From: Tomi Valkeinen <tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>
When we have an ATR, and another ATR as a subdevice of the first ATR,
we get lockdep warnings for the i2c_atr.lock and
i2c_atr_chan.orig_addrs_lock. This is because lockdep uses a static key
for the locks, and doesn't see the locks of the separate ATR instances
as separate.
Fix this by generating a dynamic lock key per lock instance.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>
---
drivers/i2c/i2c-atr.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c
index ef5adafa9bf4..9bdbd94b5054 100644
--- a/drivers/i2c/i2c-atr.c
+++ b/drivers/i2c/i2c-atr.c
@@ -54,6 +54,7 @@ struct i2c_atr_chan {
/* Lock orig_addrs during xfer */
struct mutex orig_addrs_lock;
+ struct lock_class_key orig_addrs_lock_key;
u16 *orig_addrs;
unsigned int orig_addrs_size;
};
@@ -84,6 +85,7 @@ struct i2c_atr {
struct i2c_algorithm algo;
/* lock for the I2C bus segment (see struct i2c_lock_operations) */
struct mutex lock;
+ struct lock_class_key lock_key;
int max_adapters;
size_t num_aliases;
@@ -505,7 +507,10 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev,
if (!atr)
return ERR_PTR(-ENOMEM);
+ lockdep_register_key(&atr->lock_key);
mutex_init(&atr->lock);
+ lockdep_set_class(&atr->lock, &atr->lock_key);
+
spin_lock_init(&atr->alias_mask_lock);
atr->parent = parent;
@@ -535,6 +540,7 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev,
kfree(atr->aliases);
err_destroy_mutex:
mutex_destroy(&atr->lock);
+ lockdep_unregister_key(&atr->lock_key);
kfree(atr);
return ERR_PTR(ret);
@@ -552,6 +558,7 @@ void i2c_atr_delete(struct i2c_atr *atr)
bitmap_free(atr->alias_use_mask);
kfree(atr->aliases);
mutex_destroy(&atr->lock);
+ lockdep_unregister_key(&atr->lock_key);
kfree(atr);
}
EXPORT_SYMBOL_NS_GPL(i2c_atr_delete, I2C_ATR);
@@ -586,7 +593,9 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id,
chan->atr = atr;
chan->chan_id = chan_id;
INIT_LIST_HEAD(&chan->alias_list);
+ lockdep_register_key(&chan->orig_addrs_lock_key);
mutex_init(&chan->orig_addrs_lock);
+ lockdep_set_class(&chan->orig_addrs_lock, &chan->orig_addrs_lock_key);
snprintf(chan->adap.name, sizeof(chan->adap.name), "i2c-%d-atr-%d",
i2c_adapter_id(parent), chan_id);
@@ -646,6 +655,7 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id,
err_fwnode_put:
fwnode_handle_put(dev_fwnode(&chan->adap.dev));
mutex_destroy(&chan->orig_addrs_lock);
+ lockdep_unregister_key(&chan->orig_addrs_lock_key);
kfree(chan);
return ret;
}
@@ -679,6 +689,7 @@ void i2c_atr_del_adapter(struct i2c_atr *atr, u32 chan_id)
fwnode_handle_put(fwnode);
mutex_destroy(&chan->orig_addrs_lock);
+ lockdep_unregister_key(&chan->orig_addrs_lock_key);
kfree(chan->orig_addrs);
kfree(chan);
}
--
2.43.0
