Commit 2389b272 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Russell King

[ARM] 4417/1: Serial: Fix AMBA drivers locking

The -rt patch triggered a lockdep warning in the amba serial drivers, which never
shows up on UP kernels. On SMP systems this would trigger as well.

Release the port lock before calling tty_flip_buffer_push() and reacquire it after
the call. This matches the code in the 8250 serial driver.
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 2ccdd1e7
...@@ -167,8 +167,9 @@ static void pl010_rx_chars(struct uart_amba_port *uap) ...@@ -167,8 +167,9 @@ static void pl010_rx_chars(struct uart_amba_port *uap)
ignore_char: ignore_char:
status = readb(uap->port.membase + UART01x_FR); status = readb(uap->port.membase + UART01x_FR);
} }
spin_unlock(&port->lock);
tty_flip_buffer_push(tty); tty_flip_buffer_push(tty);
return; spin_lock(&port->lock);
} }
static void pl010_tx_chars(struct uart_amba_port *uap) static void pl010_tx_chars(struct uart_amba_port *uap)
......
...@@ -153,8 +153,9 @@ static void pl011_rx_chars(struct uart_amba_port *uap) ...@@ -153,8 +153,9 @@ static void pl011_rx_chars(struct uart_amba_port *uap)
ignore_char: ignore_char:
status = readw(uap->port.membase + UART01x_FR); status = readw(uap->port.membase + UART01x_FR);
} }
spin_unlock(&uap->port.lock);
tty_flip_buffer_push(tty); tty_flip_buffer_push(tty);
return; spin_lock(&uap->port.lock);
} }
static void pl011_tx_chars(struct uart_amba_port *uap) static void pl011_tx_chars(struct uart_amba_port *uap)
......
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