Version 2 of the PSU supports a second page of data and changes the
format of the FW version. Use the devicetree binding to differentiate
between the version the driver should use.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/1567192263-15065-4-git-send-email-eajames@linux.ibm.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add the driver to monitor Inspur Power System power supplies
with hwmon over pmbus.
This driver adds sysfs attributes for additional power supply data,
including vendor, model, part_number, serial number,
firmware revision, hardware revision, and psu mode(active/standby).
Signed-off-by: John Wang <wangzqbj@inspur.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20190819091509.29276-1-wangzqbj@inspur.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
There is a typo in MAX37185_NUM_FAN_PAGES. To be consistent, it should be
MAX31785_NUM_FAN_PAGES (1 and 7 switched).
At line 24, we already have:
#define MAX31785_NR_FAN_PAGES 6
and MAX37185_NUM_FAN_PAGES seems to be unused.
It is likely that it is only a typo and/or a left-over.
So, axe it.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20190721101553.20911-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Build bot reports the following build issue after commit 9091373ab7
("gpio: remove less important #ifdef around declarations):
In file included from drivers/hwmon/pmbus/ucd9000.c:19:0:
>> include/linux/gpio/driver.h:576:1: error: redefinition of 'gpiochip_add_pin_range'
gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
^~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/hwmon/pmbus/ucd9000.c:18:0:
include/linux/gpio.h:245:1: note: previous definition of 'gpiochip_add_pin_range' was here
gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
^~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/hwmon/pmbus/ucd9000.c:19:0:
>> include/linux/gpio/driver.h:583:1: error: redefinition of 'gpiochip_add_pingroup_range'
gpiochip_add_pingroup_range(struct gpio_chip *chip,
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/hwmon/pmbus/ucd9000.c:18:0:
include/linux/gpio.h:254:1: note: previous definition of 'gpiochip_add_pingroup_range' was here
gpiochip_add_pingroup_range(struct gpio_chip *chip,
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/hwmon/pmbus/ucd9000.c:19:0:
>> include/linux/gpio/driver.h:591:1: error: redefinition of 'gpiochip_remove_pin_ranges'
gpiochip_remove_pin_ranges(struct gpio_chip *chip)
^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/hwmon/pmbus/ucd9000.c:18:0:
include/linux/gpio.h:263:1: note: previous definition of 'gpiochip_remove_pin_ranges' was here
gpiochip_remove_pin_ranges(struct gpio_chip *chip)
This is caused by conflicting defines from linux/gpio.h and
linux/gpio/driver.h. Drivers should not include both the legacy and
the new API headers. This driver doesn't even use linux/gpio.h so
remove it.
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20190808080144.6183-1-brgl@bgdev.pl
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Not every chip supported by this driver supports setting the number
of samples for power averaging. Also, the power monitoring register
is not always a 16-bit register, and the configuration bits used for
voltage sampling are different depending on the register width.
Some conditional code is needed to fix the problem.
On top of all that, the compiler complains about problems with
FIELD_GET and FIELD_PREP macros if the file is built with W=1.
Avoid using those macros to silence the warning.
Cc: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Reviewed-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add a driver to support the Infineon IRPS5401 PMIC. This chip has 5
pages corresponding to 4 switching outputs and one linear (LDO) output.
The switching and LDO outputs have slightly different supported
parameters.
Signed-off-by: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Added pmbus driver for the new device Infineon pxe1610
voltage regulator. It also supports similar family device
PXE1110 and PXM1310.
Signed-off-by: Vijay Khemka <vijaykhemka@fb.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The device supports setting the number of samples for averaging the
measurements. There are two separate settings - PWR_AVG for averaging
PIN and VI_AVG for averaging VIN/VAUX/IOUT, both being part of
PMON_CONFIG register. The values are stored as exponent of base 2 of the
actual number of samples that will be taken.
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
[groeck: Dropped unused variables]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Some chips have attributes which exist on more than one page but the
attribute is not presently marked as paged. This causes the attributes
to be generated with the same label, which makes it impossible for
userspace to tell them apart.
Marking all such attributes as paged would result in the page suffix
being added regardless of whether they were present on more than one
page or not, which might break existing setups. Therefore, we add a
second check which treats the attribute as paged, even if not marked as
such, if it is present on multiple pages.
