]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
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)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 31 May 2019 13:43:33 +0000 (06:43 -0700)
commite231d73fb6bde8a15fd359433fea831d57df6748
tree75d741312498e056c4640ae86f36fae00ebed429
parent02d5ae1cc84d9afde59ba1875c9f26e28f6a6276
hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses

[ Upstream commit 8c0826756744c0ac1df600a5e4cca1a341b13101 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/hwmon/smsc47b397.c