[U-Boot] [PATCH v3 01/15] serial: Use next serial device if probing fails

[Alexander Graf <agraf@suse.de>]

Currently our serial device search chokes on the fact that the serial
probe function could fail. If it does, instead of searching for the next
usable serial device, it just quits.

This patch changes the fallback logic so that even when a serial device
was not probed correctly, we just try the next ones until we find one that
works.

Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

---

v1 -> v2:

  - Make search logic easier to follow
---
 drivers/serial/serial-uclass.c | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/drivers/serial/serial-uclass.c b/drivers/serial/serial-uclass.c
index 2e5116f7ce..68ca2d09d1 100644
--- a/drivers/serial/serial-uclass.c
+++ b/drivers/serial/serial-uclass.c
@@ -74,6 +74,7 @@ static void serial_find_console_or_panic(void)
 {
 	const void *blob = gd->fdt_blob;
 	struct udevice *dev;
+	int ret;
 
 	if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
 		uclass_first_device(UCLASS_SERIAL, &dev);
@@ -104,8 +105,8 @@ static void serial_find_console_or_panic(void)
 		 * from 1!).
 		 *
 		 * Failing that, get the device with sequence number 0, or in
-		 * extremis just the first serial device we can find. But we
-		 * insist on having a console (even if it is silent).
+		 * extremis just the first working serial device we can find.
+		 * But we insist on having a console (even if it is silent).
 		 */
 #ifdef CONFIG_CONS_INDEX
 #define INDEX (CONFIG_CONS_INDEX - 1)
@@ -113,10 +114,22 @@ static void serial_find_console_or_panic(void)
 #define INDEX 0
 #endif
 		if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
-		    !uclass_get_device(UCLASS_SERIAL, INDEX, &dev) ||
-		    (!uclass_first_device(UCLASS_SERIAL, &dev) && dev)) {
-			gd->cur_serial_dev = dev;
-			return;
+		    !uclass_get_device(UCLASS_SERIAL, INDEX, &dev)) {
+			if (dev->flags & DM_FLAG_ACTIVATED) {
+				gd->cur_serial_dev = dev;
+				return;
+			}
+		}
+
+		/* Search for any working device */
+		for (ret = uclass_first_device_check(UCLASS_SERIAL, &dev);
+		     dev;
+		     ret = uclass_next_device_check(&dev)) {
+			if (!ret) {
+				/* Device did succeed probing */
+				gd->cur_serial_dev = dev;
+				return;
+			}
 		}
 #undef INDEX
 	}
-- 
2.12.3