diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_port.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 86 |
1 files changed, 49 insertions, 37 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 0bbf34035d6a..52d82d2ac726 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -284,7 +284,7 @@ static void default_serial_dl_write(struct uart_8250_port *up, int value) serial_out(up, UART_DLM, value >> 8 & 0xff); } -#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X) +#ifdef CONFIG_SERIAL_8250_RT288X /* Au1x00/RT288x UART hardware has a weird register layout */ static const s8 au_io_in_map[8] = { @@ -435,7 +435,7 @@ static void set_io_from_upio(struct uart_port *p) p->serial_out = mem32be_serial_out; break; -#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X) +#ifdef CONFIG_SERIAL_8250_RT288X case UPIO_AU: p->serial_in = au_serial_in; p->serial_out = au_serial_out; @@ -1246,6 +1246,9 @@ static void autoconfig_irq(struct uart_8250_port *up) inb_p(ICP); } + if (uart_console(port)) + console_lock(); + /* forget possible initially masked and pending IRQ */ probe_irq_off(probe_irq_on()); save_mcr = serial_in(up, UART_MCR); @@ -1277,6 +1280,9 @@ static void autoconfig_irq(struct uart_8250_port *up) if (port->flags & UPF_FOURPORT) outb_p(save_ICP, ICP); + if (uart_console(port)) + console_unlock(); + port->irq = (irq > 0) ? irq : 0; } @@ -1807,9 +1813,6 @@ int serial8250_do_startup(struct uart_port *port) unsigned char lsr, iir; int retval; - if (port->type == PORT_8250_CIR) - return -ENODEV; - if (!port->fifosize) port->fifosize = uart_config[port->type].fifo_size; if (!up->tx_loadsz) @@ -2230,6 +2233,23 @@ static void serial8250_set_divisor(struct uart_port *port, unsigned int baud, serial_port_out(port, 0x2, quot_frac); } +static unsigned int +serial8250_get_baud_rate(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + unsigned int tolerance = port->uartclk / 100; + + /* + * Ask the core to calculate the divisor for us. + * Allow 1% tolerance at the upper limit so uart clks marginally + * slower than nominal still match standard baud rates without + * causing transmission errors. + */ + return uart_get_baud_rate(port, termios, old, + port->uartclk / 16 / 0xffff, + (port->uartclk + tolerance) / 16); +} + void serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) @@ -2241,12 +2261,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, cval = serial8250_compute_lcr(up, termios->c_cflag); - /* - * Ask the core to calculate the divisor for us. - */ - baud = uart_get_baud_rate(port, termios, old, - port->uartclk / 16 / 0xffff, - port->uartclk / 16); + baud = serial8250_get_baud_rate(port, termios, old); quot = serial8250_get_divisor(up, baud, &frac); /* @@ -2513,14 +2528,8 @@ static void serial8250_release_port(struct uart_port *port) static int serial8250_request_port(struct uart_port *port) { struct uart_8250_port *up = up_to_u8250p(port); - int ret; - - if (port->type == PORT_8250_CIR) - return -ENODEV; - - ret = serial8250_request_std_resource(up); - return ret; + return serial8250_request_std_resource(up); } static int fcr_get_rxtrig_bytes(struct uart_8250_port *up) @@ -2668,9 +2677,6 @@ static void serial8250_config_port(struct uart_port *port, int flags) struct uart_8250_port *up = up_to_u8250p(port); int ret; - if (port->type == PORT_8250_CIR) - return; - /* * Find the region that we can probe for. This in turn * tells us whether we can probe for the type of port. @@ -2805,6 +2811,27 @@ static void serial8250_console_putchar(struct uart_port *port, int ch) } /* + * Restore serial console when h/w power-off detected + */ +static void serial8250_console_restore(struct uart_8250_port *up) +{ + struct uart_port *port = &up->port; + struct ktermios termios; + unsigned int baud, quot, frac = 0; + + termios.c_cflag = port->cons->cflag; + if (port->state->port.tty && termios.c_cflag == 0) + termios.c_cflag = port->state->port.tty->termios.c_cflag; + + baud = serial8250_get_baud_rate(port, &termios, NULL); + quot = serial8250_get_divisor(up, baud, &frac); + + serial8250_set_divisor(port, baud, quot, frac); + serial_port_out(port, UART_LCR, up->lcr); + serial_port_out(port, UART_MCR, UART_MCR_DTR | UART_MCR_RTS); +} + +/* * Print a string to the serial port trying not to disturb * any possible real use of the port... * @@ -2841,22 +2868,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s, /* check scratch reg to see if port powered off during system sleep */ if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) { - struct ktermios termios; - unsigned int baud, quot, frac = 0; - - termios.c_cflag = port->cons->cflag; - if (port->state->port.tty && termios.c_cflag == 0) - termios.c_cflag = port->state->port.tty->termios.c_cflag; - - baud = uart_get_baud_rate(port, &termios, NULL, - port->uartclk / 16 / 0xffff, - port->uartclk / 16); - quot = serial8250_get_divisor(up, baud, &frac); - - serial8250_set_divisor(port, baud, quot, frac); - serial_port_out(port, UART_LCR, up->lcr); - serial_port_out(port, UART_MCR, UART_MCR_DTR | UART_MCR_RTS); - + serial8250_console_restore(up); up->canary = 0; } |