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authorLinus Torvalds <torvalds@linux-foundation.org>2015-02-21 12:41:50 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-21 12:41:50 -0800
commit295324556c427d60b41668ab81a43f604533f456 (patch)
treea9a9acc5f790ba7093ee61a295bba7ac1f54a298 /Documentation
parent18a8d49973667aa016e68826eeb374788b7c63b0 (diff)
parent0d8fb59924cf20e7bef2c41f8d4e87127f573546 (diff)
Merge branch 'i2c/for-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: "Summary: - legacy PM code removed from the core, there were no users anymore (thanks to Lars-Peter Clausen) - new driver for Broadcom iProc - bigger driver updates for designware, rk3x, cadence, ocores - a bunch of smaller updates and bugfixes" * 'i2c/for-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (31 commits) i2c: ocores: rework clk code to handle NULL cookie i2c: designware-baytrail: another fixup for proper Kconfig dependencies i2c: fix reference to functionality constants definition i2c: iproc: Add Broadcom iProc I2C Driver i2c: designware-pci: update Intel copyright line i2c: ocores: add common clock support i2c: hix5hd2: add COMPILE_TEST i2c: clarify comments about the dev_released completion i2c: ocores: fix clock-frequency binding usage i2c: tegra: Maintain CPU endianness i2c: designware-baytrail: use proper Kconfig dependencies i2c: designware: Do not calculate SCL timing parameters needlessly i2c: do not try to load modules for of-registered devices i2c: designware: Add Intel Baytrail PMIC I2C bus support i2c: designware: Add i2c bus locking support of: i2c: Add i2c-mux-idle-disconnect DT property to PCA954x mux driver i2c: designware: use {readl|writel}_relaxed instead of readl/writel i2c: designware-pci: no need to provide clk_khz i2c: designware-pci: remove Moorestown support i2c: imx: whitespace and checkpatch cleanup ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/i2c/brcm,iproc-i2c.txt37
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt3
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-ocores.txt42
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-rk3x.txt14
-rw-r--r--Documentation/devicetree/bindings/i2c/trivial-devices.txt5
-rw-r--r--Documentation/i2c/functionality2
6 files changed, 96 insertions, 7 deletions
diff --git a/Documentation/devicetree/bindings/i2c/brcm,iproc-i2c.txt b/Documentation/devicetree/bindings/i2c/brcm,iproc-i2c.txt
new file mode 100644
index 000000000000..81f982ccca31
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/brcm,iproc-i2c.txt
@@ -0,0 +1,37 @@
+Broadcom iProc I2C controller
+
+Required properties:
+
+- compatible:
+ Must be "brcm,iproc-i2c"
+
+- reg:
+ Define the base and range of the I/O address space that contain the iProc
+ I2C controller registers
+
+- interrupts:
+ Should contain the I2C interrupt
+
+- clock-frequency:
+ This is the I2C bus clock. Need to be either 100000 or 400000
+
+- #address-cells:
+ Always 1 (for I2C addresses)
+
+- #size-cells:
+ Always 0
+
+Example:
+ i2c0: i2c@18008000 {
+ compatible = "brcm,iproc-i2c";
+ reg = <0x18008000 0x100>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ interrupts = <GIC_SPI 85 IRQ_TYPE_NONE>;
+ clock-frequency = <100000>;
+
+ codec: wm8750@1a {
+ compatible = "wlf,wm8750";
+ reg = <0x1a>;
+ };
+ };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt
index 34a3fb6f8488..cf53d5fba20a 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.txt
@@ -16,6 +16,9 @@ Required Properties:
Optional Properties:
- reset-gpios: Reference to the GPIO connected to the reset input.
+ - i2c-mux-idle-disconnect: Boolean; if defined, forces mux to disconnect all
+ children in idle state. This is necessary for example, if there are several
+ multiplexers on the bus and the devices behind them use same I2C addresses.
Example:
diff --git a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
index 1637c298a1b3..17bef9a34e50 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
@@ -4,24 +4,60 @@ Required properties:
- compatible : "opencores,i2c-ocores" or "aeroflexgaisler,i2cmst"
- reg : bus address start and address range size of device
- interrupts : interrupt number
-- clock-frequency : frequency of bus clock in Hz
+- clocks : handle to the controller clock; see the note below.
+ Mutually exclusive with opencores,ip-clock-frequency
+- opencores,ip-clock-frequency: frequency of the controller clock in Hz;
+ see the note below. Mutually exclusive with clocks
- #address-cells : should be <1>
- #size-cells : should be <0>
Optional properties:
+- clock-frequency : frequency of bus clock in Hz; see the note below.
