| Message ID | 9275af790e6e21b5cf661a2444effe4caf2be02e.1681646904.git.jahau@rocketmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add RT5033 charger device driver | expand |
Hi Linus! On 20.04.23 10:03, Linus Walleij wrote: > On Thu, Apr 20, 2023 at 9:59 AM Linus Walleij <linus.walleij@linaro.org> wrote: >> >> Hi Jakob, >> >> thanks for your patch! >> >> The following caught my eye: >> >> On Sun, Apr 16, 2023 at 2:50 PM Jakob Hauser <jahau@rocketmail.com> wrote: >> >>> Add device tree binding documentation for rt5033 multifunction device, voltage >>> regulator and battery charger. >>> >>> Cc: Beomho Seo <beomho.seo@samsung.com> >>> Cc: Chanwoo Choi <cw00.choi@samsung.com> >>> Signed-off-by: Jakob Hauser <jahau@rocketmail.com> >>> --- >>> The patch is based on linux-next (tag "next-20230413"). >> (...) >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/power/supply/richtek,rt5033-charger.yaml >> (...) >>> + richtek,pre-microamp: >>> + description: >>> + Current of pre-charge mode. The pre-charge current levels are 350 mA to >>> + 650 mA programmed by I2C per 100 mA. >>> + maxItems: 1 >>> + >>> + richtek,fast-microamp: >>> + description: >>> + Current of fast-charge mode. The fast-charge current levels are 700 mA >>> + to 2000 mA programmed by I2C per 100 mA. >>> + maxItems: 1 >>> + >>> + richtek,eoc-microamp: >>> + description: >>> + This property is end of charge current. Its level ranges from 150 mA to >>> + 600 mA. Between 150 mA and 300 mA in 50 mA steps, between 300 mA and 600 mA >>> + in 100 mA steps. >>> + maxItems: 1 >>> + >>> + richtek,pre-threshold-microvolt: >>> + description: >>> + Voltage of pre-charge mode. If the battery voltage is below the pre-charge >>> + threshold voltage, the charger is in pre-charge mode with pre-charge current. >>> + Its levels are 2.3 V to 3.8 V programmed by I2C per 0.1 V. >>> + maxItems: 1 >>> + >>> + richtek,const-microvolt: >>> + description: >>> + Battery regulation voltage of constant voltage mode. This voltage levels from >>> + 3.65 V to 4.4 V by I2C per 0.025 V. >>> + maxItems: 1 >> >> These are very generic currents and voltages, and their usage is well known >> and generic. So they should not be prefixed "richtek,". >> >> Use the properties already defined in >> Documentation/devicetree/bindings/power/supply/battery.yaml >> for these: >> >> precharge-current-microamp >> constant-charge-current-max-microamp >> charge-term-current-microamp >> precharge-upper-limit-microvolt >> constant-charge-voltage-max-microvolt >> >> Please double-check, I think those are the ones you need. >> >> Perhaps it is possible to just $ref these properties directly and add >> the additional restrictions on top. > > On second thought, these are really weird properties to have on the > *charger* isn't it? > > It is really *battery* restrictions. > > A charger can charge many different batteries with different CC/CV > settings. > > I think your charger should contain a phandle to a battery and the battery > node should contain these limits. > > monitored-battery: > $ref: /schemas/types.yaml#/definitions/phandle > description: phandle to battery node > > Then you can just use the standard battery bindings for these properties > on the battery. > > See for example: > Documentation/devicetree/bindings/power/supply/stericsson,ab8500-charger.yaml > > There will be driver changes needed too, but this will be way cleaner. > > Yours, > Linus Walleij These are interesting hints! I was first a bit confused by the term "battery". I associated that term with the driver "rt5033-battery". But I think that thought was wrong. The driver "rt5033-battery" is just the fuel gauge. Hardware-wise, the mfd (incl. charger) and fuel gauge are on different I2C lines. Therefore, the different drivers access different registers. Charger registers: https://github.com/torvalds/linux/blob/v6.3-rc7/include/linux/mfd/rt5033-private.h#L13-L23 Fuel gauge registers: https://github.com/torvalds/linux/blob/v6.3-rc7/include/linux/mfd/rt5033-private.h#L215-L243 The things being set or read in those registers kind of determine which things are done in which driver. The properties we talk about here are the settings for the charger. They tell the charger how it should behave. It makes sense to process those settings within the charger driver. The fuel gauge, on the other