Fixes: b4ce237b7f ("hwmon: (pmbus) Introduce infrastructure to detect sensors and limit registers")
Signed-off-by: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
update_lock is a mutex intended to protect write operations. It was not
taken, however, when _pmbus_write_word_data is called from
pmbus_set_samples() function which may cause problems especially when
some PMBUS_VIRT_* operation is implemented as a read-modify-write cycle.
This patch makes sure the lock is held during the operation.
Fixes: 49c4455dcc ("hwmon: (pmbus) Introduce PMBUS_VIRT_*_SAMPLES registers")
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
[groeck: Declared and initialized missing 'data' variable]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Based on 3 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1105 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
675 mass ave cambridge ma 02139 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 441 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Intersil ISL68137 is a digital output 7-phase configurable PWM
controller with an AVSBus interface.
Signed-off-by: Maxim Sloyko <maxims@google.com>
Signed-off-by: Robert Lippert <rlippert@google.com>
Signed-off-by: Patrick Venture <venture@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch makes it possible to pass custom struct attribute_group array
via the pmbus_driver_info struct so that those can be added to the
attribute groups passed to hwmon_device_register_with_groups().
This makes it possible to register custom sysfs attributes by PMBUS
drivers similar to how you can do this with most other busses/classes.
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Manufacturer specific SAMPLES_FOR_AVG register allows setting the number
of samples used in computing the average values (PMBUS_VIRT_READ_*_AVG).
The number we write is an exponent of base 2 of the number of samples so
for example writing 3 will result in 8 samples average.
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Those virtual registers can be used to export manufacturer specific
functionality for controlling the number of samples for average values
reported by the device.
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Replace S_<PERMS> with octal values.
The conversion was done automatically with coccinelle. The semantic patches
and the scripts used to generate this commit log are available at
https://github.com/groeck/coccinelle-patches/.
This patch does not introduce functional changes. It was verified by
compiling the old and new files and comparing text and data sizes.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add the pmbus driver for the Infineon ir38064 voltage regulator.
VOUT_MODE is not supported by the device. The driver fakes linear16
mode with exponent value -8.
The device supports VOUT_PEAK, IOUT_PEAK, and TEMPERATURE_PEAK, however
this driver does not enable them.
Signed-off-by: Maxim Sloyko <maxims@google.com>
Signed-off-by: Patrick Venture <venture@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
If CONFIG_OF is not enabled, the following build warning is observed.
drivers/hwmon/pmbus/ucd9000.c:154:34: warning:
‘ucd9000_of_match’ defined but not used
Mark ucd9000_of_match as __maybe_unused to fix the problem.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
If CONFIG_OF is not enabled, the following build warning is observed.
drivers/hwmon/pmbus/tps53679.c💯34: warning:
‘tps53679_of_match’ defined but not used
Marking tps53679_of_match as __maybe_unused fixes the problem.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
If CONFIG_OF is not enabled, the following build warning is
observed.
drivers/hwmon/pmbus/ucd9200.c:50:34: warning:
‘ucd9200_of_match’ defined but not used
Mark it as __maybe_unused to fix the problem.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Provide support for PSU DPS-650AB from Delta Electronics, INC.
Signed-off-by: Xiaoting Liu <xiaoting.liu@hxt-semitech.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Current code compares device name with name in i2c_device_id to decide
whether PMBUS_SKIP_STATUS_CHECK should be set in pmbus_platform_data,
which makes adding new devices with PMBUS_SKIP_STATUS_CHECK should also
modify code in pmbus_probe().
This patch adds pmbus_device_info to save pages and flags. Its pointer
is put in driver_data of i2c_device_id, which makes adding new device
more straightforward.
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Xiaoting Liu <xiaoting.liu@hxt-semitech.com>
[groeck: Use designated structure initializers to improve readability]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Fix tps53679_probe() by using dynamically allocated "pmbus_driver_info"
structure instead of static. Usage of static structures causes
overwritten of the field "vrm_version", in case the system is equipped
with several tps53679 devices with the different "vrm_version".
In such case the last probed device overwrites this field for all
others.
Fixes: 610526527a ("hwmon: (pmbus) Add support for Texas Instruments tps53679 device")
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
There is a spelling mistake in the module description text, fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The ADM series of hotswap controllers support extending
the current measurement range by using a sensing resistor
value other than the typical 1 mOhm. For example, using a 0.5 mOhm
sensing resistor doubles the maximal current can be measured.
Current driver assumes a shunt resistor value of 1 mOhm in calculation,
meaning for other resistor values, hwmon will report scaled
current/power measurements. This patch parses device tree parameter
"shunt-resistor-micro-ohms", if there is one.
