Fix overflows seen when writing into fan speed limit attributes.
Also fix crash due to division by zero, seen when certain very
large values (such as 2147483648, or 0x80000000) are written
into fan speed limit attributes.

Fixes: 594fbe71 ("Add support for GMT G762/G763 PWM fan controllers")
Cc: Arnaud Ebalard <arno@natisbad.org>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Writes into temperature and voltage limit attributes can overflow
due to multiplications with unchecked parameters. Also, the input
parameter to DIV_ROUND_CLOSEST() needis to be range checked.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Writes into temperature limit attributes can overflow due to unbound
values passed to DIV_ROUND_CLOSEST().

Cc: Steve Glendinning <steve.glendinning@shawell.net>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Writes into voltage limit attributes can overflow due to an unbound
multiplication.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Writes into voltage limit attributes can overflow due to an unbound
multiplication.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Fix overflows seen when writing voltage and temperature limit attributes.

The value passed to DIV_ROUND_CLOSEST() needs to be clamped, and the
value parameter passed to nct7802_write_fan_min() is an unsigned long.

Also, writing values larger than 2700000 into a fan limit attribute results
in writing 0 into the chip's limit registers. The exact behavior when
writing this value is unspecified. For consistency, report a limit of
1350000 if the chip register reads 0. This may be wrong, and the chip
behavior should be verified with the actual chip, but it is better than
reporting a value of 0 (which, when written, results in writing a value
of 0x1fff into the chip register).

Fixes: 3434f378 ("hwmon: Driver for Nuvoton NCT7802Y")
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Fix overflows seen when writing large values into various temperature limit
attributes.

The input value passed to DIV_ROUND_CLOSEST() needs to be clamped to avoid
such overflows.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Fix overflows seen when writing large values into temperature limit,
voltage limit, and pwm hysteresis attributes.

The input parameter to DIV_ROUND_CLOSEST() needs to be clamped to avoid
such overflows.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Fix overflows seen when writing large values into voltage limit,
temperature limit, temperature offset, and DAC attributes.

Overflows are seen due to unbound multiplications and additions.

While at it, change the low temperature limit to -128 degrees C,
since this is the minimum temperature accepted by the chip.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Writes into voltage limit attributes can overflow due to an unbound
multiplication.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Install the callbacks via the state machine and let the core invoke the
callbacks on the already online CPUs. When the hotplug state is
unregistered the cleanup function is called for each cpu. So both cpu loops
in init() and exit() are not longer required.

Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-hwmon@vger.kernel.org
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Simple hwmon binding documentation.
Signed-off-by: NJohn Muir <john@jmuir.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Add support for the TI TMP108 temperature sensor with some device
configuration parameters.
Signed-off-by: NJohn Muir <john@jmuir.com>
[groeck: Initialize of_match_table]
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Allocating the sysfs attribute name only if needed and only with the
required minimum length looks optimal, but does not take the additional
overhead for both devm_ data structures and the allocation header itself
into account. This also results in unnecessary memory fragmentation.
Move the sysfs name string into struct hwmon_device_attribute and give it
a sufficient length to reduce this overhead.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The 'groups' parameter of hwmon_device_register_with_info() and
devm_hwmon_device_register_with_info() is only necessary if extra
non-standard attributes need to be provided. Rename the parameter
to extra_groups and clarify the documentation.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

A list of sysfs attribute groups is NULL-terminated, so we always need
to allocate data for at least two groups (the dynamically generated group
plus the NULL pointer). Add a comment to explain the situation.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The is_visible callback provides the sysfs attribute mode and is thus
truly mandatory as documented. Check it once at registration and remove
other checks for its existence.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Inform the user that hwmon_device_register() is deprecated,
and suggest conversion to the newest API. Also remove
hwmon_device_register() from the kernel API documentation.

Note that hwmon_device_register() is not marked as __deprecated()
since doing so might result in build errors.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Describing chip attributes as "attributes which apply to the entire chip"
is confusing. Rephrase to "attributes which are not bound to a specific
input or output".

Also rename hwmon_chip_attr_templates[] to hwmon_chip_attrs[] to indicate
that the respective strings strings are not templates but actual attribute
names.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The new API is so far only suited for data attributes and does not work
well for string attributes, specifically for the 'label' attributes.
Provide a separate callback function for those.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The callback descrption in hwmon.h was misleading and stated that read and
write callbacks would be optional. More accurate is is that the callbacks
are mandatory if readable / writeable attributes are present.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The lm90 driver also supports the Texas Instruments TMP451 sensor chip.
Since the Kconfig description for the driver includes a list of all
compatible chips, mention the TI TMP451 there as well.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Keeping track of the per package platform devices requires an extra object,
which is held in a linked list.

The maximum number of packages is known at init() time. So the extra object
and linked list management can be replaced by an array of platform device
pointers in which the per package devices pointers can be stored. Lookup
becomes a simple array lookup instead of a list walk.

The mutex protecting the list can be removed as well because the array is
only accessed from cpu hotplug callbacks which are already serialized.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The cpu online callback returns success unconditionally even when the
device has no support, micro code mismatches or device allocation fails.
Only if CPU_HOTPLUG is disabled, the init function checks whether the
device list is empty and removes the driver.

This does not make sense. If CPU HOTPLUG is enabled then there is no point
to keep the driver around when it failed to initialize on the already
online cpus. The chance that not yet online CPUs will provide a functional
interface later is very close to zero.

