diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-07 21:55:37 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-07 21:55:37 -0700 |
commit | 82efe439599439a5e1e225ce5740e6cfb777a7dd (patch) | |
tree | ef8b08a66b2c1f538519fd40a7538ca8aa6e12ef /Documentation | |
parent | dd5001e21a991b731d659857cd07acc7a13e6789 (diff) | |
parent | 2a656cb5a4a3473c5fc6bf4fddc3560ceed53220 (diff) |
Merge tag 'devicetree-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree updates from Rob Herring:
- Fix possible memory leak in reserved-memory failure case
- Support for DMA parent bus which are not a parent node
- Clang -Wunsequenced fix
- Remove some unnecessary prints on memory alloc failures
- Various printk msg and comment fixes
- Update DT schema tools repository location
- Convert simple-framebuffer binding to DT schema
- Bindings for isl68137 and ir38064 trivial devices
- New documentation on binding do's and don't's for binding writers to
ignore
* tag 'devicetree-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (22 commits)
of: unittest: Remove error printing on OOM
of: irq: Remove WARN_ON() for kzalloc() failure
dt-bindings: pinctrl: fix bias-pull,up typo
dt-bindings: Update schema project location to devicetree.org github group
of: fix clang -Wunsequenced for be32_to_cpu()
of/device.c: fix the wrong comments
dt-bindings: Add isl68137 as a trivial device
dt-bindings: Add ir38064 as a trivial device
of: del redundant type conversion
dt-bindings: mfd: axp20x: Add fallback for axp805
of: Improve of_phandle_iterator_next() error message
dt-bindings: connector: Spelling mistake
dt-bindings: Add schemas for simple-framebuffer
of: address: Add support for the parent DMA bus
of: address: Retrieve a parent through a callback in __of_translate_address
dt-bindings: bus: Add binding for the Allwinner MBUS controller
dt-bindings: interconnect: Add a dma interconnect name
of: use correct function prototype for of_overlay_fdt_apply()
of: reserved_mem: fix reserve memory leak
of: property: Document that of_graph_get_endpoint_by_regs needs of_node_put
...
Diffstat (limited to 'Documentation')
19 files changed, 275 insertions, 167 deletions
diff --git a/Documentation/devicetree/bindings/arm/cpus.yaml b/Documentation/devicetree/bindings/arm/cpus.yaml index 82dd7582e945..591bbd012d63 100644 --- a/Documentation/devicetree/bindings/arm/cpus.yaml +++ b/Documentation/devicetree/bindings/arm/cpus.yaml @@ -67,6 +67,7 @@ properties: patternProperties: '^cpu@[0-9a-f]+$': + type: object properties: device_type: const: cpu diff --git a/Documentation/devicetree/bindings/arm/sunxi/sunxi-mbus.txt b/Documentation/devicetree/bindings/arm/sunxi/sunxi-mbus.txt new file mode 100644 index 000000000000..1464a4713553 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/sunxi/sunxi-mbus.txt @@ -0,0 +1,36 @@ +Allwinner Memory Bus (MBUS) controller + +The MBUS controller drives the MBUS that other devices in the SoC will +use to perform DMA. It also has a register interface that allows to +monitor and control the bandwidth and priorities for masters on that +bus. + +Required properties: + - compatible: Must be one of: + - allwinner,sun5i-a13-mbus + - reg: Offset and length of the register set for the controller + - clocks: phandle to the clock driving the controller + - dma-ranges: See section 2.3.9 of the DeviceTree Specification + - #interconnect-cells: Must be one, with the argument being the MBUS + port ID + +Each device having to perform their DMA through the MBUS must have the +interconnects and interconnect-names properties set to the MBUS +controller and with "dma-mem" as the interconnect name. + +Example: + +mbus: dram-controller@1c01000 { + compatible = "allwinner,sun5i-a13-mbus"; + reg = <0x01c01000 0x1000>; + clocks = <&ccu CLK_MBUS>; + dma-ranges = <0x00000000 0x40000000 0x20000000>; + #interconnect-cells = <1>; +}; + +fe0: display-frontend@1e00000 { + compatible = "allwinner,sun5i-a13-display-frontend"; + ... + interconnects = <&mbus 19>; + interconnect-names = "dma-mem"; +}; diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt index a9a2f2fc44f2..cef556d4e5ee 100644 --- a/Documentation/devicetree/bindings/connector/usb-connector.txt +++ b/Documentation/devicetree/bindings/connector/usb-connector.txt @@ -47,7 +47,7 @@ Required properties for usb-c-connector with power delivery support: Required nodes: - any data bus to the