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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-08 00:12:21 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-08 00:12:21 +0300
commit87840a2b7e048018d18d60bdac5c09224de85370 (patch)
tree87e9f8a2317e39358f5ea189d79ef2158de5faf8 /Documentation
parent2ab704a47e0f27df758840a589aec3298dbb98dd (diff)
parent662786a5429c3a992c6f884a647ee32424822358 (diff)
downloadlinux-87840a2b7e048018d18d60bdac5c09224de85370.tar.xz
Merge branch 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: "Here is the 4.9 pull request from I2C including: - centralized error messages when registering to the core - improved lockdep annotations to prevent false positives - DT support for muxes, gates, and arbitrators - bus speeds can now be obtained from ACPI - i2c-octeon got refactored and now supports ThunderX SoCs, too - i2c-tegra and i2c-designware got a bigger bunch of updates - a couple of standard driver fixes and improvements" * 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits) i2c: axxia: disable clks in case of failure in probe i2c: octeon: thunderx: Limit register access retries i2c: uniphier-f: fix misdetection of incomplete STOP condition gpio: pca953x: variable 'id' was used twice i2c: i801: Add support for Kaby Lake PCH-H gpio: pca953x: fix an incorrect lockdep warning i2c: add a warning to i2c_adapter_depth() lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible i2c: export i2c_adapter_depth() i2c: rk3x: Fix variable 'min_total_ns' unused warning i2c: rk3x: Fix sparse warning i2c / ACPI: Do not touch an I2C device if it belongs to another adapter i2c: octeon: Fix high-level controller status check i2c: octeon: Avoid sending STOP during recovery i2c: octeon: Fix set SCL recovery function i2c: rcar: add support for r8a7796 (R-Car M3-W) i2c: imx: make bus recovery through pinctrl optional i2c: meson: add gxbb compatible string i2c: uniphier-f: set the adapter to master mode when probing i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt8
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-arb.txt35
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-gate.txt41
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-meson.txt2
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-mux.txt23
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-rcar.txt1
-rw-r--r--Documentation/devicetree/bindings/i2c/nxp,pca9541.txt29
7 files changed, 127 insertions, 12 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt b/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt
index 71191ff0e781..248a155414c2 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt
@@ -44,8 +44,7 @@ Required properties:
- our-claim-gpio: The GPIO that we use to claim the bus.
- their-claim-gpios: The GPIOs that the other sides use to claim the bus.
Note that some implementations may only support a single other master.
-- Standard I2C mux properties. See i2c-mux.txt in this directory.
-- Single I2C child bus node at reg 0. See i2c-mux.txt in this directory.
+- I2C arbitration bus node. See i2c-arb.txt in this directory.
Optional properties:
- slew-delay-us: microseconds to wait for a GPIO to go high. Default is 10 us.
@@ -63,8 +62,6 @@ Example:
i2c-arbitrator {
compatible = "i2c-arb-gpio-challenge";
- #address-cells = <1>;
- #size-cells = <0>;
i2c-parent = <&{/i2c@12CA0000}>;
@@ -74,8 +71,7 @@ Example:
wait-retry-us = <3000>;
wait-free-us = <50000>;
- i2c@0 {
- reg = <0>;
+ i2c-arb {
#address-cells = <1>;
#size-cells = <0>;
diff --git a/Documentation/devicetree/bindings/i2c/i2c-arb.txt b/Documentation/devicetree/bindings/i2c/i2c-arb.txt
new file mode 100644
index 000000000000..59abf9277bdc
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-arb.txt
@@ -0,0 +1,35 @@
+Common i2c arbitration bus properties.
+
+- i2c-arb child node
+
+Required properties for the i2c-arb child node:
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Optional properties for i2c-arb child node:
+- Child nodes conforming to i2c bus binding
+
+
+Example :
+
+ /*
+ An NXP pca9541 I2C bus master selector at address 0x74
+ with a NXP pca8574 GPIO expander attached.
+ */
+
+ arb@74 {
+ compatible = "nxp,pca9541";
+ reg = <0x74>;
+
+ i2c-arb {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ gpio@38 {
+ compatible = "nxp,pca8574";
+ reg = <0x38>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-gate.txt b/Documentation/devicetree/bindings/i2c/i2c-gate.txt
new file mode 100644
index 000000000000..1846d236e656
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-gate.txt
@@ -0,0 +1,41 @@
+An i2c gate is useful to e.g. reduce the digital noise for RF tuners connected
+to the i2c bus. Gates are similar to arbitrators in that you need to perform
+some kind of operation to access the i2c bus past the arbitrator/gate, but
+there are no competing masters to consider for gates and therefore there is
+no arbitration happening for gates.