Signed-off-by: Kun Yi <kunyi@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Devices with compatible="pmbus" field have zero initial page count,
and pmbus_clear_faults() being called before the page count auto-
detection does not actually clear faults because it depends on the
page count. Non-cleared faults in its turn may fail the subsequent
page count auto-detection.
This patch fixes this problem by calling pmbus_clear_fault_page()
for currently set page and calling pmbus_clear_faults() after the
page count was detected.
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Bazhenov <bazhenov.dn@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.
Also since commit f467c5640c ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:
...
One side effect of (and the main motivation for) this change is making
the following two definitions behave exactly the same:
config FOO
bool
config FOO
bool
default n
With this change, neither of these will generate a
'# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
That might make it clearer to people that a bare 'default n' is
redundant.
...
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch adds support for LTM4686 Ultrathin Dual 10A or
Single 20A uModule Regulator with Digital Power System Management.
Datasheet: http://www.analog.com/ltm4686
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
MAX34451 is a 16-Channel Voltage/Current Monitor and 12-Channel
Sequencer.
Signed-off-by: Kun Yi <kunyi@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Expose the gpiN_fault fields of mfr_status as individual debugfs
attributes. This provides a way for users to be easily notified of gpi
faults. Also provide the whole mfr_status register in debugfs.
Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add a struct gpio_chip and define some methods so that this device's
I/O can be accessed via /sys/class/gpio.
Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
A negative page register value means that no page needs to be
selected. This is used by status register read operations and needs
to be accepted. The failure to do so so results in missed status
and limit registers.
Fixes: da8e48ab48 ("hwmon: (pmbus) Always call _pmbus_read_byte in core driver")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
A negative page register value means that no page needs to be
selected. This is used by status register evaluations and needs
to be accepted.
Fixes: da8e48ab48 ("hwmon: (pmbus) Always call _pmbus_read_byte in core driver")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The ir35221 datasheet describes specific scaling factors for a number of
commands which the current driver applies when reading.
However now that the ir35221 has been tested on machines with more
easily verifiable readings these descriptions have turned out to be
superfluous and reading each command according to the linear format is
sufficient.
Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Building without CONFIG_LEDS_CLASS causes a link failure:
drivers/hwmon/pmbus/ibm-cffps.o: In function `ibm_cffps_probe':
ibm-cffps.c:(.text+0x4f4): undefined reference to `devm_of_led_classdev_register'
This adds the required dependency.
Fixes: ef9e1cdf41 ("hwmon: (pmbus/cffps) Add led class device ...")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This power supply device doesn't correctly manage it's own fault led.
Add an led class device and register it so that userspace can manage
power supply fault led as necessary.
Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This power supply device regularly fails to read VOUT_MODE due to the
CML bit going high. This results in an incorrect exponent used for the
voltage data, and therefore the power supply reports incorrect voltage.
Work around this by setting the pmbus flag to skip the CML check.
Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Fixes: f69316d62c ("hwmon: (pmbus) Add IBM Common Form Factor (CFF) ...")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add debugfs entries for additional power supply data, including part
number, serial number, FRU number, firmware revision, ccin, and the
input history of the power supply. The input history is 10 minutes of
input power data in the form of twenty 30-second packets. Each packet
contains average and maximum power for that 30 second period.
Signed-off-by: Edward A. James <eajames@us.ibm.com>
[groeck: Fixed endianness problem]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Pmbus client drivers, if they want to use debugfs, should use the same
root directory as the pmbus debugfs entries are using. Therefore, export
the device dentry for the pmbus client.
Signed-off-by: Edward A. James <eajames@us.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The driver doesn't have a struct of_device_id table but supported devices
are registered via Device Trees. This is working on the assumption that a
I2C device registered via OF will always match a legacy I2C device ID and
that the MODALIAS reported will always be of the form i2c:<device>.
But this could change in the future so the correct approach is to have an
OF device ID table if the devices are registered via OF.
Before this patch:
$ modinfo drivers/hwmon/pmbus/max31785.ko | grep alias
alias: i2c:max31785a
alias: i2c:max31785
After this patch:
$ modinfo drivers/hwmon/pmbus/max31785.ko | grep alias
alias: i2c:max31785a
alias: i2c:max31785
alias: of:N*T*Cmaxim,max31785aC*
alias: of:N*T*Cmaxim,max31785a
alias: of:N*T*Cmaxim,max31785C*
alias: of:N*T*Cmaxim,max31785
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The dual tachometer feature is implemented in hardware with a TACHSEL
input to indicate the rotor under measurement, and exposed on the device
by extending the READ_FAN_SPEED_1 word with two extra bytes*. The need
to read the non-standard four-byte response leads to a cut-down
implementation of i2c_smbus_xfer_emulated() included in the driver.
