-
Daniel Kurtz authored
The i915 is only able to generate a STOP cycle (i.e. finalize an i2c transaction) during a DATA or WAIT phase. In other words, the controller rejects a STOP requested as part of the first transaction in a sequence. Thus, for the first transaction we must always use a WAIT cycle, detect when the device has finished (and is in a WAIT phase), and then either start the next transaction, or, if there are no more transactions, generate a STOP cycle. Note: Theoretically, the last transaction of a multi-transaction sequence could initiate a STOP cycle. However, this slight optimization is left for another patch. We return -ETIMEDOUT if the hardware doesn't deactivate after the STOP cycle. Signed-off-by:
Daniel Kurtz <djkurtz@chromium.org> [danvet: added comment to the code that gmbus can't generate STOP on the very first cycle.] Signed-off-by:
Daniel Vetter <daniel.vetter@ffwll.ch>
72d66afd