Merge tag 'v3.13-rc7' into x86/efi-kexec to resolve conflicts

Conflicts:
	arch/x86/platform/efi/efi.c
	drivers/firmware/efi/Kconfig

Signed-off-by: Ingo Molnar <mingo@kernel.org>

33 files changed, 1151 insertions, 68 deletions

diff --git a/Documentation/Changes b/Documentation/Changes
index b17580885273..07c75d18154e 100644
--- a/Documentation/Changes
+++ b/Documentation/Changes
@@ -196,13 +196,6 @@ chmod 0644 /dev/cpu/microcode
 as root before you can use this.  You'll probably also want to
 get the user-space microcode_ctl utility to use with this.
 
-Powertweak
-----------
-
-If you are running v0.1.17 or earlier, you should upgrade to
-version v0.99.0 or higher. Running old versions may cause problems
-with programs using shared memory.
-
 udev
 ----
 udev is a userspace application for populating /dev dynamically with
@@ -366,10 +359,6 @@ Intel P6 microcode
 ------------------
 o  <http://www.urbanmyth.org/microcode/>
 
-Powertweak
-----------
-o  <http://powertweak.sourceforge.net/>
-
 udev
 ----
 o <http://www.kernel.org/pub/linux/utils/kernel/hotplug/udev.html>
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index 6c9d9d37c83a..f5170082bdb3 100644
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -58,7 +58,7 @@
      </sect1>
      <sect1><title>Wait queues and Wake events</title>
 !Iinclude/linux/wait.h
-!Ekernel/wait.c
+!Ekernel/sched/wait.c
      </sect1>
      <sect1><title>High-resolution timers</title>
 !Iinclude/linux/ktime.h
diff --git a/Documentation/DocBook/media/v4l/vidioc-expbuf.xml b/Documentation/DocBook/media/v4l/vidioc-expbuf.xml
index e287c8fc803b..4165e7bfa4ff 100644
--- a/Documentation/DocBook/media/v4l/vidioc-expbuf.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-expbuf.xml
@@ -73,7 +73,8 @@ range from zero to the maximal number of valid planes for the currently active
 format. For the single-planar API, applications must set <structfield> plane
 </structfield> to zero.  Additional flags may be posted in the <structfield>
 flags </structfield> field.  Refer to a manual for open() for details.
-Currently only O_CLOEXEC is supported.  All other fields must be set to zero.
+Currently only O_CLOEXEC, O_RDONLY, O_WRONLY, and O_RDWR are supported.  All
+other fields must be set to zero.
 In the case of multi-planar API, every plane is exported separately using
 multiple <constant> VIDIOC_EXPBUF </constant> calls. </para>
 
@@ -170,8 +171,9 @@ multi-planar API. Otherwise this value must be set to zero. </entry>
 	    <entry>__u32</entry>
 	    <entry><structfield>flags</structfield></entry>
 	    <entry>Flags for the newly created file, currently only <constant>
-O_CLOEXEC </constant> is supported, refer to the manual of open() for more
-details.</entry>
+O_CLOEXEC </constant>, <constant>O_RDONLY</constant>, <constant>O_WRONLY
+</constant>, and <constant>O_RDWR</constant> are supported, refer to the manual
+of open() for more details.</entry>
 	  </row>
 	  <row>
 	    <entry>__s32</entry>
diff --git a/Documentation/assoc_array.txt b/Documentation/assoc_array.txt
index f4faec0f66e4..2f2c6cdd73c0 100644
--- a/Documentation/assoc_array.txt
+++ b/Documentation/assoc_array.txt
@@ -164,10 +164,10 @@ This points to a number of methods, all of which need to be provided:
 
  (4) Diff the index keys of two objects.
 
-	int (*diff_objects)(const void *a, const void *b);
+	int (*diff_objects)(const void *object, const void *index_key);
 
-     Return the bit position at which the index keys of two objects differ or
-     -1 if they are the same.
+     Return the bit position at which the index key of the specified object
+     differs from the given index key or -1 if they are the same.
 
 
  (5) Free an object.
diff --git a/Documentation/block/null_blk.txt b/Documentation/block/null_blk.txt
new file mode 100644
index 000000000000..b2830b435895
--- /dev/null
+++ b/Documentation/block/null_blk.txt
@@ -0,0 +1,72 @@
+Null block device driver
+================================================================================
+
+I. Overview
+
+The null block device (/dev/nullb*) is used for benchmarking the various
+block-layer implementations. It emulates a block device of X gigabytes in size.
+The following instances are possible:
+
+  Single-queue block-layer
+    - Request-based.
+    - Single submission queue per device.
+    - Implements IO scheduling algorithms (CFQ, Deadline, noop).
+  Multi-queue block-layer
+    - Request-based.
+    - Configurable submission queues per device.
+  No block-layer (Known as bio-based)
+    - Bio-based. IO requests are submitted directly to the device driver.
+    - Directly accepts bio data structure and returns them.
+
+All of them have a completion queue for each core in the system.
+
+II. Module parameters applicable for all instances:
+
+queue_mode=[0-2]: Default: 2-Multi-queue
+  Selects which block-layer the module should instantiate with.
+
+  0: Bio-based.
+  1: Single-queue.
+  2: Multi-queue.
+
+home_node=[0--nr_nodes]: Default: NUMA_NO_NODE
+  Selects what CPU node the data structures are allocated from.
+
+gb=[Size in GB]: Default: 250GB
+  The size of the device reported to the system.
+
+bs=[Block size (in bytes)]: Default: 512 bytes
+  The block size reported to the system.
+
+nr_devices=[Number of devices]: Default: 2
+  Number of block devices instantiated. They are instantiated as /dev/nullb0,
+  etc.
+
+irq_mode=[0-2]: Default: 1-Soft-irq
+  The completion mode used for completing IOs to the block-layer.
+
+  0: None.
+  1: Soft-irq. Uses IPI to complete IOs across CPU nodes. Simulates the overhead
+     when IOs are issued from another CPU node than the home the device is
+     connected to.
+  2: Timer: Waits a specific period (completion_nsec) for each IO before
+     completion.
+
+completion_nsec=[ns]: Default: 10.000ns
+  Combined with irq_mode=2 (timer). The time each completion event must wait.
+
+submit_queues=[0..nr_cpus]:
+  The number of submission queues attached to the device driver. If unset, it
+  defaults to 1 on single-queue and bio-based instances. For multi-queue,
+  it is ignored when use_per_node_hctx module parameter is 1.
+
+hw_queue_depth=[0..qdepth]: Default: 64
+  The hardware queue depth of the device.
+
+III: Multi-queue specific parameters
+
+use_per_node_hctx=[0/1]: Default: 0
+  0: The number of submit queues are set to the value of the submit_queues
+     parameter.
+  1: The multi-queue block layer is instantiated with a hardware dispatch
+     queue for each CPU node in the system.
diff --git a/Documentation/device-mapper/cache.txt b/Documentation/device-mapper/cache.txt
index 274752f8bdf9..719320b5ed3f 100644
--- a/Documentation/device-mapper/cache.txt
+++ b/Documentation/device-mapper/cache.txt
@@ -266,10 +266,12 @@ E.g.
 Invalidation is removing an entry from the cache without writing it
 back.  Cache blocks can be invalidated via the invalidate_cblocks
 message, which takes an arbitrary number of cblock ranges.  Each cblock
-must be expressed as a decimal value, in the future a variant message
-that takes cblock ranges expressed in hexidecimal may be needed to
-better support efficient invalidation of larger caches.  The cache must
-be in passthrough mode when invalidate_cblocks is used.
+range's end value is "one past the end", meaning 5-10 expresses a range
+of values from 5 to 9.  Each cblock must be expressed as a decimal
+value, in the future a variant message that takes cblock ranges
+expressed in hexidecimal may be needed to better support efficient
+invalidation of larger caches.  The cache must be in passthrough mode
+when invalidate_cblocks is used.
 
    invalidate_cblocks [<cblock>|<cblock begin>-<cblock end>]*
 
diff --git a/Documentation/devicetree/bindings/arm/omap/mpu.txt b/Documentation/devicetree/bindings/arm/omap/mpu.txt
index 1a5a42ce21bb..83f405bde138 100644
--- a/Documentation/devicetree/bindings/arm/omap/mpu.txt
+++ b/Documentation/devicetree/bindings/arm/omap/mpu.txt
@@ -7,10 +7,18 @@ The MPU contain CPUs, GIC, L2 cache and a local PRCM.
 Required properties:
 - compatible : Should be "ti,omap3-mpu" for OMAP3
                Should be "ti,omap4-mpu" for OMAP4
+	       Should be "ti,omap5-mpu" for OMAP5
 - ti,hwmods: "mpu"
 