+
+Common i2c gate properties.
+
+- i2c-gate child node
+
+Required properties for the i2c-gate child node:
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Optional properties for i2c-gate child node:
+- Child nodes conforming to i2c bus binding
+
+
+Example :
+
+ /*
+ An Invensense mpu9150 at address 0x68 featuring an on-chip Asahi
+ Kasei ak8975 compass behind a gate.
+ */
+
+ mpu9150@68 {
+ compatible = "invensense,mpu9150";
+ reg = <0x68>;
+ interrupt-parent = <&gpio1>;
+ interrupts = <18 1>;
+
+ i2c-gate {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ax8975@c {
+ compatible = "ak,ak8975";
+ reg = <0x0c>;
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-meson.txt b/Documentation/devicetree/bindings/i2c/i2c-meson.txt
index 682f9a6f766e..386357d1aab0 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-meson.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-meson.txt
@@ -1,7 +1,7 @@
Amlogic Meson I2C controller
Required properties:
- - compatible: must be "amlogic,meson6-i2c"
+ - compatible: must be "amlogic,meson6-i2c" or "amlogic,meson-gxbb-i2c"
- reg: physical address and length of the device registers
- interrupts: a single interrupt specifier
- clocks: clock for the device
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux.txt
index af84cce5cd7b..212e6779dc5c 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux.txt
@@ -2,19 +2,32 @@ Common i2c bus multiplexer/switch properties.
An i2c bus multiplexer/switch will have several child busses that are
numbered uniquely in a device dependent manner. The nodes for an i2c bus
-multiplexer/switch will have one child node for each child
-bus.
+multiplexer/switch will have one child node for each child bus.
-Required properties:
+Optional properties:
+- #address-cells = <1>;
+ This property is required is the i2c-mux child node does not exist.
+
+- #size-cells = <0>;
+ This property is required is the i2c-mux child node does not exist.
+
+- i2c-mux
+ For i2c multiplexers/switches that have child nodes that are a mixture
+ of both i2c child busses and other child nodes, the 'i2c-mux' subnode
+ can be used for populating the i2c child busses. If an 'i2c-mux'
+ subnode is present, only subnodes of this will be considered as i2c
+ child busses.
+
+Required properties for the i2c-mux child node:
- #address-cells = <1>;
- #size-cells = <0>;
-Required properties for child nodes:
+Required properties for i2c child bus nodes:
- #address-cells = <1>;
- #size-cells = <0>;
- reg : The sub-bus number.
-Optional properties for child nodes:
+Optional properties for i2c child bus nodes:
- Other properties specific to the multiplexer/switch hardware.
- Child nodes conforming to i2c bus binding
diff --git a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt
index 5f0cb502b1db..239632a0d709 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt
@@ -11,6 +11,7 @@ Required properties:
"renesas,i2c-r8a7793"
"renesas,i2c-r8a7794"
"renesas,i2c-r8a7795"
+ "renesas,i2c-r8a7796"
- reg: physical base address of the controller and length of memory mapped
region.
- interrupts: interrupt specifier.
diff --git a/Documentation/devicetree/bindings/i2c/nxp,pca9541.txt b/Documentation/devicetree/bindings/i2c/nxp,pca9541.txt
new file mode 100644
index 000000000000..0fbbc6970ec5
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/nxp,pca9541.txt
@@ -0,0 +1,29 @@
+* NXP PCA9541 I2C bus master selector
+
+Required Properties:
+
+ - compatible: Must be "nxp,pca9541"
+
+ - reg: The I2C address of the device.
+
+ The following required properties are defined externally:
+
+ - I2C arbitration bus node. See i2c-arb.txt in this directory.
+
+
+Example:
+
+ i2c-arbitrator@74 {
+ compatible = "nxp,pca9541";
+ reg = <0x74>;
+
+ i2c-arb {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ eeprom@54 {
+ compatible = "at,24c08";
+ reg = <0x54>;
+ };
+ };
+ };