On 2016-11-10 15:58:54 [+0200], Andy Shevchenko wrote: > > > > I grepped code and found no driver under 8250 which is using > > > > threaded > > > > IRQ handler. What did I miss? > > > > > > Documentation/kernel-parameters.txt: threadirqs [KNL] > > Okay, so, the scenario you perhaps concerned is: > 1. HW generates interrupt. > 2. It's queued to be handled by threads. > 3. Meanwhile the HW might be powered off (automatic suspend assumed). Tx > can't be for sure, Rx side then. But I barely imagine how it is > possible. Even if we get it powered off it should wake the system again > (via wake source, which is RxD/CTS or out-of-bound one). > 4. In the handler we check if the device suspended. So, return to the > question below. > > Where is the issue in my logic? I am not an expert here. By the time I did this, I've been told to always issue a pm_get() before touching any registers - even in interrupt handlers. If the interrupt fires, does it reset any PM timers which put the device down? In the "threaded" handler you check whether or not the device is suspended. Can or can not the timer fire after the check? Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
