In the case when I am flow controlled (meaning I received a Xoff from the other end) and my receive buffer fills up, sending a Xoff to the other end might overflow the buffer for the other guy, right ? Is that Ok ? On Mon, May 7, 2012 at 3:50 PM, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote: > On Mon, 7 May 2012 15:00:50 -0500 > Karthik Manamcheri <karthik.manamcheri@xxxxxxxxx> wrote: > >> Hi, >> >> I noticed in drivers/tty/serial/8250.c that when we transmit >> characters (by calling transmit_chars), we check for uart_tx_stopped >> only after sending the x_char (if any). What's the rationale behind >> this ? I would expect the uart not to send ANY characters (including a >> Xoff character) if its throttled (or stopped). > > We implement xon/xoff flow control. Therefore we need to send characters > when throttled. > > Think about the case where you are flow controlled for transmit and your > receive buffer fills up... > > Alan -- Karthik Manamcheri Software R&D | Instrument Control Products | National Instruments http://www.karthikmanamcheri.com http://www.linkedin.com/in/kmanamcheri -- 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
