[PATCH 1/2] dm: clarify DM_FLAG_PROBE_AFTER_BIND behaviour

[Caleb Connolly]

The DM_FLAG_PROBE_AFTER_BIND flag only makes sense on a per-device
basis, however recently added documentation as well as some confused
drivers imply that it might be added to a driver definition, this does
nothing.

Clarify the new documentation and expand on the comment by the
definition to point people in the right direction.

Signed-off-by: Caleb Connolly <caleb.connolly at linaro.org>
---
Anecdotally, I've spent several hours being confused about this flag,
this information would have helped me greatly.
---
 doc/develop/driver-model/design.rst | 6 ++++--
 include/dm/device.h                 | 5 ++++-
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/doc/develop/driver-model/design.rst b/doc/develop/driver-model/design.rst
index 92f638a02047..30093737200c 100644
--- a/doc/develop/driver-model/design.rst
+++ b/doc/develop/driver-model/design.rst
@@ -842,10 +842,12 @@ steps (see device_probe()):
       cause the uclass to do some housekeeping to record the device as
       activated and 'known' by the uclass.
 
 For some platforms, certain devices must be probed to get the platform into
-a working state. To help with this, drivers marked with DM_FLAG_PROBE_AFTER_BIND
-will be probed immediately after all devices are bound. For now, this happens in
+a working state. To help with this, devices marked with DM_FLAG_PROBE_AFTER_BIND
+will be probed immediately after all devices are bound. This flag must be set
+on the device in its ``bind()`` function with
+``dev_or_flags(dev, DM_FLAG_PROBE_AFTER_BIND)``. For now, this happens in
 SPL, before relocation and after relocation. See the call to ``dm_autoprobe()``
 for where this is done.
 
 The auto-probe feature is tricky because it bypasses the normal ordering of
diff --git a/include/dm/device.h b/include/dm/device.h
index add67f9ec06f..678cd83c2716 100644
--- a/include/dm/device.h
+++ b/include/dm/device.h
@@ -80,9 +80,12 @@ struct driver_info;
  * e.g. for clock, which need to be active during the device-removal phase.
  */
 #define DM_FLAG_VITAL			(1 << 14)
 
-/* Device must be probed after it was bound */
+/* Device must be probed after it was bound. This flag is per-device and does
+ * nothing if set on a U_BOOT_DRIVER() definition. Apply it with
+ * dev_or_flags(dev, DM_FLAG_PROBE_AFTER_BIND) in the devices bind function.
+ */
 #define DM_FLAG_PROBE_AFTER_BIND	(1 << 15)
 
 /*
  * One or multiple of these flags are passed to device_remove() so that

-- 
2.48.0