serial: PL011: move interrupt clearing

commit c3d8b76f61586714cdc5f219ba45592a54caaa55 upstream.

Commit 360f748b204275229f8398cb2f9f53955db1503b
"serial: PL011: clear pending interrupts"
attempts to clear interrupts by writing to a
yet-unassigned memory address. This fixes the issue.

The breaking patch is marked for stable so should be
carried along with the other patch.

Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Nicolas Pitre <nico@fluxnic.net>
Reported-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index dddc3f2..6da8cf8 100644 (file)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -1919,10 +1919,6 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
                goto unmap;
        }
 
-       /* Ensure interrupts from this UART are masked and cleared */
-       writew(0, uap->port.membase + UART011_IMSC);
-       writew(0xffff, uap->port.membase + UART011_ICR);
-
        uap->vendor = vendor;
        uap->lcrh_rx = vendor->lcrh_rx;
        uap->lcrh_tx = vendor->lcrh_tx;
@@ -1939,6 +1935,10 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
        uap->port.line = i;
        pl011_dma_probe(uap);
 
+       /* Ensure interrupts from this UART are masked and cleared */
+       writew(0, uap->port.membase + UART011_IMSC);
+       writew(0xffff, uap->port.membase + UART011_ICR);
+
        snprintf(uap->type, sizeof(uap->type), "PL011 rev%u", amba_rev(dev));
 
        amba_ports[i] = uap;