On Thu, Feb 03, 2011 at 01:29:08AM -0500, Mike Frysinger wrote: > 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. It is independent from > > the uart lock which is used to protect the TX buffer. It is possible for > > a uart TX transfer to be started up from the RX interrupt handler if low > > latency is enabled. So 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 ... Is this needed for .38? thanks, greg k-h -- 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
