The ADT7473 and ADT7475 support bypassing voltage input attenuators on voltage input 1 and the ADT7476 and ADT7490 additionally support bypassing voltage input attenuators on voltage inputs 0, 3, and 4. This can be useful to improve measurement resolution when measuring voltages 0 V - 2.25 V. This patch adds 4 optional devicetree properties to the adt7475 driver, each setting the attenuator bypass (or clearing) on a specific voltage input. * v6 - removed unnecessary comments marked for kernal documentation in file adt7475.c. - fixed parenthesis whitespace allignment in multiple places in file adt7475.c. - removed unnecessary parentheses around data->config4 in file adt7475.c. - removed unused assignment "int i = 0" in file adt7475.c. - fixed mispelling of documentation in commit subject. * v5 - modified adt7475.yaml to remove dt_binding_check errors - made various alignment fixes to adt7475.c to improve style. - renamed function modify_config_from_dts_prop to modify_config - changed return type of function modify_config to void - function modify_config error return code modified no longer override the dependent functions i2c_smbus_write_byte_data error. - renamed function load_all_bypass_attenuators to load_attenuators - in function load_attenuators the two local variables config2_copy and config4_copy have been combined into one: conf_copy. * v4 - fixed a small error in file adt7475.yaml (duplicate property names). * v3 - removed the functionality to set the global attenuator bypass. - added functionality to allow bypassing voltage input 1 on the ADT7473 and ADT7475. - added DTS definition file adt7475.yaml and 4 new properties. - added the previousely missing newline character to the end of file adt7475.c. * v2 - removed sysfs changes from patch - removed adt7475_write macro from patch and replaced it by using the i2c_smbus_write_byte_data function directly in code. - removed config4_attenuate_index function from patch and replaced it by modifying the function load_individual_bypass_attenuators to use hard coded bit values. - modified function load_individual_bypass_attenuators to use 4 if statements, one for each voltage input, replacing the for loop. - modified function adt7475_probe to check the device is a ADT7476 or ADT7490 (other devices do not support bypassing all or individual attenuators), and only then set the relevant bits. - added new file adt7475.txt to document the new devicetree properties. - removed c++ style comments. Logan Shaw (2): hwmon: (adt7475) Added attenuator bypass support dt-bindings: hwmon: (adt7475) Added missing adt7475 documentation .../devicetree/bindings/hwmon/adt7475.yaml | 95 +++++++++++++++++++ drivers/hwmon/adt7475.c | 55 +++++++++++ 2 files changed, 150 insertions(+) create mode 100644 Documentation/devicetree/bindings/hwmon/adt7475.yaml -- 2.25.0
