Some chips either don't support it or fail to provide adequate documentation,
so sometimes it's impossible to enable the feature even if it is supported.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
driver for the TSL4531 family of 16-bit I2C ambient light
sensors; information is here:
http://www.ams.com/eng/Products/Light-Sensors/Ambient-Light-Sensor-ALS/TSL45315
the chip offers simple lux output
v3 (thanks Lars-Peter Clausen):
* add mutex to when updating integration time
* fix chip ID checking
* code cleanups
v2:
* rename to tsl4351
* use INT_TIME
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Integration time is in seconds; it controls the measurement
time and influences the gain of a sensor.
There are two typical ways that scaling is implemented in a device:
1) input amplifier,
2) reference to the ADC is changed.
These both result in the accuracy of the ADC varying (by applying its
sampling over a more relevant range).
Integration time is a way of dealing with noise inherent in the analog
sensor itself. In the case of a light sensor, a mixture of photon noise
and device specific noise. Photon noise is dealt with by either improving
the efficiency of the sensor, (more photons actually captured) which is not
easily varied dynamically, or by integrating the measurement over a longer
time period. Note that this can also be thought of as an averaging of a
number of individual samples and is infact sometimes implemented this way.
Altering integration time implies that the duration of a measurement changes,
a fact the device's user may be interested in.
Hence it makes sense to distinguish between integration time and simple
scale. In some devices both types of control are present and whilst they
will have similar effects on the amplitude of the reading, their effect
on the noise of the measurements will differ considerably.
Used by adjd_s311, tsl4531, tcs3472
The following drivers have similar controls (and could be adapted):
* tsl2563 (integration time is controlled via CALIBSCALE among other things)
* tsl2583 (has integration_time device_attr, but driver doesn't use channels yet)
* tsl2x7x (has integration_time attr)
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Jon Brenner <jon.brenner@ams.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
For at91 boards, there are different IPs for adc. Different IPs has different
STARTUP & PRESCAL mask in ADC_MR.
Signed-off-by: Josh Wu <josh.wu@atmel.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
As use the multiple compatible string, we can remove hardware register in dt.
CC: devicetree@vger.kernel.org
Signed-off-by: Josh Wu <josh.wu@atmel.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Fix to return -EINTR in the error handling case instead
of 0 (ret is assigned after goto, which has no effect),
as done elsewhere in this function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Using devm_iio_device_alloc makes code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Roland Stigge <stigge@antcom.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Using devm_iio_device_alloc makes code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Using devm_iio_device_alloc and devm_request_threaded_irq makes
code simpler.
Signed-off-by: Oleksandr Kozaruk <oleksandr.kozaruk@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
using word reads, no need for HI/LO register #defines
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
IIO_VAL_INT_PLUS_MICRO is the default, no need to return it explicitly
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add a resource managed devm_iio_trigger_alloc()/devm_iio_triger_free()
to automatically clean up triggers allocated by IIO drivers, thus
leading to simplified IIO drivers code.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Kyunmin Park <kyungmin.park@samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The GPADC is general purpose ADC found on TWL6030, and TWL6032 PMIC,
known also as Phoenix and PhoenixLite.
The TWL6030 and TWL6032 have GPADC with 17 and 19 channels
respectively. Some channels have current source and are used for
measuring voltage drop on resistive load for detecting battery ID
resistance, or measuring voltage drop on NTC resistors for external
temperature measurements. Some channels measure voltage, (i.e. battery
voltage), and have voltage dividers, thus, capable to scale voltage.
Some channels are dedicated for measuring die temperature.
Some channels are calibrated in 2 points, having offsets from ideal
values kept in trim registers. This is used to correct measurements.
The differences between GPADC in TWL6030 and TWL6032:
- 10 bit vs 12 bit ADC;
- 17 vs 19 channels;
- channels have different purpose(i.e. battery voltage
channel 8 vs channel 18);
- trim values are interpreted differently.
Based on the driver patched from Balaji TK, Graeme Gregory, Ambresh K,
Girish S Ghongdemath.
Signed-off-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Oleksandr Kozaruk <oleksandr.kozaruk@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Using devm_iio_device_alloc makes code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Christian Strobel <christian.strobel@iis.fraunhofer.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Using devm_iio_device_alloc makes code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
the TI TMP006 is a non-contact temperature sensor with I2C interface;
it measures the surface temperature of a distance object using a
thermopile to absorb IR energy emitted from the object
the sensor has two channels: IR sensor voltage (16-bit) and reference
temperature of the chip (14-bit); datasheet is here:
http://www.ti.com/lit/ds/symlink/tmp006.pdf
v2 (thanks to Grygorii Strashko, Lars-Peter Clausen, Jonathan Cameron
for review comments):
* power down device on driver remove
* use sign_extend32()
* style cleanup
* add comments what channel raw LSBs mean
* spelling of thermopile
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: LM Sensors <lm-sensors@lm-sensors.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This reverts commit 98a5e9e99d.
IIO, like the rest of the kernel, should rely on dynamic debugging, not
have a special config option for it. That way, no user has to rebuild
their kernel to have debug messages, which is a good thing, let's not
revert back to the bad old days of the 2000's.
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
devm_* APIs are device managed and make code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Michael Hennerich <hennerich@blackfin.uclinux.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>