diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/arm/freescale.txt | 7 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/arm/genesi.txt | 8 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/arm/l2cc.txt | 44 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/arm/primecell.txt | 4 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/arm/samsung.txt | 9 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/pl061-gpio.txt | 10 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/spi/spi_pl022.txt | 12 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/vendor-prefixes.txt | 40 | ||||
| -rw-r--r-- | Documentation/devicetree/usage-model | 403 | ||||
| -rw-r--r-- | Documentation/hwmon/exynos4_tmu | 81 | ||||
| -rw-r--r-- | Documentation/hwspinlock.txt | 18 | ||||
| -rw-r--r-- | Documentation/power/runtime_pm.txt | 10 | ||||
| -rw-r--r-- | Documentation/sound/alsa/HD-Audio-Models.txt | 1 | ||||
| -rw-r--r-- | Documentation/stable_kernel_rules.txt | 14 | ||||
| -rw-r--r-- | Documentation/thermal/cpu-cooling-api.txt | 52 | ||||
| -rw-r--r-- | Documentation/thermal/sysfs-api.txt | 4 |
16 files changed, 696 insertions, 21 deletions
diff --git a/Documentation/devicetree/bindings/arm/freescale.txt b/Documentation/devicetree/bindings/arm/freescale.txt new file mode 100644 index 00000000000..8c52102b225 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/freescale.txt @@ -0,0 +1,7 @@ +mx51 "Babbage" evalutation board +Required root node properties: + - compatible = "fsl,mx51-babbage", "fsl,mx51"; + +mx53 "Loco" evaluation board +Required root node properties: + - compatible = "fsl,mx53-loco", "fsl,mx53"; diff --git a/Documentation/devicetree/bindings/arm/genesi.txt b/Documentation/devicetree/bindings/arm/genesi.txt new file mode 100644 index 00000000000..b353489acd4 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/genesi.txt @@ -0,0 +1,8 @@ +Genesi EfikaMX based on Freescale mx51 +Required root node properties: + - compatible = "genesi,efikamx", "fsl,mx51"; + +Genesi EfikaMX Smartbook based on Freescale mx51 +Required root node properties: + - compatible = "genesi,efikasb", "fsl,mx51"; + diff --git a/Documentation/devicetree/bindings/arm/l2cc.txt b/Documentation/devicetree/bindings/arm/l2cc.txt new file mode 100644 index 00000000000..7ca52161e7a --- /dev/null +++ b/Documentation/devicetree/bindings/arm/l2cc.txt @@ -0,0 +1,44 @@ +* ARM L2 Cache Controller + +ARM cores often have a separate level 2 cache controller. There are various +implementations of the L2 cache controller with compatible programming models. +The ARM L2 cache representation in the device tree should be done as follows: + +Required properties: + +- compatible : should be one of: + "arm,pl310-cache" + "arm,l220-cache" + "arm,l210-cache" +- cache-unified : Specifies the cache is a unified cache. +- cache-level : Should be set to 2 for a level 2 cache. +- reg : Physical base address and size of cache controller's memory mapped + registers. + +Optional properties: + +- arm,data-latency : Cycles of latency for Data RAM accesses. Specifies 3 cells of + read, write and setup latencies. Minimum valid values are 1. Controllers + without setup latency control should use a value of 0. +- arm,tag-latency : Cycles of latency for Tag RAM accesses. Specifies 3 cells of + read, write and setup latencies. Controllers without setup latency control + should use 0. Controllers without separate read and write Tag RAM latency + values should only use the first cell. +- arm,dirty-latency : Cycles of latency for Dirty RAMs. This is a single cell. +- arm,filter-ranges : <start length> Starting address and length of window to + filter. Addresses in the filter window are directed to the M1 port. Other + addresses will go to the M0 port. +- interrupts : 1 combined interrupt. + +Example: + +L2: cache-controller { + compatible = "arm,pl310-cache"; + reg = <0xfff12000 0x1000>; + arm,data-latency = <1 1 1>; + arm,tag-latency = <2 2 2>; + arm,filter-latency = <0x80000000 0x8000000>; + cache-unified; + cache-level = <2>; + interrupts = <45>; +}; diff --git a/Documentation/devicetree/bindings/arm/primecell.txt b/Documentation/devicetree/bindings/arm/primecell.txt index 1d5d7a870ec..951ca46789d 100644 --- a/Documentation/devicetree/bindings/arm/primecell.txt +++ b/Documentation/devicetree/bindings/arm/primecell.txt @@ -6,7 +6,9 @@ driver matching. Required properties: -- compatible : should be a specific value for peripheral and "arm,primecell" +- compatible : should be a specific name for the peripheral and + "arm,primecell". The specific name will match the ARM + engineering name for the logic block in the form: "arm,pl???" Optional properties: diff --git a/Documentation/devicetree/bindings/arm/samsung.txt b/Documentation/devicetree/bindings/arm/samsung.txt