linux-stable.git/drivers/hwmon, branch v4.4.8

hwmon: (max1111) Return -ENODEV from max1111_read_channel if not instantiated

2016-04-20T06:41:52+00:00

commit 3c2e2266a5bd2d1cef258e6e54dca1d99946379f upstream.

arm:pxa_defconfig can result in the following crash if the max1111 driver
is not instantiated.

Unhandled fault: page domain fault (0x01b) at 0x00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: : 1b [#1] PREEMPT ARM
Modules linked in:
CPU: 0 PID: 300 Comm: kworker/0:1 Not tainted 4.5.0-01301-g1701f680407c #10
Hardware name: SHARP Akita
Workqueue: events sharpsl_charge_toggle
task: c390a000 ti: c391e000 task.ti: c391e000
PC is at max1111_read_channel+0x20/0x30
LR is at sharpsl_pm_pxa_read_max1111+0x2c/0x3c
pc : []    lr : []    psr: 20000013
...
[] (max1111_read_channel) from []
					(sharpsl_pm_pxa_read_max1111+0x2c/0x3c)
[] (sharpsl_pm_pxa_read_max1111) from []
					(spitzpm_read_devdata+0x5c/0xc4)
[] (spitzpm_read_devdata) from []
					(sharpsl_check_battery_temp+0x78/0x110)
[] (sharpsl_check_battery_temp) from []
					(sharpsl_charge_toggle+0x48/0x110)
[] (sharpsl_charge_toggle) from []
					(process_one_work+0x14c/0x48c)
[] (process_one_work) from [] (worker_thread+0x3c/0x5d4)
[] (worker_thread) from [] (kthread+0xd0/0xec)
[] (kthread) from [] (ret_from_fork+0x14/0x24)

This can occur because the SPI controller driver (SPI_PXA2XX) is built as
module and thus not necessarily loaded. While building SPI_PXA2XX into the
kernel would make the problem disappear, it appears prudent to ensure that
the driver is instantiated before accessing its data structures.

Cc: Arnd Bergmann 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

hwmon: (ads1015) Handle negative conversion values correctly

2016-03-03T23:07:25+00:00

commit acc146943957d7418a6846f06e029b2c5e87e0d5 upstream.

Make the divisor signed as DIV_ROUND_CLOSEST is undefined for negative
dividends when the divisor is unsigned.

Signed-off-by: Peter Rosin 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

hwmon: (gpio-fan) Remove un-necessary speed_index lookup for thermal hook

2016-03-03T23:07:25+00:00

commit 000e0949148382c4962489593a2f05504c2a6771 upstream.

Thermal hook gpio_fan_get_cur_state is only interested in knowing
the current speed index that was setup in the system, this is
already available as part of fan_data->speed_index which is always
set by set_fan_speed. Using get_fan_speed_index is useful when we
have no idea about the fan speed configuration (for example during
fan_ctrl_init).

When thermal framework invokes
gpio_fan_get_cur_state=>get_fan_speed_index via gpio_fan_get_cur_state
especially in a polled configuration for thermal governor, we
basically hog the i2c interface to the extent that other functions
fail to get any traffic out :(.

Instead, just provide the last state set in the driver - since the gpio
fan driver is responsible for the fan state immaterial of override, the
fan_data->speed_index should accurately reflect the state.

Fixes: b5cf88e46bad ("(gpio-fan): Add thermal control hooks")
Reported-by: Tony Lindgren 
Cc: Guenter Roeck 
Cc: Eduardo Valentin 
Signed-off-by: Nishanth Menon 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

hwmon: (dell-smm) Blacklist Dell Studio XPS 8000

2016-03-03T23:07:25+00:00

commit 6220f4ebd7b4db499238c2dc91268a9c473fd01c upstream.

Since Linux 4.0 the CPU fan speed is going up and down on Dell Studio
XPS 8000 and 8100 for unknown reasons. The 8100 was already
blacklisted in commit a4b45b25f18d ("hwmon: (dell-smm) Blacklist
Dell Studio XPS 8100"). This patch blacklists the XPS 8000.

Without further debugging on the affected machine, it is not possible
to find the problem. For more details see
https://bugzilla.kernel.org/show_bug.cgi?id=100121

Signed-off-by: Thorsten Leemhuis 
Acked-by: Pali Rohár 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

hwmon: (sht15) Select CONFIG_BITREVERSE

2015-12-18T16:19:52+00:00

If CONFIG_BITREVERSE is not built-in, the sht15 driver fails to link:

drivers/built-in.o: In function `sht15_crc8':
drivers/hwmon/sht15.c:195: undefined reference to `byte_rev_table'

This adds a Kconfig 'select' statement, like all other users of
bitrev.h have it.

Signed-off-by: Arnd Bergmann 
Fixes: 33836ee98533 ("hwmon:change sht15_reverse()")
Signed-off-by: Guenter Roeck

hwmon: (tmp102) Force wait for conversion time for the first valid data

2015-12-10T16:14:22+00:00

TMP102 works based on conversions done periodically. However, as per
the TMP102 data sheet[1] the first conversion is triggered immediately
after we program the configuration register. The temperature data
registers do not reflect proper data until the first conversion is
complete (in our case HZ/4).

The driver currently sets the last_update to be jiffies - HZ, just
after the configuration is complete. When TMP102 driver registers
with the thermal framework, it immediately tries to read the sensor
temperature data. This takes place even before the conversion on the
TMP102 is complete and results in an invalid temperature read.

