Re: [PATCH] dt-bindings: mmc: sdhci-omap: convert text based binding to json schema

[Krzysztof Kozlowski <krzk@kernel.org>]

On 23/05/2025 19:05, Charan Pedumuru wrote:
> Convert TI OMAP SDHCI Controller binding to YAML format.
> Changes during Conversion:
> - Add patternProperties for pinctrl-<n>.
> - Define new properties like "ti,hwmods", "ti,needs-special-reset"
>   "ti,needs-special-hs-handling", "cap-mmc-dual-data-rate"
>   and "pbias-supply".

Why? commit should answer this.

> - Remove "ti,hwmods", "pinctrl-names" and "pinctrl-<n>"

Why? You just added ti,hwmods, so how can you remove it from required?

>   from required as they are not necessary for all DTS files.
> - Add missing strings like "default-rev11", "sdr12-rev11", "sdr25-rev11",
>   "hs-rev11", "sdr25-rev11" and "sleep" to pinctrl-names string array.
> 
> Signed-off-by: Charan Pedumuru <charan.pedumuru@gmail.com>
> ---
>  .../devicetree/bindings/mmc/sdhci-omap.txt         |  43 ------
>  .../devicetree/bindings/mmc/sdhci-omap.yaml        | 155 +++++++++++++++++++++


Filename: ti,omap-sdhci.yaml or one of the compatibles (or anything else
following convention that it should match compatible).


"ti,needs-special-hs-handling" is already documented in other binding


>  2 files changed, 155 insertions(+), 43 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/sdhci-omap.txt b/Documentation/devicetree/bindings/mmc/sdhci-omap.txt
> deleted file mode 100644
> index f91e341e6b36c410275e6f993dd08400be3fc1f8..0000000000000000000000000000000000000000
> --- a/Documentation/devicetree/bindings/mmc/sdhci-omap.txt
> +++ /dev/null
> @@ -1,43 +0,0 @@
> -* TI OMAP SDHCI Controller


...


> diff --git a/Documentation/devicetree/bindings/mmc/sdhci-omap.yaml b/Documentation/devicetree/bindings/mmc/sdhci-omap.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..e707837bc242b055bbc497ed893a91c9b24f2dde
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/sdhci-omap.yaml
> @@ -0,0 +1,155 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mmc/sdhci-omap.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: TI OMAP SDHCI Controller
> +
> +maintainers:
> +  - Ulf Hansson <ulf.hansson@linaro.org>

This is supposed to be someone caring about this device. Eventually
platform maintainer.

> +
> +description:
> +  For UHS devices which require tuning, the device tree should have a
> +  cpu_thermal node which maps to the appropriate thermal zone. This
> +  is used to get the temperature of the zone during tuning.
> +
> +allOf:
> +  - $ref: sdhci-common.yaml#
> +
> +properties:
> +  compatible:
> +    enum:
> +      - ti,omap2430-sdhci
> +      - ti,omap3-sdhci
> +      - ti,omap4-sdhci
> +      - ti,omap5-sdhci
> +      - ti,dra7-sdhci
> +      - ti,k2g-sdhci
> +      - ti,am335-sdhci
> +      - ti,am437-sdhci
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  pinctrl-names:
> +    $ref: /schemas/types.yaml#/definitions/string-array
> +    minItems: 1
> +    maxItems: 19
> +    items:
> +      enum:
> +        - default
> +        - default-rev11
> +        - hs
> +        - sdr12
> +        - sdr12-rev11
> +        - sdr25
> +        - sdr25-rev11
> +        - sdr50
> +        - ddr50-rev11
> +        - sdr104-rev11
> +        - ddr50
> +        - sdr104
> +        - ddr_1_8v-rev11
> +        - ddr_1_8v
> +        - ddr_3_3v
> +        - hs-rev11
> +        - hs200_1_8v-rev11
> +        - hs200_1_8v
> +        - sleep
> +
> +  dmas:
> +    maxItems: 2
> +
> +  dma-names:
> +    items:
> +      - const: tx
> +      - const: rx
> +
> +  ti,hwmods:
> +    $ref: /schemas/types.yaml#/definitions/string
> +    description:
> +      This field is used to fetch the information such as
> +      address range, irq lines, dma lines, interconnect, PRCM register,
> +      clock domain, input clocks associated with MMC.
> +    pattern: "^mmc[0-9]+$"
> +
> +  ti,needs-special-reset:

I don't understand why you added this. There is no user of it.

> +    description:
> +      It indicates that a specific soft reset sequence is required for
> +      certain Texas Instruments devices, particularly those with
> +      HSMMC (High-Speed MultiMediaCard) controllers.
> +    type: boolean
> +
> +  ti,needs-special-hs-handling:

I don't understand why you added this. There is no user of it.


> +    description:
> +      It's presence in an MMC controller's DT node signals to the Linux kernel's
> +      omap_hsmmc driver that this particular IP block requires special software
> +      handling or workarounds to correctly manage High-Speed (HS) modes like
> +      SDR25, SDR50, SDR104, DDR50.
> +    type: boolean
> +
> +  pbias-supply:
> +    description:
> +      It is used to specify the voltage regulator that provides the bias
> +      voltage for certain analog or I/O pads.
> +
> +  cap-mmc-dual-data-rate:
> +    description:
> +      A characteristic or capability associated with MultiMediaCard (MMC)
> +      interfaces, specifically indicating that the MMC controller
> +      supports Dual Data Rate (DDR) mode

Drop the property. We have standard properties for this and there is no
ABI for it anyway.

> +    type: boolean
> +
> +  ti,non-removable:
> +    description:
> +      It indicates that a component is not meant to be easily removed or
> +      replaced by the user, such as an embedded battery or a non-removable
> +      storage slot like eMMC.
> +    type: boolean
> +    deprecated: true
> +
> +  vmmmc-supply:
> +    description:
> +      It is used to specify the power supply (regulator) for the MMC/SD card's
> +      main operating voltage (VCC/VDD).
> +
> +  clock-frequency:

Why is it here? Nothing in commit msg explained adding it.

> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      It is used to specify the frequency of a clock in Hertz (Hz). It's a
> +      fundamental property for communicating hardware clocking information from
> +      the Device Tree to the Linux kernel.

Redundant description. It is not a fundamental property. It is a legacy
property.

> +
> +patternProperties:
> +  "^pinctrl-[0-9]+$":
> +    $ref: /schemas/types.yaml#/definitions/phandle-array
> +    description:
> +      Phandles to pinctrl states. The numeric suffix determines the
> +      state index corresponding to entries in the pinctrl-names array.
> +    minItems: 1

Why exactly do you need these?

> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +
> +unevaluatedProperties: false
> +
Best regards,
Krzysztof