[PATCH v2] dm: core: Do not stop uclass iteration on error.

[Michal Suchanek]

When probing a device fails NULL pointer is returned, and other devices
cannot be iterated. Skip to next device on error instead.

Fixes: 6494d708bf ("dm: Add base driver model support")
Signed-off-by: Michal Suchanek <msuchanek at suse.de>
---
v2: Fix up tests

Note: there is seemingly bogus repeated device_remove(parent, DM_REMOVE_NORMAL);
but I have no idea what the intent was, and fixing that is out of the
scope of this patch anyway.

 drivers/core/uclass.c | 30 +++++++++++++++++++++---------
 test/dm/test-fdt.c    | 20 ++++++++++++++++----
 2 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/drivers/core/uclass.c b/drivers/core/uclass.c
index 08d9ed82de..ccf7d59141 100644
--- a/drivers/core/uclass.c
+++ b/drivers/core/uclass.c
@@ -574,16 +574,31 @@ int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent,
 }
 #endif
 
+/* Starting from the given device return first device in the uclass that probes successfully */
+static int __uclass_next_device(struct udevice *dev, int ret, struct udevice **devp)
+{
+	if (!dev) {
+		*devp = dev;
+		return 0;
+	}
+	while ((ret = uclass_get_device_tail(dev, ret, devp))) {
+		ret = uclass_find_next_device(&dev);
+		if (!dev) {
+			*devp = dev;
+			return 0;
+		}
+	}
+
+	return ret;
+}
+
 int uclass_first_device(enum uclass_id id, struct udevice **devp)
 {
-	struct udevice *dev;
+	struct udevice *dev = NULL;
 	int ret;
 
-	*devp = NULL;
 	ret = uclass_find_first_device(id, &dev);
-	if (!dev)
-		return 0;
-	return uclass_get_device_tail(dev, ret, devp);
+	return __uclass_next_device(dev, ret, devp);
 }
 
 int uclass_first_device_err(enum uclass_id id, struct udevice **devp)
@@ -604,11 +619,8 @@ int uclass_next_device(struct udevice **devp)
 	struct udevice *dev = *devp;
 	int ret;
 
-	*devp = NULL;
 	ret = uclass_find_next_device(&dev);
-	if (!dev)
-		return 0;
-	return uclass_get_device_tail(dev, ret, devp);
+	return __uclass_next_device(dev, ret, devp);
 }
 
 int uclass_next_device_err(struct udevice **devp)
diff --git a/test/dm/test-fdt.c b/test/dm/test-fdt.c
index 6118ad42ca..165b4f5554 100644
--- a/test/dm/test-fdt.c
+++ b/test/dm/test-fdt.c
@@ -417,16 +417,28 @@ static int dm_test_first_next_device(struct unit_test_state *uts)
 	pdata = dev_get_plat(dev);
 	pdata->probe_err = -ENOMEM;
 	device_remove(parent, DM_REMOVE_NORMAL);
-	ut_assertok(uclass_first_device(UCLASS_TEST_PROBE, &dev));
-	ut_asserteq(-ENOMEM, uclass_next_device(&dev));
-	ut_asserteq_ptr(dev, NULL);
+	for (ret = uclass_first_device(UCLASS_TEST_PROBE, &dev), count = 0;
+	     dev;
+	     ret = uclass_next_device(&dev)) {
+		count++;
+		parent = dev_get_parent(dev);
+		}
+	ut_assertok(ret);
+	ut_asserteq(3, count);
 
 	/* Now an error on the first one */
 	ut_assertok(uclass_get_device(UCLASS_TEST_PROBE, 0, &dev));
 	pdata = dev_get_plat(dev);
 	pdata->probe_err = -ENOENT;
 	device_remove(parent, DM_REMOVE_NORMAL);
-	ut_asserteq(-ENOENT, uclass_first_device(UCLASS_TEST_PROBE, &dev));
+	for (ret = uclass_first_device(UCLASS_TEST_PROBE, &dev), count = 0;
+	     dev;
+	     ret = uclass_next_device(&dev)) {
+		count++;
+		parent = dev_get_parent(dev);
+		}
+	ut_assertok(ret);
+	ut_asserteq(2, count);
 
 	return 0;
 }
-- 
2.37.1