 Examples:
 
+- For an OMAP5 SMP system:
+
+mpu {
+    compatible = "ti,omap5-mpu";
+    ti,hwmods = "mpu"
+};
+
 - For an OMAP4 SMP system:
 
 mpu {
diff --git a/Documentation/devicetree/bindings/arm/pmu.txt b/Documentation/devicetree/bindings/arm/pmu.txt
index 343781b9f246..3e1e498fea96 100644
--- a/Documentation/devicetree/bindings/arm/pmu.txt
+++ b/Documentation/devicetree/bindings/arm/pmu.txt
@@ -7,6 +7,7 @@ representation in the device tree should be done as under:-
 Required properties:
 
 - compatible : should be one of
+	"arm,armv8-pmuv3"
 	"arm,cortex-a15-pmu"
 	"arm,cortex-a9-pmu"
 	"arm,cortex-a8-pmu"
diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
index 47ada1dff216..5d49f2b37f68 100644
--- a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
+++ b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
@@ -49,7 +49,7 @@ adc@12D10000 {
 	/* NTC thermistor is a hwmon device */
 	ncp15wb473@0 {
 		compatible = "ntc,ncp15wb473";
-		pullup-uV = <1800000>;
+		pullup-uv = <1800000>;
 		pullup-ohm = <47000>;
 		pulldown-ohm = <0>;
 		io-channels = <&adc 4>;
diff --git a/Documentation/devicetree/bindings/clock/exynos4-clock.txt b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
index c6bf8a6c8f52..a2ac2d9ac71a 100644
--- a/Documentation/devicetree/bindings/clock/exynos4-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
@@ -6,7 +6,7 @@ SoC's in the Exynos4 family.
 
 Required Properties:
 
-- comptible: should be one of the following.
+- compatible: should be one of the following.
   - "samsung,exynos4210-clock" - controller compatible with Exynos4210 SoC.
   - "samsung,exynos4412-clock" - controller compatible with Exynos4412 SoC.
 
diff --git a/Documentation/devicetree/bindings/clock/exynos5250-clock.txt b/Documentation/devicetree/bindings/clock/exynos5250-clock.txt
index 24765c146e31..46f5c791ea0d 100644
--- a/Documentation/devicetree/bindings/clock/exynos5250-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos5250-clock.txt
@@ -5,7 +5,7 @@ controllers within the Exynos5250 SoC.
 
 Required Properties:
 
-- comptible: should be one of the following.
+- compatible: should be one of the following.
   - "samsung,exynos5250-clock" - controller compatible with Exynos5250 SoC.
 
 - reg: physical base address of the controller and length of memory mapped
diff --git a/Documentation/devicetree/bindings/clock/exynos5420-clock.txt b/Documentation/devicetree/bindings/clock/exynos5420-clock.txt
index 32aa34ecad36..458f34789e5d 100644
--- a/Documentation/devicetree/bindings/clock/exynos5420-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos5420-clock.txt
@@ -5,7 +5,7 @@ controllers within the Exynos5420 SoC.
 
 Required Properties:
 
-- comptible: should be one of the following.
+- compatible: should be one of the following.
   - "samsung,exynos5420-clock" - controller compatible with Exynos5420 SoC.
 
 - reg: physical base address of the controller and length of memory mapped
diff --git a/Documentation/devicetree/bindings/clock/exynos5440-clock.txt b/Documentation/devicetree/bindings/clock/exynos5440-clock.txt
index 4499e9966bc9..9955dc9c7d96 100644
--- a/Documentation/devicetree/bindings/clock/exynos5440-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos5440-clock.txt
@@ -5,7 +5,7 @@ controllers within the Exynos5440 SoC.
 
 Required Properties:
 
-- comptible: should be "samsung,exynos5440-clock".
+- compatible: should be "samsung,exynos5440-clock".
 
 - reg: physical base address of the controller and length of memory mapped
   region.
diff --git a/Documentation/devicetree/bindings/gpio/8xxx_gpio.txt b/Documentation/devicetree/bindings/gpio/8xxx_gpio.txt
index b0019eb5330e..798cfc9d3839 100644
--- a/Documentation/devicetree/bindings/gpio/8xxx_gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/8xxx_gpio.txt
@@ -5,16 +5,42 @@ This is for the non-QE/CPM/GUTs GPIO controllers as found on
 
 Every GPIO controller node must have #gpio-cells property defined,
 this information will be used to translate gpio-specifiers.
+See bindings/gpio/gpio.txt for details of how to specify GPIO
+information for devices.
+
+The GPIO module usually is connected to the SoC's internal interrupt
+controller, see bindings/interrupt-controller/interrupts.txt (the
+interrupt client nodes section) for details how to specify this GPIO
+module's interrupt.
+
+The GPIO module may serve as another interrupt controller (cascaded to
+the SoC's internal interrupt controller).  See the interrupt controller
+nodes section in bindings/interrupt-controller/interrupts.txt for
+details.
 
 Required properties:
-- compatible : "fsl,<CHIP>-gpio" followed by "fsl,mpc8349-gpio" for
-  83xx, "fsl,mpc8572-gpio" for 85xx and "fsl,mpc8610-gpio" for 86xx.
-- #gpio-cells : Should be two. The first cell is the pin number and the
-  second cell is used to specify optional parameters (currently unused).
- - interrupts : Interrupt mapping for GPIO IRQ.
- - interrupt-parent : Phandle for the interrupt controller that
-   services interrupts for this device.
-- gpio-controller : Marks the port as GPIO controller.
+- compatible:		"fsl,<chip>-gpio" followed by "fsl,mpc8349-gpio"
+			for 83xx, "fsl,mpc8572-gpio" for 85xx, or
+			"fsl,mpc8610-gpio" for 86xx.
+- #gpio-cells:		Should be two. The first cell is the pin number
+			and the second cell is used to specify optional
+			parameters (currently unused).
+- interrupt-parent:	Phandle for the interrupt controller that
+			services interrupts for this device.
+- interrupts:		Interrupt mapping for GPIO IRQ.
+- gpio-controller:	Marks the port as GPIO controller.
+
+Optional properties:
+- interrupt-controller:	Empty boolean property which marks the GPIO
+			module as an IRQ controller.
+- #interrupt-cells:	Should be two.  Defines the number of integer
+			cells required to specify an interrupt within
+			this interrupt controller.  The first cell
+			defines the pin number, the second cell
+			defines additional flags (trigger type,
+			trigger polarity).  Note that the available
+			set of trigger conditions supported by the
+			GPIO module depends on the actual SoC.
 
 Example of gpio-controller nodes for a MPC8347 SoC:
 
@@ -22,39 +48,27 @@ Example of gpio-controller nodes for a MPC8347 SoC:
 		#gpio-cells = <2>;
 		compatible = "fsl,mpc8347-gpio", "fsl,mpc8349-gpio";
 		reg = <0xc00 0x100>;
-		interrupts = <74 0x8>;
 		interrupt-parent = <&ipic>;
+		interrupts = <74 0x8>;
 		gpio-controller;
+		interrupt-controller;
+		#interrupt-cells = <2>;
 	};
 
 	gpio2: gpio-controller@d00 {
 		#gpio-cells = <2>;
 		compatible = "fsl,mpc8347-gpio", "fsl,mpc8349-gpio";
 		reg = <0xd00 0x100>;
-		interrupts = <75 0x8>;
 		interrupt-parent = <&ipic>;
+		interrupts = <75 0x8>;
 		gpio-controller;
 	};
 
-See booting-without-of.txt for details of how to specify GPIO
-information for devices.
-
-To use GPIO pins as interrupt sources for peripherals, specify the
-GPIO controller as the interrupt parent and define GPIO number +
-trigger mode using the interrupts property, which is defined like
-this:
-
-interrupts = <number trigger>, where:
- - number: GPIO pin (0..31)
- - trigger: trigger mode:
-	2 = trigger on falling edge
-	3 = trigger on both edges
-
-Example of device using this is:
+Example of a peripheral using the GPIO module as an IRQ controller:
 
 	funkyfpga@0 {
 		compatible = "funky-fpga";
 		...
-		interrupts = <4 3>;
 		interrupt-parent = <&gpio1>;
+		interrupts = <4 3>;
 	};
diff --git a/Documentation/devicetree/bindings/i2c/i2c-omap.txt b/Documentation/devicetree/bindings/i2c/i2c-omap.txt
index 56564aa4b444..7e49839d4124 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-omap.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-omap.txt
@@ -1,7 +1,8 @@
 I2C for OMAP platforms
 