Depending on the value read, this may cause thermal framework to
assume that a critical temperature event has occurred and attempts to
shutdown the system.

Instead of causing an invalid mid-conversion value to be read
erroneously, we mark the last_update to be in-line with the current
jiffies. This allows the tmp102_update_device function to skip update
until the required conversion time is complete. Further, we ensure to
return -EAGAIN result instead of returning spurious temperature (such
as 0C) values to the caller to prevent any wrong decisions made with
such values. NOTE: this allows the read functions not to be blocking
and allows the callers to make the decision if they would like to
block or try again later. At least the current user(thermal) seems to
handle this by retrying later.

A simpler alternative approach could be to sleep in the probe for the
duration required, but that will result in latency that is undesirable
and delay boot sequence un-necessarily.

[1] http://www.ti.com/lit/ds/symlink/tmp102.pdf

Cc: Eduardo Valentin 
Reported-by: Aparna Balasubramanian 
Reported-by: Elvita Lobo 
Reported-by: Yan Liu 
Signed-off-by: Nishanth Menon 
Signed-off-by: Guenter Roeck

hwmon: (scpi) skip unsupported sensors properly

2015-11-16T17:59:50+00:00

Currently it's assumed that firmware exports only the class of sensors
supported by the driver. However with newer firmware or SCPI protocol
revision, support for newer classes of sensors can be present.

The driver fails to probe with the following warning if an unsupported
class of sensor is encountered in the firmware.

sysfs: cannot create duplicate filename
	'/devices/platform/scpi/scpi:sensors/hwmon/hwmon0/'
------------[ cut here ]------------
WARNING: at fs/sysfs/dir.c:31
Modules linked in:

CPU: 0 PID: 6 Comm: kworker/u12:0 Not tainted 4.3.0-rc7 #137
Hardware name: ARM Juno development board (r0) (DT)
Workqueue: deferwq deferred_probe_work_func
PC is at sysfs_warn_dup+0x54/0x78
LR is at sysfs_warn_dup+0x54/0x78

This patch fixes the above issue by skipping through the unsupported
class of SCPI sensors.

Fixes: 68acc77a2d51 ("hwmon: Support thermal zones registration for SCP temperature sensors")
Fixes: ea98b29a05e9 ("hwmon: Support sensors exported via ARM SCP interface")
Cc: Guenter Roeck 
Reviewed-by: Punit Agrawal 
Signed-off-by: Sudeep Holla 
Signed-off-by: Guenter Roeck

hwmon: (scpi) add thermal-of dependency

2015-11-16T17:54:45+00:00

The newly added scpi thermal support is broken when the scpi driver
is built-in but the thermal driver is a loadable module:

drivers/built-in.o: In function `scpi_hwmon_probe':
(.text+0x444d70): undefined reference to `thermal_zone_of_sensor_unregister'
(.text+0x444d94): undefined reference to `thermal_zone_of_sensor_register'
drivers/built-in.o: In function `scpi_hwmon_remove':
(text+0x444e6c): undefined reference to `thermal_zone_of_sensor_unregister'

This uses the same Kconfig trick that we have in a couple of other
drivers already to ensure we can only select the driver in valid
configurations when either THERMAL_OF is disabled, or when with a
dependency on CONFIG_THERMAL that can force SCPI to be a loadable
module in the case I was hitting.

Signed-off-by: Arnd Bergmann 
Fixes: 68acc77a2d51 ("hwmon: Support thermal zones registration for SCP temperature sensors")
Signed-off-by: Guenter Roeck

hwmon : (applesmc) Fix uninitialized variables warnings

2015-11-16T05:52:39+00:00

Fix the following "maybe used uninitialized" warnings by
initializing the variables to keep the compiler quiet.
There is no "used uninitialized" in this case.

  CC [M]  drivers/hwmon/applesmc.o
drivers/hwmon/applesmc.c: In function ‘applesmc_init_smcreg’:
drivers/hwmon/applesmc.c:595:43: warning: ‘right_light_sensor’
may be used uninitialized in this function [-Wmaybe-uninitialized]
  s->num_light_sensors = left_light_sensor + right_light_sensor;
                                           ^
drivers/hwmon/applesmc.c:540:26: note: ‘right_light_sensor’ was
declared here
  bool left_light_sensor, right_light_sensor;
                          ^
drivers/hwmon/applesmc.c:595:43: warning: ‘left_light_sensor’ may
be used uninitialized in this function [-Wmaybe-uninitialized]
  s->num_light_sensors = left_light_sensor + right_light_sensor;
                                           ^
drivers/hwmon/applesmc.c:540:7: note: ‘left_light_sensor’ was
declared here
  bool left_light_sensor, right_light_sensor;
       ^

Signed-off-by: Shuah Khan 
Signed-off-by: Guenter Roeck

hwmon: (ina2xx) Fix build issue by selecting REGMAP_I2C

2015-11-16T05:52:39+00:00

Since a0de56c81fcf ("hwmon: (ina2xx) convert driver to using regmap")
the driver requires REGMAP_I2C to build.  Select it by default
in Kconfig.

Reported-by: Guo Chunrong 
Cc: Marc Titinger 
Signed-off-by: Li Yang 
Fixes: a0de56c81fcf ("hwmon: (ina2xx) convert driver to using regmap")
Signed-off-by: Guenter Roeck