scsi: ufs: host: Hold reference returned by of_parse_phandle()

In ufshcd_populate_vreg(), we should hold the reference returned by
of_parse_phandle() and then use it to call of_node_put() for refcount
balance.

Link: https://lore.kernel.org/r/20220719071529.1081166-1-windhl@126.com
Fixes: aa4976130934 ("ufs: Add regulator enable support")
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/ufs/host/ufshcd-pltfrm.c b/drivers/ufs/host/ufshcd-pltfrm.c
index e7332cc..173aea8 100644 (file)
--- a/drivers/ufs/host/ufshcd-pltfrm.c
+++ b/drivers/ufs/host/ufshcd-pltfrm.c
@@ -108,9 +108,20 @@ out:
        return ret;
 }
 
+static bool phandle_exists(const struct device_node *np,
+                          const char *phandle_name, int index)
+{
+       struct device_node *parse_np = of_parse_phandle(np, phandle_name, index);
+
+       if (parse_np)
+               of_node_put(parse_np);
+
+       return parse_np != NULL;
+}
+
 #define MAX_PROP_SIZE 32
 static int ufshcd_populate_vreg(struct device *dev, const char *name,
-               struct ufs_vreg **out_vreg)
+                               struct ufs_vreg **out_vreg)
 {
        char prop_name[MAX_PROP_SIZE];
        struct ufs_vreg *vreg = NULL;
@@ -122,7 +133,7 @@ static int ufshcd_populate_vreg(struct device *dev, const char *name,
        }
 
        snprintf(prop_name, MAX_PROP_SIZE, "%s-supply", name);
-       if (!of_parse_phandle(np, prop_name, 0)) {
+       if (!phandle_exists(np, prop_name, 0)) {
                dev_info(dev, "%s: Unable to find %s regulator, assuming enabled\n",
                                __func__, prop_name);
                goto out;