 Required properties :
-- compatible : Must be "ti,omap3-i2c" or "ti,omap4-i2c"
+- compatible : Must be "ti,omap2420-i2c", "ti,omap2430-i2c", "ti,omap3-i2c"
+  or "ti,omap4-i2c"
 - ti,hwmods : Must be "i2c<n>", n being the instance number (1-based)
 - #address-cells = <1>;
 - #size-cells = <0>;
diff --git a/Documentation/devicetree/bindings/mmc/ti-omap.txt b/Documentation/devicetree/bindings/mmc/ti-omap.txt
new file mode 100644
index 000000000000..8de579969763
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/ti-omap.txt
@@ -0,0 +1,54 @@
+* TI MMC host controller for OMAP1 and 2420
+
+The MMC Host Controller on TI OMAP1 and 2420 family provides
+an interface for MMC, SD, and SDIO types of memory cards.
+
+This file documents differences between the core properties described
+by mmc.txt and the properties used by the omap mmc driver.
+
+Note that this driver will not work with omap2430 or later omaps,
+please see the omap hsmmc driver for the current omaps.
+
+Required properties:
+- compatible: Must be "ti,omap2420-mmc", for OMAP2420 controllers
+- ti,hwmods: For 2420, must be "msdi<n>", where n is controller
+  instance starting 1
+
+Examples:
+
+	msdi1: mmc@4809c000 {
+		compatible = "ti,omap2420-mmc";
+		ti,hwmods = "msdi1";
+		reg = <0x4809c000 0x80>;
+		interrupts = <83>;
+		dmas = <&sdma 61 &sdma 62>;
+		dma-names = "tx", "rx";
+	};
+
+* TI MMC host controller for OMAP1 and 2420
+
+The MMC Host Controller on TI OMAP1 and 2420 family provides
+an interface for MMC, SD, and SDIO types of memory cards.
+
+This file documents differences between the core properties described
+by mmc.txt and the properties used by the omap mmc driver.
+
+Note that this driver will not work with omap2430 or later omaps,
+please see the omap hsmmc driver for the current omaps.
+
+Required properties:
+- compatible: Must be "ti,omap2420-mmc", for OMAP2420 controllers
+- ti,hwmods: For 2420, must be "msdi<n>", where n is controller
+  instance starting 1
+
+Examples:
+
+	msdi1: mmc@4809c000 {
+		compatible = "ti,omap2420-mmc";
+		ti,hwmods = "msdi1";
+		reg = <0x4809c000 0x80>;
+		interrupts = <83>;
+		dmas = <&sdma 61 &sdma 62>;
+		dma-names = "tx", "rx";
+	};
+
diff --git a/Documentation/devicetree/bindings/net/davinci_emac.txt b/Documentation/devicetree/bindings/net/davinci_emac.txt
index 48b259e29e87..bad381faf036 100644
--- a/Documentation/devicetree/bindings/net/davinci_emac.txt
+++ b/Documentation/devicetree/bindings/net/davinci_emac.txt
@@ -4,7 +4,7 @@ This file provides information, what the device node
 for the davinci_emac interface contains.
 
 Required properties:
-- compatible: "ti,davinci-dm6467-emac";
+- compatible: "ti,davinci-dm6467-emac" or "ti,am3517-emac"
 - reg: Offset and length of the register set for the device
 - ti,davinci-ctrl-reg-offset: offset to control register
 - ti,davinci-ctrl-mod-reg-offset: offset to control module register
diff --git a/Documentation/devicetree/bindings/net/fsl-fec.txt b/Documentation/devicetree/bindings/net/fsl-fec.txt
index d53639221403..845ff848d895 100644
--- a/Documentation/devicetree/bindings/net/fsl-fec.txt
+++ b/Documentation/devicetree/bindings/net/fsl-fec.txt
@@ -15,6 +15,7 @@ Optional properties:
   only if property "phy-reset-gpios" is available.  Missing the property
   will have the duration be 1 millisecond.  Numbers greater than 1000 are
   invalid and 1 millisecond will be used instead.
+- phy-supply: regulator that powers the Ethernet PHY.
 
 Example:
 
