zaurus bluetooth regression

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It seems this commit

commit 7a56aa45982bb87bfca98a2832b5ae782c03364a

...

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...is responsible for my bluetooth problems on zaurus -- at least
bisect pointed to it, ?as I use 16C950-based bluetooth card, it seems
very logical. I'll try 2.6.37-rc8 with that patch reverted...

And yes, 37-rc8 with that reverted results in working bluetooth, so
yrs, that patch is responsible.

could you tell, what kind of problem you're encountering and if you
could tell, which flag UART_CAP_EFR or UART_CAP_SLEEP causes the
problem?

Bluetooth will not work with 'tx command timeout', details should be
in bugzilla.

CAP_EFR seems to cause the problem.

Aside from sleep functions the only impact CAP_EFR makes is enabling
automatic CTS flow control. Below the cite from 16C950 data sheet:

"EFR[7]: Enable automatic CTS flow control.
logic 0 ?   CTS flow control is disabled (default).
logic 1 ?   CTS flow control is enabled in Enhanced mode
(i.e. EFR[4] = 1), where the data transmission is
prevented  whenever  the  CTS#  pin  is  held
inactive high. 650 and 950-mode drivers should
use  this  bit  to  enable  CTS  flow  control.    750
mode drivers should use MCR[5].

When automatic CTS flow control is enabled and the CTS#
input becomes active, the UART will disable transmission
as soon as any current character transmission is complete.
Transmission   is   resumed   whenever   the   CTS#   input
becomes inactive. "

I've tested with such an UART and transmitted some chunk of data with
and without RTS/CTS flow control enabled at 460800 b/s. The test
showed that in enabled state all data was transmitted correctly.
Without RTS/CTS flow control enabled there was massive data loss, as
expected. So the flow control function seems to work correctly.

Regards,
Yegor