new file mode 100644 index 00000000000..594cb97e3d8 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/samsung.txt @@ -0,0 +1,9 @@ +Samsung Exynos4 S5PV310 SoC based SMDKV310 eval board + + SMDKV310 eval board is based on S5PV310 SoC which belongs to + Samsung's Exynos4 family of application processors. + +Required root node properties: + - compatible = "samsung,smdkv310","samsung,s5pv310" + (a) "samsung,smdkv310" - for Samsung's SMDKV310 eval board. + (b) "samsung,s5pv310" - for boards based on S5PV310 SoC. diff --git a/Documentation/devicetree/bindings/gpio/pl061-gpio.txt b/Documentation/devicetree/bindings/gpio/pl061-gpio.txt new file mode 100644 index 00000000000..a2c416bcbcc --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/pl061-gpio.txt @@ -0,0 +1,10 @@ +ARM PL061 GPIO controller + +Required properties: +- compatible : "arm,pl061", "arm,primecell" +- #gpio-cells : Should be two. The first cell is the pin number and the + second cell is used to specify optional parameters: + - bit 0 specifies polarity (0 for normal, 1 for inverted) +- gpio-controller : Marks the device node as a GPIO controller. +- interrupts : Interrupt mapping for GPIO IRQ. + diff --git a/Documentation/devicetree/bindings/spi/spi_pl022.txt b/Documentation/devicetree/bindings/spi/spi_pl022.txt new file mode 100644 index 00000000000..306ec3ff3c0 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi_pl022.txt @@ -0,0 +1,12 @@ +ARM PL022 SPI controller + +Required properties: +- compatible : "arm,pl022", "arm,primecell" +- reg : Offset and length of the register set for the device +- interrupts : Should contain SPI controller interrupt + +Optional properties: +- cs-gpios : should specify GPIOs used for chipselects. + The gpios will be referred to as reg = <index> in the SPI child nodes. + If unspecified, a single SPI device without a chip select can be used. + diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt new file mode 100644 index 00000000000..e8552782b44 --- /dev/null +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt @@ -0,0 +1,40 @@ +Device tree binding vendor prefix registry. Keep list in alphabetical order. + +This isn't an exhaustive list, but you should add new prefixes to it before +using them to avoid name-space collisions. + +adi Analog Devices, Inc. +amcc Applied Micro Circuits Corporation (APM, formally AMCC) +apm Applied Micro Circuits Corporation (APM) +arm ARM Ltd. +atmel Atmel Corporation +chrp Common Hardware Reference Platform +dallas Maxim Integrated Products (formerly Dallas Semiconductor) +denx Denx Software Engineering +epson Seiko Epson Corp. +est ESTeem Wireless Modems +fsl Freescale Semiconductor +GEFanuc GE Fanuc Intelligent Platforms Embedded Systems, Inc. +gef GE Fanuc Intelligent Platforms Embedded Systems, Inc. +hp Hewlett Packard +ibm International Business Machines (IBM) +idt Integrated Device Technologies, Inc. +intercontrol Inter Control Group +linux Linux-specific binding +marvell Marvell Technology Group Ltd. +maxim Maxim Integrated Products +mosaixtech Mosaix Technologies, Inc. +national National Semiconductor +nintendo Nintendo +nvidia NVIDIA +nxp NXP Semiconductors +powervr Imagination Technologies +qcom Qualcomm, Inc. +ramtron Ramtron International +samsung Samsung Semiconductor +schindler Schindler +simtek +sirf SiRF Technology, Inc. +stericsson ST-Ericsson +ti Texas Instruments +xlnx Xilinx diff --git a/Documentation/devicetree/usage-model b/Documentation/devicetree/usage-model new file mode 100644 index 00000000000..45e03b8dd04 --- /dev/null +++ b/Documentation/devicetree/usage-model @@ -0,0 +1,403 @@ +Linux and the Device Tree +The Linux usage model for device tree data + +Author: Grant Likely <grant.likely@secretlab.ca> + +This article describes how Linux uses the device tree. An overview of +the device tree data format can be found at the <a +href="http://devicetree.org/Device_Tree_Usage">Device Tree Usage</a> +page on <a href="http://devicetree.org">devicetree.org</a>. + + + All the cool architectures are using device tree. I want to + use device tree too! + +The "Open Firmware Device Tree", or simply Device Tree (DT), is a data +structure and language for describing hardware. More specifically, it +is a description of hardware that is readable by an operating system +so that the operating system doesn't need to hard code details of the +machine. + +Structurally, the DT is a tree, or acyclic graph with named nodes, and +nodes may have an arbitrary number of named properties encapsulating +arbitrary data. A mechanism also exists to create arbitrary +links from one node to another outside of the natural tree structure. + +Conceptually, a common set of usage conventions, called 'bindings', +is defined for how data