drm: count reaches -1

With a postfix decrement in the test count will reach -1 rather than 0,
subsequent tests fail.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/gpu/drm/via/via_dma.c b/drivers/gpu/drm/via/via_dma.c
index 7a339dba6a69..bfb92d283260 100644
--- a/drivers/gpu/drm/via/via_dma.c
+++ b/drivers/gpu/drm/via/via_dma.c
@@ -481,11 +481,13 @@ static int via_wait_idle(drm_via_private_t * dev_priv)
 {
         int count = 10000000;
 
-        while (!(VIA_READ(VIA_REG_STATUS) & VIA_VR_QUEUE_BUSY) && count--);
+        while (!(VIA_READ(VIA_REG_STATUS) & VIA_VR_QUEUE_BUSY) && --count)
+                ;
 
-        while (count-- && (VIA_READ(VIA_REG_STATUS) &
+        while (count && (VIA_READ(VIA_REG_STATUS) &
                            (VIA_CMD_RGTR_BUSY | VIA_2D_ENG_BUSY |
-                            VIA_3D_ENG_BUSY))) ;
+                            VIA_3D_ENG_BUSY)))
+                --count;
         return count;
 }
 
@@ -705,7 +707,7 @@ static int via_cmdbuf_size(struct drm_device *dev, void *data, struct drm_file *
         switch (d_siz->func) {
         case VIA_CMDBUF_SPACE:
                 while (((tmp_size = via_cmdbuf_space(dev_priv)) < d_siz->size)
-                       && count--) {
+                       && --count) {
                         if (!d_siz->wait) {
                                 break;
                         }
@@ -717,7 +719,7 @@ static int via_cmdbuf_size(struct drm_device *dev, void *data, struct drm_file *
                 break;
         case VIA_CMDBUF_LAG:
                 while (((tmp_size = via_cmdbuf_lag(dev_priv)) > d_siz->size)
-                       && count--) {
+                       && --count) {
                         if (!d_siz->wait) {
                                 break;
                         }