From 6ea23039cb1cc7c379eb5fba0ed2c53291e9bea7 Mon Sep 17 00:00:00 2001 From: Jiri Kosina Date: Sun, 10 Dec 2006 21:21:30 +0100 Subject: [PATCH] i2c: Add support for nested i2c bus locking This patch adds the 'level' field into the i2c_adapter structure, which is used to represent the 'logical' level of nesting for the purposes of lockdep. This field is then used in the i2c_transfer() function, to acquire the per-adapter bus_lock with correct nesting level. Signed-off-by: Jiri Kosina Signed-off-by: Jean Delvare --- drivers/i2c/i2c-core.c | 2 +- include/linux/i2c.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 7ca81f42d14b..79eaa12474dd 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -603,7 +603,7 @@ int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg *msgs, int num) } #endif - mutex_lock(&adap->bus_lock); + mutex_lock_nested(&adap->bus_lock, adap->level); ret = adap->algo->master_xfer(adap,msgs,num); mutex_unlock(&adap->bus_lock); diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 9b5d04768c2c..08df4169b411 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -216,6 +216,7 @@ struct i2c_adapter { int (*client_unregister)(struct i2c_client *); /* data fields that are valid for all devices */ + u8 level; /* nesting level for lockdep */ struct mutex bus_lock; struct mutex clist_lock; -- 2.20.1