should appear in the tree to describe typical +hardware characteristics including data busses, interrupt lines, GPIO +connections, and peripheral devices. + +As much as possible, hardware is described using existing bindings to +maximize use of existing support code, but since property and node +names are simply text strings, it is easy to extend existing bindings +or create new ones by defining new nodes and properties. + +<h2>History</h2> +The DT was originally created by Open Firmware as part of the +communication method for passing data from Open Firmware to a client +program (like to an operating system). An operating system used the +Device Tree to discover the topology of the hardware at runtime, and +thereby support a majority of available hardware without hard coded +information (assuming drivers were available for all devices). + +Since Open Firmware is commonly used on PowerPC and SPARC platforms, +the Linux support for those architectures has for a long time used the +Device Tree. + +In 2005, when PowerPC Linux began a major cleanup and to merge 32-bit +and 64-bit support, the decision was made to require DT support on all +powerpc platforms, regardless of whether or not they used Open +Firmware. To do this, a DT representation called the Flattened Device +Tree (FDT) was created which could be passed to the kernel as a binary +blob without requiring a real Open Firmware implementation. U-Boot, +kexec, and other bootloaders were modified to support both passing a +Device Tree Binary (dtb) and to modify a dtb at boot time. + +Some time later, FDT infrastructure was generalized to be usable by +all architectures. At the time of this writing, 6 mainlined +architectures (arm, microblaze, mips, powerpc, sparc, and x86) and 1 +out of mainline (nios) have some level of DT support. + +<h2>Data Model</h2> +If you haven't already read the +href="http://devicetree.org/Device_Tree_Usage">Device Tree Usage</a> +page, then go read it now. It's okay, I'll wait.... + +<h3>High Level View</h3> +The most important thing to understand is that the DT is simply a data +structure that describes the hardware. There is nothing magical about +it, and it doesn't magically make all hardware configuration problems +go away. What it does do is provide a language for decoupling the +hardware configuration from the board and device driver support in the +Linux kernel (or any other operating system for that matter). Using +it allows board and device support to become data driven; to make +setup decisions based on data passed into the kernel instead of on +per-machine hard coded selections. + +Ideally, data driven platform setup should result in less code +duplication and make it easier to support a wide range of hardware +with a single kernel image. + +Linux uses DT data for three major purposes: +1) platform identification, +2) runtime configuration, and +3) device population. + +<h4>Platform Identification</h4> +First and foremost, the kernel will use data in the DT to identify the +specific machine. In a perfect world, the specific platform shouldn't +matter to the kernel because all platform details would be described +perfectly by the device tree in a consistent and reliable manner. +Hardware is not perfect though, and so the kernel must identify the +machine during early boot so that it has the opportunity to run +machine-specific fixups. + +In the majority of cases, the machine identity is irrelevant, and the +kernel will instead select setup code based on the machine's core +CPU or SoC. On ARM for example, setup_arch() in +arch/arm/kernel/setup.c will call setup_machine_fdt() in +arch/arm/kernel/devicetree.c which searches through the machine_desc +table and selects the machine_desc which best matches the device tree +data. It determines the best match by looking at the 'compatible' +property in the root device tree node, and comparing it with the +dt_compat list in struct machine_desc. + +The 'compatible' property contains a sorted list of strings starting +with the exact name of the machine, followed by an optional list of +boards it is compatible with sorted from most compatible to least. For +example, the root compatible properties for the TI BeagleBoard and its +successor, the BeagleBoard xM board might look like: + + compatible = "ti,omap3-beagleboard", "ti,omap3450", "ti,omap3"; + compatible = "ti,omap3-beagleboard-xm", "ti,omap3450", "ti,omap3"; + +Where "ti,omap3-beagleboard-xm" specifies the exact model, it also +claims that it compatible with the OMAP 3450 SoC, and the omap3 family +of SoCs in general. You'll notice that the list is sorted from most +specific (exact board) to least specific (SoC family). + +Astute readers might point out that the Beagle xM could also claim +compatibility