drivers: power: ltm4700: Add support for LTM4700 dual-channel PMBus regulator

doc/sphinx/source/drivers/power/ltm4700.rst

@@ -0,0 +1 @@
+.. include:: ../../../../../drivers/power/ltm4700/README.rst

doc/sphinx/source/projects/power/ltm4700.rst

@@ -0,0 +1 @@
+.. include:: ../../../../../projects/ltm4700/README.rst

drivers/power/CMakeLists.txt

@@ -82,6 +82,11 @@ no_os_sources_ifdef(CONFIG_POWER_LTM4686 ${CMAKE_CURRENT_SOURCE_DIR}/ltm4686/ltm
 no_os_sources_ifdef(CONFIG_POWER_IIO_LTM4686 ${CMAKE_CURRENT_SOURCE_DIR}/ltm4686/iio_ltm4686.c)
 target_include_directories(no-os PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/ltm4686)
 
+# ltm4700
+no_os_sources_ifdef(CONFIG_POWER_LTM4700 ${CMAKE_CURRENT_SOURCE_DIR}/ltm4700/ltm4700.c)
+no_os_sources_ifdef(CONFIG_POWER_IIO_LTM4700 ${CMAKE_CURRENT_SOURCE_DIR}/ltm4700/iio_ltm4700.c)
+target_include_directories(no-os PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/ltm4700)
+
 # ltp8800
 no_os_sources_ifdef(CONFIG_POWER_LTP8800 ${CMAKE_CURRENT_SOURCE_DIR}/ltp8800/ltp8800.c)
 no_os_sources_ifdef(CONFIG_POWER_IIO_LTP8800 ${CMAKE_CURRENT_SOURCE_DIR}/ltp8800/iio_ltp8800.c)

drivers/power/Kconfig

@@ -166,6 +166,16 @@ config POWER_IIO_LTM4686
 	bool "Enable LTM4686 IIO driver"
 	default n
 
+config POWER_LTM4700
+	depends on I2C
+	bool "Enable LTM4700 power driver"
+	default n
+
+config POWER_IIO_LTM4700
+	select POWER_LTM4700
+	bool "Enable LTM4700 IIO driver"
+	default n
+
 config POWER_LTP8800
 	depends on I2C
 	bool "Enable LTP8800 power driver"