+ Defaults to 100 KHz when the property is not specified
- reg-shift : device register offsets are shifted by this value
- reg-io-width : io register width in bytes (1, 2 or 4)
- regstep : deprecated, use reg-shift above
-Example:
+Note
+clock-frequency property is meant to control the bus frequency for i2c bus
+drivers, but it was incorrectly used to specify i2c controller input clock
+frequency. So the following rules are set to fix this situation:
+- if clock-frequency is present and neither opencores,ip-clock-frequency nor
+ clocks are, then clock-frequency specifies i2c controller clock frequency.
+ This is to keep backwards compatibility with setups using old DTB. i2c bus
+ frequency is fixed at 100 KHz.
+- if clocks is present it specifies i2c controller clock. clock-frequency
+ property specifies i2c bus frequency.
+- if opencores,ip-clock-frequency is present it specifies i2c controller
+ clock frequency. clock-frequency property specifies i2c bus frequency.
+Examples:
+
+ i2c0: ocores@a0000000 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "opencores,i2c-ocores";
+ reg = <0xa0000000 0x8>;
+ interrupts = <10>;
+ opencores,ip-clock-frequency = <20000000>;
+
+ reg-shift = <0>; /* 8 bit registers */
+ reg-io-width = <1>; /* 8 bit read/write */
+
+ dummy@60 {
+ compatible = "dummy";
+ reg = <0x60>;
+ };
+ };
+or
i2c0: ocores@a0000000 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "opencores,i2c-ocores";
reg = <0xa0000000 0x8>;
interrupts = <10>;
- clock-frequency = <20000000>;
+ clocks = <&osc>;
+ clock-frequency = <400000>; /* i2c bus frequency 400 KHz */
reg-shift = <0>; /* 8 bit registers */
reg-io-width = <1>; /* 8 bit read/write */
diff --git a/Documentation/devicetree/bindings/i2c/i2c-rk3x.txt b/Documentation/devicetree/bindings/i2c/i2c-rk3x.txt
index dde6c22ce91a..f0d71bc52e64 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-rk3x.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-rk3x.txt
@@ -21,6 +21,17 @@ Required on RK3066, RK3188 :
Optional properties :
- clock-frequency : SCL frequency to use (in Hz). If omitted, 100kHz is used.
+ - i2c-scl-rising-time-ns : Number of nanoseconds the SCL signal takes to rise
+ (t(r) in I2C specification). If not specified this is assumed to be
+ the maximum the specification allows(1000 ns for Standard-mode,
+ 300 ns for Fast-mode) which might cause slightly slower communication.
+ - i2c-scl-falling-time-ns : Number of nanoseconds the SCL signal takes to fall
+ (t(f) in the I2C specification). If not specified this is assumed to
+ be the maximum the specification allows (300 ns) which might cause
+ slightly slower communication.
+ - i2c-sda-falling-time-ns : Number of nanoseconds the SDA signal takes to fall
+ (t(f) in the I2C specification). If not specified we'll use the SCL
+ value since they are the same in nearly all cases.
Example:
@@ -39,4 +50,7 @@ i2c0: i2c@2002d000 {
clock-names = "i2c";
clocks = <&cru PCLK_I2C0>;
+
+ i2c-scl-rising-time-ns = <800>;
+ i2c-scl-falling-time-ns = <100>;
};
diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index 4dcd88d5f7ca..aaa8325004d2 100644
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -61,9 +61,8 @@ fsl,sgtl5000 SGTL5000: Ultra Low-Power Audio Codec
gmt,g751 G751: Digital Temperature Sensor and Thermal Watchdog with Two-Wire Interface
infineon,slb9635tt Infineon SLB9635 (Soft-) I2C TPM (old protocol, max 100khz)
infineon,slb9645tt Infineon SLB9645 I2C TPM (new protocol, max 400khz)
-isl,isl12057 Intersil ISL12057 I2C RTC Chip
-isil,isl29028 (deprecated, use isl)
-isl,isl29028 Intersil ISL29028 Ambient Light and Proximity Sensor
+isil,isl12057 Intersil ISL12057 I2C RTC Chip
+isil,isl29028 Intersil ISL29028 Ambient Light and Proximity Sensor
maxim,ds1050 5 Bit Programmable, Pulse-Width Modulator
maxim,max1237 Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
maxim,max6625 9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface
diff --git a/Documentation/i2c/functionality b/Documentation/i2c/functionality
index 4556a3eb87c4..4aae8ed15873 100644
--- a/Documentation/i2c/functionality
+++ b/Documentation/i2c/functionality
@@ -12,7 +12,7 @@ FUNCTIONALITY CONSTANTS
-----------------------
For the most up-to-date list of functionality constants, please check
-<linux/i2c.h>!
+<uapi/linux/i2c.h>!
I2C_FUNC_I2C Plain i2c-level commands (Pure SMBus
adapters typically can not do these)

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