summaryrefslogtreecommitdiff
path: root/drivers/iio/temperature/mlx90614.c
AgeCommit message (Collapse)AuthorFilesLines
2023-09-11iio: mlx90614: Use i2c_get_match_data()Biju Das1-1/+1
Replace device_get_match_data()->i2c_get_match_data() to extend matching support for ID table. Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Acked-by: "Crt Mori <cmo@melexis.com>" Link: https://lore.kernel.org/r/20230812162222.200004-1-biju.das.jz@bp.renesas.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-07-23iio: adc: Explicitly include correct DT includesRob Herring1-1/+1
The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Link: https://lore.kernel.org/r/20230714174628.4057920-1-robh@kernel.org Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-05-23iio: mlx90614: Add MLX90615 supportMarek Vasut1-4/+44
Add support for MLX90615 Infra Red Thermometer, which seems to be the predecesor of MLX90614 . There are significant differences in the register layout compared to MLX90614, but the functionality of the device is virtually identical. The following differences have been identified: - RAM/EEPROM/SLEEP access opcodes are different - RAM/EEPROM registers are at different offsets - EEPROM emissivity and configuration registers are at different offsets - EEPROM configuration register bits are shuffled around - EEPROM emissivity settings are 14 bit on MLX90615 , 16 bit on MLX90614 - MLX90615 can only ever support one sensor, MLX90614 could support two - FIR filter is set to fixed settings on MLX90615 - IIR filter coefficients are different This patch fills in the MLX90615 specific description and quirk handling. The IIR filter coefficients were provided by Melexis as follows: 0b0000 - Forbidden value 0b0001 - 100% - settling time = refresh rate = 205ms (around 5Hz) 0b0010 - 50% - settling time = 2050ms (around 0.5Hz) 0b0011 - 33% - settling time = 36900ms (around 0.3Hz) 0b0100 - 25% - settling time = 5125ms (around 0.2Hz) 0b0101 - 20% - settling time = 6355ms (around 0.15Hz) 0b0110 - 17% - settling time = 7790ms (around 0.13Hz) 0b0111 - 14% - settling time = 9225ms (around 0.1Hz) Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Crt Mori <cmo@melexis.com> Link: https://lore.kernel.org/r/20230510102251.10118-6-marex@denx.de Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-05-23iio: mlx90614: Factor our register IO and constants into model specific ↵Marek Vasut1-59/+122
descriptor Factor out all the differences between MLX90614 and other similar chips into a structure which describes the chip and allows abstracting out the differences from the driver code. No functional change. This patch moves all the RAM and EEPROM IO opcodes into the descriptor structure and combines them, instead of combining the opcode and offset in macros. Acked-by: Crt Mori <cmo@melexis.com> Tested-by: Crt Mori <cmo@melexis.com> Signed-off-by: Marek Vasut <marex@denx.de> Link: https://lore.kernel.org/r/20230510102251.10118-5-marex@denx.de Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-05-23iio: mlx90614: Drop MLX90614_CONST_EMISSIVITY_RESOLUTIONMarek Vasut1-3/+3
The MLX90614_CONST_EMISSIVITY_RESOLUTION can be calculated from MLX90614_CONST_RAW_EMISSIVITY_MAX, perform the calculation inline and drio the MLX90614_CONST_EMISSIVITY_RESOLUTION. Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Crt Mori <cmo@melexis.com> Link: https://lore.kernel.org/r/20230510102251.10118-4-marex@denx.de Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-05-23iio: mlx90614: Drop unused register macrosMarek Vasut1-4/+0
To simplify addition of support for new parts, drop unused register macros. No functional change. Acked-by: Crt Mori <cmo@melexis.com> Signed-off-by: Marek Vasut <marex@denx.de> Link: https://lore.kernel.org/r/20230510102251.10118-3-marex@denx.de Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-05-23iio: mlx90614: Sort headersMarek Vasut1-3/+3
Sort the headers alphabetically. No functional change. Acked-by: Crt Mori <cmo@melexis.com> Signed-off-by: Marek Vasut <marex@denx.de> Link: https://lore.kernel.org/r/20230510102251.10118-2-marex@denx.de Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-05-21iio: Switch i2c drivers back to use .probe()Uwe Kleine-König1-1/+1
After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new() call-back type"), all drivers being converted to .probe_new() and then 03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert back to (the new) .probe() to be able to eventually drop .probe_new() from struct i2c_driver. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20230515205048.19561-1-u.kleine-koenig@pengutronix.de Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2022-11-23iio: temperature: mlx90614: Convert to i2c's .probe_new()Uwe Kleine-König1-3/+3
.probe_new() doesn't get the i2c_device_id * parameter, so determine that explicitly in the probe function. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Crt Mori<cmo@melexis.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20221118224540.619276-186-uwe@kleine-koenig.org Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2022-10-08Merge tag 'char-misc-6.1-rc1' of ↵Linus Torvalds1-11/+30