@@ -25,4 +26,5 @@ ethernet@83fec000 {
 	phy-mode = "mii";
 	phy-reset-gpios = <&gpio2 14 0>; /* GPIO2_14 */
 	local-mac-address = [00 04 9F 01 1B B9];
+	phy-supply = <&reg_fec_supply>;
 };
diff --git a/Documentation/devicetree/bindings/net/smsc-lan91c111.txt b/Documentation/devicetree/bindings/net/smsc-lan91c111.txt
index 953049b4248a..5a41a8658daa 100644
--- a/Documentation/devicetree/bindings/net/smsc-lan91c111.txt
+++ b/Documentation/devicetree/bindings/net/smsc-lan91c111.txt
@@ -8,3 +8,7 @@ Required properties:
 Optional properties:
 - phy-device : phandle to Ethernet phy
 - local-mac-address : Ethernet mac address to use
+- reg-io-width : Mask of sizes (in bytes) of the IO accesses that
+  are supported on the device.  Valid value for SMSC LAN91c111 are
+  1, 2 or 4.  If it's omitted or invalid, the size would be 2 meaning
+  16-bit access only.
diff --git a/Documentation/devicetree/bindings/spi/nvidia,tegra20-spi.txt b/Documentation/devicetree/bindings/spi/nvidia,tegra20-spi.txt
deleted file mode 100644
index 6b9e51896693..000000000000
--- a/Documentation/devicetree/bindings/spi/nvidia,tegra20-spi.txt
+++ /dev/null
@@ -1,5 +0,0 @@
-NVIDIA Tegra 2 SPI device
-
-Required properties:
-- compatible : should be "nvidia,tegra20-spi".
-- gpios : should specify GPIOs used for chipselect.
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index ce95ed1c6d3e..edbb8d88c85e 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -32,12 +32,14 @@ est	ESTeem Wireless Modems
 fsl	Freescale Semiconductor
 GEFanuc	GE Fanuc Intelligent Platforms Embedded Systems, Inc.
 gef	GE Fanuc Intelligent Platforms Embedded Systems, Inc.
+gmt	Global Mixed-mode Technology, Inc.
 hisilicon	Hisilicon Limited.
 hp	Hewlett Packard
 ibm	International Business Machines (IBM)
 idt	Integrated Device Technologies, Inc.
 img	Imagination Technologies Ltd.
 intercontrol	Inter Control Group
+lg	LG Corporation
 linux	Linux-specific binding
 lsi	LSI Corp. (LSI Logic)
 marvell	Marvell Technology Group Ltd.
diff --git a/Documentation/gpio/00-INDEX b/Documentation/gpio/00-INDEX
new file mode 100644
index 000000000000..1de43ae46ae6
--- /dev/null
+++ b/Documentation/gpio/00-INDEX
@@ -0,0 +1,14 @@
+00-INDEX
+	- This file
+gpio.txt
+	- Introduction to GPIOs and their kernel interfaces
+consumer.txt
+	- How to obtain and use GPIOs in a driver
+driver.txt
+	- How to write a GPIO driver
+board.txt
+	- How to assign GPIOs to a consumer device and a function
+sysfs.txt
+	- Information about the GPIO sysfs interface
+gpio-legacy.txt
+	- Historical documentation of the deprecated GPIO integer interface
diff --git a/Documentation/gpio/board.txt b/Documentation/gpio/board.txt
new file mode 100644
index 000000000000..0d03506f2cc5
--- /dev/null
+++ b/Documentation/gpio/board.txt
@@ -0,0 +1,115 @@
+GPIO Mappings
+=============
+
+This document explains how GPIOs can be assigned to given devices and functions.
+Note that it only applies to the new descriptor-based interface. For a
+description of the deprecated integer-based GPIO interface please refer to
+gpio-legacy.txt (actually, there is no real mapping possible with the old
+interface; you just fetch an integer from somewhere and request the
+corresponding GPIO.
+
+Platforms that make use of GPIOs must select ARCH_REQUIRE_GPIOLIB (if GPIO usage
+is mandatory) or ARCH_WANT_OPTIONAL_GPIOLIB (if GPIO support can be omitted) in
+their Kconfig. Then, how GPIOs are mapped depends on what the platform uses to
+describe its hardware layout. Currently, mappings can be defined through device
+tree, ACPI, and platform data.
+
+Device Tree
+-----------
+GPIOs can easily be mapped to devices and functions in the device tree. The
+exact way to do it depends on the GPIO controller providing the GPIOs, see the
+device tree bindings for your controller.
+
+GPIOs mappings are defined in the consumer device's node, in a property named
+<function>-gpios, where <function> is the function the driver will request
+through gpiod_get(). For example:
+
+	foo_device {
+		compatible = "acme,foo";
+		...
+		led-gpios = <&gpio 15 GPIO_ACTIVE_HIGH>, /* red */
+			    <&gpio 16 GPIO_ACTIVE_HIGH>, /* green */
+			    <&gpio 17 GPIO_ACTIVE_HIGH>; /* blue */
+
+		power-gpio = <&gpio 1 GPIO_ACTIVE_LOW>;
+	};
+
+This property will make GPIOs 15, 16 and 17 available to the driver under the
+"led" function, and GPIO 1 as the "power" GPIO:
+
+	struct gpio_desc *red, *green, *blue, *power;
+
+	red = gpiod_get_index(dev, "led", 0);
+	green = gpiod_get_index(dev, "led", 1);
+	blue = gpiod_get_index(dev, "led", 2);
+
+	power = gpiod_get(dev, "power");
+
+The led GPIOs will be active-high, while the power GPIO will be active-low (i.e.
+gpiod_is_active_low(power) will be true).
+
+ACPI
+----
+ACPI does not support function names for GPIOs. Therefore, only the "idx"
+argument of gpiod_get_index() is useful to discriminate between GPIOs assigned
+to a device. The "con_id" argument can still be set for debugging purposes (it
+will appear under error messages as well as debug and sysfs nodes).
+
+Platform Data
+-------------
+Finally, GPIOs can be bound to devices and functions using platform data. Board
+files that desire to do so need to include the following header:
+
+	#include <linux/gpio/driver.h>
+
+GPIOs are mapped by the means of tables of lookups, containing instances of the
+gpiod_lookup structure. Two macros are defined to help declaring such mappings:
+
+	GPIO_LOOKUP(chip_label, chip_hwnum, dev_id, con_id, flags)
+	GPIO_LOOKUP_IDX(chip_label, chip_hwnum, dev_id, con_id, idx, flags)
+
+where
+
+  - chip_label is the label of the gpiod_chip instance providing the GPIO
+  - chip_hwnum is the hardware number of the GPIO within the chip
+  - dev_id is the identifier of the device that will make use of this GPIO. If
+	NULL, the GPIO will be available to all devices.
+  - con_id is the name of the GPIO function from the device point of view. It
+	can be NULL.
+  - idx is the index of the GPIO within the function.
+  - flags is defined to specify the following properties:
+	* GPIOF_ACTIVE_LOW	- to configure the GPIO as active-low
+	* GPIOF_OPEN_DRAIN	- GPIO pin is open drain type.
+	* GPIOF_OPEN_SOURCE	- GPIO pin is open source type.
+
+In the future, these flags might be extended to support more properties.
+
+Note that GPIO_LOOKUP() is just a shortcut to GPIO_LOOKUP_IDX() where idx = 0.
+
+A lookup table can then be defined as follows:
+
+	struct gpiod_lookup gpios_table[] = {
+	GPIO_LOOKUP_IDX("gpio.0", 15, "foo.0", "led", 0, GPIO_ACTIVE_HIGH),
+	GPIO_LOOKUP_IDX("gpio.0", 16, "foo.0", "led", 1, GPIO_ACTIVE_HIGH),
+	GPIO_LOOKUP_IDX("gpio.0", 17, "foo.0", "led", 2, GPIO_ACTIVE_HIGH),
+	GPIO_LOOKUP("gpio.0", 1, "foo.0", "power", GPIO_ACTIVE_LOW),
+	};
+
+And the table can be added by the board code as follows:
+
+	gpiod_add_table(gpios_table, ARRAY_SIZE(gpios_table));
+
+The driver controlling "foo.0" will then be able to obtain its GPIOs as follows:
+
+	struct gpio_desc *red, *green, *blue, *power;
+
+	red = gpiod_get_index(dev, "led", 0);
+	green = gpiod_get_index(dev, "led", 1);
+	blue = gpiod_get_index(dev, "led", 2);
+
+	power = gpiod_get(dev, "power");
+	gpiod_direction_output(power, 1);
+
+Since the "power" GPIO is mapped as active-low, its actual signal will be 0
+after this code. Contrary to the legacy integer GPIO interface, the active-low
+property is handled during mapping and is thus transparent to GPIO consumers.
diff --git a/Documentation/gpio/consumer.txt b/Documentation/gpio/consumer.txt
new file mode 100644
index 000000000000..07c74a3765a0
--- /dev/null
+++ b/Documentation/gpio/consumer.txt
@@ -0,0 +1,197 @@
+GPIO Descriptor Consumer Interface
+==================================
+
+This document describes the consumer interface of the GPIO framework. Note that
+it describes the new descriptor-based interface. For a description of the
+deprecated integer-based GPIO interface please refer to gpio-legacy.txt.
+
+
+Guidelines for GPIOs consumers
+==============================
+
+Drivers that can't work without standard GPIO calls should have Kconfig entries
+that depend on GPIOLIB. The functions that allow a driver to obtain and use
+GPIOs are available by including the following file:
+
+	#include <linux/gpio/consumer.h>
+
+All the functions that work with the descriptor-based GPIO interface are
+prefixed with gpiod_. The gpio_ prefix is used for the legacy interface. No
+other function in the kernel should use these prefixes.
+
+
+Obtaining and Disposing GPIOs
+=============================
+
+With the descriptor-based interface, GPIOs are identified with an opaque,
+non-forgeable handler that must be obtained through a call to one of the
+gpiod_get() functions. Like many other kernel subsystems, gpiod_get() takes the
+device that will use the GPIO and the function the requested GPIO is supposed to
+fulfill:
+
+	struct gpio_desc *gpiod_get(struct device *dev, const char *con_id)
+
+If a function is implemented by using several GPIOs together (e.g. a simple LED
+device that displays digits), an additional index argument can be specified:
+
+	struct gpio_desc *gpiod_get_index(struct device *dev,
+					  const char *con_id, unsigned int idx)
+
+Both functions return either a valid GPIO descriptor, or an error code checkable
+with IS_ERR(). They will never return a NULL pointer.
+
+Device-managed variants of these functions are also defined:
+
+	struct gpio_desc *devm_gpiod_get(struct device *dev, const char *con_id)
+
+	struct gpio_desc *devm_gpiod_get_index(struct device *dev,
+					       const char *con_id,
+					       unsigned int idx)
+
+A GPIO descriptor can be disposed of using the gpiod_put() function:
+
+	void gpiod_put(struct gpio_desc *desc)
+
+It is strictly forbidden to use a descriptor after calling this function. The
+device-managed variant is, unsurprisingly:
+
+	void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
+
+
+Using GPIOs
+===========
+
+Setting Direction
+-----------------
+The first thing a driver must do with a GPIO is setting its direction. This is
+done by invoking one of the gpiod_direction_*() functions:
+
+	int gpiod_direction_input(struct gpio_desc *desc)
+	int gpiod_direction_output(struct gpio_desc *desc, int value)
+
+The return value is zero for success, else a negative errno. It should be
+checked, since the get/set calls don't return errors and since misconfiguration
+is possible. You should normally issue these calls from a task context. However,
+for spinlock-safe GPIOs it is OK to use them before tasking is enabled, as part
+of early board setup.
+
+For output GPIOs, the value provided becomes the initial output value. This
+helps avoid signal glitching during system startup.
+
+A driver can also query the current direction of a GPIO:
+
+	int gpiod_get_direction(const struct gpio_desc *desc)
+
+This function will return either GPIOF_DIR_IN or GPIOF_DIR_OUT.
+
+Be aware that there is no default direction for GPIOs. Therefore, **using a GPIO
+without setting its direction first is illegal and will result in undefined
