A device may need the controller up during suspend_noirq or resume_noirq. But if the controller is autosuspended, there is no way to wakeup it during suspend_noirq or resume_noirq because runtime pm is disabled at this time. The suspend callback wakes up the controller, so it is available until its suspend_noirq callback (pm_runtime_force_suspend). During the resume, it's restored by resume_noirq callback (pm_runtime_force_resume). Then resume callback enables autosuspend. So the controller is up during a little time slot in suspend and resume sequences even if it's not used. Signed-off-by: Thomas Richard <thomas.richard@xxxxxxxxxxx> --- drivers/i2c/busses/i2c-omap.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 42165ef57946..57f0738fa748 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -1575,9 +1575,24 @@ static int __maybe_unused omap_i2c_runtime_resume(struct device *dev) return 0; } + +static int omap_i2c_suspend(struct device *dev) +{ + return pm_runtime_resume_and_get(dev); +} + +static int omap_i2c_resume(struct device *dev) +{ + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + return 0; +} + static const struct dev_pm_ops omap_i2c_pm_ops = { SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) + SET_SYSTEM_SLEEP_PM_OPS(omap_i2c_suspend, omap_i2c_resume) SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend, omap_i2c_runtime_resume, NULL) }; -- 2.39.2