it).
In such case, register value which was set on probe timing doesn't
exist when transfer timing.
This can be increasing patch or something like that.
Best regards
---
Kuninori Morimoto
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