+behavior!**
+
+
+Spinlock-Safe GPIO Access
+-------------------------
+Most GPIO controllers can be accessed with memory read/write instructions. Those
+don't need to sleep, and can safely be done from inside hard (non-threaded) IRQ
+handlers and similar contexts.
+
+Use the following calls to access GPIOs from an atomic context:
+
+	int gpiod_get_value(const struct gpio_desc *desc);
+	void gpiod_set_value(struct gpio_desc *desc, int value);
+
+The values are boolean, zero for low, nonzero for high. When reading the value
+of an output pin, the value returned should be what's seen on the pin. That
+won't always match the specified output value, because of issues including
+open-drain signaling and output latencies.
+
+The get/set calls do not return errors because "invalid GPIO" should have been
+reported earlier from gpiod_direction_*(). However, note that not all platforms
+can read the value of output pins; those that can't should always return zero.
+Also, using these calls for GPIOs that can't safely be accessed without sleeping
+(see below) is an error.
+
+
+GPIO Access That May Sleep
+--------------------------
+Some GPIO controllers must be accessed using message based buses like I2C or
+SPI. Commands to read or write those GPIO values require waiting to get to the
+head of a queue to transmit a command and get its response. This requires
+sleeping, which can't be done from inside IRQ handlers.
+
+Platforms that support this type of GPIO distinguish them from other GPIOs by
+returning nonzero from this call:
+
+	int gpiod_cansleep(const struct gpio_desc *desc)
+
+To access such GPIOs, a different set of accessors is defined:
+
+	int gpiod_get_value_cansleep(const struct gpio_desc *desc)
+	void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
+
+Accessing such GPIOs requires a context which may sleep, for example a threaded
+IRQ handler, and those accessors must be used instead of spinlock-safe
+accessors without the cansleep() name suffix.
+
+Other than the fact that these accessors might sleep, and will work on GPIOs
+that can't be accessed from hardIRQ handlers, these calls act the same as the
+spinlock-safe calls.
+
+
+Active-low State and Raw GPIO Values
+------------------------------------
+Device drivers like to manage the logical state of a GPIO, i.e. the value their
+device will actually receive, no matter what lies between it and the GPIO line.
+In some cases, it might make sense to control the actual GPIO line value. The
+following set of calls ignore the active-low property of a GPIO and work on the
+raw line value:
+
+	int gpiod_get_raw_value(const struct gpio_desc *desc)
+	void gpiod_set_raw_value(struct gpio_desc *desc, int value)
+	int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
+	void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
+
+The active-low state of a GPIO can also be queried using the following call:
+
+	int gpiod_is_active_low(const struct gpio_desc *desc)
+
+Note that these functions should only be used with great moderation ; a driver
+should not have to care about the physical line level.
+
+GPIOs mapped to IRQs
+--------------------
+GPIO lines can quite often be used as IRQs. You can get the IRQ number
+corresponding to a given GPIO using the following call:
+
+	int gpiod_to_irq(const struct gpio_desc *desc)
+
+It will return an IRQ number, or an negative errno code if the mapping can't be
+done (most likely because that particular GPIO cannot be used as IRQ). It is an
+unchecked error to use a GPIO that wasn't set up as an input using
+gpiod_direction_input(), or to use an IRQ number that didn't originally come
+from gpiod_to_irq(). gpiod_to_irq() is not allowed to sleep.
+
+Non-error values returned from gpiod_to_irq() can be passed to request_irq() or
+free_irq(). They will often be stored into IRQ resources for platform devices,
+by the board-specific initialization code. Note that IRQ trigger options are
+part of the IRQ interface, e.g. IRQF_TRIGGER_FALLING, as are system wakeup
+capabilities.
+
+
+Interacting With the Legacy GPIO Subsystem
+==========================================
+Many kernel subsystems still handle GPIOs using the legacy integer-based
+interface. Although it is strongly encouraged to upgrade them to the safer
+descriptor-based API, the following two functions allow you to convert a GPIO
+descriptor into the GPIO integer namespace and vice-versa:
+
+	int desc_to_gpio(const struct gpio_desc *desc)
+	struct gpio_desc *gpio_to_desc(unsigned gpio)
+
+The GPIO number returned by desc_to_gpio() can be safely used as long as the
+GPIO descriptor has not been freed. All the same, a GPIO number passed to
+gpio_to_desc() must have been properly acquired, and usage of the returned GPIO
+descriptor is only possible after the GPIO number has been released.
+
+Freeing a GPIO obtained by one API with the other API is forbidden and an
+unchecked error.
diff --git a/Documentation/gpio/driver.txt b/Documentation/gpio/driver.txt
new file mode 100644
index 000000000000..9da0bfa74781
--- /dev/null
+++ b/Documentation/gpio/driver.txt
@@ -0,0 +1,75 @@
+GPIO Descriptor Driver Interface
+================================
+
+This document serves as a guide for GPIO chip drivers writers. Note that it
+describes the new descriptor-based interface. For a description of the
+deprecated integer-based GPIO interface please refer to gpio-legacy.txt.
+
+Each GPIO controller driver needs to include the following header, which defines
+the structures used to define a GPIO driver:
+
+	#include <linux/gpio/driver.h>
+
+
+Internal Representation of GPIOs
+================================
+
+Inside a GPIO driver, individual GPIOs are identified by their hardware number,
+which is a unique number between 0 and n, n being the number of GPIOs managed by
+the chip. This number is purely internal: the hardware number of a particular
+GPIO descriptor is never made visible outside of the driver.
+
+On top of this internal number, each GPIO also need to have a global number in
+the integer GPIO namespace so that it can be used with the legacy GPIO
+interface. Each chip must thus have a "base" number (which can be automatically
+assigned), and for each GPIO the global number will be (base + hardware number).
+Although the integer representation is considered deprecated, it still has many
+users and thus needs to be maintained.
+
+So for example one platform could use numbers 32-159 for GPIOs, with a
+controller defining 128 GPIOs at a "base" of 32 ; while another platform uses
+numbers 0..63 with one set of GPIO controllers, 64-79 with another type of GPIO
+controller, and on one particular board 80-95 with an FPGA. The numbers need not
+be contiguous; either of those platforms could also use numbers 2000-2063 to
+identify GPIOs in a bank of I2C GPIO expanders.
+
+
+Controller Drivers: gpio_chip
+=============================
+
+In the gpiolib framework each GPIO controller is packaged as a "struct
+gpio_chip" (see linux/gpio/driver.h for its complete definition) with members
+common to each controller of that type:
+
+ - methods to establish GPIO direction
+ - methods used to access GPIO values
+ - method to return the IRQ number associated to a given GPIO
+ - flag saying whether calls to its methods may sleep
+ - optional debugfs dump method (showing extra state like pullup config)
+ - optional base number (will be automatically assigned if omitted)
+ - label for diagnostics and GPIOs mapping using platform data
+
+The code implementing a gpio_chip should support multiple instances of the
+controller, possibly using the driver model. That code will configure each
+gpio_chip and issue gpiochip_add(). Removing a GPIO controller should be rare;
+use gpiochip_remove() when it is unavoidable.
+
+Most often a gpio_chip is part of an instance-specific structure with state not
+exposed by the GPIO interfaces, such as addressing, power management, and more.
+Chips such as codecs will have complex non-GPIO state.
+
+Any debugfs dump method should normally ignore signals which haven't been
+requested as GPIOs. They can use gpiochip_is_requested(), which returns either
+NULL or the label associated with that GPIO when it was requested.
+
+Locking IRQ usage
+-----------------
+Input GPIOs can be used as IRQ signals. When this happens, a driver is requested
+to mark the GPIO as being used as an IRQ:
+
+	int gpiod_lock_as_irq(struct gpio_desc *desc)
+
+This will prevent the use of non-irq related GPIO APIs until the GPIO IRQ lock
+is released:
+
+	void gpiod_unlock_as_irq(struct gpio_desc *desc)
diff --git a/Documentation/gpio.txt b/Documentation/gpio/gpio-legacy.txt
index 6f83fa965b4b..6f83fa965b4b 100644
--- a/Documentation/gpio.txt
+++ b/Documentation/gpio/gpio-legacy.txt
diff --git a/Documentation/gpio/gpio.txt b/Documentation/gpio/gpio.txt
new file mode 100644
index 000000000000..cd9b356e88cd
--- /dev/null
+++ b/Documentation/gpio/gpio.txt
@@ -0,0 +1,119 @@
+GPIO Interfaces
+===============
+
+The documents in this directory give detailed instructions on how to access
+GPIOs in drivers, and how to write a driver for a device that provides GPIOs
+itself.
+
+Due to the history of GPIO interfaces in the kernel, there are two different
+ways to obtain and use GPIOs:
+
+  - The descriptor-based interface is the preferred way to manipulate GPIOs,
+and is described by all the files in this directory excepted gpio-legacy.txt.
+  - The legacy integer-based interface which is considered deprecated (but still
+usable for compatibility reasons) is documented in gpio-legacy.txt.
+
+The remainder of this document applies to the new descriptor-based interface.
+gpio-legacy.txt contains the same information applied to the legacy
+integer-based interface.
+
+
+What is a GPIO?
+===============
+
+A "General Purpose Input/Output" (GPIO) is a flexible software-controlled
+digital signal. They are provided from many kinds of chip, and are familiar
+to Linux developers working with embedded and custom hardware. Each GPIO
+represents a bit connected to a particular pin, or "ball" on Ball Grid Array
+(BGA) packages. Board schematics show which external hardware connects to
+which GPIOs. Drivers can be written generically, so that board setup code
+passes such pin configuration data to drivers.
+
+System-on-Chip (SOC) processors heavily rely on GPIOs. In some cases, every
+non-dedicated pin can be configured as a GPIO; and most chips have at least
+several dozen of them. Programmable logic devices (like FPGAs) can easily
+provide GPIOs; multifunction chips like power managers, and audio codecs
+often have a few such pins to help with pin scarcity on SOCs; and there are
+also "GPIO Expander" chips that connect using the I2C or SPI serial buses.
+Most PC southbridges have a few dozen GPIO-capable pins (with only the BIOS
+firmware knowing how they're used).
+
+The exact capabilities of GPIOs vary between systems. Common options:
+
+  - Output values are writable (high=1, low=0). Some chips also have
