diff options
| author | Daniel Mack <daniel@zonque.org> | 2023-10-18 12:46:13 +0300 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2023-10-28 15:47:49 +0300 |
| commit | 53801d2e762a611d972e91d151df56c3412ca5cf (patch) | |
| tree | 31d84bdd47d81cd1ea2cac81dd01ef0a614960dd /drivers/i2c | |
| parent | 702c0dd7bcf169c44cb4a67447532861877c2744 (diff) | |
| download | linux-53801d2e762a611d972e91d151df56c3412ca5cf.tar.xz | |
i2c: core: fix lockdep warning for sparsely nested adapter chain
When adapters are chained in a sparse manner (with intermediate MFD devices,
for instance) the code currently fails to use the correct subclass for
the adapter's bus_lock which leads to false-positive lockdep warnings.
Fix this by walking the entire pedigree of the device and count all
adapters along the way instead of just checking the immediate parent.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/i2c-core-base.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 7f30bcceebae..eac90a3cf61a 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -1194,9 +1194,11 @@ static void i2c_adapter_dev_release(struct device *dev) unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) { unsigned int depth = 0; + struct device *parent; - while ((adapter = i2c_parent_is_i2c_adapter(adapter))) - depth++; + for (parent = adapter->dev.parent; parent; parent = parent->parent) + if (parent->type == &i2c_adapter_type) + depth++; WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES, "adapter depth exceeds lockdep subclass limit\n"); |