| Message ID | 20250124-upstream-lt3074-v1-1-7603f346433e@analog.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add support for LT3074 low voltage linear regulator | expand |
On Fri, Jan 24, 2025 at 11:39:06PM +0800, Cedric Encarnacion wrote: > Add Analog Devices LT3074 Ultralow Noise, High PSRR Dropout Linear > Regulator. Regulator? Then why is it trivial? No enable-gpios? No I2C interface? Best regards, Krzysztof
> -----Original Message----- > From: Krzysztof Kozlowski <krzk@kernel.org> > Sent: Monday, January 27, 2025 3:52 PM > To: Encarnacion, Cedric justine <Cedricjustine.Encarnacion@analog.com> > Cc: Rob Herring <robh@kernel.org>; Krzysztof Kozlowski <krzk+dt@kernel.org>; > Conor Dooley <conor+dt@kernel.org>; Jean Delvare <jdelvare@suse.com>; > Guenter Roeck <linux@roeck-us.net>; Jonathan Corbet <corbet@lwn.net>; > Delphine CC Chiu <Delphine_CC_Chiu@wiwynn.com>; > devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; linux- > hwmon@vger.kernel.org; linux-doc@vger.kernel.org; linux-i2c@vger.kernel.org > Subject: Re: [PATCH 1/2] dt-bindings: trivial-devices: add lt3074 > > [External] > > On Fri, Jan 24, 2025 at 11:39:06PM +0800, Cedric Encarnacion wrote: > > Add Analog Devices LT3074 Ultralow Noise, High PSRR Dropout Linear > > Regulator. > > Regulator? Then why is it trivial? No enable-gpios? No I2C interface? > > Best regards, > Krzysztof I based this driver primarily on the LT7182S dual-channel silent switcher regulator. The LT3074 is a single-channel device with basic enable and power-good GPIOs, fewer registers, and fewer functionalities than the LT7182S. Like other PMBus drivers, its GPIOs are not exposed. Here are other PMBus regulators/power modules found in trivial-devices I also used as reference: - infineon,irps5401 - delta,q54sj108a2 Best regards, Cedric
On 06/02/2025 10:05, Encarnacion, Cedric justine wrote: >> -----Original Message----- >> From: Krzysztof Kozlowski <krzk@kernel.org> >> Sent: Monday, January 27, 2025 3:52 PM >> To: Encarnacion, Cedric justine <Cedricjustine.Encarnacion@analog.com> >> Cc: Rob Herring <robh@kernel.org>; Krzysztof Kozlowski <krzk+dt@kernel.org>; >> Conor Dooley <conor+dt@kernel.org>; Jean Delvare <jdelvare@suse.com>; >> Guenter Roeck <linux@roeck-us.net>; Jonathan Corbet <corbet@lwn.net>; >> Delphine CC Chiu <Delphine_CC_Chiu@wiwynn.com>; >> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; linux- >> hwmon@vger.kernel.org; linux-doc@vger.kernel.org; linux-i2c@vger.kernel.org >> Subject: Re: [PATCH 1/2] dt-bindings: trivial-devices: add lt3074 >> >> [External] >> >> On Fri, Jan 24, 2025 at 11:39:06PM +0800, Cedric Encarnacion wrote: >>> Add Analog Devices LT3074 Ultralow Noise, High PSRR Dropout Linear >>> Regulator. >> >> Regulator? Then why is it trivial? No enable-gpios? No I2C interface? >> >> Best regards, >> Krzysztof > > I based this driver primarily on the LT7182S dual-channel silent switcher > regulator. I do not understand why the base of driver matters here? If it was based on LTFOOBARGROUNDHOG1 would it change something? I know neither LT7182S nor the LTFOOBARGROUNDHOG1. And driver matters here even less - bindings are about hardware, not given implementation in OS. > The LT3074 is a single-channel device with basic enable and > power-good GPIOs, fewer registers, and fewer functionalities than the So it has GPIOs? And by GPIOs you mean what the SoC/CPU, thus the operating system, sees as GPIOs or something else? > LT7182S. Like other PMBus drivers, its GPIOs are not exposed. > > Here are other PMBus regulators/power modules found in trivial-devices > I also used as reference: > > - infineon,irps5401 > - delta,q54sj108a2 I don't know these devices so still no clue. Please rather explain in the terms of the hardware, e.g. what this device has or has not. See also regulator bindings. Best regards, Krzysztof
