Re: [PATCH v2 01/12] dt-bindings: clock: qcom: Add bindings for PDM GP_MN clock divider
From: Krzysztof Kozlowski
Date: Tue Oct 27 2026 - 14:47:48 EST
On Mon, Oct 26, 2026 at 04:59:27PM +0530, Taniya Das wrote:
> Add device tree bindings for the Qualcomm Peripheral Web's PDM GP_MN
> clock divider. The hardware generates a fractional output frequency
> from a fixed input clock (typically TCXO4) using the relation
> Fout = Fin * (M / N), with duty cycle controlled by a separate D
> register. The clock output is routed over a gpio controlled pin.
>
> Signed-off-by: Taniya Das <taniya.das@xxxxxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/clock/qcom,clk-gp-mnd.yaml | 98 ++++++++++++++++++++++
> 1 file changed, 98 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/clock/qcom,clk-gp-mnd.yaml b/Documentation/devicetree/bindings/clock/qcom,clk-gp-mnd.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..8141f392c5d70acfc42cf1ff4b1722e1eff23afa
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/qcom,clk-gp-mnd.yaml
Use fallback as filename, so qcom,sc7280-gp-mnd.yaml
> @@ -0,0 +1,98 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/clock/qcom,clk-gp-mnd.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Peripheral Web's PDM GP_MN Clock Divider
> +
> +maintainers:
> + - Taniya Das <taniya.das@xxxxxxxxxxxxxxxx>
> +
> +description: |
> + The Peripheral Web's PDM GP_MN clock divider receives an input clock
> + (TCXO4) with frequency Fin and generates an output clock with
> + frequency Fout = Fin * (M / N) and a duty cycle controlled by D
> + and routed over a gpio pin.
> +
> + The divider is configured using three registers:
> +
> + - GP_MN_CLK_MDIV: holds the M value.
> + - GP_MN_CLK_NDIV: holds the ones complement of (N - M).
> + - GP_MN_CLK_DUTY: holds the D value.
> +
> + For every N input clock cycles the GP_MN produces M output clock
> + cycles. D is the number of native clock cycles in which the GP_MN
> + output is low, counted over 2^13 native clock cycles.
> +
> + Hardware constraints:
> +
> + M <= 511
> + N <= 8191
> + N > 2 * M
> + M < D < (N - M)
> + M and N must be coprime (no common divisor)
> +
> +properties:
> + compatible:
> + oneOf:
> + - const: qcom,sc7280-gp-mnd
> + - items:
> + - enum:
> + - qcom,sa8775p-gp-mnd
> + - qcom,qcs8300-gp-mnd
> + - qcom,qcs615-gp-mnd
> + - const: qcom,sc7280-gp-mnd
> +
> + reg:
> + maxItems: 1
> +
> + clocks:
> + items:
> + - description: PDM XO4 source clock
> + - description: PDM AHB bus clock for register access
> +
> + clock-names:
> + items:
> + - const: pdm_clk
pdm
> + - const: ahb_clk
ahb
> +
> + '#clock-cells':
> + const: 0
> +
> + assigned-clocks:
> + maxItems: 1
> + description: Parent clock phandle used to set the input frequency.
> +
> + assigned-clock-rates:
> + maxItems: 1
> + description: |
> + Rate for the parent clock in Hz.
> + Supported rates: 19200000, 9600000, 6400000, 4800000.
Neither assigned-clocks nor assigned-clock-rates should be needed.
Parent clock is outside of scope of this binding.
> +
> +required:
> + - compatible
> + - reg
> + - clocks
> + - clock-names
> + - '#clock-cells'
> + - assigned-clocks
> + - assigned-clock-rates
And these two should not be required, either.
Best regards,
Krzysztof