Add proper error return codes, so the setup of the cpu hotplug states fails
when the device cannot be initialized and remove all the magic cruft.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Install the callbacks via the state machine. Setup and teardown are handled
by the hotplug core.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-hwmon@vger.kernel.org
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: rt@linuxtronix.de
Cc: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20161117183541.8588-5-bigeasy@linutronix.deSigned-off-by: NGuenter Roeck <linux@roeck-us.net>

No point in looking up the same thing over and over.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The coretemp driver provides a sysfs interface per physical core. If
hyperthreading is enabled and one of the siblings goes offline the sysfs
interface is removed and then immeditately created again for the
sibling. The only difference of them is the target cpu for the
rdmsr_on_cpu() in the sysfs show functions.

It's way simpler to keep a cpumask of cpus which are active in a package
and only remove the interface when the last sibling goes offline. Otherwise
just move the target cpu for the sysfs show functions to the still online
sibling.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

When a CPU is offlined nothing checks whether it is the target CPU for the
package temperature sysfs interface.

As a consequence all future readouts of the package temperature return
crap:

90000

which is Tjmax of that package.

Check whether the outgoing CPU is the target for the package and assign it
to some other still online CPU in the package. Protect the change against
the rdmsr_on_cpu() in show_crit_alarm().
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Module test reports overflows when writing into temperature and voltage
limit attributes

temp1_min: Suspected overflow: [127000 vs. 0]
temp1_max: Suspected overflow: [127000 vs. 0]
temp1_offset: Suspected overflow: [127000 vs. 0]
temp2_min: Suspected overflow: [127000 vs. 0]
temp2_max: Suspected overflow: [127000 vs. 0]
temp2_offset: Suspected overflow: [127000 vs. 0]
temp3_min: Suspected overflow: [127000 vs. 0]
temp3_max: Suspected overflow: [127000 vs. 0]
temp3_offset: Suspected overflow: [127000 vs. 0]
in0_min: Suspected overflow: [3320 vs. 0]
in0_max: Suspected overflow: [3320 vs. 0]
in4_min: Suspected overflow: [15938 vs. 0]
in4_max: Suspected overflow: [15938 vs. 0]
in6_min: Suspected overflow: [1992 vs. 0]
in6_max: Suspected overflow: [1992 vs. 0]
in7_min: Suspected overflow: [2391 vs. 0]
in7_max: Suspected overflow: [2391 vs. 0]

The problem is caused by conversions from unsigned long to long and
from long to int.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Module test reports:

temp1_max: Suspected overflow: [160000 vs. 0]
temp1_min: Suspected overflow: [160000 vs. 0]

This is seen because the values passed when writing temperature limits
are unbound.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Fixes: 60994698 ("hwmon: Support for Dallas Semiconductor DS620")
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Module test reports:

in0_min: Suspected overflow: [3320 vs. 0]
in0_max: Suspected overflow: [3320 vs. 0]
in4_min: Suspected overflow: [15938 vs. 0]
in4_max: Suspected overflow: [15938 vs. 0]
temp1_max: Suspected overflow: [127000 vs. 0]
temp1_max_hyst: Suspected overflow: [127000 vs. 0]
aout_output: Suspected overflow: [1250 vs. 0]

Code analysis reveals that the overflows are caused by conversions
from unsigned long to long to int, combined with multiplications on
passed values.
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

This is also a preparation for to support more properties like min, max and
alarm.
Signed-off-by: NMichael Walle <michael@walle.cc>
[groeck: Minor alignment changes]
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The check loop for the cpu type is pointless as we already have a cpu model
match before that. The only thing which is not covered by that check would
be a smp system with two different cores. Not likely to happen.

Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Support setting the reference voltage from the device tree.
Signed-off-by: NClemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Replace S_IRUGO with the better readable 0444.
This fixes a checkpatch warning.
Signed-off-by: NClemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Document the devicetree bindings for the Microchip MCP3021/3221.
Signed-off-by: NClemens Gruber <clemens.gruber@pqgruber.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

This is the expected thing for a hwmon driver to do, this changes
the sysfs paths from, say:

  /sys/bus/i2c/devices/0-002c/temp1_input

to:

  /sys/bus/i2c/devices/0-002c/hwmon/hwmon0/temp1_input
Signed-off-by: NJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The adm1278 can optionally monitor the VOUT pin. This functionality is
not enabled at reset, so PMON_CONFIG needs to be modified in order to
enable it.
Signed-off-by: NYi Li <adamliyi@msn.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Add support for the tc654 and tc655 fan controllers from Microchip.

http://ww1.microchip.com/downloads/en/DeviceDoc/20001734C.pdfSigned-off-by: NChris Packham <chris.packham@alliedtelesis.co.nz>
Acked-by: NRob Herring <robh@kernel.org>
[groeck: Fixed continuation line alignments]
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Converts the unsigned temperature values from the i2c read
to be sign extended as defined in the datasheet so that
negative temperatures are properly read.

Fixes: 28e6274d ("hwmon: (amc6821) Avoid forward declaration")
Signed-off-by: NJared Bents <jared.bents@rockwellcollins.com>
Signed-off-by: NMatt Weber <matthew.weber@rockwellcollins.com>
[groeck: Dropped unnecessary continuation line]
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>