summaryrefslogtreecommitdiff
path: root/Documentation
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-19 23:57:45 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-19 23:57:45 +0300
commit34b85e3574424beb30e4cd163e6da2e2282d2683 (patch)
tree8962201bcfb406db85796f2690f92bcc051373f4 /Documentation
parentd5e80b4b1857d5175bc6815aeefbb0e19b1a2c9b (diff)
parentd70a54e2d08510a99b1f10eceeae6f2f7086e226 (diff)
downloadlinux-34b85e3574424beb30e4cd163e6da2e2282d2683.tar.xz
Merge tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull second batch of powerpc updates from Michael Ellerman: "The highlight is the series that reworks the idle management on powernv, which allows us to use deeper idle states on those machines. There's the fix from Anton for the "BUG at kernel/smpboot.c:134!" problem. An i2c driver for powernv. This is acked by Wolfram Sang, and he asked that we take it through the powerpc tree. A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of the audit maintainers. A patch from Ben to export the symbol map of our OPAL firmware as a sysfs file, so that tools can use it. Also some CXL fixes, a couple of powerpc perf fixes, a fix for smt-enabled, and the patch to add __force to get_user() so we can use bitwise types" * tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/powernv: Ignore smt-enabled on Power8 and later powerpc/uaccess: Allow get_user() with bitwise types powerpc/powernv: Expose OPAL firmware symbol map powernv/powerpc: Add winkle support for offline cpus powernv/cpuidle: Redesign idle states management powerpc/powernv: Enable Offline CPUs to enter deep idle states powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode i2c: Driver to expose PowerNV platform i2c busses powerpc: add little endian flag to syscall_get_arch() power/perf/hv-24x7: Use kmem_cache_free() instead of kfree powerpc/perf/hv-24x7: Use per-cpu page buffer cxl: Unmap MMIO regions when detaching a context cxl: Add timeout to process element commands cxl: Change contexts_lock to a mutex to fix sleep while atomic bug powerpc: Secondary CPUs must set cpu_callin_map after setting active and online
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-opal.txt37
1 files changed, 37 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-opal.txt b/Documentation/devicetree/bindings/i2c/i2c-opal.txt
new file mode 100644
index 000000000000..12bc61465ee5
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-opal.txt
@@ -0,0 +1,37 @@
+Device-tree bindings for I2C OPAL driver
+----------------------------------------
+
+Most of the device node and properties layout is specific to the firmware and
+used by the firmware itself for configuring the port. From the linux
+perspective, the properties of use are "ibm,port-name" and "ibm,opal-id".
+
+Required properties:
+
+- reg: Port-id within a given master
+- compatible: must be "ibm,opal-i2c"
+- ibm,opal-id: Refers to a specific bus and used to identify it when calling
+ the relevant OPAL functions.
+- bus-frequency: Operating frequency of the i2c bus (in HZ). Informational for
+ linux, used by the FW though.
+
+Optional properties:
+- ibm,port-name: Firmware provides this name that uniquely identifies the i2c
+ port.
+
+The node contains a number of other properties that are used by the FW itself
+and depend on the specific hardware implementation. The example below depicts
+a P8 on-chip bus.
+
+Example:
+
+i2c-bus@0 {
+ reg = <0x0>;
+ bus-frequency = <0x61a80>;
+ compatible = "ibm,power8-i2c-port", "ibm,opal-i2c";
+ ibm,opal-id = <0x1>;
+ ibm,port-name = "p8_00000000_e1p0";
+ #address-cells = <0x1>;
+ phandle = <0x10000006>;
+ #size-cells = <0x0>;
+ linux,phandle = <0x10000006>;
+};