diff options
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 32 |
1 files changed, 26 insertions, 6 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 1a65d3e5f3c0..3a946ebe9139 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -2078,7 +2078,8 @@ static void serial8250_break_ctl(struct uart_port *port, int break_state) serial8250_rpm_put(up); } -static void wait_for_lsr(struct uart_8250_port *up, int bits) +/* Returns true if @bits were set, false on timeout */ +static bool wait_for_lsr(struct uart_8250_port *up, int bits) { unsigned int status, tmout = 10000; @@ -2093,11 +2094,11 @@ static void wait_for_lsr(struct uart_8250_port *up, int bits) udelay(1); touch_nmi_watchdog(); } + + return (tmout != 0); } -/* - * Wait for transmitter & holding register to empty - */ +/* Wait for transmitter and holding register to empty with timeout */ static void wait_for_xmitr(struct uart_8250_port *up, int bits) { unsigned int tmout; @@ -3322,6 +3323,16 @@ static void serial8250_console_restore(struct uart_8250_port *up) serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS); } +static void fifo_wait_for_lsr(struct uart_8250_port *up, unsigned int count) +{ + unsigned int i; + + for (i = 0; i < count; i++) { + if (wait_for_lsr(up, UART_LSR_THRE)) + return; + } +} + /* * Print a string to the serial port using the device FIFO * @@ -3331,13 +3342,15 @@ static void serial8250_console_restore(struct uart_8250_port *up) static void serial8250_console_fifo_write(struct uart_8250_port *up, const char *s, unsigned int count) { - int i; const char *end = s + count; unsigned int fifosize = up->tx_loadsz; + unsigned int tx_count = 0; bool cr_sent = false; + unsigned int i; while (s != end) { - wait_for_lsr(up, UART_LSR_THRE); + /* Allow timeout for each byte of a possibly full FIFO */ + fifo_wait_for_lsr(up, fifosize); for (i = 0; i < fifosize && s != end; ++i) { if (*s == '\n' && !cr_sent) { @@ -3348,7 +3361,14 @@ static void serial8250_console_fifo_write(struct uart_8250_port *up, cr_sent = false; } } + tx_count = i; } + + /* + * Allow timeout for each byte written since the caller will only wait + * for UART_LSR_BOTH_EMPTY using the timeout of a single character + */ + fifo_wait_for_lsr(up, tx_count); } /* |