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Commit b9562545ef ("bcma: complete workaround for BCMA43224 and
BCM4313") introduced the wrong masks for setting the chip control
registers - the "mask" parameter is inverse.
It should be the mask of bits *not* changed, which is admittedly a bit
non-intuitive.
The incorrect mask not only causes the driver to not work correctly on
the chips affected (eg the BCM43224 on the Macbook Air 4,2) but the
state persists over a soft reset, causing the next boot to not
necessarily see the device correctly.
Reported-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Arend Van Spriel <arend@broadcom.com>
Cc: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Cc: Brett Rudley <brudley@broadcom.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Broadcom introduced new bus as replacement for older SSB. It is based on AMBA, however from programming point of view there is nothing AMBA specific we use. Standard AMBA drivers are platform specific, have hardcoded addresses and use AMBA standard fields like CID and PID. In case of Broadcom's cards every device consists of: 1) Broadcom specific AMBA device. It is put on AMBA bus, but can not be treated as standard AMBA device. Reading it's CID or PID can cause machine lockup. 2) AMBA standard devices called ports or wrappers. They have CIDs (AMBA_CID) and PIDs (0x103BB369), but we do not use that info for anything. One of that devices is used for managing Broadcom specific core. Addresses of AMBA devices are not hardcoded in driver and have to be read from EPROM. In this situation we decided to introduce separated bus. It can contain up to 16 devices identified by Broadcom specific fields: manufacturer, id, revision and class.