tree 60aada7f006fd73797b5c566d704e2b0ed5b728f
parent ca82e6161af7a453b512f35dd695a98084a1d7cf
author Jes Klinke <jbk@google.com> 1645574409 -0800
committer Julius Werner <jwerner@chromium.org> 1647381987 +0000

i2c: Add configurable I2C transfer timeout

This patch introduces CONFIG_I2C_TRANSFER_TIMEOUT_US,
which controls how long to wait for an I2C devices to
produce/accept all the data bytes in a single transfer.
(The device can delay transfer by stretching the clock of
the ack bit.)

The default value of this new setting is 500ms.  Existing
code had timeouts anywhere from tens of milliseconds to a
full second beween various drivers.  Drivers can still have
their own shorter timeouts for setup/communication with the
I2C host controller (as opposed to transactions with I2C
devices on the bus.)

In general, the timeout is not meant to be reached except in
situations where there is already serious problem with the
boot, and serves to make sure that some useful diagnostic
output is produced on the console.

Change-Id: I6423122f32aad1dbcee0bfe240cdaa8cb512791f
Signed-off-by: Jes B. Klinke <jbk@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/62278
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>