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc and other driver updates from Greg KH: "Here is the large set of char/misc and other small driver subsystem changes for 6.1-rc1. Loads of different things in here: - IIO driver updates, additions, and changes. Probably the largest part of the diffstat - habanalabs driver update with support for new hardware and features, the second largest part of the diff. - fpga subsystem driver updates and additions - mhi subsystem updates - Coresight driver updates - gnss subsystem updates - extcon driver updates - icc subsystem updates - fsi subsystem updates - nvmem subsystem and driver updates - misc driver updates - speakup driver additions for new features - lots of tiny driver updates and cleanups All of these have been in the linux-next tree for a while with no reported issues" * tag 'char-misc-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (411 commits) w1: Split memcpy() of struct cn_msg flexible array spmi: pmic-arb: increase SPMI transaction timeout delay spmi: pmic-arb: block access for invalid PMIC arbiter v5 SPMI writes spmi: pmic-arb: correct duplicate APID to PPID mapping logic spmi: pmic-arb: add support to dispatch interrupt based on IRQ status spmi: pmic-arb: check apid against limits before calling irq handler spmi: pmic-arb: do not ack and clear peripheral interrupts in cleanup_irq spmi: pmic-arb: handle spurious interrupt spmi: pmic-arb: add a print in cleanup_irq drivers: spmi: Directly use ida_alloc()/free() MAINTAINERS: add TI ECAP driver info counter: ti-ecap-capture: capture driver support for ECAP Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows items dt-bindings: counter: add ti,am62-ecap-capture.yaml counter: Introduce the COUNTER_COMP_ARRAY component type counter: Consolidate Counter extension sysfs attribute creation counter: Introduce the Count capture component counter: 104-quad-8: Add Signal polarity component counter: Introduce the Signal polarity component counter: interrupt-cnt: Implement watch_validate callback ...
2022-09-21iio: temperature: mlx90614 Refactoring available filter attributesCrt Mori1-11/+30
Change/refactor to the new way of defining available attribute values. Signed-off-by: Crt Mori <cmo@melexis.com> Link: https://lore.kernel.org/r/20220906112632.244453-1-cmo@melexis.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2022-08-16i2c: Make remove callback return voidUwe Kleine-König1-3/+1
The value returned by an i2c driver's remove function is mostly ignored. (Only an error message is printed if the value is non-zero that the error is ignored.) So change the prototype of the remove function to return no value. This way driver authors are not tempted to assume that passing an error to the upper layer is a good idea. All drivers are adapted accordingly. There is no intended change of behaviour, all callbacks were prepared to return 0 before. Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com> Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Crt Mori <cmo@melexis.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013 Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/* Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5 Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860 Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power Acked-by: Krzysztof Hałasa <khalasa@piap.pl> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-02-18iio:temperature:mlx90614: Switch from CONFIG_PM* guards to pm_ptr() etcJonathan Cameron1-8/+4
Letting the compiler remove these functions when the kernel is built without one or more of CONFIG_PM/CONFIG_PM_SLEEP support is simpler and less error prone than the use of #ifdef based config guards. Removing instances of this approach from IIO also stops them being copied into new drivers. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Crt Mori <cmo@melexis.com> Reviewed-by: Crt Mori <cmo@melexis.com> Reviewed-by: Paul Cercueil <paul@crapouillou.net> Link: https://lore.kernel.org/r/20220130193147.279148-43-jic23@kernel.org
2021-05-17iio: temp: mlx90614: Handle failure in pm_runtime_resume_and_get()Jonathan Cameron1-5/+20
Converts from using pm_runtime_get_sync() with no error handling over to pm_runtime_resume_and_get() which will ensure we don't end up holding a reference. Ensure this error return is then handled at calls to mlx90614_power_get(). These are all direct returns. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/20210509113354.660190-25-jic23@kernel.org
2020-06-14iio: remove explicit IIO device parent assignmentAlexandru Ardelean1-1/+0
This patch applies the semantic patch: @@ expression I, P, SP; @@ I = devm_iio_device_alloc(P, SP); ... - I->dev.parent = P; It updates 302 files and does 307 deletions. This semantic patch also removes some comments like '/* Establish that the iio_dev is a child of the i2c device */' But this is is only done in case where the block is left empty. The patch does not seem to cover all cases. It looks like in some cases a different variable is used in some cases to assign the parent, but it points to the same reference. In other cases, the block covered by ... may be just too big to be covered by the semantic patch. However, this looks pretty good as well, as it does cover a big bulk of the drivers that should remove the parent assignment. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 330Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this file is subject to the terms and conditions of version 2 of the gnu general public license see the file copying in the main directory of this archive for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 55 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.108941081@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-13i2c: remove i2c_lock_adapter and use i2c_lock_bus directlyPeter Rosin1-2/+2
