V4L/DVB (8331): cx18: Add locking for struct cx18 GPIO state variables

cx18: Add locking for struct cx18 GPIO state variables in
anticpation of adding IR microcontroller reset support for
use by external IR modules.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/cx18/cx18-ioctl.c b/drivers/media/video/cx18/cx18-ioctl.c
index 6eaf77b..146a4b8 100644
--- a/drivers/media/video/cx18/cx18-ioctl.c
+++ b/drivers/media/video/cx18/cx18-ioctl.c
@@ -716,8 +716,10 @@
 	cx18_get_audio_input(cx, cx->audio_input, &audin);
 	CX18_INFO("Video Input: %s\n", vidin.name);
 	CX18_INFO("Audio Input: %s\n", audin.name);
+	mutex_lock(&cx->gpio_lock);
 	CX18_INFO("GPIO:  direction 0x%08x, value 0x%08x\n",
 		cx->gpio_dir, cx->gpio_val);
+	mutex_unlock(&cx->gpio_lock);
 	CX18_INFO("Tuner: %s\n",
 		test_bit(CX18_F_I_RADIO_USER, &cx->i_flags) ?  "Radio" : "TV");
 	cx2341x_log_status(&cx->params, cx->name);