asoc: codecs: retry for soundwire slave enumeration

Retry for soundwire slave enumeration during bootup before
EPROBE_DEFER to avoid soundcard enumeration failures.

Change-Id: I083ec76fc84a2b367f93a2dc166a1419a75ff8b4
Signed-off-by: Sudheer Papothi <spapothi@codeaurora.org>

asoc/codecs/wcd938x/wcd938x-slave.c

@@ -24,6 +24,8 @@
 #define SWR_SLV_MAX_DEVICES     2
 #endif /* CONFIG_DEBUG_FS */
 
+#define SWR_MAX_RETRY    5
+
 struct wcd938x_slave_priv {
 	struct swr_device *swr_slave;
 #ifdef CONFIG_DEBUG_FS
@@ -278,17 +280,24 @@ static int wcd938x_slave_bind(struct device *dev,
 	int ret = 0;
 	uint8_t devnum = 0;
 	struct swr_device *pdev = to_swr_device(dev);
+	int retry = SWR_MAX_RETRY;
 
 	if (!pdev) {
 		pr_err("%s: invalid swr device handle\n", __func__);
 		return -EINVAL;
 	}
 
-	ret = swr_get_logical_dev_num(pdev, pdev->addr, &devnum);
+	do {
+		/* Add delay for soundwire enumeration */
+		usleep_range(100, 110);
+		ret = swr_get_logical_dev_num(pdev, pdev->addr, &devnum);
+	} while (ret && --retry);
+
 	if (ret) {
 		dev_dbg(&pdev->dev,
-			"%s get devnum %d for dev addr %lx failed\n",
+			"%s get devnum %d for dev addr %llx failed\n",
 			__func__, devnum, pdev->addr);
+		ret = -EPROBE_DEFER;
 		return ret;
 	}
 	pdev->dev_num = devnum;