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| author | Gabriel Matni <gabriel.matni@exfo.com> | 2018-03-22 19:15:12 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-22 21:27:44 +0100 |
| commit | c685af1108d7c303f0b901413405d68eaeac4477 (patch) | |
| tree | ea0d6e8358debb193b8eb233a0f019fe6ff152db /drivers/tty/serial | |
| parent | 7693b331d033ecda61097007330d3e7461ff7f27 (diff) | |
| download | op-kernel-dev-c685af1108d7c303f0b901413405d68eaeac4477.zip op-kernel-dev-c685af1108d7c303f0b901413405d68eaeac4477.tar.gz | |
serial: mvebu-uart: fix tx lost characters
Fixes missing characters on kernel console at low baud rates (i.e.9600).
The driver should poll TX_RDY or TX_FIFO_EMP instead of TX_EMP to ensure
that the transmitter holding register (THR) is ready to receive a new byte.
TX_EMP tells us when it is possible to send a break sequence via
SND_BRK_SEQ. While this also indicates that both the THR and the TSR are
empty, it does not guarantee that a new byte can be written just yet.
Fixes: 30530791a7a0 ("serial: mvebu-uart: initial support for Armada-3700 serial port")
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Gabriel Matni <gabriel.matni@exfo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
| -rw-r--r-- | drivers/tty/serial/mvebu-uart.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c index a4176af..750e564 100644 --- a/drivers/tty/serial/mvebu-uart.c +++ b/drivers/tty/serial/mvebu-uart.c @@ -618,7 +618,7 @@ static void wait_for_xmitr(struct uart_port *port) u32 val; readl_poll_timeout_atomic(port->membase + UART_STAT, val, - (val & STAT_TX_EMP), 1, 10000); + (val & STAT_TX_RDY(port)), 1, 10000); } static void mvebu_uart_console_putchar(struct uart_port *port, int ch) |