with the original Beagle board. However, one should be +cautioned about doing so at the board level since there is typically a +high level of change from one board to another, even within the same +product line, and it is hard to nail down exactly what is meant when one +board claims to be compatible with another. For the top level, it is +better to err on the side of caution and not claim one board is +compatible with another. The notable exception would be when one +board is a carrier for another, such as a CPU module attached to a +carrier board. + +One more note on compatible values. Any string used in a compatible +property must be documented as to what it indicates. Add +documentation for compatible strings in Documentation/devicetree/bindings. + +Again on ARM, for each machine_desc, the kernel looks to see if +any of the dt_compat list entries appear in the compatible property. +If one does, then that machine_desc is a candidate for driving the +machine. After searching the entire table of machine_descs, +setup_machine_fdt() returns the 'most compatible' machine_desc based +on which entry in the compatible property each machine_desc matches +against. If no matching machine_desc is found, then it returns NULL. + +The reasoning behind this scheme is the observation that in the majority +of cases, a single machine_desc can support a large number of boards +if they all use the same SoC, or same family of SoCs. However, +invariably there will be some exceptions where a specific board will +require special setup code that is not useful in the generic case. +Special cases could be handled by explicitly checking for the +troublesome board(s) in generic setup code, but doing so very quickly +becomes ugly and/or unmaintainable if it is more than just a couple of +cases. + +Instead, the compatible list allows a generic machine_desc to provide +support for a wide common set of boards by specifying "less +compatible" value in the dt_compat list. In the example above, +generic board support can claim compatibility with "ti,omap3" or +"ti,omap3450". If a bug was discovered on the original beagleboard +that required special workaround code during early boot, then a new +machine_desc could be added which implements the workarounds and only +matches on "ti,omap3-beagleboard". + +PowerPC uses a slightly different scheme where it calls the .probe() +hook from each machine_desc, and the first one returning TRUE is used. +However, this approach does not take into account the priority of the +compatible list, and probably should be avoided for new architecture +support. + +<h4>Runtime configuration</h4> +In most cases, a DT will be the sole method of communicating data from +firmware to the kernel, so also gets used to pass in runtime and +configuration data like the kernel parameters string and the location +of an initrd image. + +Most of this data is contained in the /chosen node, and when booting +Linux it will look something like this: + + chosen { + bootargs = "console=ttyS0,115200 loglevel=8"; + initrd-start = <0xc8000000>; + initrd-end = <0xc8200000>; + }; + +The bootargs property contains the kernel arguments, and the initrd-* +properties define the address and size of an initrd blob. The +chosen node may also optionally contain an arbitrary number of +additional properties for platform-specific configuration data. + +During early boot, the architecture setup code calls of_scan_flat_dt() +several times with different helper callbacks to parse device tree +data before paging is setup. The of_scan_flat_dt() code scans through +the device tree and uses the helpers to extract information required +during early boot. Typically the early_init_dt_scan_chosen() helper +is used to parse the chosen node including kernel parameters, +early_init_dt_scan_root() to initialize the DT address space model, +and early_init_dt_scan_memory() to determine the size and +location of usable RAM. + +On ARM, the function setup_machine_fdt() is responsible for early +scanning of the device tree after selecting the correct machine_desc +that supports the board. + +<h4>Device population</h4> +After the board has been identified, and after the early configuration data +has been parsed, then kernel initialization can proceed in the normal +way. At some point in this process, unflatten_device_tree() is called +to convert the data into a more efficient runtime representation. +This is also when machine-specific setup hooks will get called, like +the machine_desc .init_early(), .init_irq() and .init_machine() hooks +on ARM. The remainder of this section uses examples from the ARM +implementation, but all architectures will do pretty much the same +thing when using a DT. + +As can be guessed by the names, .init_early() is