[v2,01/15] dt-bindings: ufs: add common platform bindings

Add bindings for common parts (platform) of Universal Flash Storage
(UFS) Host Controllers in dtschema format.

The 'freq-table-hz' is not correct in dtschema, because '-hz' suffix
defines uint32 type, not an array.  Therefore deprecate 'freq-table-hz'
and use 'freq-table' instead.

Include also the bindings directory in UFS maintainers entry.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
---
 .../devicetree/bindings/ufs/ti,j721e-ufs.yaml |  2 +-
 .../devicetree/bindings/ufs/ufs-common.yaml   | 88 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 3 files changed, 90 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/ufs/ufs-common.yaml

On Tue, Feb 22, 2022 at 03:58:40PM +0100, Krzysztof Kozlowski wrote:
> Add bindings for common parts (platform) of Universal Flash Storage
> (UFS) Host Controllers in dtschema format.
> 
> The 'freq-table-hz' is not correct in dtschema, because '-hz' suffix
> defines uint32 type, not an array.  Therefore deprecate 'freq-table-hz'
> and use 'freq-table' instead.

-hz is an array type. We can extend it to matrix if needed.

I do think this property is a bit questionable. Do we really need a 
minimum in DT and if not, wouldn't assigned-clocks-rate work? Or an OPP 
table.

> Include also the bindings directory in UFS maintainers entry.
> 
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
> ---
>  .../devicetree/bindings/ufs/ti,j721e-ufs.yaml |  2 +-
>  .../devicetree/bindings/ufs/ufs-common.yaml   | 88 +++++++++++++++++++
>  MAINTAINERS                                   |  1 +
>  3 files changed, 90 insertions(+), 1 deletion(-)
>  create mode 100644 Documentation/devicetree/bindings/ufs/ufs-common.yaml
> 
> diff --git a/Documentation/devicetree/bindings/ufs/ti,j721e-ufs.yaml b/Documentation/devicetree/bindings/ufs/ti,j721e-ufs.yaml
> index 4d13e6bc1c50..dc93fe2d3458 100644
> --- a/Documentation/devicetree/bindings/ufs/ti,j721e-ufs.yaml
> +++ b/Documentation/devicetree/bindings/ufs/ti,j721e-ufs.yaml
> @@ -80,7 +80,7 @@ examples:
>                  compatible = "cdns,ufshc-m31-16nm", "jedec,ufs-2.0";
>                  reg = <0x0 0x4000 0x0 0x10000>;
>                  interrupts = <GIC_SPI 17 IRQ_TYPE_LEVEL_HIGH>;
> -                freq-table-hz = <19200000 19200000>;
> +                freq-table = <19200000 19200000>;
>                  power-domains = <&k3_pds 277>;
>                  clocks = <&k3_clks 277 1>;
>                  assigned-clocks = <&k3_clks 277 1>;
> diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> new file mode 100644
> index 000000000000..85c73d2853e9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> @@ -0,0 +1,88 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/ufs/ufs-common.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Common properties for Universal Flash Storage (UFS) Host Controllers
> +
> +maintainers:
> +  - Alim Akhtar <alim.akhtar@samsung.com>
> +  - Avri Altman <avri.altman@wdc.com>
> +
> +properties:
> +  clocks: true
> +
> +  clock-names: true
> +
> +  freq-table-hz:
> +    deprecated: true
> +    description:
> +      Use freq-table.
> +
> +  freq-table:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    items:
> +      items:
> +        - description: Minimum frequency for given clock
> +        - description: Maximum frequency for given clock
> +    description: |
> +      Array of <min max> operating frequencies in Hz stored in the same order
> +      as the clocks property. If this property is not defined or a value in the
> +      array is "0" then it is assumed that the frequency is set by the parent
> +      clock or a fixed rate clock source.
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  lanes-per-direction:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [1, 2]
> +    default: 2
> +    description:
> +      Number of lanes available per direction.  Note that it is assume same
> +      number of lanes is used both directions at once.
> +
> +  vdd-hba-supply:
> +    description:
> +      Phandle to UFS host controller supply regulator node.
> +
> +  vcc-supply:
> +    description:
> +      Phandle to VCC supply regulator node.
> +
> +  vccq-supply:
> +    description:
> +      Phandle to VCCQ supply regulator node.
> +
> +  vccq2-supply:
> +    description:
> +      Phandle to VCCQ2 supply regulator node.
> +
> +  vcc-supply-1p8:
> +    type: boolean
> +    description:
> +      For embedded UFS devices, valid VCC range is 1.7-1.95V or 2.7-3.6V. This
> +      boolean property when set, specifies to use low voltage range of
> +      1.7-1.95V. Note for external UFS cards this property is invalid and valid
> +      VCC range is always 2.7-3.6V.
> +
> +  vcc-max-microamp:
> +    description:
> +      Specifies max. load that can be drawn from VCC supply.
> +
> +  vccq-max-microamp:
> +    description:
> +      Specifies max. load that can be drawn from VCCQ supply.
> +
> +  vccq2-max-microamp:
> +    description:
> +      Specifies max. load that can be drawn from VCCQ2 supply.
> +
> +dependencies:
> +  freq-table: [ 'clocks' ]
> +
> +required:
> +  - interrupts
> +
> +additionalProperties: true
> diff --git a/MAINTAINERS b/MAINTAINERS
> index aa0f6cbb634e..c2cff57d32f8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -20015,6 +20015,7 @@ R:	Alim Akhtar <alim.akhtar@samsung.com>
>  R:	Avri Altman <avri.altman@wdc.com>
>  L:	linux-scsi@vger.kernel.org
>  S:	Supported
> +F:	Documentation/devicetree/bindings/ufs/
>  F:	Documentation/scsi/ufs.rst
>  F:	drivers/scsi/ufs/
>  
> -- 
> 2.32.0
> 
>

On 25/02/2022 20:26, Rob Herring wrote:
> On Tue, Feb 22, 2022 at 03:58:40PM +0100, Krzysztof Kozlowski wrote:
>> Add bindings for common parts (platform) of Universal Flash Storage
>> (UFS) Host Controllers in dtschema format.
>>
>> The 'freq-table-hz' is not correct in dtschema, because '-hz' suffix
>> defines uint32 type, not an array.  Therefore deprecate 'freq-table-hz'
>> and use 'freq-table' instead.
> 
> -hz is an array type. We can extend it to matrix if needed.
> 
> I do think this property is a bit questionable. Do we really need a 
> minimum in DT and if not, wouldn't assigned-clocks-rate work? Or an OPP 
> table.
> 

I think the proper solution is OPP table, see also comments from Bjorn:
https://lore.kernel.org/all/YhUodbzxx4wbr+gy@ripper/

I would rather refrain from converting it to OPP tables, because I won't
be able to test any changes in the driver.


Best regards,
Krzysztof