i2c: piix4: Fix SB800 locking

We need a single mutex for all 4 shared SMBus ports on the SB800. A
per-port mutex doesn't protect us from concurrent access.

In theory the mutex should be per PCI device, however in practice we
know that there's only ever a single instance of the device in a given
system so we can use a global.

Also take the mutex during initialization, as first port may be already
in use when second port is initialized.

Signed-off-by: Jean Delvare <[email protected]>
Tested-by: Christian Fetzer <[email protected]>
Reviewed-by: Mika Westerberg <[email protected]>
[wsa: made mutex static]
Signed-off-by: Wolfram Sang <[email protected]>

0 files changed, 0 insertions, 0 deletions