used for any machine- +specific setup that needs to be executed early in the boot process, +and .init_irq() is used to set up interrupt handling. Using a DT +doesn't materially change the behaviour of either of these functions. +If a DT is provided, then both .init_early() and .init_irq() are able +to call any of the DT query functions (of_* in include/linux/of*.h) to +get additional data about the platform. + +The most interesting hook in the DT context is .init_machine() which +is primarily responsible for populating the Linux device model with +data about the platform. Historically this has been implemented on +embedded platforms by defining a set of static clock structures, +platform_devices, and other data in the board support .c file, and +registering it en-masse in .init_machine(). When DT is used, then +instead of hard coding static devices for each platform, the list of +devices can be obtained by parsing the DT, and allocating device +structures dynamically. + +The simplest case is when .init_machine() is only responsible for +registering a block of platform_devices. A platform_device is a concept +used by Linux for memory or I/O mapped devices which cannot be detected +by hardware, and for 'composite' or 'virtual' devices (more on those +later). While there is no 'platform device' terminology for the DT, +platform devices roughly correspond to device nodes at the root of the +tree and children of simple memory mapped bus nodes. + +About now is a good time to lay out an example. Here is part of the +device tree for the NVIDIA Tegra board. + +/{ + compatible = "nvidia,harmony", "nvidia,tegra20"; + #address-cells = <1>; + #size-cells = <1>; + interrupt-parent = <&intc>; + + chosen { }; + aliases { }; + + memory { + device_type = "memory"; + reg = <0x00000000 0x40000000>; + }; + + soc { + compatible = "nvidia,tegra20-soc", "simple-bus"; + #address-cells = <1>; + #size-cells = <1>; + ranges; + + intc: interrupt-controller@50041000 { + compatible = "nvidia,tegra20-gic"; + interrupt-controller; + #interrupt-cells = <1>; + reg = <0x50041000 0x1000>, < 0x50040100 0x0100 >; + }; + + serial@70006300 { + compatible = "nvidia,tegra20-uart"; + reg = <0x70006300 0x100>; + interrupts = <122>; + }; + + i2s-1: i2s@70002800 { + compatible = "nvidia,tegra20-i2s"; + reg = <0x70002800 0x100>; + interrupts = <77>; + codec = <&wm8903>; + }; + + i2c@7000c000 { + compatible = "nvidia,tegra20-i2c"; + #address-cells = <1>; + #size-cells = <1>; + reg = <0x7000c000 0x100>; + interrupts = <70>; + + wm8903: codec@1a { + compatible = "wlf,wm8903"; + reg = <0x1a>; + interrupts = <347>; + }; + }; + }; + + sound { + compatible = "nvidia,harmony-sound"; + i2s-controller = <&i2s-1>; + i2s-codec = <&wm8903>; + }; +}; + +At .machine_init() time, Tegra board support code will need to look at +this DT and decide which nodes to create platform_devices for. +However, looking at the tree, it is not immediately obvious what kind +of device each node represents, or even if a node represents a device +at all. The /chosen, /aliases, and /memory nodes are informational +nodes that don't describe devices (although arguably memory could be +considered a device). The children of the /soc node are memory mapped +devices, but the codec@1a is an i2c device, and the sound node +represents not a device, but rather how other devices are connected +together to create the audio subsystem. I know what each device is +because I'm familiar with the board design, but how does the kernel +know what to do with each node? + +The trick is that the kernel starts at the root of the tree and looks +for nodes that have a 'compatible' property. First, it is generally +assumed that any node with a 'compatible' property represents a device +of some kind, and second, it can be assumed that any node at the root +of the tree is either directly attached to the processor bus, or is a +miscellaneous system device that cannot be described any other way. +For each of these nodes, Linux allocates and registers a +platform_device, which in turn may get bound to a platform_driver. + +Why is using a platform_device for these nodes a safe assumption? +Well, for the way that Linux models devices, just about all bus_types +assume that its devices are children of a bus controller. For +example, each i2c_client is a child of an i2c_master. Each spi_device +is a child of an SPI bus. Similarly for USB, PCI, MDIO, etc. The +same hierarchy is also found in the DT, where I2C device nodes only +ever appear as children of an I2C bus node. Ditto for SPI, MDIO, USB, +etc. The only devices which do not require a specific type of parent +device are platform_devices (and amba_devices, but more on that +later), which will happily live at the base of the Linux /sys/devices +tree. Therefore, if a DT node is at the root of the tree, then it +really probably is best registered as a platform_device. + +Linux board support code calls of_platform_populate(NULL, NULL, NULL) +to kick off discovery of devices at the root of the tree. The +parameters are all NULL because when starting from the root of the +tree, there is no need to provide a starting node (the first NULL), a +parent struct device (the last NULL), and we're not using a match +table (yet). For a board that only needs to register devices, +.init_machine() can be completely empty except for the +of_platform_populate() call. + +In the Tegra example, this accounts for the /soc and /sound nodes, but +what about the children of the SoC node? Shouldn't they be registered +as platform devices too? For Linux DT support, the generic behaviour +is for child devices to be registered by the parent's device driver at +driver .probe() time. So, an i2c bus device driver will register a +i2c_client for each child node, an SPI bus driver will register +its spi_device children, and similarly for other bus_types. +According to that model, a driver could be written that binds to the +SoC node and simply registers platform_devices for each of its +children. The board support code would allocate and register an SoC +device, an SoC device driver would bind to the SoC device, and +register platform_devices for /soc/interrupt-controller, /soc/serial, +/soc/i2s, and /soc/i2c in its .probe() hook. Easy, right? Although +it is a lot of mucking about for just registering platform devices. + +It turns out that registering children of certain platform_devices as +more platform_devices is a common pattern, and the device tree support +code reflects that. The second argument to of_platform_populate() is +an of_device_id table, and any node that matches an entry in that +table will also get its child nodes registered. In the tegra case, +the code can look something like this: + +static struct of_device_id harmony_bus_ids[] __initdata = { + { .compatible = "simple-bus", }, + {} +}; + +static void __init harmony_init_machine(void) +{ + /* ... */ + of_platform_populate(NULL, harmony_bus_ids, NULL); +} + +"simple-bus" is defined in the ePAPR 1.0 specification as a property +meaning a simple memory mapped bus, so the of_platform_populate() code +could be written to just assume simple-bus compatible nodes will +always be traversed. However, we pass it in as an argument so that +board support code can always override the default behaviour. + +<h2>Appendix A: AMBA devices</h2> + +ARM Primecells are a certain kind of device attached to the ARM AMBA +bus which include some support for hardware detection and power +management. In Linux, struct amba_device and the amba_bus_type is +used to represent Primecell devices. However, the fiddly bit is that +not all devices on an AMBA bus are Primecells, and for Linux it is +typical for both amba_device and platform_device instances to be +siblings of the same bus segment. + +When using the DT, this creates problems for of_platform_populate() +because it must decide whether to register each node as either a +platform_device or an amba_device. This unfortunately complicates the +device creation model a little bit, but the solution turns out not to +be too invasive. If a node is compatible with "arm,amba-primecell", then +of_platform_populate() will register it as an amba_device instead of a +platform_device. diff --git a/Documentation/hwmon/exynos4_tmu b/Documentation/hwmon/exynos4_tmu new file mode 100644 index 00000000000..c3c6b41db60 --- /dev/null +++ b/Documentation/hwmon/exynos4_tmu @@ -0,0 +1,81 @@ +Kernel driver exynos4_tmu +================= + +Supported chips: +* ARM SAMSUNG EXYNOS4 series of SoC + Prefix: 'exynos4-tmu' + Datasheet: Not publicly available + +Authors: Donggeun Kim <dg77.kim@samsung.com> + +Description +----------- + +This driver allows to read temperature inside SAMSUNG EXYNOS4 series of SoC. + +The chip only exposes the measured 8-bit temperature code value +through a register. +Temperature can be taken from the temperature code. +There are three equations converting from temperature to temperature code. + +The three equations are: + 1. Two point trimming + Tc = (T - 25) * (TI2 - TI1) / (85 - 25) + TI1 + + 2. One point trimming + Tc = T + TI1 - 25 + + 3. No trimming + Tc = T + 50 + + Tc: Temperature code, T: Temperature, + TI1: Trimming info for 25 degree Celsius (stored at TRIMINFO register) + Temperature code measured at 25 degree Celsius which is unchanged + TI2: Trimming info for 85 degree Celsius (stored at TRIMINFO register) + Temperature code measured at 85 degree Celsius which is unchanged + +TMU(Thermal Management Unit) in EXYNOS4 generates interrupt +when