On Tue, Jan 11, 2011 at 00:16, Mike Frysinger wrote: > From: Sonic Zhang <sonic.zhang@xxxxxxxxxx> > > The RX lock is used to protect the RX buffer from concurrent access in DMA > mode between the timer and RX interrupt routines. ÂIt is independent from > the uart lock which is used to protect the TX buffer. ÂIt is possible for > a uart TX transfer to be started up from the RX interrupt handler if low > latency is enabled. ÂSo we need to split the locks to avoid deadlocking in > this situation. > > In PIO mode, the RX lock is not necessary because the handle_simple_irq > and handle_level_irq functions ensure driver interrupt handlers are called > once on one core. > > And now that the RX path has its own lock, the TX interrupt has nothing to > do with the RX path, so disabling it at the same time. ping ... -mike -- 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
