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Diffstat (limited to 'Documentation/hwmon/pmbus-core.rst')
-rw-r--r-- | Documentation/hwmon/pmbus-core.rst | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/Documentation/hwmon/pmbus-core.rst b/Documentation/hwmon/pmbus-core.rst index 1eaf2b015837..fdfb23773148 100644 --- a/Documentation/hwmon/pmbus-core.rst +++ b/Documentation/hwmon/pmbus-core.rst @@ -308,6 +308,14 @@ currently provides a flags field with four bits used:: #define PMBUS_READ_STATUS_AFTER_FAILED_CHECK BIT(3) + #define PMBUS_NO_WRITE_PROTECT BIT(4) + + #define PMBUS_USE_COEFFICIENTS_CMD BIT(5) + + #define PMBUS_OP_PROTECTED BIT(6) + + #define PMBUS_VOUT_PROTECTED BIT(7) + struct pmbus_platform_data { u32 flags; /* Device specific flags */ @@ -358,3 +366,45 @@ 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 +determined by the standard WRITE_PROTECT command. + +Module parameter +---------------- + +pmbus_core.wp: PMBus write protect forced mode + +PMBus may come up with a variety of write protection configuration. +'pmbus_core.wp' may be used if a particular write protection is necessary. +The ability to actually alter the protection may also depend on the chip +so the actual runtime write protection configuration may differ from +the requested one. pmbus_core currently support the following value: + +* 0: write protection removed. +* 1: Disable all writes except to the WRITE_PROTECT, OPERATION, + PAGE, ON_OFF_CONFIG and VOUT_COMMAND commands. +* 2: Disable all writes except to the WRITE_PROTECT, OPERATION and + PAGE commands. +* 3: Disable all writes except to the WRITE_PROTECT command. Note that + protection should include the PAGE register. This may be problematic + for multi-page chips, if the chips strictly follows the PMBus + specification, preventing the chip from changing the active page. |