> On 06/02/2025 10:05, Encarnacion, Cedric justine wrote: > >> -----Original Message----- > >> From: Krzysztof Kozlowski <krzk@kernel.org> > >> Sent: Monday, January 27, 2025 3:52 PM > >> To: Encarnacion, Cedric justine <Cedricjustine.Encarnacion@analog.com> > >> Cc: Rob Herring <robh@kernel.org>; Krzysztof Kozlowski > <krzk+dt@kernel.org>; > >> Conor Dooley <conor+dt@kernel.org>; Jean Delvare > <jdelvare@suse.com>; > >> Guenter Roeck <linux@roeck-us.net>; Jonathan Corbet <corbet@lwn.net>; > >> Delphine CC Chiu <Delphine_CC_Chiu@wiwynn.com>; > >> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; linux- > >> hwmon@vger.kernel.org; linux-doc@vger.kernel.org; linux- > i2c@vger.kernel.org > >> Subject: Re: [PATCH 1/2] dt-bindings: trivial-devices: add lt3074 > >> > >> [External] > >> > >> On Fri, Jan 24, 2025 at 11:39:06PM +0800, Cedric Encarnacion wrote: > >>> Add Analog Devices LT3074 Ultralow Noise, High PSRR Dropout Linear > >>> Regulator. > >> > >> Regulator? Then why is it trivial? No enable-gpios? No I2C interface? > >> > >> Best regards, > >> Krzysztof > > > > I based this driver primarily on the LT7182S dual-channel silent switcher > > regulator. > > > I do not understand why the base of driver matters here? If it was based > on LTFOOBARGROUNDHOG1 would it change something? I know neither > LT7182S > nor the LTFOOBARGROUNDHOG1. And driver matters here even less - > bindings > are about hardware, not given implementation in OS. > > > The LT3074 is a single-channel device with basic enable and > > power-good GPIOs, fewer registers, and fewer functionalities than the > > So it has GPIOs? And by GPIOs you mean what the SoC/CPU, thus the > operating system, sees as GPIOs or something else? Yes, the OS sees these as GPIOs. > > > LT7182S. Like other PMBus drivers, its GPIOs are not exposed. > > > > Here are other PMBus regulators/power modules found in trivial-devices > > I also used as reference: > > > > - infineon,irps5401 > > - delta,q54sj108a2 > > > I don't know these devices so still no clue. Please rather explain in > the terms of the hardware, e.g. what this device has or has not. See > also regulator bindings. The device has enable-gpio and status-gpio. It also has registers of similar functionality which the core driver accesses instead for toggling enable and monitoring status of the device. Upon checking regulator bindings and other related bindings for PMBus devices with regulator support, this indeed should be a separate binding outside of trivial devices. Please let me know what do you suggest. Best Regards, Cedric
On 17/02/2025 10:30, Encarnacion, Cedric justine wrote: >> >>> LT7182S. Like other PMBus drivers, its GPIOs are not exposed. >>> >>> Here are other PMBus regulators/power modules found in trivial-devices >>> I also used as reference: >>> >>> - infineon,irps5401 >>> - delta,q54sj108a2 >> >> >> I don't know these devices so still no clue. Please rather explain in >> the terms of the hardware, e.g. what this device has or has not. See >> also regulator bindings. > > The device has enable-gpio and status-gpio. It also has registers of > similar functionality which the core driver accesses instead for > toggling enable and monitoring status of the device. > > Upon checking regulator bindings and other related bindings for > PMBus devices with regulator support, this indeed should be a > separate binding outside of trivial devices. Please let me know > what do you suggest. Even the GPIOs are outside of trivial devices, so for that sole reason this should not be here but in its own binding. Best regards, Krzysztof
diff --git a/Documentation/devicetree/bindings/trivial-devices.yaml b/Documentation/devicetree/bindings/trivial-devices.yaml index 6bdcd055e763..8f7a8e28fb97 100644 --- a/Documentation/devicetree/bindings/trivial-devices.yaml +++ b/Documentation/devicetree/bindings/trivial-devices.yaml @@ -41,6 +41,8 @@ properties: - adi,ad5110 # Analog Devices ADP5589 Keypad Decoder and I/O Expansion - adi,adp5589 + # Analog Devices LT3074 3A, 5.5V Low Voltage Linear Regulator + - adi,lt3074 # Analog Devices LT7182S Dual Channel 6A, 20V PolyPhase Step-Down Silent Switcher - adi,lt7182s # AMS iAQ-Core VOC Sensor
Add Analog Devices LT3074 Ultralow Noise, High PSRR Dropout Linear Regulator. Signed-off-by: Cedric Encarnacion <cedricjustine.encarnacion@analog.com> --- Documentation/devicetree/bindings/trivial-devices.yaml | 2 ++ 1 file changed, 2 insertions(+)