[Qemu-devel] [PATCH v2 for-2.4] i.MX: Fix UART driver to work with unitialized "chardev" device

[Jean-Christophe Dubois]

The "chardev" property initialization might have failed (for example because
there are not enough chardevs provided by QEMU).

The serial device emulator need to be able to work with an uninitialized
(NULL) chardev device pointer.

This patch add some missing tests on the chr pointer value before
using it.

Signed-off-by: Jean-Christophe Dubois <address@hidden>
Reviewed-by: Peter Crosthwaite <address@hidden>
---

Changes since V1:
 * Grammar sweep on patch description
 * Added Peter's "Reviewed-by"

 hw/char/imx_serial.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/hw/char/imx_serial.c b/hw/char/imx_serial.c
index f3fbc77..383e50c 100644
--- a/hw/char/imx_serial.c
+++ b/hw/char/imx_serial.c
@@ -203,7 +203,9 @@ static uint64_t imx_serial_read(void *opaque, hwaddr offset,
             s->usr2 &= ~USR2_RDR;
             s->uts1 |= UTS1_RXEMPTY;
             imx_update(s);
-            qemu_chr_accept_input(s->chr);
+            if (s->chr) {
+                qemu_chr_accept_input(s->chr);
+            }
         }
         return c;
 
@@ -290,7 +292,9 @@ static void imx_serial_write(void *opaque, hwaddr offset,
         }
         if (value & UCR2_RXEN) {
             if (!(s->ucr2 & UCR2_RXEN)) {
-                qemu_chr_accept_input(s->chr);
+                if (s->chr) {
+                    qemu_chr_accept_input(s->chr);
+                }
             }
         }
         s->ucr2 = value & 0xffff;
-- 
2.1.4