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path: root/drivers/tty/serial/8250/8250_port.c
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Diffstat (limited to 'drivers/tty/serial/8250/8250_port.c')
-rw-r--r--drivers/tty/serial/8250/8250_port.c86
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;
}