Re: [PATCH 0/2] fixes for adt7410

[Sascha Hauer <s.hauer@pengutronix.de>]

On Sun, Jul 15, 2012 at 11:11:52PM +0200, Lars-Peter Clausen wrote:
> On 07/15/2012 10:40 PM, Hartmut Knaack wrote:
> > This patchset makes the ADT7410 usable. Main reason was the following error when trying to register one of these devices:
> > [  180.945561] BUG: unable to handle kernel NULL pointer dereference at   (null)
> > [  180.945592] IP: [<f84b1e80>] iio_device_register_eventset+0x380/0x3a0 [industrialio]
> > This happens, since in industrialio-events.c __iio_add_event_config_attrs (which does a INIT_LIST_HEAD) is not called, if the channels attribute of the device is not set. As a result, list_for_each_entry causes those NULL pointer dereference problems. So, before trying to access those list elements, we check for their existence (also in unregister functions).
> > Now the adt7410.c ended in some complex changes - my apologies for this:
> > 
> >   * check for exact values provided through sysfs, otherwise output a verbose error/usage message for: sample mode, resolution, event mode
> >   * adt7410_show_id: I don't see a point in masking out some LSBs, if they get shifted to oblivion, anyway -> no more need for ADT7410_MANUFACTORY_ID_MASK
> >   * adt7410_convert_temperature: in 13 bit mode, the driver assumed the data to be stored in bits 0-12, but according to the data sheet, it is stored in bits 3-15. Temperature readings were always around 200(°C), while real temperature was something around 20(°C). Simple fix: mask out bits 0-2 in 13 bit mode and use the 16 bit routines from that point on.
> >   * adt7410_set_t_bound: handle float values provided through sysfs properly. Also, simplify treatment of 13 bit values by masking out bits 0-2.
> >   * adt7410_probe, adt7410_remove: fix another possible NULL pointer dereference issue, in case no platform data is provided. Sync chip->config with the config register
> 
> Hi,
> 
> Sascha Hauer posted a couple of patches a while ago which seem to fix a
> similar set of issues.
> 
> See: http://www.spinics.net/lists/linux-iio/msg05947.html and
> http://www.spinics.net/lists/linux-iio/msg05955.html

Indeed, most if not all of the mentioned issues should be fixed already
with these patches.

Sascha


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