connector should be modeled using the OF graph bindings specified in bindings/graph.txt, unless the bus is between parent node and - the connector. Since single connector can have multpile data buses every bus + the connector. Since single connector can have multiple data buses every bus has assigned OF graph port number as follows: 0: High Speed (HS), present in all connectors, 1: Super Speed (SS), present in SS capable connectors, diff --git a/Documentation/devicetree/bindings/display/amlogic,simple-framebuffer.txt b/Documentation/devicetree/bindings/display/amlogic,simple-framebuffer.txt deleted file mode 100644 index aaa6c24c8e70..000000000000 --- a/Documentation/devicetree/bindings/display/amlogic,simple-framebuffer.txt +++ /dev/null @@ -1,33 +0,0 @@ -Meson specific Simple Framebuffer bindings - -This binding documents meson specific extensions to the simple-framebuffer -bindings. The meson simplefb u-boot code relies on the devicetree containing -pre-populated simplefb nodes. - -These extensions are intended so that u-boot can select the right node based -on which pipeline is being used. As such they are solely intended for -firmware / bootloader use, and the OS should ignore them. - -Required properties: -- compatible: "amlogic,simple-framebuffer", "simple-framebuffer" -- amlogic,pipeline, one of: - "vpu-cvbs" - "vpu-hdmi" - -Example: - -chosen { - #address-cells = <2>; - #size-cells = <2>; - ranges; - - simplefb_hdmi: framebuffer-hdmi { - compatible = "amlogic,simple-framebuffer", - "simple-framebuffer"; - amlogic,pipeline = "vpu-hdmi"; - clocks = <&clkc CLKID_HDMI_PCLK>, - <&clkc CLKID_CLK81>, - <&clkc CLKID_GCLK_VENCI_INT0>; - power-domains = <&pwrc_vpu>; - }; -}; diff --git a/Documentation/devicetree/bindings/display/simple-framebuffer-sunxi.txt b/Documentation/devicetree/bindings/display/simple-framebuffer-sunxi.txt deleted file mode 100644 index d693b8dc9a62..000000000000 --- a/Documentation/devicetree/bindings/display/simple-framebuffer-sunxi.txt +++ /dev/null @@ -1,36 +0,0 @@ -Sunxi specific Simple Framebuffer bindings - -This binding documents sunxi specific extensions to the simple-framebuffer -bindings. The sunxi simplefb u-boot code relies on the devicetree containing -pre-populated simplefb nodes. - -These extensions are intended so that u-boot can select the right node based -on which pipeline is being used. As such they are solely intended for -firmware / bootloader use, and the OS should ignore them. - -Required properties: -- compatible: "allwinner,simple-framebuffer" -- allwinner,pipeline, one of: - "de_be0-lcd0" - "de_be1-lcd1" - "de_be0-lcd0-hdmi" - "de_be1-lcd1-hdmi" - "mixer0-lcd0" - "mixer0-lcd0-hdmi" - "mixer1-lcd1-hdmi" - "mixer1-lcd1-tve" - -Example: - -chosen { - #address-cells = <1>; - #size-cells = <1>; - ranges; - - framebuffer@0 { - compatible = "allwinner,simple-framebuffer", "simple-framebuffer"; - allwinner,pipeline = "de_be0-lcd0-hdmi"; - clocks = <&pll5 1>, <&ahb_gates 36>, <&ahb_gates 43>, - <&ahb_gates 44>; - }; -}; diff --git a/Documentation/devicetree/bindings/display/simple-framebuffer.txt b/Documentation/devicetree/bindings/display/simple-framebuffer.txt deleted file mode 100644 index 5a9ce511be88..000000000000 --- a/Documentation/devicetree/bindings/display/simple-framebuffer.txt +++ /dev/null @@ -1,91 +0,0 @@ -Simple Framebuffer - -A simple frame-buffer describes a frame-buffer setup by firmware or -the bootloader, with the assumption that the display hardware has already -been set up to scan out from the memory pointed to by the reg property. - -Since simplefb nodes represent runtime information they must be sub-nodes of -the chosen node (*). Simplefb nodes must be named "framebuffer@<address>". - -If the devicetree contains nodes for the display hardware used by a simplefb, -then the simplefb node must contain a property called "display", which -contains a phandle pointing to the primary display hw node, so that the OS -knows which simplefb to disable when handing over control to a driver for the -real hardware. The bindings for the hw nodes must specify which node is -considered the primary node. - -It is advised to add display# aliases to help the OS determine how to number -things. If display# aliases are used, then if the simplefb node contains a -"display" property then the /aliases/display# path must point to the display -hw node the "display" property points to, otherwise it must point directly -to the simplefb node. - -If a simplefb node represents the preferred console for user interaction, -then the chosen node's stdout-path property should point to it, or to the -primary display hw node, as with display# aliases. If display aliases are -used then it should be set to the alias instead. - -It is advised that devicetree files contain pre-filled, disabled framebuffer -nodes, so that the firmware only needs to update the mode information and -enable them. This way if e.g. later on support for more display clocks get -added, the simplefb nodes will already contain this info and the firmware -does not need to be updated. - -If pre-filled framebuffer nodes are used, the firmware may need extra -information to find the right node. In that case an extra platform specific -compatible and platform specific properties should be used and documented, -see e.g. simple-framebuffer-sunxi.txt . - -Required properties: -- compatible: "simple-framebuffer" -- reg: Should contain the location and size of the framebuffer memory. -- width: The width of the framebuffer in pixels. -- height: The height of the framebuffer in pixels. -- stride: The number of bytes in each line of the framebuffer. -- format: The format of the framebuffer surface. Valid values are: - - r5g6b5 (16-bit pixels, d[15:11]=r, d[10:5]=g, d[4:0]=b). - - a8b8g8r8 (32-bit pixels, d[31:24]=a, d[23:16]=b, d[15:8]=g, d[7:0]=r). - -Optional properties: -- clocks : List of clocks used by the framebuffer. -- *-supply : Any number of regulators used by the framebuffer. These should - be named according to the names in the device's design. - - The above resources are expected to already be configured correctly. - The OS must ensure they are not modified or disabled while the simple - framebuffer remains active. - -- display : phandle pointing to the primary display hardware node - -Example: - -aliases { - display0 = &lcdc0; -} - -chosen { - framebuffer0: framebuffer@1d385000 { - compatible = "simple-framebuffer"; - reg = <0x1d385000 (1600 * 1200 * 2)>; - width = <1600>; - height = <1200>; - stride = <(1600 * 2)>; - format = "r5g6b5"; - clocks = <&ahb_gates 36>, <&ahb_gates 43>, <&ahb_gates 44>; - lcd-supply = <®_dc1sw>; - display = <&lcdc0>; - }; - stdout-path = "display0"; -}; - -soc@1c00000 { - lcdc0: lcdc@1c0c000 { - compatible = "allwinner,sun4i-a10-lcdc"; - ... - }; -}; - - -*) Older devicetree files may have a compatible = "simple-framebuffer" node -in a different place, operating systems must first enumerate any compatible -nodes found under chosen and then check for other compatible nodes. diff --git a/Documentation/devicetree/bindings/display/simple-framebuffer.yaml b/Documentation/devicetree/bindings/display/simple-framebuffer.yaml new file mode 100644 index 000000000000..b052d76cf8b6 --- /dev/null +++ b/Documentation/devicetree/bindings/display/simple-framebuffer.yaml @@ -0,0 +1,160 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/display/simple-framebuffer.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Simple Framebuffer Device Tree Bindings + +maintainers: + - Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> + - Hans de Goede <hdegoede@redhat.com> + +description: |+ + A simple frame-buffer describes a frame-buffer setup by firmware or + the bootloader, with the assumption that the display hardware has + already been set up to scan out from the memory pointed to by the + reg property. + + Since simplefb nodes represent runtime information they must be + sub-nodes of the chosen node (*). Simplefb nodes must be named + framebuffer@<address>. + + If the devicetree contains nodes for the display hardware used by a + simplefb, then the simplefb node must contain a property called + display, which contains a phandle pointing to the primary display + hw node, so that the OS knows which simplefb to disable when handing + over control to a driver for the real hardware. The bindings for the + hw nodes must specify which node is considered the primary node. + + It is advised to add display# aliases to help the OS determine how + to number things. If display# aliases are used, then if the simplefb + node contains a display property then the /aliases/display# path + must point to the display hw node the display property points to, + otherwise it must point directly to the simplefb