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

With that the only condition under which these simple iteration
functions return error is when the dm is not initialized at uclass_get
time. This is not all that interesting, change return type to void.

Fixes: 6494d708bf ("dm: Add base driver model support")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

The _err variant iterators use the simple iterators without suffix as
basis.

However, there is no user that uclass_next_device_err for iteration,
many users of uclass_first_device_err use it to get the first and
(assumed) only device of an uclass, and a couple that use
uclass_next_device_err to get the device following a known device in the
uclass list.

While there are some truly singleton device classes in which more than
one device cannot exist these are quite rare, and most classes can have
multiple devices even if it is not the case on the SoC's EVB.

In a later patch the simple iterators will be updated to not stop on
error and return next device instead. With this in many cases the code
that expects the first device or an error if it fails to probe may get
the next device instead. Use the _check iterators as the basis of _err
iterators to preserve the old behavior.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

uclass_probe_all uses uclass_first_device/uclass_next_device assigning
the return value.

The interface for getting meaningful error is
uclass_first_device_check/uclass_next_device_check, use it.

Also do not stop iteration when an error is encountered. Probing all
devices includes those that happen to be after a failing device in the
uclass order.

Fixes: a59153dfeb ("dm: core: add function uclass_probe_all() to probe all devices")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

In some cases two devices are related and the only way to tell is to
check that the names partially patch. Add a way to check this without
needing to create a new string for the comparison.

Fix the comment for device_find_child_by_namelen() while we are here.

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

It seems that namelen is more common in U-Boot. Rename this function to
fit in better. Also fix a bug where it breaks the operation of
uclass_get_by_name() and add a test.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reported-by: Tim Harvey <tharvey@gateworks.com>

Sphinx expects Return: and not @return to indicate a return value.

find . -name '*.c' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

find . -name '*.h' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

Add a function that returns some basic stats about driver model. For now
we only have two.

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

Add a function that returns the number of devices in a uclass. This can be
helpful in sizing an array that needs to hold a list of them.

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

In some cases it is useful to search just by a partial name, such as
when looking for a sibling device that has a common name substring. Add
helper functions to handle these requirements.

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

This method is currently called after the platform data has been freed.
But the pre_unbind() method may wish to access this, e.g. to free some
data structures stored there.

Split the unbinding of devices into two pieces, as is done with removal.
This corrects the problem.

Also tidy a code-style issue in device_remove() while we are here.

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