Transactions from RTIO should result in single calls to i2c_transfer.
This corrects the default handler to first count the number of
submissions in the transaction, allocate on the stack, and then copy
over each submission to an equivalent i2c_msg.
It also cleans up the helper functions to be infallible, taking only the
submission and msg to copy to.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
TXRX is meant specifically to handle a full duplex bus like SPI, I2C is
half duplex meaning only read or write can be performed at once.
Drop TXRX as a supported operation code for the default I2C submission
path.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
Use the RTIO work queue to fake the i2c submit calls for drivers which
haven't yet implemented the API. Applications can change the size of
the work queue pool depending on how much traffic they have on the buses.
Signed-off-by: Yuval Peress <peress@google.com>
