V4L/DVB (8881): gspca: After 'while (retry--) {...}', retry will be -1 but not 0.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/gspca/conex.c b/drivers/media/video/gspca/conex.c
index 8c91ffd..4d9f4cc 100644
--- a/drivers/media/video/gspca/conex.c
+++ b/drivers/media/video/gspca/conex.c
@@ -731,13 +731,13 @@
 	reg_w_val(gspca_dev, 0x0000, 0x00);
 	/* wait for completion */
 	retry = 50;
-	while (retry--) {
+	do {
 		reg_r(gspca_dev, 0x0002, 1);
 							/* 0x07 until 0x00 */
 		if (gspca_dev->usb_buf[0] == 0x00)
 			break;
 		reg_w_val(gspca_dev, 0x0053, 0x00);
-	}
+	} while (--retry);
 	if (retry == 0)
 		PDEBUG(D_ERR, "Damned Errors sending jpeg Table");
 	/* send the qtable now */
diff --git a/drivers/media/video/gspca/spca561.c b/drivers/media/video/gspca/spca561.c
index 1c29c27..cfbc9eb 100644
--- a/drivers/media/video/gspca/spca561.c
+++ b/drivers/media/video/gspca/spca561.c
@@ -223,11 +223,11 @@
 	reg_w_val(gspca_dev->dev, 0x8804, 0x92);
 	reg_w_val(gspca_dev->dev, 0x8801, reg);
 	reg_w_val(gspca_dev->dev, 0x8802, (mode | 0x01));
-	while (retry--) {
+	do {
 		reg_r(gspca_dev, 0x8803, 1);
 		if (!gspca_dev->usb_buf)
 			break;
-	}
+	} while (--retry);
 	if (retry == 0)
 		return -1;
 	reg_r(gspca_dev, 0x8800, 1);