+    options about how that value is driven, so that for example only one
+    value might be driven, supporting "wire-OR" and similar schemes for the
+    other value (notably, "open drain" signaling).
+
+  - Input values are likewise readable (1, 0). Some chips support readback
+    of pins configured as "output", which is very useful in such "wire-OR"
+    cases (to support bidirectional signaling). GPIO controllers may have
+    input de-glitch/debounce logic, sometimes with software controls.
+
+  - Inputs can often be used as IRQ signals, often edge triggered but
+    sometimes level triggered. Such IRQs may be configurable as system
+    wakeup events, to wake the system from a low power state.
+
+  - Usually a GPIO will be configurable as either input or output, as needed
+    by different product boards; single direction ones exist too.
+
+  - Most GPIOs can be accessed while holding spinlocks, but those accessed
+    through a serial bus normally can't. Some systems support both types.
+
+On a given board each GPIO is used for one specific purpose like monitoring
+MMC/SD card insertion/removal, detecting card write-protect status, driving
+a LED, configuring a transceiver, bit-banging a serial bus, poking a hardware
+watchdog, sensing a switch, and so on.
+
+
+Common GPIO Properties
+======================
+
+These properties are met through all the other documents of the GPIO interface
+and it is useful to understand them, especially if you need to define GPIO
+mappings.
+
+Active-High and Active-Low
+--------------------------
+It is natural to assume that a GPIO is "active" when its output signal is 1
+("high"), and inactive when it is 0 ("low"). However in practice the signal of a
+GPIO may be inverted before is reaches its destination, or a device could decide
+to have different conventions about what "active" means. Such decisions should
+be transparent to device drivers, therefore it is possible to define a GPIO as
+being either active-high ("1" means "active", the default) or active-low ("0"
+means "active") so that drivers only need to worry about the logical signal and
+not about what happens at the line level.
+
+Open Drain and Open Source
+--------------------------
+Sometimes shared signals need to use "open drain" (where only the low signal
+level is actually driven), or "open source" (where only the high signal level is
+driven) signaling. That term applies to CMOS transistors; "open collector" is
+used for TTL. A pullup or pulldown resistor causes the high or low signal level.
+This is sometimes called a "wire-AND"; or more practically, from the negative
+logic (low=true) perspective this is a "wire-OR".
+
+One common example of an open drain signal is a shared active-low IRQ line.
+Also, bidirectional data bus signals sometimes use open drain signals.
+
+Some GPIO controllers directly support open drain and open source outputs; many
+don't. When you need open drain signaling but your hardware doesn't directly
+support it, there's a common idiom you can use to emulate it with any GPIO pin
+that can be used as either an input or an output:
+
+ LOW:	gpiod_direction_output(gpio, 0) ... this drives the signal and overrides
+	the pullup.
+
+ HIGH:	gpiod_direction_input(gpio) ... this turns off the output, so the pullup
+	(or some other device) controls the signal.
+
+The same logic can be applied to emulate open source signaling, by driving the
+high signal and configuring the GPIO as input for low. This open drain/open
+source emulation can be handled transparently by the GPIO framework.
+
+If you are "driving" the signal high but gpiod_get_value(gpio) reports a low
+value (after the appropriate rise time passes), you know some other component is
+driving the shared signal low. That's not necessarily an error. As one common
+example, that's how I2C clocks are stretched:  a slave that needs a slower clock
+delays the rising edge of SCK, and the I2C master adjusts its signaling rate
+accordingly.
diff --git a/Documentation/gpio/sysfs.txt b/Documentation/gpio/sysfs.txt
new file mode 100644
index 000000000000..c2c3a97f8ff7
--- /dev/null
+++ b/Documentation/gpio/sysfs.txt
@@ -0,0 +1,155 @@
+GPIO Sysfs Interface for Userspace
+==================================
+
+Platforms which use the "gpiolib" implementors framework may choose to
+configure a sysfs user interface to GPIOs. This is different from the
+debugfs interface, since it provides control over GPIO direction and
+value instead of just showing a gpio state summary. Plus, it could be
+present on production systems without debugging support.
+
+Given appropriate hardware documentation for the system, userspace could
+know for example that GPIO #23 controls the write protect line used to
+protect boot loader segments in flash memory. System upgrade procedures
+may need to temporarily remove that protection, first importing a GPIO,
+then changing its output state, then updating the code before re-enabling
+the write protection. In normal use, GPIO #23 would never be touched,
+and the kernel would have no need to know about it.
+
+Again depending on appropriate hardware documentation, on some systems
+userspace GPIO can be used to determine system configuration data that
+standard kernels won't know about. And for some tasks, simple userspace
+GPIO drivers could be all that the system really needs.
+
+Note that standard kernel drivers exist for common "LEDs and Buttons"
+GPIO tasks:  "leds-gpio" and "gpio_keys", respectively. Use those
+instead of talking directly to the GPIOs; they integrate with kernel
+frameworks better than your userspace code could.
+
+
+Paths in Sysfs
+--------------
+There are three kinds of entry in /sys/class/gpio:
+
+   -	Control interfaces used to get userspace control over GPIOs;
+
+   -	GPIOs themselves; and
+
+   -	GPIO controllers ("gpio_chip" instances).
+
+That's in addition to standard files including the "device" symlink.
+
+The control interfaces are write-only:
+
+    /sys/class/gpio/
+
+    	"export" ... Userspace may ask the kernel to export control of
+		a GPIO to userspace by writing its number to this file.
+
+		Example:  "echo 19 > export" will create a "gpio19" node
+		for GPIO #19, if that's not requested by kernel code.
+
+    	"unexport" ... Reverses the effect of exporting to userspace.
+
+		Example:  "echo 19 > unexport" will remove a "gpio19"
+		node exported using the "export" file.
+
+GPIO signals have paths like /sys/class/gpio/gpio42/ (for GPIO #42)
+and have the following read/write attributes:
+
+    /sys/class/gpio/gpioN/
+
+	"direction" ... reads as either "in" or "out". This value may
+		normally be written. Writing as "out" defaults to
+		initializing the value as low. To ensure glitch free
+		operation, values "low" and "high" may be written to
+		configure the GPIO as an output with that initial value.
+
+		Note that this attribute *will not exist* if the kernel
+		doesn't support changing the direction of a GPIO, or
+		it was exported by kernel code that didn't explicitly
+		allow userspace to reconfigure this GPIO's direction.
+
+	"value" ... reads as either 0 (low) or 1 (high). If the GPIO
+		is configured as an output, this value may be written;
+		any nonzero value is treated as high.
+
+		If the pin can be configured as interrupt-generating interrupt
+		and if it has been configured to generate interrupts (see the
+		description of "edge"), you can poll(2) on that file and
+		poll(2) will return whenever the interrupt was triggered. If
+		you use poll(2), set the events POLLPRI and POLLERR. If you
+		use select(2), set the file descriptor in exceptfds. After
+		poll(2) returns, either lseek(2) to the beginning of the sysfs
+		file and read the new value or close the file and re-open it
+		to read the value.
+
+	"edge" ... reads as either "none", "rising", "falling", or
+		"both". Write these strings to select the signal edge(s)
+		that will make poll(2) on the "value" file return.
+
+		This file exists only if the pin can be configured as an
+		interrupt generating input pin.
+
+	"active_low" ... reads as either 0 (false) or 1 (true). Write
+		any nonzero value to invert the value attribute both
+		for reading and writing. Existing and subsequent
+		poll(2) support configuration via the edge attribute
+		for "rising" and "falling" edges will follow this
+		setting.
+
+GPIO controllers have paths like /sys/class/gpio/gpiochip42/ (for the
+controller implementing GPIOs starting at #42) and have the following
+read-only attributes:
+
+    /sys/class/gpio/gpiochipN/
+
+    	"base" ... same as N, the first GPIO managed by this chip
+
+    	"label" ... provided for diagnostics (not always unique)
+
+    	"ngpio" ... how many GPIOs this manges (N to N + ngpio - 1)
+
+Board documentation should in most cases cover what GPIOs are used for
+what purposes. However, those numbers are not always stable; GPIOs on
+a daughtercard might be different depending on the base board being used,
+or other cards in the stack. In such cases, you may need to use the
+gpiochip nodes (possibly in conjunction with schematics) to determine
+the correct GPIO number to use for a given signal.
+
+
+Exporting from Kernel code
+--------------------------
+Kernel code can explicitly manage exports of GPIOs which have already been
+requested using gpio_request():
+
+	/* export the GPIO to userspace */
+	int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
+
+	/* reverse gpio_export() */
+	void gpiod_unexport(struct gpio_desc *desc);
+
+	/* create a sysfs link to an exported GPIO node */
+	int gpiod_export_link(struct device *dev, const char *name,
+		      struct gpio_desc *desc);
+
+	/* change the polarity of a GPIO node in sysfs */
+	int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value);
+
+After a kernel driver requests a GPIO, it may only be made available in
+the sysfs interface by gpiod_export(). The driver can control whether the
+signal direction may change. This helps drivers prevent userspace code
+from accidentally clobbering important system state.
+
+This explicit exporting can help with debugging (by making some kinds
+of experiments easier), or can provide an always-there interface that's
+suitable for documenting as part of a board support package.
+
+After the GPIO has been exported, gpiod_export_link() allows creating
+symlinks from elsewhere in sysfs to the GPIO sysfs node. Drivers can
+use this to provide the interface under their own device in sysfs with
+a descriptive name.
+
+Drivers can use gpiod_sysfs_set_active_low() to hide GPIO line polarity
+differences between boards from user space. Polarity change can be done both
+before and after gpiod_export(), and previously enabled poll(2) support for
+either rising or falling edge will be reconfigured to follow this setting.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e06e99303dd3..d7e736c53e51 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1535,6 +1535,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 			* atapi_dmadir: Enable ATAPI DMADIR bridge support
 
