[PATCH v9 2/5] mfd: AXP20x: Add bindings documentation

Chen-Yu Tsai wens at csie.org
Sat Jan 31 08:49:38 PST 2015


Hi Lee,

On Thu, Jan 22, 2015 at 5:02 PM, Lee Jones <lee.jones at linaro.org> wrote:
> On Thu, 22 Jan 2015, Chen-Yu Tsai wrote:
>
>> From: Carlo Caione <carlo at caione.org>
>>
>> Bindings documentation for the AXP20x driver. In this file also
>> sub-nodes are documented.
>>
>> Signed-off-by: Carlo Caione <carlo at caione.org>
>> Acked-by: Maxime Ripard <maxime.ripard at free-electrons.com>
>> [wens at csie.org: clarify interrupt source for the axp PMIC]
>> [wens at csie.org: explain dcdc-workmode in detail and trim lines to 80 chars]
>> [wens at csie.org: make regulator supplies optional if using unregulated input]
>> [wens at csie.org: use cubieboard2 regulator nodes as example]
>> [wens at csie.org: change dcdc-workmode to dcdc-workmode-pwm boolean property]
>> [wens at csie.org: use clock-frequency for dcdc regulator work frequency]
>> Signed-off-by: Chen-Yu Tsai <wens at csie.org>
>> ---
>>  Documentation/devicetree/bindings/mfd/axp20x.txt | 102 +++++++++++++++++++++++
>>  1 file changed, 102 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/mfd/axp20x.txt
>
> This looks okay to me now.
>
> If Mark is happy with the remainder, I'll merge this.

So Mark is not happy with this actually, for a few reasons:

1. The driver was already merged a couple versions back, and
   we have been using the dcdc-freq binding.

2. Furthermore, the dcdc-freq binding has nothing to do with
   the common clock framework. Using the clock-frequencies
   binding implies it does.

3. The change from a integer value to a boolean flag for
   dcdc-mode makes it less capable, i.e. the kernel can't
   just accept the current state of the hardware, which
   should be a valid option for regulators to not screw
   up the system accidentally.

Any chance you could merge the previous version (v8)?


Regards,
ChenYu

> For my own reference:
> Acked-by: Lee Jones <lee.jones at linaro.org>
>
>> diff --git a/Documentation/devicetree/bindings/mfd/axp20x.txt b/Documentation/devicetree/bindings/mfd/axp20x.txt
>> new file mode 100644
>> index 000000000000..c3c80db242c7
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/mfd/axp20x.txt
>> @@ -0,0 +1,102 @@
>> +AXP202/AXP209 device tree bindings
>> +
>> +The axp20x family current members :
>> +axp202 (X-Powers)
>> +axp209 (X-Powers)
>> +
>> +Required properties:
>> +- compatible: "x-powers,axp202" or "x-powers,axp209"
>> +- reg: The I2C slave address for the AXP chip
>> +- interrupt-parent: The parent interrupt controller
>> +- interrupts: SoC NMI / GPIO interrupt connected to the PMIC's IRQ pin
>> +- interrupt-controller: axp20x has its own internal IRQs
>> +- #interrupt-cells: Should be set to 1
>> +- regulators: A node that houses a sub-node for each regulator. The regulators
>> +           are bound using their name as listed here: dcdc2, dcdc3, ldo1,
>> +           ldo2, ldo3, ldo4, ldo5.  The bindings details of individual
>> +           regulator device can be found in:
>> +           Documentation/devicetree/bindings/regulator/regulator.txt with
>> +           the exception of x-powers,dcdc-freq. Regulators not used should
>> +           still be listed for completeness and that the regulator subsystem
>> +           properly registers them.
>> +
>> +Optional properties:
>> +- regulator supplies - may be omitted if inputs are unregulated, such as using
>> +                    the IPSOUT output from the PMIC
>> +  - acin-supply: The input supply for LDO1
>> +  - vin2-supply: The input supply for DCDC2
>> +  - vin3-supply: The input supply for DCDC3
>> +  - ldo24in-supply: The input supply for LDO2, LDO4
>> +  - ldo3in-supply: The input supply for LDO3
>> +  - ldo5in-supply: The input supply for LDO5
>> +
>> +Optional properties for regulators node:
>> +- clock-frequency: defines the work frequency of DC-DC regulators
>> +                (range: 750kHz - 1875kHz). Default: 1.5MHz
>> +
>> +Optional properties for DCDC regulators:
>> +- x-powers,dcdc-workmode-pwm: Force the DCDC regulators to run in PWM mode
>> +                           The DCDC regulators rormally work in a mixed
>> +                           PWM/PFM mode, using PFM under light loads and
>> +                           switching to PWM for heavier loads. Forcing
>> +                           PWM mode trades efficiency under light loads
>> +                           for lower output noise. This probably makes
>> +                           sense for HiFi audio related applications that
>> +                           aren't battery constrained.
>> +
>> +Example:
>> +
>> +axp209: pmic at 34 {
>> +     compatible = "x-powers,axp209";
>> +     reg = <0x34>;
>> +     interrupt-parent = <&nmi_intc>;
>> +     interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
>> +     interrupt-controller;
>> +     #interrupt-cells = <1>;
>> +
>> +     regulators {
>> +             clock-frequency = <1500000>;
>> +
>> +             vdd_cpu: dcdc2 {
>> +                     regulator-always-on;
>> +                     regulator-min-microvolt = <1000000>;
>> +                     regulator-max-microvolt = <1450000>;
>> +                     regulator-name = "vdd-cpu";
>> +             };
>> +
>> +             vdd_int_dll: dcdc3 {
>> +                     regulator-always-on;
>> +                     regulator-min-microvolt = <1000000>;
>> +                     regulator-max-microvolt = <1400000>;
>> +                     regulator-name = "vdd-int-dll";
>> +             };
>> +
>> +             vdd_rtc: ldo1 {
>> +                     regulator-always-on;
>> +                     regulator-min-microvolt = <1200000>;
>> +                     regulator-max-microvolt = <1400000>;
>> +                     regulator-name = "vdd-rtc";
>> +             };
>> +
>> +             avcc: ldo2 {
>> +                     regulator-always-on;
>> +                     regulator-min-microvolt = <2700000>;
>> +                     regulator-max-microvolt = <3300000>;
>> +                     regulator-name = "avcc";
>> +             };
>> +
>> +             ldo3 {
>> +                     /* unused */
>> +             };
>> +
>> +             csi1_io_2v8: ldo4 {
>> +                     /* output on extension headers */
>> +                     regulator-name = "csi1-io-2v8";
>> +             };
>> +
>> +             ldo5 {
>> +                     /* unused */
>> +             };
>> +     };
>> +};
>> +
>
> --
> Lee Jones
> Linaro STMicroelectronics Landing Team Lead
> Linaro.org │ Open source software for ARM SoCs
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