node. + + If a simplefb node represents the preferred console for user + interaction, then the chosen node stdout-path property should point + to it, or to the primary display hw node, as with display# + aliases. If display aliases are used then it should be set to the + alias instead. + + It is advised that devicetree files contain pre-filled, disabled + framebuffer nodes, so that the firmware only needs to update the + mode information and enable them. This way if e.g. later on support + for more display clocks get added, the simplefb nodes will already + contain this info and the firmware does not need to be updated. + + If pre-filled framebuffer nodes are used, the firmware may need + extra information to find the right node. In that case an extra + platform specific compatible and platform specific properties should + be used and documented. + +properties: + compatible: + items: + - enum: + - allwinner,simple-framebuffer + - amlogic,simple-framebuffer + - const: simple-framebuffer + + reg: + description: Location and size of the framebuffer memory + + clocks: + description: List of clocks used by the framebuffer. + + power-domains: + description: List of power domains used by the framebuffer. + + width: + $ref: /schemas/types.yaml#/definitions/uint32 + description: Width of the framebuffer in pixels + + height: + $ref: /schemas/types.yaml#/definitions/uint32 + description: Height of the framebuffer in pixels + + stride: + $ref: /schemas/types.yaml#/definitions/uint32 + description: Number of bytes of a line in the framebuffer + + format: + description: > + Format of the framebuffer: + * `a8b8g8r8` - 32-bit pixels, d[31:24]=a, d[23:16]=b, d[15:8]=g, d[7:0]=r + * `r5g6b5` - 16-bit pixels, d[15:11]=r, d[10:5]=g, d[4:0]=b + enum: + - a8b8g8r8 + - r5g6b5 + + display: + $ref: /schemas/types.yaml#/definitions/phandle + description: Primary display hardware node + + allwinner,pipeline: + description: Pipeline used by the framebuffer on Allwinner SoCs + enum: + - de_be0-lcd0 + - de_be0-lcd0-hdmi + - de_be0-lcd0-tve0 + - de_be1-lcd0 + - de_be1-lcd1-hdmi + - de_fe0-de_be0-lcd0 + - de_fe0-de_be0-lcd0-hdmi + - de_fe0-de_be0-lcd0-tve0 + - mixer0-lcd0 + - mixer0-lcd0-hdmi + - mixer1-lcd1-hdmi + - mixer1-lcd1-tve + + amlogic,pipeline: + description: Pipeline used by the framebuffer on Amlogic SoCs + enum: + - vpu-cvbs + - vpu-hdmi + +patternProperties: + "^[a-zA-Z0-9-]+-supply$": + $ref: /schemas/types.yaml#/definitions/phandle + description: + Regulators used by the framebuffer. These should be named + according to the names in the device design. + +required: + # The binding requires also reg, width, height, stride and format, + # but usually they will be filled by the bootloader. + - compatible + +additionalProperties: false + +examples: + - | + aliases { + display0 = &lcdc0; + }; + + chosen { + #address-cells = <1>; + #size-cells = <1>; + stdout-path = "display0"; + framebuffer0: framebuffer@1d385000 { + compatible = "simple-framebuffer"; + reg = <0x1d385000 3840000>; + width = <1600>; + height = <1200>; + stride = <3200>; + format = "r5g6b5"; + clocks = <&ahb_gates 36>, <&ahb_gates 43>, <&ahb_gates 44>; + lcd-supply = <®_dc1sw>; + display = <&lcdc0>; + }; + }; + + soc@1c00000 { + lcdc0: lcdc@1c0c000 { + compatible = "allwinner,sun4i-a10-lcdc"; + }; + }; + +... diff --git a/Documentation/devicetree/bindings/interconnect/interconnect.txt b/Documentation/devicetree/bindings/interconnect/interconnect.txt index 5a3c575b387a..6f5d23a605b7 100644 --- a/Documentation/devicetree/bindings/interconnect/interconnect.txt +++ b/Documentation/devicetree/bindings/interconnect/interconnect.txt @@ -51,6 +51,10 @@ interconnect-names : List of interconnect path name strings sorted in the same interconnect-names to match interconnect paths with interconnect specifier pairs. + Reserved interconnect names: + * dma-mem: Path from the device to the main memory of + the system + Example: sdhci@7864000 { diff --git a/Documentation/devicetree/bindings/interrupt-controller/arm,gic.yaml b/Documentation/devicetree/bindings/interrupt-controller/arm,gic.yaml index 758fbd7128e7..54838d4ea44c 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/arm,gic.yaml +++ b/Documentation/devicetree/bindings/interrupt-controller/arm,gic.yaml @@ -129,6 +129,7 @@ required: patternProperties: "^v2m@[0-9a-f]+$": + type: object description: | * GICv2m extension for