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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/devicetree/bindings/mfd/cros-ec.txt
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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+ChromeOS Embedded Controller
+
+Google's ChromeOS EC is a Cortex-M device which talks to the AP and
+implements various function such as keyboard and battery charging.
+
+The EC can be connect through various means (I2C, SPI, LPC) and the
+compatible string used depends on the interface. Each connection method has
+its own driver which connects to the top level interface-agnostic EC driver.
+Other Linux driver (such as cros-ec-keyb for the matrix keyboard) connect to
+the top-level driver.
+
+Required properties (I2C):
+- compatible: "google,cros-ec-i2c"
+- reg: I2C slave address
+
+Required properties (SPI):
+- compatible: "google,cros-ec-spi"
+- reg: SPI chip select
+
+Optional properties (SPI):
+- google,cros-ec-spi-msg-delay: Some implementations of the EC require some
+ additional processing time in order to accept new transactions. If the delay
+ between transactions is not long enough the EC may not be able to respond
+ properly to subsequent transactions and cause them to hang. This property
+ specifies the delay, in usecs, introduced between transactions to account
+ for the time required by the EC to get back into a state in which new data
+ can be accepted.
+
+Required properties (LPC):
+- compatible: "google,cros-ec-lpc"
+- reg: List of (IO address, size) pairs defining the interface uses
+
+
+Example for I2C:
+
+i2c@12CA0000 {
+ cros-ec@1e {
+ reg = <0x1e>;
+ compatible = "google,cros-ec-i2c";
+ interrupts = <14 0>;
+ interrupt-parent = <&wakeup_eint>;
+ wakeup-source;
+ };
+
+
+Example for SPI:
+
+spi@131b0000 {
+ ec@0 {
+ compatible = "google,cros-ec-spi";
+ reg = <0x0>;
+ interrupts = <14 0>;
+ interrupt-parent = <&wakeup_eint>;
+ wakeup-source;
+ spi-max-frequency = <5000000>;
+ controller-data {
+ cs-gpio = <&gpf0 3 4 3 0>;
+ samsung,spi-cs;
+ samsung,spi-feedback-delay = <2>;
+ };
+ };
+};
+
+
+Example for LPC is not supplied as it is not yet implemented.