drivers/power/ltm4700/README.rst

@@ -0,0 +1,238 @@
+LTM4700 no-OS Driver
+====================
+
+Supported Devices
+-----------------
+
+* `LTM4700 <https://www.analog.com/LTM4700>`_
+
+Overview
+--------
+
+The LTM4700 is a dual 50A or single 100A step-down µModule regulator featuring
+remote configurability and telemetry-monitoring of power management parameters
+over PMBus—an open standard I2C-based digital interface protocol.
+
+The LTM4700 is comprised of fast analog control loops, precision mixed-signal
+circuitry, EEPROM, power MOSFETs, inductors and supporting components.
+
+Key Features
+------------
+
+* Dual 50A or Single 100A Digitally Adjustable Outputs
+* Wide Input Voltage: 4.5V to 16V
+* Output Voltage Range: 0.5V to 1.8V
+* ±0.5% Maximum DC Output Error Over Temperature
+* ±3% Current Readback Accuracy (25°C to 125°C)
+* 400kHz PMBus-Compliant I2C Serial Interface
+* Integrated 16-Bit ∆Σ ADC for telemetry
+* Constant Frequency Current Mode Control
+* Internal EEPROM with Fault Logging and ECC
+
+Supported Features
+------------------
+
+* Device identification
+* Dual-channel voltage and current monitoring
+* LINEAR11/LINEAR16 data format conversion
+* Comprehensive status monitoring
+* PMBus command interface
+* NVM operations for configuration storage
+* Peak value tracking
+* IIO framework integration
+
+Communication Interface
+-----------------------
+
+The device uses PMBus 1.3 compliant I2C interface:
+
+* **Bus Speed**: Up to 400kHz
+* **Default Address**: 0x5A (7-bit)
+* **Data Formats**: LINEAR11, LINEAR16
+* **CRC Support**: Optional polynomial 0x7
+
+Device Variants
+---------------
+
++----------+----------------+-------------------------------------------+
+| Device   | Special ID     | Description                               |
++==========+================+===========================================+
+| LTM4700  | 0x4130         | Dual 50A or Single 100A µModule           |
++----------+----------------+-------------------------------------------+
+
+PMBus Commands
+--------------
+
+The driver supports standard PMBus commands and manufacturer-specific commands:
+
+**Standard Commands:**
+  - PAGE, OPERATION, CLEAR_FAULTS
+  - VOUT_COMMAND, VOUT_MAX, VOUT_MARGIN_HIGH/LOW
+  - STATUS_BYTE, STATUS_WORD, STATUS_VOUT, STATUS_IOUT
+  - READ_VIN, READ_IIN, READ_VOUT, READ_IOUT
+  - READ_TEMPERATURE_1/2, READ_POUT, READ_PIN
+
+**Manufacturer Commands:**
+  - MFR_SPECIAL_ID (device identification)
+  - MFR_VOUT_PEAK, MFR_IOUT_PEAK, MFR_VIN_PEAK
+  - MFR_CLEAR_PEAKS, MFR_ADC_CONTROL
+  - MFR_PWM_MODE, MFR_PWM_COMP
+  - Store/restore user settings
+
+Data Formats
+------------
+
+**LINEAR11 Format:**
+  - 5-bit signed exponent + 11-bit signed mantissa
+  - Used for: current, power, temperature, time values
+
+**LINEAR16 Format:**
+  - Fixed exponent (-12) + 16-bit mantissa
+  - Used for: voltage values (VOUT_COMMAND, READ_VOUT)
+
+Channel Configuration
+---------------------
+
+The LTM4700 supports dual-channel operation:
+
+* **Channel 0**: VOUT0, IOUT0, POUT0
+* **Channel 1**: VOUT1, IOUT1, POUT1
+* **Global**: VIN, IIN, PIN, temperatures
+
+Pages are used to select channels for PMBus commands.
+
+IIO Integration
+---------------
+
+The driver provides comprehensive IIO (Industrial I/O) support:
+
+**IIO Channels:**
+  - ``vin``: Input voltage monitoring
+  - ``vout0/vout1``: Output voltage monitoring and control
+  - ``iin``: Input current monitoring
+  - ``iout0/iout1``: Output current monitoring
+  - ``pin``: Input power monitoring
+  - ``pout0/pout1``: Output power monitoring
+  - ``temp0/temp1``: Temperature monitoring
+  - ``frequency0/frequency1``: Switching frequency
+
+**IIO Attributes:**
+  - ``raw``: Read telemetry values
+  - ``command``: Set output voltage
+  - ``operation``: Control channel operation mode
+  - ``clear_peaks``: Reset peak value tracking
+  - ``device_id``: Device variant identification
+
+Usage Example
+-------------
+
+Basic device initialization:
+
+.. code-block:: c
+
+    struct ltm4700_init_param init_param = {
+        .i2c_init = &i2c_init_param,
+        .crc_en = false
+    };
+
+    struct ltm4700_dev *dev;
+    int ret = ltm4700_init(&dev, &init_param);
+
+Reading telemetry:
+
+.. code-block:: c
+
+    int vin_mv, vout0_mv, iout0_ma;
+
+    // Read input voltage in millivolts
+    ltm4700_read_value(dev, 0, LTM4700_VIN, &vin_mv);
+
+    // Read output voltage for channel 0
+    ltm4700_read_value(dev, 0, LTM4700_VOUT, &vout0_mv);
+
+    // Read output current for channel 0
+    ltm4700_read_value(dev, 0, LTM4700_IOUT, &iout0_ma);
+
+Setting output voltage:
+
+.. code-block:: c
+
+    // Set VOUT0 to 1.2V (1200mV)
+    ltm4700_vout_value(dev, 0, 1200000, 1800000); // command, max
+
+    // Set operation mode
+    ltm4700_set_operation(dev, 0, LTM4700_OPERATION_ON);
+
+IIO Usage:
+
+.. code-block:: c
+
+    struct ltm4700_iio_desc *iio_desc;
+    struct ltm4700_iio_desc_init_param iio_init_param = {
+        .ltm4700_init_param = &ltm4700_init_param
+    };
+
+    ltm4700_iio_init(&iio_desc, &iio_init_param);
+
+Status monitoring:
+
+.. code-block:: c
+
+    struct ltm4700_status status;
+    ltm4700_read_status(dev, 0, LTM4700_STATUS_ALL_TYPE, &status);
+
+    if (status.vout & VOUT_OV_FAULT)
+        printf("Output overvoltage fault detected\n");
+
+Design Considerations
+---------------------
+
+**Power Supply Design:**
+  - Provide adequate input capacitance for transient response
+  - Follow recommended PCB layout guidelines
+  - Consider thermal management for high current operation
+
+**I2C Interface:**
+  - Use appropriate pull-up resistors (1kΩ - 10kΩ)
+  - Keep trace lengths short for high-speed operation
+  - Consider CRC protection for noisy environments
+
+**Dual Channel Operation:**
+  - Channels can operate independently or in current sharing mode
+  - Use PAGE command to select channel for configuration
+  - Monitor both channels for fault conditions
+
+**Fault Management:**
+  - Implement appropriate fault handling in application
+  - Use status registers to identify fault conditions
+  - Consider automated recovery strategies
+
+Build Configuration
+-------------------
+
+Add the LTM4700 driver to your project by including in ``src.mk``:
+
+.. code-block:: make
+
+    SRCS += $(DRIVERS)/power/ltm4700/ltm4700.c
+
+For IIO support, also include:
+
+.. code-block:: make
+
+    SRCS += $(DRIVERS)/power/ltm4700/iio_ltm4700.c \
+            $(LIBRARIES)/iio/iio.c
+
+Dependencies:
+  - I2C platform driver
+  - no-OS utility functions
+  - CRC8 library (if CRC enabled)
+  - IIO framework (for IIO support)
+
+Links
+-----
+
+* `LTM4700 Product Page <https://www.analog.com/LTM4700>`_
+* `LTM4700 Datasheet <https://www.analog.com/media/en/technical-documentation/data-sheets/ltm4700.pdf>`_
+* `PMBus Specification <https://pmbus.org/specification/>`_
+* `no-OS Framework <https://github.com/analogdevicesinc/no-OS>`_