On Sat, 2014-12-20 at 00:25 +0200, Daniel Baluta wrote: > On Sat, Dec 20, 2014 at 12:16 AM, Hartmut Knaack <knaack.h@xxxxxx> wrote: > > Daniel Baluta schrieb am 18.12.2014 um 18:16: > >> When using ACPI, if acpi_match_device fails then chipset enum will be > >> uninitialized and &ak_def_array[chipset] will point to some bad address. > >> I am missing something. You are enumerated over i2c device, which was created from ACPI PNP resource. There is a valid handle or and the device has an ACPI companion at the least. If this failing, I have to check the code for acpi i2c. Can you check why this check failed? We may have bug in i2c handling. Thanks, Srinivas > >> This fixes the following compilation warning: > >> > >> drivers/iio/magnetometer/ak8975.c: In function ‘ak8975_probe’: > >> drivers/iio/magnetometer/ak8975.c:788:14: warning: ‘chipset’ may be used > >> uninitialized in this function [-Wmaybe-uninitialized] > >> data->def =ak_def_array[chipset]; > >> > >> Reported-by: Octavian Purdila <octavian.purdila@xxxxxxxxx> > >> Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxxxx> > >> --- > >> This is a RFC because while I'm pretty sure that chipset should be initialized > >> with AK_MAX_TYPE in ak8975_match_acpi_device, I am not sure if we can live with > >> a NULL return value of ak8975_match_acpi_device. Current implementation ignores > >> return value of ak8975_match_acpi_device. > > This seems to be the actual problem: these _match_acpi_device functions return > > NULL on failure, and this should be checked for. > > Ok, so this would acceptable? > > diff --git a/drivers/iio/magnetometer/ak8975.c > b/drivers/iio/magnetometer/ak8975.c > index 0d10a4b..68d99e9 100644 > --- a/drivers/iio/magnetometer/ak8975.c > +++ b/drivers/iio/magnetometer/ak8975.c > @@ -776,8 +776,9 @@ static int ak8975_probe(struct i2c_client *client, > name = id->name; > } else if (ACPI_HANDLE(&client->dev)) > name = ak8975_match_acpi_device(&client->dev, &chipset); > - else > - return -ENOSYS; > + > + if (!name) > + return -ENODEV; > > > I still have some doubts about return code in case of error. > > For ak8975 we use -ENOSYS, but for kxcjk-1013 we use -ENODEV. > > I will send a patch after we clear this out. > > thanks, > Daniel. -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
