Documentation/hwmon/pmbus-core.rst

Source file repositories/reference/linux-study-clean/Documentation/hwmon/pmbus-core.rst

File Facts

System
Linux kernel
Corpus path
Documentation/hwmon/pmbus-core.rst
Extension
.rst
Size
15869 bytes
Lines
411
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct pmbus_platform_data {
		u32 flags;              /* Device specific flags */

		/* regulator support */
		int num_regulators;
		struct regulator_init_data *reg_init_data;
	};


Flags
-----

PMBUS_SKIP_STATUS_CHECK

During register detection, skip checking the status register for
communication or command errors.

Some PMBus chips respond with valid data when trying to read an unsupported
register. For such chips, checking the status register is mandatory when
trying to determine if a chip register exists or not.
Other PMBus chips don't support the STATUS_CML register, or report
communication errors for no explicable reason. For such chips, checking the
status register must be disabled.

Some i2c controllers do not support single-byte commands (write commands with
no data, i2c_smbus_write_byte()). With such controllers, clearing the status
register is impossible, and the PMBUS_SKIP_STATUS_CHECK flag must be set.

PMBUS_WRITE_PROTECTED

Set if the chip is write protected and write protection is not determined
by the standard WRITE_PROTECT command.

PMBUS_NO_CAPABILITY

Some PMBus chips don't respond with valid data when reading the CAPABILITY
register. For such chips, this flag should be set so that the PMBus core
driver doesn't use CAPABILITY to determine its behavior.

PMBUS_READ_STATUS_AFTER_FAILED_CHECK

Read the STATUS register after each failed register check.

Some PMBus chips end up in an undefined state when trying to read an
unsupported register. For such chips, it is necessary to reset the
chip pmbus controller to a known state after a failed register check.
This can be done by reading a known register. By setting this flag the
driver will try to read the STATUS register after each failed
register check. This read may fail, but it will put the chip into a
known state.

PMBUS_NO_WRITE_PROTECT

Some PMBus chips respond with invalid data when reading the WRITE_PROTECT
register. For such chips, this flag should be set so that the PMBus core
driver doesn't use the WRITE_PROTECT command to determine its behavior.

PMBUS_USE_COEFFICIENTS_CMD

When this flag is set the PMBus core driver will use the COEFFICIENTS
register to initialize the coefficients for the direct mode format.

PMBUS_OP_PROTECTED

Set if the chip OPERATION command is protected and protection is not
determined by the standard WRITE_PROTECT command.

PMBUS_VOUT_PROTECTED

Set if the chip VOUT_COMMAND command is protected and protection is not

Annotation

Implementation Notes