[ALSA] hda-intel - Add barrier

Add proper barriers in the RIRB communication code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 5 insertions, 2 deletions

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 9a20fb1bef4f..557f269f83ab 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -536,8 +536,9 @@ static void azx_update_rirb(struct azx *chip)
                 if (res_ex & ICH6_RIRB_EX_UNSOL_EV)
                         snd_hda_queue_unsol_event(chip->bus, res, res_ex);
                 else if (chip->rirb.cmds) {
-                        chip->rirb.cmds--;
                         chip->rirb.res = res;
+                        smp_wmb();
+                        chip->rirb.cmds--;
                 }
         }
 }
@@ -556,8 +557,10 @@ static unsigned int azx_rirb_get_response(struct hda_codec *codec)
                         azx_update_rirb(chip);
                         spin_unlock_irq(&chip->reg_lock);
                 }
-                if (!chip->rirb.cmds)
+                if (!chip->rirb.cmds) {
+                        smp_rmb();
                         return chip->rirb.res; /* the last value */
+                }
                 if (time_after(jiffies, timeout))
                         break;
                 if (codec->bus->needs_damn_long_delay)