Linux-libre 4.4-gnupck-4.4-gnu

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 8bbb51fff..5a85bbaa2 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;
 	}