Commit graph

164 commits

Author SHA1 Message Date
Dmitry Bazhenov e7c6a55606 hwmon: (pmbus) Fix page count auto-detection.
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>
2018-10-15 12:44:36 -07:00
Bartlomiej Zolnierkiewicz 04e79eb704 hwmon: (pmbus) remove redundant 'default n' from Kconfig
'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>
2018-10-11 20:08:16 -07:00
Michael Hennerich 4e15d05d9c drivers: hwmon: (pmbus/ltc2978) Add support for LTM4686 uModule
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>
2018-10-10 20:37:13 -07:00
Kun Yi 7a001dbab4 hwmon: (pmbus/max34440) Add support for MAX34451.
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>
2018-07-08 20:08:13 -07:00
Kees Cook a86854d0c5 treewide: devm_kzalloc() -> devm_kcalloc()
The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

        devm_kzalloc(handle, a * b, gfp)

with:
        devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

        devm_kzalloc(handle, a * b * c, gfp)

with:

        devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
  devm_kzalloc(HANDLE,
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  devm_kzalloc(HANDLE,
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
  devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * E2
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Guenter Roeck 4ff0ce227a hwmon: (pmbus/adm1275) Add support for ADM1272
The chip is quite similar to other chips in the series,
but as usual it comes with its own quirks.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2018-03-22 09:32:17 -07:00
Christopher Bostic 72816cb06e hwmon: (ucd9000) Add debugfs attributes to provide mfr_status
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>
2018-03-16 18:52:35 -07:00
Christopher Bostic ca781fb7fd hwmon: (ucd9000) Add gpio chip interface
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>
2018-03-16 18:52:04 -07:00
Guenter Roeck ecb29abd4c hwmon: (pmbus/adm1275) Accept negative page register values
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>
2018-03-10 18:59:56 -08:00
Guenter Roeck a46f8cd696 hwmon: (pmbus/max8688) Accept negative page register values
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>
2018-03-10 18:59:47 -08:00
Samuel Mendoza-Jonas 08f411bcb5 hwmon: (pmbus/ir35221) Remove unnecessary scaling
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>
2018-01-15 04:22:46 -08:00
Arnd Bergmann b007640649 hwmon: (pmbus/ibm-cffps) Add dependency on LEDS_CLASS
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>
2018-01-12 09:24:16 -08:00
eajames@linux.vnet.ibm.com ef9e1cdf41 hwmon: (pmbus/cffps) Add led class device for power supply fault led
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>
2018-01-11 10:28:35 -08:00
Eddie James 4471879acf hwmon: (pmbus) cffps: Add PMBUS_SKIP_STATUS_CHECK
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>
2018-01-08 13:29:10 -08:00
Edward A. James d6bb645a17 hwmon: (pmbus) cffps: Add debugfs entries
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>
2018-01-02 15:05:34 -08:00
Edward A. James eb6489b696 hwmon: (pmbus) Export pmbus device debugfs directory entry
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>
2018-01-02 15:05:34 -08:00
Javier Martinez Canillas 98b16a0986 hwmon: (max31785) Add OF device ID table
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>
2018-01-02 15:05:34 -08:00
Andrew Jeffery cf583b4275 hwmon: (pmbus/max31785) Add dual tachometer support
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>
2018-01-02 15:05:34 -08:00
Andrew Jeffery 464df6fa37 hwmon: (pmbus) Add virtual page config bit
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>
2018-01-02 15:05:34 -08:00
Andrew Jeffery 56ad86b4b1 hwmon: (pmbus/max31785) Add fan control
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>
2018-01-02 15:05:34 -08:00
Andrew Jeffery d206636e76 hwmon: (pmbus) Add fan control support
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>
2018-01-02 15:05:34 -08:00
Guenter Roeck 666c14906b hwmon: (pmbus/lm25066) Drop support for LM25063
LM25063 was never released. Drop support for it.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2018-01-02 15:05:34 -08:00
Robert Lippert bd467e4eab hwmon: (pmbus) Use 64bit math for DIRECT format values
Power values in the 100s of watt range can easily blow past
32bit math limits when processing everything in microwatts.

Use 64bit math instead to avoid these issues on common 32bit ARM
BMC platforms.

Fixes: 442aba7872 ("hwmon: PMBus device driver")
Signed-off-by: Robert Lippert <rlippert@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-11-27 20:29:22 -08:00
Linus Torvalds 1e19bded7f hwmon updates for v4.15
- Drivers for MAX31785 and MAX6621
 - Support for AMD family 17h (Ryzen, Threadripper) temperature sensors
 - Various driver cleanups and minor improvements
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Merge tag 'hwmon-for-linus-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon updates from Guenter Roeck:

