hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
authorGuenter Roeck <linux@roeck-us.net>
Thu, 4 Apr 2019 18:22:42 +0000 (11:22 -0700)
committerGuenter Roeck <linux@roeck-us.net>
Tue, 16 Apr 2019 00:19:53 +0000 (17:19 -0700)
commit8c0826756744c0ac1df600a5e4cca1a341b13101
tree2798eb6a92ce30f42c9517cc1d36f5fd2f74e0f9
parent755a9b0f8aaa5639ba5671ca50080852babb89ce
hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses

Super-IO accesses may fail on a system with no or unmapped LPC bus.

Also, other drivers may attempt to access the LPC bus at the same time,
resulting in undefined behavior.

Use request_muxed_region() to ensure that IO access on the requested
address space is supported, and to ensure that access by multiple drivers
is synchronized.

Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: John Garry <john.garry@huawei.com>
Cc: John Garry <john.garry@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
drivers/hwmon/smsc47b397.c