[PATCH v4 2/2] bootstd: Make bootdev_next_prio() continue after failure

[Simon Glass]

When a device fails to probe, the next device should be tried, until
either we find a suitable device or run out of devices. A device
should never be tried twice.

When we run out of devices of a particular priority, the hunter should
be used to generate devices of the next priority. Only if all attempts
fail should this function return an error.

Update the function to use the latent 'found' boolean to determine
whether another loop iteration is warranted, rather than setting 'dev'
to NULL, which creates confusion, suggesting that no devices have been
scanned and the whole process is starting from the beginning.

Note that the upcoming bootflow_efi() test is used to test this
behaviour.

Signed-off-by: Simon Glass <sjg at chromium.org>
Fixes: https://source.denx.de/u-boot/custodians/u-boot-dm/-/issues/17
---

Changes in v4:
- Split bootstd patches into a separate series

Changes in v2:
 - Add many new patches to resolve all the outstanding test issues

 boot/bootdev-uclass.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/boot/bootdev-uclass.c b/boot/bootdev-uclass.c
index 15a8a3555c6..807f8dfb064 100644
--- a/boot/bootdev-uclass.c
+++ b/boot/bootdev-uclass.c
@@ -640,6 +640,7 @@ int bootdev_next_prio(struct bootflow_iter *iter, struct udevice **devp)
 	*devp = NULL;
 	log_debug("next prio %d: dev=%p/%s\n", iter->cur_prio, dev,
 		  dev ? dev->name : "none");
+	found = false;
 	do {
 		/*
 		 * Don't probe devices here since they may not be of the
@@ -682,13 +683,13 @@ int bootdev_next_prio(struct bootflow_iter *iter, struct udevice **devp)
 			}
 		} else {
 			ret = device_probe(dev);
-			if (ret) {
+			if (ret)
 				log_debug("Device '%s' failed to probe\n",
 					  dev->name);
-				dev = NULL;
-			}
+			else
+				found = true;
 		}
-	} while (!dev);
+	} while (!found);
 
 	*devp = dev;
 
-- 
2.34.1