dm: core: Add uclass_first/next_device_check()

Sometimes it is useful to iterate through all devices in a uclass and
skip over those which do not work correctly (e.g fail to probe). Add two
new functions to provide this feature.

The caller must check the return value each time to make sure that the
device is valid. But the device pointer is always returned.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 80 insertions, 0 deletions

diff --git a/test/dm/test-fdt.c b/test/dm/test-fdt.c
index 7c9c5debe66..dcc2ef8b652 100644
--- a/test/dm/test-fdt.c
+++ b/test/dm/test-fdt.c
@@ -339,3 +339,83 @@ static int dm_test_first_next_device(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_first_next_device, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/**
+ * check_devices() - Check return values and pointers
+ *
+ * This runs through a full sequence of uclass_first_device_check()...
+ * uclass_next_device_check() checking that the return values and devices
+ * are correct.
+ *
+ * @uts: Test state
+ * @devlist: List of expected devices
+ * @mask: Indicates which devices should return an error. Device n should
+ *	  return error (-NOENT - n) if bit n is set, or no error (i.e. 0) if
+ *	  bit n is clear.
+ */
+static int check_devices(struct unit_test_state *uts,
+			 struct udevice *devlist[], int mask)
+{
+	int expected_ret;
+	struct udevice *dev;
+	int i;
+
+	expected_ret = (mask & 1) ? -ENOENT : 0;
+	mask >>= 1;
+	ut_asserteq(expected_ret,
+		    uclass_first_device_check(UCLASS_TEST_PROBE, &dev));
+	for (i = 0; i < 4; i++) {
+		ut_asserteq_ptr(devlist[i], dev);
+		expected_ret = (mask & 1) ? -ENOENT - (i + 1) : 0;
+		mask >>= 1;
+		ut_asserteq(expected_ret, uclass_next_device_check(&dev));
+	}
+	ut_asserteq_ptr(NULL, dev);
+
+	return 0;
+}
+
+/* Test uclass_first_device_check() and uclass_next_device_check() */
+static int dm_test_first_next_ok_device(struct unit_test_state *uts)
+{
+	struct dm_testprobe_pdata *pdata;
+	struct udevice *dev, *parent = NULL, *devlist[4];
+	int count;
+	int ret;
+
+	/* There should be 4 devices */
+	count = 0;
+	for (ret = uclass_first_device_check(UCLASS_TEST_PROBE, &dev);
+	     dev;
+	     ret = uclass_next_device_check(&dev)) {
+		ut_assertok(ret);
+		devlist[count++] = dev;
+		parent = dev_get_parent(dev);
+		}
+	ut_asserteq(4, count);
+	ut_assertok(uclass_first_device_check(UCLASS_TEST_PROBE, &dev));
+	ut_assertok(check_devices(uts, devlist, 0));
+
+	/* Remove them and try again, with an error on the second one */
+	pdata = dev_get_platdata(devlist[1]);
+	pdata->probe_err = -ENOENT - 1;
+	device_remove(parent, DM_REMOVE_NORMAL);
+	ut_assertok(check_devices(uts, devlist, 1 << 1));
+
+	/* Now an error on the first one */
+	pdata = dev_get_platdata(devlist[0]);
+	pdata->probe_err = -ENOENT - 0;
+	device_remove(parent, DM_REMOVE_NORMAL);
+	ut_assertok(check_devices(uts, devlist, 3 << 0));
+
+	/* Now errors on all */
+	pdata = dev_get_platdata(devlist[2]);
+	pdata->probe_err = -ENOENT - 2;
+	pdata = dev_get_platdata(devlist[3]);
+	pdata->probe_err = -ENOENT - 3;
+	device_remove(parent, DM_REMOVE_NORMAL);
+	ut_assertok(check_devices(uts, devlist, 0xf << 0));
+
+	return 0;
+}
+DM_TEST(dm_test_first_next_ok_device, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);