MSI/MSI-x support (Optional) diff --git a/Documentation/devicetree/bindings/mfd/axp20x.txt b/Documentation/devicetree/bindings/mfd/axp20x.txt index 2af4ff95d6bc..4991a6415796 100644 --- a/Documentation/devicetree/bindings/mfd/axp20x.txt +++ b/Documentation/devicetree/bindings/mfd/axp20x.txt @@ -25,6 +25,7 @@ Required properties: * "x-powers,axp223" * "x-powers,axp803" * "x-powers,axp806" + * "x-powers,axp805", "x-powers,axp806" * "x-powers,axp809" * "x-powers,axp813" - reg: The I2C slave address or RSB hardware address for the AXP chip diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,apq8064-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,apq8064-pinctrl.txt index c2dbb3e8d840..4e90ddd77784 100644 --- a/Documentation/devicetree/bindings/pinctrl/qcom,apq8064-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/qcom,apq8064-pinctrl.txt @@ -42,7 +42,7 @@ information about e.g. the mux function. The following generic properties as defined in pinctrl-bindings.txt are valid to specify in a pin configuration subnode: - pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength, + pins, function, bias-disable, bias-pull-down, bias-pull-up, drive-strength, output-low, output-high. Non-empty subnodes must specify the 'pins' property. diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt index 991be0cd0948..84be0f2c6f3b 100644 --- a/Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt @@ -44,7 +44,7 @@ information about e.g. the mux function. The following generic properties as defined in pinctrl-bindings.txt are valid to specify in a pin configuration subnode: - pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength. + pins, function, bias-disable, bias-pull-down, bias-pull-up, drive-strength. Non-empty subnodes must specify the 'pins' property. Note that not all properties are valid for all pins. diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,ipq8064-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,ipq8064-pinctrl.txt index 7ed56a1b70fc..a7aaaa7db83b 100644 --- a/Documentation/devicetree/bindings/pinctrl/qcom,ipq8064-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/qcom,ipq8064-pinctrl.txt @@ -42,7 +42,7 @@ information about e.g. the mux function. The following generic properties as defined in pinctrl-bindings.txt are valid to specify in a pin configuration subnode: - pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength, + pins, function, bias-disable, bias-pull-down, bias-pull-up, drive-strength, output-low, output-high. Non-empty subnodes must specify the 'pins' property. diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,msm8660-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,msm8660-pinctrl.txt index cdc4787e59d2..f095209848c8 100644 --- a/Documentation/devicetree/bindings/pinctrl/qcom,msm8660-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/qcom,msm8660-pinctrl.txt @@ -42,7 +42,7 @@ information about e.g. the mux function. The following generic properties as defined in pinctrl-bindings.txt are valid to specify in a pin configuration subnode: - pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength, + pins, function, bias-disable, bias-pull-down, bias-pull-up, drive-strength, output-low, output-high. Non-empty subnodes must specify the 'pins' property. diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt index c22e6c425d0b..004056506679 100644 --- a/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt @@ -41,7 +41,7 @@ information about e.g. the mux function. The following generic properties as defined in pinctrl-bindings.txt are valid to specify in a pin configuration subnode: - pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength. + pins, function, bias-disable, bias-pull-down, bias-pull-up, drive-strength. Non-empty subnodes must specify the 'pins' property. Note that not all properties are valid for all pins. diff --git a/Documentation/devicetree/bindings/timer/arm,arch_timer_mmio.yaml b/Documentation/devicetree/bindings/timer/arm,arch_timer_mmio.yaml index c4ab59550fc2..b3f0fe96ff0d 100644 --- a/Documentation/devicetree/bindings/timer/arm,arch_timer_mmio.yaml +++ b/Documentation/devicetree/bindings/timer/arm,arch_timer_mmio.yaml @@ -59,6 +59,7 @@ properties: patternProperties: '^frame@[0-9a-z]*$': + type: object description: A timer node has up to 8 frame sub-nodes, each with the following properties. properties: