1 files changed, 17 insertions, 98 deletions

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 57840cf90388..5f3daabdc916 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -41,8 +41,6 @@ static struct lock_class_key port_lock_key;
 
 #define HIGH_BITS_OFFSET	((sizeof(long)-sizeof(int))*8)
 
-#define SYSRQ_TIMEOUT	(HZ * 5)
-
 static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
 					struct ktermios *old_termios);
 static void uart_wait_until_sent(struct tty_struct *tty, int timeout);
@@ -1916,6 +1914,12 @@ static inline bool uart_console_enabled(struct uart_port *port)
 	return uart_console(port) && (port->cons->flags & CON_ENABLED);
 }
 
+static void __uart_port_spin_lock_init(struct uart_port *port)
+{
+	spin_lock_init(&port->lock);
+	lockdep_set_class(&port->lock, &port_lock_key);
+}
+
 /*
  * Ensure that the serial console lock is initialised early.
  * If this port is a console, then the spinlock is already initialised.
@@ -1925,8 +1929,7 @@ static inline void uart_port_spin_lock_init(struct uart_port *port)
 	if (uart_console(port))
 		return;
 
-	spin_lock_init(&port->lock);
-	lockdep_set_class(&port->lock, &port_lock_key);
+	__uart_port_spin_lock_init(port);
 }
 
 #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(CONFIG_CONSOLE_POLL)
@@ -2373,6 +2376,13 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 		uart_change_pm(state, UART_PM_STATE_ON);
 
 		/*
+		 * If this driver supports console, and it hasn't been
+		 * successfully registered yet, initialise spin lock for it.
+		 */
+		if (port->cons && !(port->cons->flags & CON_ENABLED))
+			__uart_port_spin_lock_init(port);
+
+		/*
 		 * Ensure that the modem control lines are de-activated.
 		 * keep the DTR setting that is set in uart_set_options()
 		 * We probably don't need a spinlock around this, but
@@ -3163,7 +3173,7 @@ static DECLARE_WORK(sysrq_enable_work, uart_sysrq_on);
  *	Returns false if @ch is out of enabling sequence and should be
  *	handled some other way, true if @ch was consumed.
  */
-static bool uart_try_toggle_sysrq(struct uart_port *port, unsigned int ch)
+bool uart_try_toggle_sysrq(struct uart_port *port, unsigned int ch)
 {
 	int sysrq_toggle_seq_len = strlen(sysrq_toggle_seq);
 
@@ -3186,99 +3196,9 @@ static bool uart_try_toggle_sysrq(struct uart_port *port, unsigned int ch)
 	port->sysrq = 0;
 	return true;
 }
-#else
-static inline bool uart_try_toggle_sysrq(struct uart_port *port, unsigned int ch)
-{
-	return false;
-}
+EXPORT_SYMBOL_GPL(uart_try_toggle_sysrq);
 #endif
 
-int uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
-{
-	if (!IS_ENABLED(CONFIG_MAGIC_SYSRQ_SERIAL))
-		return 0;
-
-	if (!port->has_sysrq || !port->sysrq)
-		return 0;
-
-	if (ch && time_before(jiffies, port->sysrq)) {
-		if (sysrq_mask()) {
-			handle_sysrq(ch);
-			port->sysrq = 0;
-			return 1;
-		}
-		if (uart_try_toggle_sysrq(port, ch))
-			return 1;
-	}
-	port->sysrq = 0;
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(uart_handle_sysrq_char);
-
-int uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch)
-{
-	if (!IS_ENABLED(CONFIG_MAGIC_SYSRQ_SERIAL))
-		return 0;
-
-	if (!port->has_sysrq || !port->sysrq)
-		return 0;
-
-	if (ch && time_before(jiffies, port->sysrq)) {
-		if (sysrq_mask()) {
-			port->sysrq_ch = ch;
-			port->sysrq = 0;
-			return 1;
-		}
-		if (uart_try_toggle_sysrq(port, ch))
-			return 1;
-	}
-	port->sysrq = 0;
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(uart_prepare_sysrq_char);
-
-void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long flags)
-__releases(&port->lock)
-{
-	if (port->has_sysrq) {
-		int sysrq_ch = port->sysrq_ch;
-
-		port->sysrq_ch = 0;
-		spin_unlock_irqrestore(&port->lock, flags);
-		if (sysrq_ch)
-			handle_sysrq(sysrq_ch);
-	} else {
-		spin_unlock_irqrestore(&port->lock, flags);
-	}
-}
-EXPORT_SYMBOL_GPL(uart_unlock_and_check_sysrq);
-
-/*
- * We do the SysRQ and SAK checking like this...
- */
-int uart_handle_break(struct uart_port *port)
-{
-	struct uart_state *state = port->state;
-
-	if (port->handle_break)
-		port->handle_break(port);
-
-	if (port->has_sysrq && uart_console(port)) {
-		if (!port->sysrq) {
-			port->sysrq = jiffies + SYSRQ_TIMEOUT;
-			return 1;
-		}
-		port->sysrq = 0;
-	}
-
-	if (port->flags & UPF_SAK)
-		do_SAK(state->port.tty);
-	return 0;
-}
-EXPORT_SYMBOL_GPL(uart_handle_break);
-
 EXPORT_SYMBOL(uart_write_wakeup);
 EXPORT_SYMBOL(uart_register_driver);
 EXPORT_SYMBOL(uart_unregister_driver);
@@ -3289,8 +3209,7 @@ EXPORT_SYMBOL(uart_remove_one_port);
 
 /**
  * uart_get_rs485_mode() - retrieve rs485 properties for given uart
- * @dev: uart device
- * @rs485conf: output parameter
+ * @port: uart device's target port
  *
  * This function implements the device tree binding described in
  * Documentation/devicetree/bindings/serial/rs485.txt.