hand, returns information like actual voltage and percentage. The only thing that seems not placed well is the "status" property like charging/discharging/not-charging/etc. At RT5033 this information is within the charger register. Userspace layer "UPower" expects this from the "battery" device. Patch 8 of this series v2 carries that property from the charger over to the fuel gauge. Though this is a bit of a quirk. And it creates dependencies between two drivers which actually would be independent from each other. --------------------------------- Back to the topic. When we talk about "battery" here, it seems to me that it's about the representation in the devicetree. Currently it is: pmic@34 { compatible = "richtek,rt5033"; .... charger { compatible = "richtek,rt5033-charger"; richtek,pre-microamp = <450000>; richtek,fast-microamp = <1000000>; richtek,eoc-microamp = <150000>; richtek,pre-threshold-microvolt = <3500000>; richtek,const-microvolt = <4350000>; extcon = <&muic>; }; }; According to your remarks, the properties could be "outsourced" into a battery node. (Btw. I have double-checked the property names.) battery: battery { compatible = "simple-battery"; precharge-current-microamp = <450000>; constant-charge-current-max-microamp = <1000000>; charge-term-current-microamp = <150000>; precharge-upper-limit-microvolt = <3500000>; constant-charge-voltage-max-microvolt = <4350000>; }; pmic@34 { compatible = "richtek,rt5033"; .... charger { compatible = "richtek,rt5033-charger"; monitored-battery = <&battery>; extcon = <&muic>; }; }; Personally I would choose the current implementation for two reasons (possibly weak ones): 1) The original author of the driver and documentation is Beomho Seo. I tried to preserve the original structure as far as possible. This is probably rather a question of editing than a technical one. 2) At least in my mind it's still the setup for the charger. It sets up a the charging behavior of a certain consumer device. And the choice of their values is limited to the hardware of the charger. Accordingly the dt-bindings would say what the charger hardware is capable to do. Therefore I'd say it's reasonable to have those values in the charger node and use vendor properties. I agree to you that actually the physical battery is determining how these values should be set. In the end, as far as I can see, it is a representation thing in the devicetree. At least in our case here. Not sure how to proceed here. I would stick to the current implementation. If someone strongly prefers the "battery" representation style, I'm open to switch to this. However, I'm not sure how the dt-bindings would look like in that case. Those battery properties would not be part of the RT5033 node, thus they basically would not be part of the RT5033 documentation. Again I think it makes sense to handle those properties within the charger node as "charger settings" properties. Kind regards, Jakob
Hi Linus, On 21.04.23 11:20, Linus Walleij wrote: > On Thu, Apr 20, 2023 at 11:16 PM Jakob Hauser <jahau@rocketmail.com> wrote: ... >> I agree to you that actually the physical battery is determining how >> these values should be set. In the end, as far as I can see, it is a >> representation thing in the devicetree. At least in our case here. > > The DT bindings should reflect the hardware, and not what some > or any driver "would like to see" (to make its life easier...) > > As these things are programmed into registers, clearly the > hardware is adoptable for different batteries, and the purpose > of these registers is to support different batteries. Ergo: they > belong in a battery node. > >> Not sure how to proceed here. I would stick to the current >> implementation. If someone strongly prefers the "battery" representation >> style, I'm open to switch to this. > > Again this is not an implementation but a hardware description. > > It should use a phandle to a montored-battery and follow that to > read the battery properties. OK, this is expressing a strong preference. I’ll switch to the "battery" node in v3. >> However, I'm not sure how the dt-bindings would look like in that case. > > Just like you sketched above, just reuse simple-battery if the battery > is hardcoded into the platform, such as soldered in or has a form > factor such that no different battery can be fitted. > >> Those