frame-number: diff --git a/Documentation/devicetree/bindings/trivial-devices.yaml b/Documentation/devicetree/bindings/trivial-devices.yaml index d79fb22bde39..747fd3f689dc 100644 --- a/Documentation/devicetree/bindings/trivial-devices.yaml +++ b/Documentation/devicetree/bindings/trivial-devices.yaml @@ -92,6 +92,8 @@ properties: - fsl,sgtl5000 # G751: Digital Temperature Sensor and Thermal Watchdog with Two-Wire Interface - gmt,g751 + # Infineon IR38064 Voltage Regulator + - infineon,ir38064 # Infineon SLB9635 (Soft-) I2C TPM (old protocol, max 100khz) - infineon,slb9635tt # Infineon SLB9645 I2C TPM (new protocol, max 400khz) @@ -102,6 +104,8 @@ properties: - isil,isl29028 # Intersil ISL29030 Ambient Light and Proximity Sensor - isil,isl29030 + # Intersil ISL68137 Digital Output Configurable PWM Controller + - isil,isl68137 # 5 Bit Programmable, Pulse-Width Modulator - maxim,ds1050 # Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs diff --git a/Documentation/devicetree/bindings/writing-bindings.txt b/Documentation/devicetree/bindings/writing-bindings.txt new file mode 100644 index 000000000000..27dfd2d8016e --- /dev/null +++ b/Documentation/devicetree/bindings/writing-bindings.txt @@ -0,0 +1,60 @@ +DOs and DON'Ts for designing and writing Devicetree bindings + +This is a list of common review feedback items focused on binding design. With +every rule, there are exceptions and bindings have many gray areas. + +For guidelines related to patches, see +Documentation/devicetree/bindings/submitting-patches.txt + + +Overall design + +- DO attempt to make bindings complete even if a driver doesn't support some + features. For example, if a device has an interrupt, then include the + 'interrupts' property even if the driver is only polled mode. + +- DON'T refer to Linux or "device driver" in bindings. Bindings should be + based on what the hardware has, not what an OS and driver currently support. + +- DO use node names matching the class of the device. Many standard names are + defined in the DT Spec. If there isn't one, consider adding it. + +- DO check that the example matches the documentation especially after making + review changes. + +- DON'T create nodes just for the sake of instantiating drivers. Multi-function + devices only need child nodes when the child nodes have their own DT + resources. A single node can be multiple providers (e.g. clocks and resets). + +- DON'T use 'syscon' alone without a specific compatible string. A 'syscon' + hardware block should have a compatible string unique enough to infer the + register layout of the entire block (at a minimum). + + +Properties + +- DO make 'compatible' properties specific. DON'T use wildcards in compatible + strings. DO use fallback compatibles when devices are the same as or a subset + of prior implementations. DO add new compatibles in case there are new + features or bugs. + +- DO use a vendor prefix on device specific property names. Consider if + properties could be common among devices of the same class. Check other + existing bindings for similar devices. + +- DON'T redefine common properties. Just reference the definition and define + constraints specific to the device. + +- DO use common property unit suffixes for properties with scientific units. + See property-units.txt. + +- DO define properties in terms of constraints. How many entries? What are + possible values? What is the order? + + +Board/SoC .dts Files + +- DO put all MMIO devices under a bus node and not at the top-level. + +- DO use non-empty 'ranges' to limit the size of child buses/devices. 64-bit + platforms don't need all devices to have 64-bit address and size. diff --git a/Documentation/devicetree/writing-schema.md b/Documentation/devicetree/writing-schema.md index a3652d33a48f..dc032db36262 100644 --- a/Documentation/devicetree/writing-schema.md +++ b/Documentation/devicetree/writing-schema.md @@ -97,7 +97,7 @@ The DT schema project must be installed in order to validate the DT schema binding documents and validate DTS files using the DT schema. The DT schema project can be installed with pip: -`pip3 install git+https://github.com/robherring/yaml-bindings.git@master` +`pip3 install git+https://github.com/devicetree-org/dt-schema.git@master` dtc must also be built with YAML output support enabled. This requires that libyaml and its headers be installed on the host system. |