 - drivers for MAX31785 and MAX6621

 - support for AMD family 17h (Ryzen, Threadripper) temperature sensors

 - various driver cleanups and minor improvements

* tag 'hwmon-for-linus-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (30 commits)
  dt-bindings: pmbus: Add Maxim MAX31785 documentation
  pmbus: Add driver for Maxim MAX31785 Intelligent Fan Controller
  hwmon: (aspeed-pwm-tacho) Sort headers
  hwmon: (xgene) Minor clean up of ifdef and acpi_match_table reference
  hwmon: (max6621) Inverted if condition in max6621_read()
  hwmon: (asc7621) remove redundant assignment to newval
  hwmon: (xgene) Support hwmon v2
  hwmon: (gpio-fan) Fix null pointer dereference at probe
  hwmon: (gpio-fan) Convert to use GPIO descriptors
  hwmon: (gpio-fan) Rename GPIO line state variables
  hwmon: (gpio-fan) Get rid of the gpio alarm struct
  hwmon: (gpio-fan) Get rid of platform data struct
  hwmon: (gpio-fan) Mandate OF_GPIO and cut pdata path
  hwmon: (gpio-fan) Send around device pointer
  hwmon: (gpio-fan) Localize platform data
  hwmon: (gpio-fan) Use local variable pointers
  hwmon: (gpio-fan) Move DT bindings to the right place
  Documentation: devicetree: add max6621 device
  hwmon: (max6621) Add support for Maxim MAX6621 temperature sensor
  hwmon: (w83793) make const array watchdog_minors static, reduces object code size
  ...
2017-11-13 08:55:46 -08:00
Andrew Jeffery 4d420a6a9d pmbus: Add driver for Maxim MAX31785 Intelligent Fan Controller
The Maxim MAX31785 is a PMBus device providing closed-loop, multi-channel
fan management with temperature and remote voltage sensing. It supports
various fan control features, including PWM frequency control, temperature
hysteresis, dual tachometer measurements, and fan health monitoring.

This patch presents a basic driver using only the existing features of the
PMBus subsystem.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
[groeck: Modified description to clarify that fan control is not yet provided]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-11-05 06:06:33 -08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Edward A. James 6dcf2fb5e8 hwmon: (pmbus/core) Prevent unintentional setting of page to 0xFF
The pmbus core may call read/write word data functions with a page value
of -1, intending to perform the operation without setting the page.
However, the read/write word data functions accept only unsigned 8-bit
page numbers, and therefore cannot check for negative page number to
avoid setting the page. This results in setting the page number to 0xFF.
This may result in errors or undefined behavior of some devices
(specifically the ir35221, which allows the page to be set to 0xFF,
but some subsequent operations to read registers may fail).

Switch the pmbus_set_page page parameter to an integer and perform the
check for negative page there. Make read/write functions consistent in
accepting an integer page number parameter.

Signed-off-by: Edward A. James <eajames@us.ibm.com>
Fixes: cbcdec6202 ("hwmon: (pmbus): Access word data for STATUS_WORD")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-10-29 18:35:54 -07:00
Vadim Pasternak 610526527a hwmon: (pmbus) Add support for Texas Instruments tps53679 device
The below lists of VOUT_MODE command readout with their related VID
protocols, Digital to Analog Converter steps, supported by the device:
VR12.0 mode, 5-mV DAC - 0x21
VR12.5 mode, 10-mV DAC - 0x22
VR13.0 mode, 10-mV DAC - 0x24
IMVP8 mode, 5-mV DAC - 0x25
VR13.0 mode, 5-mV DAC - 0x27

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-30 18:01:08 -07:00
Xo Wang 5783ec2e5c hwmon: (pmbus/lm25066) Add support for TI LM5066I
The TI LM5066I hotswap controller is a more accurate version of the
LM5066 device already supported. It has different measurement conversion
coefficients than the LM5066, so it needs to be recognized as a
different device.

Signed-off-by: Xo Wang <xow@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-30 06:31:13 -07:00
Xo Wang ee983171d4 hwmon: (pmbus/lm25066) Offset coefficient depends on CL
When converting the DIRECT format CURRENT_IN and POWER commands, make
the offset coefficient ("b") predicate on the value of the current limit
setting.

Signed-off-by: Xo Wang <xow@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-30 06:31:12 -07:00
Vadim Pasternak d4977c083a hwmon: (pmbus) Add support for Intel VID protocol VR13
The below lists of VOUT_MODE command readout with their related VID
protocols, Digital to Analog Converter steps:
- VR13.0 mode, 10-mV DAC - 0x24
- VR13.0 mode, 5-mV DAC - 0x27

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-30 06:31:00 -07:00
Edward A. James f69316d62c hwmon: (pmbus) Add IBM Common Form Factor (CFF) power supply driver
Add the driver to monitor IBM CFF power supplies with hwmon over
pmbus.

Signed-off-by: Edward A. James <eajames@us.ibm.com>
[groeck: drop 'default n'; include bitops.h instead of jiffies.h]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-29 18:06:18 -07:00
Edward A. James 1e069dfd96 hwmon: (pmbus) Add debugfs for status registers
Export all the available status registers through debugfs. This is
useful for hardware diagnostics, especially on multi-page pmbus devices,
as user-space access of the i2c space could corrupt the pmbus page
accounting.