+			* disable: Disable this device.
+
 			If there are multiple matching configurations changing
 			the same attribute, the last one is used.
 
diff --git a/Documentation/mic/mpssd/mpssd.c b/Documentation/mic/mpssd/mpssd.c
index 0c980ad40b17..4d17487d5ad9 100644
--- a/Documentation/mic/mpssd/mpssd.c
+++ b/Documentation/mic/mpssd/mpssd.c
@@ -313,7 +313,7 @@ static struct mic_device_desc *get_device_desc(struct mic_info *mic, int type)
 	int i;
 	void *dp = get_dp(mic, type);
 
-	for (i = mic_aligned_size(struct mic_bootparam); i < PAGE_SIZE;
+	for (i = sizeof(struct mic_bootparam); i < PAGE_SIZE;
 		i += mic_total_desc_size(d)) {
 		d = dp + i;
 
@@ -445,8 +445,8 @@ init_vr(struct mic_info *mic, int fd, int type,
 		__func__, mic->name, vr0->va, vr0->info, vr_size,
 		vring_size(MIC_VRING_ENTRIES, MIC_VIRTIO_RING_ALIGN));
 	mpsslog("magic 0x%x expected 0x%x\n",
-		vr0->info->magic, MIC_MAGIC + type);
-	assert(vr0->info->magic == MIC_MAGIC + type);
+		le32toh(vr0->info->magic), MIC_MAGIC + type);
+	assert(le32toh(vr0->info->magic) == MIC_MAGIC + type);
 	if (vr1) {
 		vr1->va = (struct mic_vring *)
 			&va[MIC_DEVICE_PAGE_END + vr_size];
@@ -458,8 +458,8 @@ init_vr(struct mic_info *mic, int fd, int type,
 			__func__, mic->name, vr1->va, vr1->info, vr_size,
 			vring_size(MIC_VRING_ENTRIES, MIC_VIRTIO_RING_ALIGN));
 		mpsslog("magic 0x%x expected 0x%x\n",
-			vr1->info->magic, MIC_MAGIC + type + 1);
-		assert(vr1->info->magic == MIC_MAGIC + type + 1);
+			le32toh(vr1->info->magic), MIC_MAGIC + type + 1);
+		assert(le32toh(vr1->info->magic) == MIC_MAGIC + type + 1);
 	}
 done:
 	return va;
@@ -520,7 +520,7 @@ static void *
 virtio_net(void *arg)
 {
 	static __u8 vnet_hdr[2][sizeof(struct virtio_net_hdr)];
-	static __u8 vnet_buf[2][MAX_NET_PKT_SIZE] __aligned(64);
+	static __u8 vnet_buf[2][MAX_NET_PKT_SIZE] __attribute__ ((aligned(64)));
 	struct iovec vnet_iov[2][2] = {
 		{ { .iov_base = vnet_hdr[0], .iov_len = sizeof(vnet_hdr[0]) },
 		  { .iov_base = vnet_buf[0], .iov_len = sizeof(vnet_buf[0]) } },
@@ -1412,6 +1412,12 @@ mic_config(void *arg)
 	}
 
