[ Upstream commit 3bd4edd67b034f8e1f61c86e0eb098de6179e3f2 ]

Although unlikely, devm_pm_runtime_enable() can fail due to memory
allocations. Without proper error handling, the subsequent
pm_runtime_resume_and_get() call may operate on incorrectly
initialized runtime PM state.

Add error handling to check the return value of
devm_pm_runtime_enable() and return on failure.

Fixes: 25f7d74d4514 ("hwspinlock: omap: Use devm_pm_runtime_enable() helper")
Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn>
Link: https://patch.msgid.link/20251124104805.135-1-vulab@iscas.ac.cn
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

hwspin_lock_get_id() has been unused since the original 2011
commit bd9a4c7df256 ("drivers: hwspinlock: add framework")

Remove it and the corresponding docs.

Note that the of_hwspin_lock_get_id() version is still in use,
so leave that alone.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241215022023.181435-1-linux@treblig.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

devm_hwspin_lock_request() was added by 2018's
commit 4f1acd758b08 ("hwspinlock: Add devm_xxx() APIs to request/free
hwlock") however, it's never been used, everyone uses the
devm_hwspin_lock_request_specific() call instead.

Remove it.

Similarly, the none-devm variant isn't used.
Remove it, and the referring documentation.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241027205445.239108-1-linux@treblig.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

The continual trickle of small conversion patches is grating on me, and
is really not helping.  Just get rid of the 'remove_new' member
function, which is just an alias for the plain 'remove', and had a
comment to that effect:

  /*
   * .remove_new() is a relic from a prototype conversion of .remove().
   * New drivers are supposed to implement .remove(). Once all drivers are
   * converted to not use .remove_new any more, it will be dropped.
   */

This was just a tree-wide 'sed' script that replaced '.remove_new' with
'.remove', with some care taken to turn a subsequent tab into two tabs
to make things line up.

I did do some minimal manual whitespace adjustment for places that used
spaces to line things up.

Then I just removed the old (sic) .remove_new member function, and this
is the end result.  No more unnecessary conversion noise.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Implement a new operation qcom_hwspinlock_bust() which can be invoked
to bust any locks that are in use when a remoteproc is stopped or
crashed.

Signed-off-by: Richard Maina <quic_rmaina@quicinc.com>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Chris Lew <quic_clew@quicinc.com>
Link: https://lore.kernel.org/r/20240529-hwspinlock-bust-v3-2-c8b924ffa5a2@quicinc.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

When a remoteproc crashes or goes down unexpectedly this can result in
a state where locks held by the remoteproc will remain locked possibly
resulting in deadlock. This new API hwspin_lock_bust() allows
hwspinlock implementers to define a bust operation for freeing previously
acquired hwspinlocks after verifying ownership of the acquired lock.

Signed-off-by: Richard Maina <quic_rmaina@quicinc.com>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Chris Lew <quic_clew@quicinc.com>
Link: https://lore.kernel.org/r/20240529-hwspinlock-bust-v3-1-c8b924ffa5a2@quicinc.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

For loops with multiple initializers and increments are hard to read
and reason about, simplify this by using the looping index to index
into the hwspinlock array.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20240208165114.63148-4-afd@ti.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

This will unregister the HW spinlock on module exit automatically for us,
currently we manually unregister which can be error-prone if not done in
the right order. This also allows us to remove the remove callback.
Do that here.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20240208165114.63148-3-afd@ti.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

This disables runtime PM on module exit automatically for us, currently
we manually disable runtime PM which can be error-prone if not done
in the right order or missed in some exit path. This also allows us
to simplify the probe exit path and remove callbacks. Do that here.

While here, as we can now return right after registering our hwspinlock,
simply return directly and remove the extra debug message.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20240208165114.63148-2-afd@ti.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

We do not use the OF node anymore, nor does it matter how
we got to probe, so remove the check for of_node.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20240208165114.63148-1-afd@ti.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>