temperature exceeds pre-defined levels. +The maximum number of configurable threshold is four. +The threshold levels are defined as follows: + Level_0: current temperature > trigger_level_0 + threshold + Level_1: current temperature > trigger_level_1 + threshold + Level_2: current temperature > trigger_level_2 + threshold + Level_3: current temperature > trigger_level_3 + threshold + + The threshold and each trigger_level are set + through the corresponding registers. + +When an interrupt occurs, this driver notify user space of +one of four threshold levels for the interrupt +through kobject_uevent_env and sysfs_notify functions. +Although an interrupt condition for level_0 can be set, +it is not notified to user space through sysfs_notify function. + +Sysfs Interface +--------------- +name name of the temperature sensor + RO + +temp1_input temperature + RO + +temp1_max temperature for level_1 interrupt + RO + +temp1_crit temperature for level_2 interrupt + RO + +temp1_emergency temperature for level_3 interrupt + RO + +temp1_max_alarm alarm for level_1 interrupt + RO + +temp1_crit_alarm + alarm for level_2 interrupt + RO + +temp1_emergency_alarm + alarm for level_3 interrupt + RO diff --git a/Documentation/hwspinlock.txt b/Documentation/hwspinlock.txt index 7dcd1a4e726..69966813d59 100644 --- a/Documentation/hwspinlock.txt +++ b/Documentation/hwspinlock.txt @@ -39,23 +39,20 @@ independent, drivers. in case an unused hwspinlock isn't available. Users of this API will usually want to communicate the lock's id to the remote core before it can be used to achieve synchronization. - Can be called from an atomic context (this function will not sleep) but - not from within interrupt context. + Should be called from a process context (might sleep). struct hwspinlock *hwspin_lock_request_specific(unsigned int id); - assign a specific hwspinlock id and return its address, or NULL if that hwspinlock is already in use. Usually board code will be calling this function in order to reserve specific hwspinlock ids for predefined purposes. - Can be called from an atomic context (this function will not sleep) but - not from within interrupt context. + Should be called from a process context (might sleep). int hwspin_lock_free(struct hwspinlock *hwlock); - free a previously-assigned hwspinlock; returns 0 on success, or an appropriate error code on failure (e.g. -EINVAL if the hwspinlock is already free). - Can be called from an atomic context (this function will not sleep) but - not from within interrupt context. + Should be called from a process context (might sleep). int hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int timeout); - lock a previously-assigned hwspinlock with a timeout limit (specified in @@ -232,15 +229,14 @@ int hwspinlock_example2(void) int hwspin_lock_register(struct hwspinlock *hwlock); - to be called from the underlying platform-specific implementation, in - order to register a new hwspinlock instance. Can be called from an atomic - context (this function will not sleep) but not from within interrupt - context. Returns 0 on success, or appropriate error code on failure. + order to register a new hwspinlock instance. Should be called from + a process context (this function might sleep). + Returns 0 on success, or appropriate error code on failure. struct hwspinlock *hwspin_lock_unregister(unsigned int id); - to be called from the underlying vendor-specific implementation, in order to unregister an existing (and unused) hwspinlock instance. - Can be called from an atomic context (will not sleep) but not from - within interrupt context. + Should be called from a process context (this function might sleep). Returns the address of hwspinlock on success, or NULL on error (e.g. if the hwspinlock is sill in use). diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 6066e3a6b9a..d3710dc6d25 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -782,6 +782,16 @@ will behave normally, not taking the autosuspend delay into account. Similarly, if the power.use_autosuspend field isn't set then the autosuspend helper functions will behave just like the non-autosuspend counterparts. +Under some circumstances a driver or subsystem may want to prevent a device +from autosuspending immediately, even though the usage counter is zero and the +autosuspend delay time has expired. If the ->runtime_suspend() callback +returns -EAGAIN or -EBUSY, and if the next autosuspend delay expiration time is +in the future (as it normally would be if the callback invoked +pm_runtime_mark_last_busy()), the PM core will automatically reschedule the +autosuspend. The ->runtime_suspend() callback can't do this rescheduling +itself because no suspend requests of any kind are accepted while the device is +suspending (i.e., while the callback is running). + The implementation is well suited for asynchronous use in interrupt contexts. However such use inevitably involves races, because the PM core can't synchronize ->runtime_suspend() callbacks with the arrival of I/O requests. diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index d70c93bdcad..f8961402a85 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -408,6 +408,7 @@ STAC92HD83* ref Reference board mic-ref Reference board with power management for ports dell-s14 Dell laptop + dell-vostro-3500 Dell Vostro 3500 laptop hp HP laptops with (inverted) mute-LED hp-dv7-4000 HP dv-7 4000 auto BIOS setup (default) diff --git a/Documentation/stable_kernel_rules.txt b/Documentation/stable_kernel_rules.txt index e213f45cf9d..21fd05c28e7 100644 --- a/Documentation/stable_kernel_rules.txt +++ b/Documentation/stable_kernel_rules.txt @@ -24,10 +24,10 @@ Rules on what kind of patches are accepted, and which ones are not, into the Procedure for submitting patches to the -stable tree: - Send the patch, after verifying that it follows the above rules, to - stable@kernel.org. You must note the upstream commit ID in the changelog - of your submission. + stable@vger.kernel.org. You must note the upstream commit ID in the + changelog of your submission. - To have the patch automatically included in the stable tree, add the tag - Cc: stable@kernel.org + Cc: stable@vger.kernel.org in the sign-off area. Once the patch is merged it will be applied to the stable tree without anything else needing to be done by the author or subsystem maintainer. @@ -35,10 +35,10 @@ Procedure for submitting patches to the -stable tree: cherry-picked than this can be specified in the following format in the sign-off area: - Cc: <stable@kernel.org> # .32.x: a1f84a3: sched: Check for idle - Cc: <stable@kernel.org> # .32.x: 1b9508f: sched: Rate-limit newidle - Cc: <stable@kernel.org> # .32.x: fd21073: sched: Fix affinity logic - Cc: <stable@kernel.org> # .32.x + Cc: <stable@vger.kernel.org> # .32.x: a1f84a3: sched: Check for idle + Cc: <stable@vger.kernel.org> # .32.x: 1b9508f: sched: Rate-limit newidle + Cc: <stable@vger.kernel.org> # .32.x: fd21073: sched: Fix affinity logic + Cc: <stable@vger.kernel.org> # .32.x Signed-off-by: Ingo Molnar <mingo@elte.hu> The tag sequence has the meaning of: diff --git a/Documentation/thermal/cpu-cooling-api.txt b/Documentation/thermal/cpu-cooling-api.txt new file mode 100644 index 00000000000..d30b4f276a9 --- /dev/null +++ b/Documentation/thermal/cpu-cooling-api.txt @@ -0,0 +1,52 @@ +CPU cooling api's How To +=================================== + +Written by Amit Daniel Kachhap <amit.kachhap@linaro.org> + +Updated: 13 Dec 2011 + +Copyright (c) 2011 Samsung Electronics Co., Ltd(http://www.samsung.com) + +0. Introduction + +The generic cpu cooling(freq clipping, cpuhotplug) provides +registration/unregistration api's to the user. The binding of the cooling +devices to the trip types is left for the user. The registration api's returns +the cooling device pointer. + +1. cpufreq cooling api's + +1.1 cpufreq registration api's +1.1.1 struct thermal_cooling_device *cpufreq_cooling_register( + struct freq_pctg_table *tab_ptr, unsigned int tab_size, + const struct cpumask *mask_val) + + This interface function registers the cpufreq cooling device with the name + "thermal-cpufreq". + + tab_ptr: The table containing the percentage of frequency to be clipped for + each cooling state. + .freq_clip_pctg[NR_CPUS]:Percentage of frequency to be clipped for each + cpu. + .polling_interval: polling interval for this cooling state. + tab_size: the total number of cooling state. + mask_val: all the allowed cpu's where frequency clipping can happen. + +1.1.2 void cpufreq_cooling_unregister(void) + + This interface function unregisters the "thermal-cpufreq" cooling device. + + +1.2 cpuhotplug registration api's + +1.2.1 struct thermal_cooling_device *cpuhotplug_cooling_register( + const struct cpumask *mask_val) + + This interface function registers the cpuhotplug cooling device with the name + "thermal-cpuhotplug". + + mask_val: all the allowed cpu's which can be hotplugged out. + +1.1.2 void cpuhotplug_cooling_unregister(void) + + This interface function unregisters the "thermal-cpuhotplug" cooling device. diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index b61e46f449a..5c1d44e0df5 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -184,8 +184,8 @@ trip_point_[0-*]_temp trip_point_[0-*]_type Strings which indicate the type of the trip point. - E.g. it can be one of critical, hot, passive, active[0-*] for ACPI - thermal zone. + E.g. it can be one of critical, hot, passive, active[0-1], + state-active[0-*] for ACPI thermal zone. RO, Optional cdev[0-*] |