 	do {
+		ret = lseek(fd, 0, SEEK_SET);
+		if (ret < 0) {
+			mpsslog("%s: Failed to seek to file start '%s': %s\n",
+				mic->name, pathname, strerror(errno));
+			goto close_error1;
+		}
 		ret = read(fd, value, sizeof(value));
 		if (ret < 0) {
 			mpsslog("%s: Failed to read sysfs entry '%s': %s\n",
diff --git a/Documentation/module-signing.txt b/Documentation/module-signing.txt
new file mode 100644
index 000000000000..2b40e04d3c49
--- /dev/null
+++ b/Documentation/module-signing.txt
@@ -0,0 +1,240 @@
+			==============================
+			KERNEL MODULE SIGNING FACILITY
+			==============================
+
+CONTENTS
+
+ - Overview.
+ - Configuring module signing.
+ - Generating signing keys.
+ - Public keys in the kernel.
+ - Manually signing modules.
+ - Signed modules and stripping.
+ - Loading signed modules.
+ - Non-valid signatures and unsigned modules.
+ - Administering/protecting the private key.
+
+
+========
+OVERVIEW
+========
+
+The kernel module signing facility cryptographically signs modules during
+installation and then checks the signature upon loading the module.  This
+allows increased kernel security by disallowing the loading of unsigned modules
+or modules signed with an invalid key.  Module signing increases security by
+making it harder to load a malicious module into the kernel.  The module
+signature checking is done by the kernel so that it is not necessary to have
+trusted userspace bits.
+
+This facility uses X.509 ITU-T standard certificates to encode the public keys
+involved.  The signatures are not themselves encoded in any industrial standard
+type.  The facility currently only supports the RSA public key encryption
+standard (though it is pluggable and permits others to be used).  The possible
+hash algorithms that can be used are SHA-1, SHA-224, SHA-256, SHA-384, and
+SHA-512 (the algorithm is selected by data in the signature).
+
+
+==========================
+CONFIGURING MODULE SIGNING
+==========================
+
+The module signing facility is enabled by going to the "Enable Loadable Module
+Support" section of the kernel configuration and turning on
+
+	CONFIG_MODULE_SIG	"Module signature verification"
+
+This has a number of options available:
+
+ (1) "Require modules to be validly signed" (CONFIG_MODULE_SIG_FORCE)
+
+     This specifies how the kernel should deal with a module that has a
+     signature for which the key is not known or a module that is unsigned.
+
+     If this is off (ie. "permissive"), then modules for which the key is not
+     available and modules that are unsigned are permitted, but the kernel will
+     be marked as being tainted.
+
+     If this is on (ie. "restrictive"), only modules that have a valid
+     signature that can be verified by a public key in the kernel's possession
+     will be loaded.  All other modules will generate an error.
+
+     Irrespective of the setting here, if the module has a signature block that
+     cannot be parsed, it will be rejected out of hand.
+
+
+ (2) "Automatically sign all modules" (CONFIG_MODULE_SIG_ALL)
+
+     If this is on then modules will be automatically signed during the
+     modules_install phase of a build.  If this is off, then the modules must
+     be signed manually using:
+
+	scripts/sign-file
+
+
+ (3) "Which hash algorithm should modules be signed with?"
+
+     This presents a choice of which hash algorithm the installation phase will
+     sign the modules with:
+
+	CONFIG_SIG_SHA1		"Sign modules with SHA-1"
+	CONFIG_SIG_SHA224	"Sign modules with SHA-224"
+	CONFIG_SIG_SHA256	"Sign modules with SHA-256"
+	CONFIG_SIG_SHA384	"Sign modules with SHA-384"
+	CONFIG_SIG_SHA512	"Sign modules with SHA-512"
+
+     The algorithm selected here will also be built into the kernel (rather
+     than being a module) so that modules signed with that algorithm can have
+     their signatures checked without causing a dependency loop.
+
+
+=======================
+GENERATING SIGNING KEYS
+=======================
+
+Cryptographic keypairs are required to generate and check signatures.  A
+private key is used to generate a signature and the corresponding public key is
+used to check it.  The private key is only needed during the build, after which
+it can be deleted or stored securely.  The public key gets built into the
+kernel so that it can be used to check the signatures as the modules are
+loaded.
+
+Under normal conditions, the kernel build will automatically generate a new
+keypair using openssl if one does not exist in the files:
+
+	signing_key.priv
+	signing_key.x509
+
+during the building of vmlinux (the public part of the key needs to be built
+into vmlinux) using parameters in the:
+
+	x509.genkey
+
+file (which is also generated if it does not already exist).
+
+It is strongly recommended that you provide your own x509.genkey file.
+
+Most notably, in the x509.genkey file, the req_distinguished_name section
+should be altered from the default:
+
+	[ req_distinguished_name ]
+	O = Magrathea
+	CN = Glacier signing key
+	emailAddress = slartibartfast@magrathea.h2g2
+
+The generated RSA key size can also be set with:
+
+	[ req ]
+	default_bits = 4096
+
+
+It is also possible to manually generate the key private/public files using the
+x509.genkey key generation configuration file in the root node of the Linux
+kernel sources tree and the openssl command.  The following is an example to
+generate the public/private key files:
+
+	openssl req -new -nodes -utf8 -sha256 -days 36500 -batch -x509 \
+	   -config x509.genkey -outform DER -out signing_key.x509 \
+	   -keyout signing_key.priv
+
+
+=========================
+PUBLIC KEYS IN THE KERNEL
+=========================
+
+The kernel contains a ring of public keys that can be viewed by root.  They're
+in a keyring called ".system_keyring" that can be seen by:
+
+	[root@deneb ~]# cat /proc/keys
+	...
+	223c7853 I------     1 perm 1f030000     0     0 keyring   .system_keyring: 1
+	302d2d52 I------     1 perm 1f010000     0     0 asymmetri Fedora kernel signing key: d69a84e6bce3d216b979e9505b3e3ef9a7118079: X509.RSA a7118079 []
+	...
+
+Beyond the public key generated specifically for module signing, any file
+placed in the kernel source root directory or the kernel build root directory
+whose name is suffixed with ".x509" will be assumed to be an X.509 public key
+and will be added to the keyring.
+
+Further, the architecture code may take public keys from a hardware store and
+add those in also (e.g. from the UEFI key database).
+
+Finally, it is possible to add additional public keys by doing:
+
+	keyctl padd asymmetric "" [.system_keyring-ID] <[key-file]
+
+e.g.:
+
+	keyctl padd asymmetric "" 0x223c7853 <my_public_key.x509
+
+Note, however, that the kernel will only permit keys to be added to
+.system_keyring _if_ the new key's X.509 wrapper is validly signed by a key
+that is already resident in the .system_keyring at the time the key was added.
+
+
+=========================
+MANUALLY SIGNING MODULES
+=========================
+
+To manually sign a module, use the scripts/sign-file tool available in
+the Linux kernel source tree.  The script requires 4 arguments:
+
+	1.  The hash algorithm (e.g., sha256)
+	2.  The private key filename
+	3.  The public key filename
+	4.  The kernel module to be signed
+
+The following is an example to sign a kernel module:
+
+	scripts/sign-file sha512 kernel-signkey.priv \
+		kernel-signkey.x509 module.ko
+
+The hash algorithm used does not have to match the one configured, but if it
+doesn't, you should make sure that hash algorithm is either built into the
+kernel or can be loaded without requiring itself.
+
+
+============================
+SIGNED MODULES AND STRIPPING
+============================
+
+A signed module has a digital signature simply appended at the end.  The string
+"~Module signature appended~." at the end of the module's file confirms that a
+signature is present but it does not confirm that the signature is valid!
+
+Signed modules are BRITTLE as the signature is outside of the defined ELF
+container.  Thus they MAY NOT be stripped once the signature is computed and
+attached.  Note the entire module is the signed payload, including any and all
+debug information present at the time of signing.
+
+
+======================
+LOADING SIGNED MODULES
+======================
+
+Modules are loaded with insmod, modprobe, init_module() or finit_module(),
+exactly as for unsigned modules as no processing is done in userspace.  The
+signature checking is all done within the kernel.
+
+
+=========================================
+NON-VALID SIGNATURES AND UNSIGNED MODULES
+=========================================
+
+If CONFIG_MODULE_SIG_FORCE is enabled or enforcemodulesig=1 is supplied on
+the kernel command line, the kernel will only load validly signed modules
+for which it has a public key.   Otherwise, it will also load modules that are
+unsigned.   Any module for which the kernel has a key, but which proves to have
+a signature mismatch will not be permitted to load.
+
+Any module that has an unparseable signature will be rejected.
+
+
+=========================================
+ADMINISTERING/PROTECTING THE PRIVATE KEY
+=========================================
+
+Since the private key is used to sign modules, viruses and malware could use
+the private key to sign modules and compromise the operating system.  The
+private key must be either destroyed or moved to a secure location and not kept
+in the root node of the kernel source tree.
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 3c12d9a7ed00..8a984e994e61 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -16,8 +16,12 @@ ip_default_ttl - INTEGER
 	Default: 64 (as recommended by RFC1700)
 
 ip_no_pmtu_disc - BOOLEAN
-	Disable Path MTU Discovery.
-	default FALSE
+	Disable Path MTU Discovery. If enabled and a
+	fragmentation-required ICMP is received, the PMTU to this
+	destination will be set to min_pmtu (see below). You will need
+	to raise min_pmtu to the smallest interface MTU on your system
+	manually if you want to avoid locally generated fragments.
+	Default: FALSE
 
 min_pmtu - INTEGER
 	default 552 - minimum discovered Path MTU
diff --git a/Documentation/networking/packet_mmap.txt b/Documentation/networking/packet_mmap.txt
index c01223628a87..8e48e3b14227 100644
--- a/Documentation/networking/packet_mmap.txt
+++ b/Documentation/networking/packet_mmap.txt
@@ -123,6 +123,16 @@ Transmission process is similar to capture as shown below.
 [shutdown]  close() --------> destruction of the transmission socket and
                               deallocation of all associated resources.
 
+Socket creation and destruction is also straight forward, and is done
+the same way as in capturing described in the previous paragraph:
+
+ int fd = socket(PF_PACKET, mode, 0);
+
+The protocol can optionally be 0 in case we only want to transmit
+via this socket, which avoids an expensive call to packet_rcv().
+In this case, you also need to bind(2) the TX_RING with sll_protocol = 0
+set. Otherwise, htons(ETH_P_ALL) or any other protocol, for example.
+
 Binding the socket to your network interface is mandatory (with zero copy) to
 know the header size of frames used in the circular buffer.