mfd: Add ChromeOS EC I2C driver

This uses an I2C bus to talk to the ChromeOS EC. The protocol
is defined by the EC and is fairly simple, with a length byte,
checksum, command byte and version byte (to permit easy creation
of new commands).

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index a8bafb560196..4e54b5b01295 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -29,6 +29,16 @@ config MFD_CROS_EC
           You also ned to enable the driver for the bus you are using. The
           protocol for talking to the EC is defined by the bus driver.
 
+config MFD_CROS_EC_I2C
+        tristate "ChromeOS Embedded Controller (I2C)"
+        depends on MFD_CROS_EC && I2C
+
+        help
+          If you say Y here, you get support for talking to the ChromeOS
+          EC through an I2C bus. This uses a simple byte-level protocol with
+          a checksum. Failing accesses will be retried three times to
+          improve reliability.
+
 config MFD_88PM800
         tristate "Support Marvell 88PM800"
         depends on I2C=y && GENERIC_HARDIRQS