mainlining shenanigans

Bryan O'Donoghue 12927835d2 greybus: loopback: Add asynchronous bi-directional support ... A particular ask from the firmware people for some time now has been the ability to drive multiple outstanding bi-directional operations from loopback to loopback Interfaces. This patch implments that change. The approach taken is to make a call to gb_operation_send() and have loopback capture the completion callback itself, with a parallel timer to timeout completion callbacks that take too long. The calling thread will issue each gb_operation_send() as fast as it can within the constraints of thread-safety. In order to support this addition the following new sysfs entries are created on a per-connection basis. - async Zero indicates loopback should use the traditional synchronous model i.e. gb_operation_request_send_sync(). Non-zero indicates loopback should use the new asynchronous model i.e. gb_operation_send() - requests_completed This value indicates the number of requests successfully completed. - requests_timedout This value indicates the number of requests which timed out. - timeout The number of microseconds to give an individual asynchronous request before timing that request out. - timeout_min Read-only attribute informs user-space of the minimum allowed timeout. - timeout_max Read-only attribute informs user-space of the maximum allowed timeout. Note requests_completed + requests_timedout should always equal iteration_max, once iteration_count == iteration_max. Also, at this time we support either synchronous or asynchronous operations in one set of transactions. Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>		2015-12-07 14:32:20 -05:00
drivers/staging/greybus	greybus: loopback: Add asynchronous bi-directional support	2015-12-07 14:32:20 -05:00