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Diffstat (limited to 'Documentation/devicetree/bindings/submitting-patches.rst')
| -rw-r--r-- | Documentation/devicetree/bindings/submitting-patches.rst | 63 |
1 files changed, 43 insertions, 20 deletions
diff --git a/Documentation/devicetree/bindings/submitting-patches.rst b/Documentation/devicetree/bindings/submitting-patches.rst index 0aab2b3f16d0..ce767b1eccf2 100644 --- a/Documentation/devicetree/bindings/submitting-patches.rst +++ b/Documentation/devicetree/bindings/submitting-patches.rst @@ -1,23 +1,36 @@ .. SPDX-License-Identifier: GPL-2.0 ========================================== -Submitting devicetree (DT) binding patches +Submitting Devicetree (DT) binding patches ========================================== I. For patch submitters ======================= - 0) Normal patch submission rules from Documentation/process/submitting-patches.rst - applies. + 0) Normal patch submission rules from + Documentation/process/submitting-patches.rst applies. 1) The Documentation/ and include/dt-bindings/ portion of the patch should be a separate patch. The preferred subject prefix for binding patches is:: "dt-bindings: <binding dir>: ..." + Few subsystems, like ASoC, media, regulators and SPI, expect reverse order + of the prefixes:: + + "<binding dir>: dt-bindings: ..." + The 80 characters of the subject are precious. It is recommended to not - use "Documentation" or "doc" because that is implied. All bindings are - docs. Repeating "binding" again should also be avoided. + use "Documentation", "doc" or "YAML" because that is implied. All + bindings are docs and all new bindings are supposed to be in Devicetree + schema format. Repeating "binding" again should also be avoided, so for + a new device it is often enough for example:: + + "dt-bindings: iio: adc: Add ROHM BD79100G" + + Conversion of other formats to DT schema:: + + "dt-bindings: iio: adc: adi,ad7476: Convert to DT schema" 2) DT binding files are written in DT schema format using json-schema vocabulary and YAML file format. The DT binding files must pass validation @@ -25,7 +38,8 @@ I. For patch submitters make dt_binding_check - See ../writing-schema.rst for more details about schema and tools setup. + See Documentation/devicetree/bindings/writing-schema.rst for more details + about schema and tools setup. 3) DT binding files should be dual licensed. The preferred license tag is (GPL-2.0-only OR BSD-2-Clause). @@ -41,27 +55,31 @@ I. For patch submitters the code implementing the binding. 6) Any compatible strings used in a chip or board DTS file must be - previously documented in the corresponding DT binding text file + previously documented in the corresponding DT binding file in Documentation/devicetree/bindings. This rule applies even if the Linux device driver does not yet match on the compatible string. [ checkpatch will emit warnings if this step is not followed as of commit bff5da4335256513497cc8c79f9a9d1665e09864 ("checkpatch: add DT compatible string documentation checks"). ] - 7) The wildcard "<chip>" may be used in compatible strings, as in - the following example: - - - compatible: Must contain '"nvidia,<chip>-pcie", - "nvidia,tegra20-pcie"' where <chip> is tegra30, tegra132, ... + 7) DTS is treated in general as driver-independent hardware description, thus + any DTS patches, regardless whether using existing or new bindings, should + be placed at the end of patchset to indicate no dependency of drivers on + the DTS. DTS will be anyway applied through separate tree or branch, so + different order would indicate the series is non-bisectable. - As in the above example, the known values of "<chip>" should be - documented if it is used. + If a driver subsystem maintainer prefers to apply entire set, instead of + their relevant portion of patchset, please split the DTS patches into + separate patchset with a reference in changelog or cover letter to the + bindings submission on the mailing list. 8) If a documented compatible string is not yet matched by the driver, the documentation should also include a compatible - string that is matched by the driver (as in the "nvidia,tegra20-pcie" - example above). + string that is matched by the driver. + 9) Bindings are actively used by multiple projects other than the Linux + Kernel, extra care and consideration may need to be taken when making changes + to existing bindings. II. For kernel maintainers ========================== @@ -74,16 +92,21 @@ II. For kernel maintainers binding, and it hasn't received an Acked-by from the devicetree maintainers after a few weeks, go ahead and take it. - Subsystem bindings (anything affecting more than a single device) - then getting a devicetree maintainer to review it is required. + For subsystem bindings (anything affecting more than a single device), + getting a devicetree maintainer to review it is required. - 3) For a series going though multiple trees, the binding patch should be + 3) For a series going through multiple trees, the binding patch should be kept with the driver using the binding. + 4) The DTS files should however never be applied via driver subsystem tree, + but always via platform SoC trees on dedicated branches (see also + Documentation/process/maintainer-soc.rst). + III. Notes ========== - 0) Please see ...bindings/ABI.txt for details regarding devicetree ABI. + 0) Please see Documentation/devicetree/bindings/ABI.rst for details + regarding devicetree ABI. 1) This document is intended as a general familiarization with the process as decided at the 2013 Kernel Summit. When in doubt, the current word of the |