Provide the required plumbing for the stm32 keyboard scan code so that
the message layer will pick up keyboard scans.
The design is as follows:
- When a change in keyboard state is detected, the keyboard matrix
scanning code will call the board-specific board_keyboard_scan_ready()
function to interrupt the AP.
- The AP will initiate a CMDC_KEY_STATE transaction over SPI or I2C
- The SPI or I2C driver will call message_process_cmd() to process the
command
- This in turn will call keyboard_get_scan() to get the latest scan data
For SPI:
- The AP will initiate an 20-byte (or longer) SPI transaction
- The EC will see the command, and provide the keyboard state in response,
with the response being part of the same transaction
For I2C:
- The AP will initiate a 1-byte write to set the EC mode.
- The AP will then initiate an 18-byte read, and the EC will send the
message including keyboard state
BUG=chromium-os:28925
TEST=build on daisy and discovery; run on daisy
Change-Id: I905ef9d567e43d85fb851052f67586eff58e1167
Signed-off-by: Simon Glass <sjg@chromium.org>
Whatever means is used to talk to the AP there is no justifcation for
putting message processing directly in drivers. Create a suitable
header file to define the interface, and provide a processing function
which can provide responses to incoming messages.
BUG=chromium-os:28925
TEST=build on daisy and discovery; run on daisy
Change-Id: If09ea3e30d42d8c5f226dc4421d4895adc54f937
Signed-off-by: Simon Glass <sjg@chromium.org>