battery properties would not be part of the RT5033 node, thus they >> basically would not be part of the RT5033 documentation. Again I think >> it makes sense to handle those properties within the charger node as >> "charger settings" properties. > > Why? > > This is like saying that the number of pixels on your monitor should > be part of the graphics card DT node as "configuration". And we > clearly do not do that. The charger driver needs five parameters. And the person writing the dts file should know about what range and granularity is possible for those values. This information could be put into the description of the "monitored-battery", as shown below, but that's less strict and clear as it is currently in patch 9. title: Richtek RT5033 PIMC Battery Charger maintainers: - Jakob Hauser <jahau@rocketmail.com> description: The battery charger of the multifunction device RT5033 has to be instantiated under sub-node named "charger" using the following format. properties: compatible: const: richtek,rt5033-charger monitored-battery: description: | Phandle to the monitored battery according to battery.yaml. The battery node needs to contain five parameters. precharge-current-microamp: Current of pre-charge mode. The pre-charge current levels are 350 mA to 650 mA programmed by I2C per 100 mA. constant-charge-current-max-microamp: Current of fast-charge mode. The fast-charge current levels are 700 mA to 2000 mA programmed by I2C per 100 mA. charge-term-current-microamp: This property is end of charge current. Its level ranges from 150 mA to 600 mA. Between 150 mA and 300 mA in 50 mA steps, between 300 mA and 600 mA in 100 mA steps. precharge-upper-limit-microvolt: Voltage of pre-charge mode. If the battery voltage is below the pre-charge threshold voltage, the charger is in pre-charge mode with pre-charge current. Its levels are 2.3 V to 3.8 V programmed by I2C per 0.1 V. constant-charge-voltage-max-microvolt: Battery regulation voltage of constant voltage mode. This voltage levels from 3.65 V to 4.4 V by I2C per 0.025 V. extcon: description: Phandle to the extcon device. maxItems: 1 required: - monitored-battery additionalProperties: false examples: - | charger { compatible = "richtek,rt5033-charger"; monitored-battery = <&battery>; extcon = <&muic>; }; Kind regards, Jakob
diff --git a/Documentation/devicetree/bindings/mfd/richtek,rt5033.yaml b/Documentation/devicetree/bindings/mfd/richtek,rt5033.yaml new file mode 100644 index 000000000000..158036a57291 --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/richtek,rt5033.yaml @@ -0,0 +1,90 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/mfd/richtek,rt5033.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Richtek RT5033 Power Management Integrated Circuit + +maintainers: + - Jakob Hauser <jahau@rocketmail.com> + +description: + RT5033 is a multifunction device which includes battery charger, fuel gauge, + flash LED current source, LDO and synchronous Buck converter for portable + applications. It is interfaced to host controller using I2C interface. The + battery fuel gauge uses a separate I2C bus. + +properties: + compatible: + const: richtek,rt5033 + + reg: + maxItems: 1 + + interrupts: + maxItems: 1 + + regulators: + type: object + $ref: /schemas/regulator/richtek,rt5033-regulator.yaml# + + charger: + type: object + $ref: /schemas/power/supply/richtek,rt5033-charger.yaml# + +required: + - compatible + - reg + - interrupts + +additionalProperties: false + +examples: + - | + #include <dt-bindings/interrupt-controller/irq.h> + + i2c { + #address-cells = <1>; + #size-cells = <0>; + + pmic@34 { + compatible = "richtek,rt5033"; + reg = <0x34>; + + interrupt-parent = <&msmgpio>; + interrupts = <62 IRQ_TYPE_EDGE_FALLING>; + + pinctrl-names = "default"; + pinctrl-0 = <&pmic_int_default>; + + regulators { + safe_ldo_reg: safe_ldo { + regulator-name = "safe_ldo"; + regulator-min-microvolt = <4900000>; + regulator-max-microvolt = <4900000>; + regulator-always-on; + }; + ldo_reg: ldo { + regulator-name = "ldo"; + regulator-min-microvolt = <2800000>; + regulator-max-microvolt = <2800000>; + }; + buck_reg: buck { + regulator-name = "buck"; + regulator-min-microvolt = <1200000>; + regulator-max-microvolt = <1200000>; + }; + }; + + charger { + compatible = "richtek,rt5033-charger"; + richtek,pre-microamp = <450000>; + richtek,fast-microamp = <1000000>; + richtek,eoc-microamp = <150000>; + richtek,pre-threshold-microvolt = <3500000>; + richtek,const-microvolt = <4350000>; + extcon = <&muic>; + }; + }; + }; diff --git a/Documentation/devicetree/bindings/power/supply/richtek,rt5033-charger.yaml b/Documentation/devicetree/bindings/power/supply/richtek,rt5033-charger.yaml new file mode 100644 index 000000000000..439e0b7962f3 --- /dev/null +++ b/Documentation/devicetree/bindings/power/supply/richtek,rt5033-charger.yaml @@ -0,0 +1,76 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/power/supply/richtek,rt5033-charger.