From 26680ee279ca7e404275eab2c683b5324afb396a Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Thu, 29 Jan 2015 22:45:09 +0100 Subject: i2c: clarify comments about the dev_released completion There was quite some confusion why this completion is there and if it is still necessary. Sadly, it is. However, let's improve the comments and share what we rediscovered. Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 72d53e40ebab..4764a1fa0b56 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1666,11 +1666,15 @@ void i2c_del_adapter(struct i2c_adapter *adap) /* device name is gone after device_unregister */ dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); - /* clean up the sysfs representation */ + /* wait until all references to the device are gone + * + * FIXME: This is old code and should ideally be replaced by an + * alternative which results in decoupling the lifetime of the struct + * device from the i2c_adapter, like spi or netdev do. Any solution + * should be throughly tested with DEBUG_KOBJECT_RELEASE enabled! + */ init_completion(&adap->dev_released); device_unregister(&adap->dev); - - /* wait for sysfs to drop all references */ wait_for_completion(&adap->dev_released); /* free bus id */ -- cgit v1.2.1