Further, to expose the second rotor tachometer value to userspace the
values are exposed through virtual pages. We re-route accesses to
FAN_CONFIG_1_2 and READ_FAN_SPEED_1 on pages 23-28 (not defined by the
hardware) to the same registers on pages 0-5, and with the latter command
we extract the value from the second word of the four-byte response.
* The documentation recommends the slower rotor be associated with
TACHSEL=0, which corresponds to the first word of the response. The
TACHSEL=0 measurement is used by the controller's closed-loop fan
management to judge target fan rate.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Some circumstances call for virtual pages, to expose multiple values
packed into an extended PMBus register in a manner non-compliant with
the PMBus standard. An example of this is the Maxim MAX31785 controller,
which extends the READ_FAN_SPEED_1 PMBus register from two to four bytes
to support tach readings for both rotors of a dual rotor fan. This extended
register contains two word-sized values, one reporting the rate of the
fastest rotor, the other the rate of the slowest. The concept of virtual
pages aids this situation by mapping the page number onto the value to be
selected from the vectored result.
We should not try to set virtual pages on the device as such a page
explicitly doesn't exist; add a flag so we can avoid doing so.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The implementation makes use of the new fan control virtual registers
exposed by the pmbus core. It mixes use of the default implementations
with some overrides via the read/write handlers to handle FAN_COMMAND_1
on the MAX31785, whose definition breaks the value range into various
control bands dependent on RPM or PWM mode.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Expose fanX_target, pwmX and pwmX_enable hwmon sysfs attributes.
Fans in a PMBus device are driven by the configuration of two registers,
FAN_CONFIG_x_y and FAN_COMMAND_x: FAN_CONFIG_x_y dictates how the fan
and the tacho operate (if installed), while FAN_COMMAND_x sets the
desired fan rate. The unit of FAN_COMMAND_x is dependent on the
operational fan mode, RPM or PWM percent duty, as determined by the
corresponding configuration in FAN_CONFIG_x_y.
The mapping of fanX_target, pwmX and pwmX_enable onto FAN_CONFIG_x_y and
FAN_COMMAND_x is implemented with the addition of virtual registers to
facilitate the necessary side-effects of each access:
1. PMBUS_VIRT_FAN_TARGET_x
2. PMBUS_VIRT_PWM_x
3. PMBUS_VIRT_PWM_ENABLE_x
Some complexity arises with the fanX_target and pwmX attributes both mapping
onto FAN_COMMAND_x: There is no general mapping between PWM percent duty and
RPM, so we can't display values in either attribute in terms of the other
(which in my mind is the intuitive, if impossible, behaviour). This problem
also affects the pwmX_enable attribute which allows userspace to switch between
full speed, manual PWM and a number of automatic control modes, possibly
including a switch to RPM behaviour (e.g. automatically adjusting PWM duty to
reach a RPM target, the behaviour of fanX_target).
The next most intuitive behaviour is for fanX_target and pwmX to simply be
independent, to retain their most recently set value even if that value is not
active on the hardware (due to switching to the alternative control mode). This
property of retaining the value independent of the hardware state has useful
results for both userspace and the kernel: Userspace always sees a sensible
value in the attribute (the last thing it was set to, as opposed to 0 or
receiving an error on read), and the kernel can use the attributes as a value
cache. This latter point eases the implementation of pwmX_enable, which can
look up the associated pmbus_sensor object, take its cached value and apply it
to hardware on changing control mode. This ensures we will not arbitrarily set
a PWM value as an RPM value or vice versa, and we can assume that the RPM or
PWM value set was sensible at least at some point in the past.
Finally, the DIRECT mode coefficients of some controllers is different between
RPM and PWM percent duty control modes, so PSC_PWM is introduced to capture the
necessary coefficients. As pmbus core had no PWM support previously PSC_FAN
continues to be used to capture the RPM DIRECT coefficients, but in order to
avoid falsely applying RPM scaling to PWM values I have introduced the
PMBUS_HAVE_PWM12 and PMB_BUS_HAVE_PWM34 feature bits. These feature bits allow
drivers to explicitly declare PWM support in order to have the attributes
exposed.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