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Richtek RT5033 PIMC Battery Charger + +maintainers: + - Jakob Hauser <jahau@rocketmail.com> + +description: + The battery charger of the multifunction device RT5033 has to be instantiated + under sub-node named "charger" using the following format. + +properties: + compatible: + const: richtek,rt5033-charger + + richtek,pre-microamp: + description: + Current of pre-charge mode. The pre-charge current levels are 350 mA to + 650 mA programmed by I2C per 100 mA. + maxItems: 1 + + richtek,fast-microamp: + description: + Current of fast-charge mode. The fast-charge current levels are 700 mA + to 2000 mA programmed by I2C per 100 mA. + maxItems: 1 + + richtek,eoc-microamp: + description: + This property is end of charge current. Its level ranges from 150 mA to + 600 mA. Between 150 mA and 300 mA in 50 mA steps, between 300 mA and 600 mA + in 100 mA steps. + maxItems: 1 + + richtek,pre-threshold-microvolt: + description: + Voltage of pre-charge mode. If the battery voltage is below the pre-charge + threshold voltage, the charger is in pre-charge mode with pre-charge current. + Its levels are 2.3 V to 3.8 V programmed by I2C per 0.1 V. + maxItems: 1 + + richtek,const-microvolt: + description: + Battery regulation voltage of constant voltage mode. This voltage levels from + 3.65 V to 4.4 V by I2C per 0.025 V. + maxItems: 1 + + extcon: + description: + Phandle to the extcon device. + maxItems: 1 + +required: + - richtek,pre-microamp + - richtek,fast-microamp + - richtek,eoc-microamp + - richtek,pre-threshold-microvolt + - richtek,const-microvolt + +additionalProperties: false + +examples: + - | + charger { + compatible = "richtek,rt5033-charger"; + richtek,pre-microamp = <450000>; + richtek,fast-microamp = <1000000>; + richtek,eoc-microamp = <150000>; + richtek,pre-threshold-microvolt = <3500000>; + richtek,const-microvolt = <4350000>; + extcon = <&muic>; + }; diff --git a/Documentation/devicetree/bindings/regulator/richtek,rt5033-regulator.yaml b/Documentation/devicetree/bindings/regulator/richtek,rt5033-regulator.yaml new file mode 100644 index 000000000000..66c8a0692e10 --- /dev/null +++ b/Documentation/devicetree/bindings/regulator/richtek,rt5033-regulator.yaml @@ -0,0 +1,24 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/regulator/richtek,rt5033-regulator.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Richtek RT5033 PIMC Voltage Regulator + +maintainers: + - Jakob Hauser <jahau@rocketmail.com> + +description: + The regulators of RT5033 have to be instantiated under a sub-node named + "regulators". For "safe_ldo" voltage there is only one value of 4.9 V. "ldo" + voltage ranges from 1.2 V to 3.0 V in 0.1 V steps. "buck" voltage ranges from + 1.0 V to 3.0 V in 0.1 V steps. + +patternProperties: + "^(safe_ldo|ldo|buck)$": + type: object + $ref: /schemas/regulator/regulator.yaml# + unevaluatedProperties: false + +additionalProperties: false
Add device tree binding documentation for rt5033 multifunction device, voltage regulator and battery charger. Cc: Beomho Seo <beomho.seo@samsung.com> Cc: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Jakob Hauser <jahau@rocketmail.com> --- The patch is based on linux-next (tag "next-20230413"). .../bindings/mfd/richtek,rt5033.yaml | 90 +++++++++++++++++++ .../power/supply/richtek,rt5033-charger.yaml | 76 ++++++++++++++++ .../regulator/richtek,rt5033-regulator.yaml | 24 +++++ 3 files changed, 190 insertions(+) create mode 100644 Documentation/devicetree/bindings/mfd/richtek,rt5033.yaml create mode 100644 Documentation/devicetree/bindings/power/supply/richtek,rt5033-charger.yaml create mode 100644 Documentation/devicetree/bindings/regulator/richtek,rt5033-regulator.yaml