> @@ -2325,10 +2323,19 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, > if ((baud < 2400 && !up->dma) || fifo_bug) { > fcr &= ~UART_FCR_TRIGGER_MASK; > fcr |= UART_FCR_TRIGGER_1; > + /* Don't use user setting RX trigger */ > + up->fcr = 0; This breaks set fcr via sysfs set baud rate below 2400 set baud rate higher If baud < 2400 and the user has set a value then probably we should honour it. If fifo_bug is set then we should never honour it (and should perhaps eventually error it in the sysfs set). > +static unsigned char convert_fcr2val(struct uart_8250_port *up, > + unsigned char fcr) > +{ > + unsigned char val = 0, trig_raw = fcr & UART_FCR_TRIGGER_MASK; > + > + switch (up->port.type) { > + case PORT_16550A: > + if (trig_raw == UART_FCR_R_TRIG_00) > + val = 1; > + else if (trig_raw == UART_FCR_R_TRIG_01) > + val = 4; > + else if (trig_raw == UART_FCR_R_TRIG_10) > + val = 8; > + else if (trig_raw == UART_FCR_R_TRIG_11) > + val = 14; > + break; Surely the default case should be returning 1 not 0 ? > +static int convert_val2rxtrig(struct uart_8250_port *up, unsigned char val) > +{ > + switch (up->port.type) { > + case PORT_16550A: > + if (val == 1) > + return UART_FCR_R_TRIG_00; > + else if (val == 4) > + return UART_FCR_R_TRIG_01; > + else if (val == 8) > + return UART_FCR_R_TRIG_10; > + else if (val == 14) > + return UART_FCR_R_TRIG_11; What happens if you specify a meaningless value. Doing exact matching means that you have to know the hardware exactly. How about if (val < 4) return UART_FCR_R_TRIG_00; else if (val < 8) return UART_FCR_R_TRIG_01; else if (val < 14) return UART_FCR_R_TRIG_10; else return UART_FCR_R_TRIG_11; so you get the nearest lower value that the hardware can provide ? > + break; > + default: > + pr_info("Not support RX-trigger setting for this serial %u\n", > + up->port.type); That lets users spew into the logs. I think actually you just want default: return -EOPNOTSUPP; or similar Otherwise this looks good to me. The interface is sensible, it can be expanded easily to other devices and device types, and the logic looks right. Alan -- 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