Add hardware monitoring support for the Flex power interface modules PIM4006, PIM4328 and PIM4820. The modules are equipped with dual feed input and has support for hotswap, holdup and various circuit protection functionality. [PATCH 1/5] PIM4328 and PIM4820 use the direct mode data format so a new function is added to the pmbus_core driver to be able to read and decode the COEFFICIENTS command. [PATCH 2/5] The modules have no CAPABILITY or WRITE_PROTECT commands. If these commands are read, the modules return invalid data (0xFF), so in addition to the NO_CAPABILITY flag we need a NO_WRITE_PROTECT flag to tell the pmbus_core driver to not access this register. [PATCH 3/5] The two inputs are modelled using virtual phases but there is a limitation in the pmbus_core that disallows monitoring of phase functions if there is no corresponding function on the page level. In this specific case the PIM4006 module allows monitoring of current on each input separately, but there is no corresponding command on the page level. Is there a specific reason for this limitation? Otherwise we suggest relaxing this criteria. [PATCH 4/5] All modules use manufacturer specific registers (mfr) for status data and only supports the CML bit in the PMBus STATUS register. The driver overrides reading the STATUS register and maps the bits in the mfr registers to the STATUS register alarm bits. Addendum In view of the comment in the generic pmbus driver on adding support for direct mode, we did look into it but decided against it because (1) we do not really have a usecase for it and (2) to implement truly generic direct mode support we need to handle the siuation when there are different coefficients for reading or writing a register. This patch has been tested with PIM4406, PIM4280 and PIM4328 modules. Erik Rosen (5): Add function for reading direct mode coefficients Add new pmbus flag NO_WRITE_PROTECT Allow phase function even if it's not on page Add PMBus driver for PIM4006, PIM4328 and PIM4820 Add documentation for the pim4328 PMBus driver Documentation/hwmon/index.rst | 1 + Documentation/hwmon/pim4328.rst | 105 +++++++++++ MAINTAINERS | 7 + drivers/hwmon/pmbus/Kconfig | 9 + drivers/hwmon/pmbus/Makefile | 1 + drivers/hwmon/pmbus/pim4328.c | 299 +++++++++++++++++++++++++++++++ drivers/hwmon/pmbus/pmbus.h | 4 + drivers/hwmon/pmbus/pmbus_core.c | 63 +++++-- include/linux/pmbus.h | 9 + 9 files changed, 487 insertions(+), 11 deletions(-) create mode 100644 Documentation/hwmon/pim4328.rst create mode 100644 drivers/hwmon/pmbus/pim4328.c base-commit: 6efb943b8616ec53a5e444193dccf1af9ad627b5 -- 2.20.1
