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| author | Viresh Kumar <viresh.kumar@linaro.org> | 2018-09-07 06:31:54 +0300 |
|---|---|---|
| committer | Viresh Kumar <viresh.kumar@linaro.org> | 2018-10-01 12:30:31 +0300 |
| commit | 283d55e68d8a0f302057f57dcbd4d2e000c2ac85 (patch) | |
| tree | bb1114ed98b8416d6926f8f6a82c1017899896f4 /drivers/opp/core.c | |
| parent | cdd6ed90cdb6c2fd982909501f0a109274147fb4 (diff) | |
| download | linux-283d55e68d8a0f302057f57dcbd4d2e000c2ac85.tar.xz | |
OPP: Prevent creating multiple OPP tables for devices sharing OPP nodes
When two or more devices are sharing their clock and voltage rails, they
share the same OPP table. But there are some corner cases where the OPP
core incorrectly creates separate OPP tables for them.
For example, CPU 0 and 1 share clock/voltage rails. The platform
specific code calls dev_pm_opp_set_regulators() for CPU0 and the OPP
core creates an OPP table for it (the individual OPPs aren't initialized
as of now). The same is repeated for CPU1 then. Because
_opp_get_opp_table() doesn't compare DT node pointers currently, it
fails to find the link between CPU0 and CPU1 and so creates a new OPP
table.
Fix this by calling _managed_opp() from _opp_get_opp_table().
_managed_opp() gain an additional argument (index) to get the right node
pointer. This resulted in simplifying code in _of_add_opp_table_v2() as
well.
Tested-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Diffstat (limited to 'drivers/opp/core.c')
| -rw-r--r-- | drivers/opp/core.c | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/drivers/opp/core.c b/drivers/opp/core.c index d3e33fd32694..cdf918aaac34 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -759,8 +759,8 @@ static void _remove_opp_dev(struct opp_device *opp_dev, kfree(opp_dev); } -struct opp_device *_add_opp_dev(const struct device *dev, - struct opp_table *opp_table) +static struct opp_device *_add_opp_dev_unlocked(const struct device *dev, + struct opp_table *opp_table) { struct opp_device *opp_dev; int ret; @@ -772,7 +772,6 @@ struct opp_device *_add_opp_dev(const struct device *dev, /* Initialize opp-dev */ opp_dev->dev = dev; - mutex_lock(&opp_table->lock); list_add(&opp_dev->node, &opp_table->dev_list); /* Create debugfs entries for the opp_table */ @@ -780,6 +779,17 @@ struct opp_device *_add_opp_dev(const struct device *dev, if (ret) dev_err(dev, "%s: Failed to register opp debugfs (%d)\n", __func__, ret); + + return opp_dev; +} + +struct opp_device *_add_opp_dev(const struct device *dev, + struct opp_table *opp_table) +{ + struct opp_device *opp_dev; + + mutex_lock(&opp_table->lock); + opp_dev = _add_opp_dev_unlocked(dev, opp_table); mutex_unlock(&opp_table->lock); return opp_dev; @@ -844,6 +854,15 @@ static struct opp_table *_opp_get_opp_table(struct device *dev, int index) if (!IS_ERR(opp_table)) goto unlock; + opp_table = _managed_opp(dev, index); + if (opp_table) { + if (!_add_opp_dev_unlocked(dev, opp_table)) { + dev_pm_opp_put_opp_table(opp_table); + opp_table = NULL; + } + goto unlock; + } + opp_table = _allocate_opp_table(dev, index); unlock: |