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authorDavid Brownell <dbrownell@users.sourceforge.net>2008-10-14 17:30:05 +0200
committerJean Delvare <khali@mahadeva.delvare>2008-10-14 17:30:05 +0200
commit1d0b19c9a0612c653d1a0df267ba159089f6d139 (patch)
tree406b09500a13eaf91f2f8a925e76db40f450a712
parent7c15fd1249658e203b2ac8661e48da6c2102e563 (diff)
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i2c: Guard against oopses from bad init sequences
Guard I2C against oopsing because of init sequence problems, by verifying that i2c_init() has been called before calling any routines that rely on that initialization. This specific test just requires that bus_register(&i2c_bus_type) was called. Examples of this kind of oopsing come from subystems and drivers which register I2C drivers in their subsys_initcall code but which are statically linked before I2C by drivers/Makefile. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
-rw-r--r--drivers/i2c/i2c-core.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index b346a687ab59..a96e1bf27649 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -437,6 +437,10 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
{
int res = 0, dummy;
+ /* Can't register until after driver model init */
+ if (unlikely(WARN_ON(!i2c_bus_type.p)))
+ return -EAGAIN;
+
mutex_init(&adap->bus_lock);
mutex_init(&adap->clist_lock);
INIT_LIST_HEAD(&adap->clients);
@@ -696,6 +700,10 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
{
int res;
+ /* Can't register until after driver model init */
+ if (unlikely(WARN_ON(!i2c_bus_type.p)))
+ return -EAGAIN;
+
/* new style driver methods can't mix with legacy ones */
if (is_newstyle_driver(driver)) {
if (driver->attach_adapter || driver->detach_adapter