dm: blk: Expand iteration and add tests
Add some functions which support iteration before probing. Also add tests
for the functions.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/blk.h b/include/blk.h
index d06098b..dbe9ae2 100644
--- a/include/blk.h
+++ b/include/blk.h
@@ -732,6 +732,51 @@
int blk_next_device_err(enum blk_flag_t flags, struct udevice **devp);
/**
+ * blk_find_first() - Return the first matching block device
+ * @flags: Indicates type of device to return
+ * @devp: Returns pointer to device, or NULL on error
+ *
+ * The device is not prepared for use - this is an internal function.
+ * The function uclass_get_device_tail() can be used to probe the device.
+ *
+ * Note that some devices are considered removable until they have been probed
+ *
+ * @return 0 if found, -ENODEV if not found
+ */
+int blk_find_first(enum blk_flag_t flags, struct udevice **devp);
+
+/**
+ * blk_find_next() - Return the next matching block device
+ * @flags: Indicates type of device to return
+ * @devp: On entry, pointer to device to lookup. On exit, returns pointer
+ * to the next device in the same uclass, or NULL if none
+ *
+ * The device is not prepared for use - this is an internal function.
+ * The function uclass_get_device_tail() can be used to probe the device.
+ *
+ * Note that some devices are considered removable until they have been probed
+ *
+ * @return 0 if found, -ENODEV if not found
+ */
+int blk_find_next(enum blk_flag_t flags, struct udevice **devp);
+
+/**
+ * blk_foreach() - iterate through block devices
+ *
+ * This creates a for() loop which works through the available block devices in
+ * order from start to end.
+ *
+ * If for some reason the uclass cannot be found, this does nothing.
+ *
+ * @_flags: Indicates type of device to return
+ * @_pos: struct udevice * to hold the current device. Set to NULL when there
+ * are no more devices.
+ */
+#define blk_foreach(_flags, _pos) \
+ for (int _ret = blk_find_first(_flags, &_pos); !_ret && _pos; \
+ _ret = blk_find_next(_flags, &_pos))
+
+/**
* blk_foreach_probe() - Helper function to iteration through block devices
*
* This creates a for() loop which works through the available devices in