Signed-off-by: Edward A. James <eajames@us.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-14 12:22:07 -07:00
Edward A. James c159be9e90 hwmon: (pmbus): Add generic alarm bit for iin and pin
Add PB_STATUS_INPUT as the generic alarm bit for iin and pin. We also
need to redo the status register checking before setting up the boolean
attribute, since it won't necessarily check STATUS_WORD if the device
doesn't support it, which we need for this bit.

Signed-off-by: Edward A. James <eajames@us.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-13 08:24:38 -07:00
Edward A. James cbcdec6202 hwmon: (pmbus): Access word data for STATUS_WORD
Pmbus always reads byte data from the status register, even if
configured to use STATUS_WORD. Use a function pointer to read the
correct amount of data from the registers.
Also switch to try STATUS_WORD first before STATUS_BYTE on init.

Signed-off-by: Edward A. James <eajames@us.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-13 08:24:38 -07:00
Edward A. James a66a6eb9db hwmon: (pmbus): Switch status registers to 16 bit
Switch the storage of status registers to 16 bit values. This allows us
to store all the bits of STATUS_WORD.

Signed-off-by: Edward A. James <eajames@us.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-08-13 08:24:38 -07:00
Wolfram Sang 4ba1bb12cf hwmon: (pmbus) move header file out of I2C realm
include/linux/i2c is not for client devices. Move the header file to a
more appropriate location.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-06-11 17:08:19 -07:00
Samuel Mendoza-Jonas 8991ebd9c9 hwmon: (pmbus) Add client driver for IR35221
IR35221 is a Digital DC-DC Multiphase Converter

Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
[groeck: Preserve alphabetic order in Kconfig;
	add missing break statements (from Dan Carpenter);
	add missing error checks]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-06-11 17:08:19 -07:00
Javier Martinez Canillas 02331c3a1a hwmon: (ucd9200) Add OF device ID table
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.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-04-02 07:01:53 -07:00
Javier Martinez Canillas 8881a19187 hwmon: (ucd9000) Add OF device ID table
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.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-04-02 07:01:53 -07:00
Shikhar Dogra 6faecba0b3 driver: (adm1275) set the m,b and R coefficients correctly for power
Seems like coefficient values for m, b and R under power have been
put in the wrong order. Rearranging them properly to get correct
values of coefficients for power.

For specs, please refer to table 7 (page 35) on
http://www.analog.com/media/en/technical-documentation/data-sheets/ADM1075.pdf

Fixes: 904b296f30 ("hwmon: (adm1275) Introduce configuration data structure for coeffcients")
Signed-off-by: Shikhar Dogra <shidogra@cisco.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-03-27 19:43:36 -07:00
Yi Li 2b3d0c1953 hwmon: (adm1275) Enable adm1278 VOUT sampling
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: Yi Li <adamliyi@msn.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-12-02 13:28:07 -08:00
Matt Weber 50b2b02c40 hwmon: (ucd9000) Add support for UCD90160 Power Supply Sequencer
The UCD90160 Power Supply Sequencer reuses the existing register layout,
so just an id addition was required.

Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Ronak Desai <ronak.desai@rockwellcollins.com>
[groeck: Updated description, ordered alphabetically, added documentation]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-09-08 21:34:16 -07:00
Vadim Pasternak cc00decf0e hwmon: (pmbus) Add explicit support for DPS-460, DPS-800, and SGD009
Provide support for PSU DPS-460, DPS-800 from Delta Electronics, INC
and for SGD009 from Acbel Polytech, INC.

These devices do not support the STATUS_CML register, and reports a
communication error in response to this command. For this reason,
the status register check is disabled for these controllers.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-09-08 21:34:14 -07:00
Guenter Roeck 709066acdd hwmon: (adm1275) Add support for ADM1278
ADM1278 is mostly compatible to other chips of the same series.
Besides the usual difference in coefficients, it supports
a temperature sensor, and it can measure both input and output
voltage at the same time.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-03-05 06:36:03 -08:00
Guenter Roeck 8d28cd1b1f hwmon: (pmbus) Add client driver for LTC3815
LTC3815 is a Monolithic Synchronous DC/DC Step-Down Converter.

Cc: Michael Jones <mike@proclivis.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-12-18 08:20:59 -08:00
Guenter Roeck ccf2dc51bc hwmon: (ltc2978) Add support for LTM4675
LTM2975 is a dual 9A or single 18A μModule regulator.
It is register compatible with LTM4676.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-08-19 09:08:55 -07:00
Michael Jones e04d1ce9bb hwmon: (ltc2978) Add polling for chips requiring it
Some of the LTC chips supported by this driver have to be polled
to ensure that they are ready to accept commands.

Signed-off-by: Michael Jones <mike@proclivis.com>
[Guenter Roeck: simplifications and formatting changes]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-08-19 09:08:41 -07:00
Guenter Roeck d830e27dac hwmon: (pmbus) Enable PEC if the controller supports it
PMBus controllers optionally support PEC. Configure the driver
to use it if available to improve operational security.

Suggested-by: Michael Jones <mike@proclivis.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-08-19 09:08:29 -07:00
Guenter Roeck 2c052d4280 hwmon: (pmbus) Use BIT macro
Using the BIT macro makes the code a little easier to read.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2015-08-19 09:08:17 -07:00