On Tue, 30 Mar 2010 11:42:37 +0200, Wolfram Sang wrote: > After discovering that a lot of i2c-drivers leave the pointer to their > clientdata dangling, it was decided to let the core handle this issue. > It is assumed that the core may access the private data after remove() > as there are no guarantees for the lifetime of such pointers anyhow (see > thread starting at http://lkml.org/lkml/2010/3/21/68) > > Signed-off-by: Wolfram Sang <w.sang@xxxxxxxxxxxxxx> > Cc: Jean Delvare <khali@xxxxxxxxxxxx> > --- > > Documentation/i2c/writing-clients | 5 +++++ > drivers/i2c/i2c-core.c | 8 ++++++-- > 2 files changed, 11 insertions(+), 2 deletions(-) > > diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients > index 3219ee0..5ebf5af 100644 > --- a/Documentation/i2c/writing-clients > +++ b/Documentation/i2c/writing-clients > @@ -74,6 +74,11 @@ structure at all. You should use this to keep device-specific data. > /* retrieve the value */ > void *i2c_get_clientdata(const struct i2c_client *client); > > +Note that starting with kernel 2.6.34, you don't have to set the `data' field > +to NULL in remove() or if probe() failed anymore. The i2c-core does this > +automatically on these occasions. Those are also the only times the core will > +touch this field. > + > > Accessing the client > ==================== > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > index 3202a86..b9306b1 100644 > --- a/drivers/i2c/i2c-core.c > +++ b/drivers/i2c/i2c-core.c > @@ -117,8 +117,10 @@ static int i2c_device_probe(struct device *dev) > dev_dbg(dev, "probe\n"); > > status = driver->probe(client, i2c_match_id(driver->id_table, client)); > - if (status) > + if (status) { > client->driver = NULL; > + i2c_set_clientdata(client, NULL); > + } > return status; > } > > @@ -139,8 +141,10 @@ static int i2c_device_remove(struct device *dev) > dev->driver = NULL; > status = 0; > } > - if (status == 0) > + if (status == 0) { > client->driver = NULL; > + i2c_set_clientdata(client, NULL); > + } > return status; > } > Applied, thanks. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
