70df9ebbd8
When using DT configurations, the id pointer might turn out to
be NULL. Then the driver encounters NULL pointer access:
Unable to handle kernel read from unreadable memory at vaddr 00000018
[...]
PC is at ina2xx_probe+0x114/0x200
LR is at ina2xx_probe+0x10c/0x200
[...]
Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
The reason is that i2c core returns the id pointer by matching
id_table with client->name, while the client->name is actually
using the name from the first string in the DT compatible list,
not the best one. So i2c core would fail to match the id_table
if the best matched compatible string isn't the first one, and
then would return a NULL id pointer.
This probably should be fixed in i2c core. But it doesn't hurt
to make the driver robust. So this patch fixes it by using the
"chip" that's added to unify both DT and non-DT configurations.
Additionally, since id pointer could be null, so as id->name:
ina2xx 10-0047: power monitor (null) (Rshunt = 1000 uOhm)
ina2xx 10-0048: power monitor (null) (Rshunt = 10000 uOhm)
So this patch also fixes NULL name pointer, using client->name
to play safe and to align with hwmon->name.
Fixes: bd0ddd4d08 ("hwmon: (ina2xx) Add OF device ID table")
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.