[ Upstream commit 27ff8187f13ecfec8a26fb1928e906f46f326cc5 ]

Fix sparse warning:
drivers/opp/of.c:924 _opp_add_static_v2() warn: passing zero to 'ERR_PTR'

For duplicate OPPs 'ret' be set to zero.

Fixes: deac8703da5f ("PM / OPP: _of_add_opp_table_v2(): increment count only if OPP is added")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 020d86fc0df8b865f6dc168d88a7c2dccabd0a9e ]

The 'required-opps' property is considered optional, hence remove
the pr_err() in of_parse_required_opp() when we find the property is
missing.
While at it, also fix the return value of
of_get_required_opp_performance_state() when of_parse_required_opp()
fails, return a -ENODEV instead of the -EINVAL.

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 335ffab3ef864539e814b9a2903b0ae420c1c067 ]

This WARN can be triggered per-core and the stack trace is not useful.
Replace it with plain dev_err(). Fix a comment while at it.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 6544abc520f0fff701e9da382110dc29676c683a ]

Currently, when using _of_add_opp_table_v2 parsed_static_opps is
increased and this value is used in _opp_remove_all_static() to
check if there are static opp entries that need to be freed.
Unfortunately this does not happen when using _of_add_opp_table_v1(),
which leads to warnings.

This patch increases parsed_static_opps in _of_add_opp_table_v1() in a
similar way as in _of_add_opp_table_v2().

Fixes: 03758d60265c ("opp: Replace list_kref with a local counter")
Cc: v5.6+ <stable@vger.kernel.org> # v5.6+
Signed-off-by: Walter Lozano <walter.lozano@collabora.com>
[ Viresh: Do the operation with lock held and set the value to 1 instead
	  of incrementing it ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 03758d60265c773e1d06d436b99ee338f2ac55d6 ]

A kref or refcount isn't the right tool to be used here for counting
number of devices that are sharing the static OPPs created for the OPP
table. For example, we are reinitializing the kref again, after it
reaches a value of 0 and frees the resources, if the static OPPs get
added for the same OPP table structure (as the OPP table structure was
never freed). That is messy and very unclear.

This patch makes parsed_static_opps an unsigned integer and uses it to
count the number of users of the static OPPs. The increment and
decrement to parsed_static_opps is done under opp_table->lock now to
make sure no races are possible if the OPP table is getting added and
removed in parallel (which doesn't happen in practice, but can in
theory).

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit ba0033192145cbd4e70ef64552958b13d597eb9e ]

The static OPPs aren't getting freed properly, if errors occur while
adding them. Fix that by calling _put_opp_list_kref() and putting their
reference on failures.

Fixes: 11e1a1648298 ("opp: Don't decrement uninitialized list_kref")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

The list_kref reaches a count of 0 when all the static OPPs are removed,
for example when dev_pm_opp_of_cpumask_remove_table() is called, though
the actual OPP table may not get freed as it may still be referenced by
other parts of the kernel, like from a call to
dev_pm_opp_set_supported_hw(). And if we call
dev_pm_opp_of_cpumask_add_table() again at this point, we must
reinitialize the list_kref otherwise the kernel will hit a WARN() in
kref infrastructure for incrementing a kref with value 0.

Fixes: 11e1a1648298 ("opp: Don't decrement uninitialized list_kref")
Reported-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

_find_opp_of_np() doesn't traverse the list of OPP tables but instead
just the entries within an OPP table and so only requires to lock the
OPP table itself.

The lockdep_assert_held() was added there by mistake and isn't really
required.

Fixes: 5d6d106fa455 ("OPP: Populate required opp tables from "required-opps" property")
Cc: v5.0+ <stable@vger.kernel.org> # v5.0+
Reported-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

With property "opp-supported-hw" introduced, the OPP table
in DT could be a large OPP table and ONLY a subset of OPPs
are available, based on the version of the hardware running
on. That introduces restriction of using "opp-suspend"
property to define the suspend OPP, as we are NOT sure if the
OPP containing "opp-suspend" property is available for the
hardware running on, and the of opp core does NOT allow multiple
suspend OPPs defined in DT OPP table.

To eliminate this restrition, make of opp core allow multiple
suspend OPPs defined in DT, and pick the OPP with highest rate
and with "opp-suspend" property present to be suspend OPP, it
can speed up the suspend/resume process.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

The list_kref was added for static OPPs and to track their users. The
kref is initialized while the static OPPs are added, but removed
unconditionally even if the static OPPs were never added. This causes
refcount mismatch warnings currently.

Fix that by always initializing the kref when the OPP table is first
initialized. The refcount is later incremented only for the second user
onwards.

Fixes: d0e8ae6c26da ("OPP: Create separate kref for static OPPs list")
Reported-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>