Kevin Hilman wrote:
Mark Lokowich <[EMAIL PROTECTED]> writes:Revert double IIR test in 8250 driverCan you give a more detailed description of what the problem is that is being fixed?
Without this patch, serial console behavior is strange. You type and nothing is echoed and you hit return and things happen. It feels like two processes are grabbing input.
I think someone posted a more technical description, but I couldn't find it quickly.
Philip
This is in the generic 8250 driver so will affect all platforms. For this to be accepted, it should be discussed on linux-serial[1] KevinAcked-by: Jaswinder Singh <[EMAIL PROTECTED]> --- --- linux-2.6/drivers/serial/8250.c +++ linux-2.6-vanilla/drivers/serial/8250.c @@ -1867,7 +1867,6 @@ } if (is_real_interrupt(up->port.irq)) { - unsigned char iir1; /* * Test for UARTs that do not reassert THRE when the * transmitter is idle and the interrupt has already @@ -1881,7 +1880,7 @@ wait_for_xmitr(up, UART_LSR_THRE); serial_out_sync(up, UART_IER, UART_IER_THRI); udelay(1); /* allow THRE to set */ - iir1 = serial_in(up, UART_IIR); + serial_in(up, UART_IIR); serial_out(up, UART_IER, 0); serial_out_sync(up, UART_IER, UART_IER_THRI); udelay(1); /* allow a working UART time to re-assert THRE */ @@ -1894,7 +1893,7 @@ * If the interrupt is not reasserted, setup a timer to * kick the UART on a regular basis. */ - if (!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) { + if (iir & UART_IIR_NO_INT) { pr_debug("ttyS%d - using backup timer\n", port->line); up->timer.function = serial8250_backup_timeout; up->timer.data = (unsigned long)up; _______________________________________________ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source[1] From MAINTAINERS: 8250/16?50 (AND CLONE UARTS) SERIAL DRIVER L: [EMAIL PROTECTED] W: http://serial.sourceforge.net S: Orphan _______________________________________________ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
smime.p7s
Description: S/MIME Cryptographic Signature
_______________________________________________ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source