1 files changed, 18 insertions, 3 deletions

diff --git a/drivers/usb/host/whci/pzl.c b/drivers/usb/host/whci/pzl.c
index 8d62df0c330b..34d3a0aeab2b 100644
--- a/drivers/usb/host/whci/pzl.c
+++ b/drivers/usb/host/whci/pzl.c
@@ -195,11 +195,26 @@ void pzl_stop(struct whc *whc)
                       1000, "stop PZL");
 }
 
+/**
+ * pzl_update - request a PZL update and wait for the hardware to be synced
+ * @whc: the WHCI HC
+ * @wusbcmd: WUSBCMD value to start the update.
+ *
+ * If the WUSB HC is inactive (i.e., the PZL is stopped) then the
+ * update must be skipped as the hardware may not respond to update
+ * requests.
+ */
 void pzl_update(struct whc *whc, uint32_t wusbcmd)
 {
-        whc_write_wusbcmd(whc, wusbcmd, wusbcmd);
-        wait_event(whc->periodic_list_wq,
-                   (le_readl(whc->base + WUSBCMD) & WUSBCMD_PERIODIC_UPDATED) == 0);
+        struct wusbhc *wusbhc = &whc->wusbhc;
+
+        mutex_lock(&wusbhc->mutex);
+        if (wusbhc->active) {
+                whc_write_wusbcmd(whc, wusbcmd, wusbcmd);
+                wait_event(whc->periodic_list_wq,
+                           (le_readl(whc->base + WUSBCMD) & WUSBCMD_PERIODIC_UPDATED) == 0);
+        }
+        mutex_unlock(&wusbhc->mutex);
 }
 
 static void update_pzl_hw_view(struct whc *whc)