The i2c_lock_adapter name is ambiguous since it is unclear if it refers to the root adapter or the adapter you name in the argument. The natural interpretation is the adapter you name in the argument, but there are historical reasons for that not being the case; it in fact locks the root adapter. Just remove the function and force users to spell out the I2C_LOCK_ROOT_ADAPTER name to indicate what is really going on. Also remove i2c_unlock_adapter, of course. This patch was generated with git grep -l 'i2c_\(un\)\?lock_adapter' \ | xargs sed -i 's/i2c_\(un\)\?lock_adapter(\([^)]*\))/'\ 'i2c_\1lock_bus(\2, I2C_LOCK_ROOT_ADAPTER)/g' followed by white-space touch-up. Signed-off-by: Peter Rosin <peda@axentia.se> Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com> Tested-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-23iio:temperature: drop assignment of iio_info.driver_moduleJonathan Cameron1-1/+0
The equivalent of this is now done via macro magic when the relevant register call is made. The actual structure elements will shortly go away. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
2017-03-19iio: mlx96014: Add OF device ID tableJavier Martinez Canillas1-0/+7
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> Tested-by: Crt Mori <cmo@melexis.com> Acked-by: Crt Mori <cmo@melexis.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-02-27iio: convert to common i2c_check_functionality() return valueMatt Ranostay1-1/+1
Previously most drivers that used a i2c_check_functionality() check condition required various error codes on failure. This patchset converts to a standard of -EOPNOTSUPP Signed-off-by: Matt Ranostay <mranostay@gmail.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-10-03iio: mlx96014: Error checking from positive to negativeCrt Mori1-6/+8
Dan Carpenter reported a static checker report and after his mail I noticed that we actually return from function if positive value is obtained from i2c read. This was remainder from when code was not in separate function (which I changed during the review process). Static checker reported drivers/iio/temperature/mlx90614.c:167 mlx90614_iir_search() warn: this cast is a no-op which meant that cast before negating is useless. Dan also proposed a solution on nicer bit operation form. Also changed magic number to macro in process as that was confusing. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Crt Mori <cmo@melexis.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-27iio: mlx90614: Implement filter configurationCrt Mori1-3/+87
Implemented Low pass 3db frequency filter which configures FIR and IIR values within the configuration register of EEPROM. For more standardized interface we have fixed the FIR value to 1024, while changes in IIR value are directly connected to filter responses. The new datasheet version will provide a simplified table (also in reStructured text format below) with this change, to provide quick overview of possible settings. Below sensor timings (bandwidth) are calculated for 3db frequency low pass filter. +--------------------+-----------------+ | Filter setting (%) | Band width (Hz) | | (rounded to 1.0) | | +====================+=================+ | 13 | 0.15 | +--------------------+-----------------+ | 17 | 0.20 | +--------------------+-----------------+ | 25 | 0.31 | +--------------------+-----------------+ | 50 | 0.77 | +--------------------+-----------------+ | 57 | 0.86 | +--------------------+-----------------+ | 67 | 1.10 | +--------------------+-----------------+ | 80 | 1.53 | +--------------------+-----------------+ | 100 | 7.23 | +--------------------+-----------------+ The diff is made towards togreg branch. Added myself to MAINTAINERS and authors as per discussion with Jonathan. Signed-off-by: Crt Mori <cmo@melexis.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-02iio: mlx90614: Define magic numbersCrt Mori1-6/+14
Translates the magic constant numbers to named macros and add some additional comments about their meaning. The diff is made towards togreg branch as that branch seems to have the most recent updates of mlx90614 driver (many are yet to be merged). Signed-off-by: Crt Mori <cmo@melexis.com> Acked-by: Peter Meerwald <pmeerw@pmeerw.net> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-07-11iio: Drop owner assignment from i2c_driverKrzysztof Kozlowski1-1/+0
i2c_driver does not need to set an owner because i2c_register_driver() will set it. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-05-13iio:temp:mlx90614 trivial drop of unnecessary ret return from write_raw.Jonathan Cameron1-3/+1
This is mostly part of an effort to clean out our current warnings and make the autobuilder build reports more useful. Still a worthwhile if trivial cleanup! Signed-off-by: Jonathan Cameron <jic23@kernel.org> Reported-by: kbuild test robot <fengguang.wu@intel.com> Cc: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Peter Meerwald <pmeerw@pmeerw.net>
2015-04-18iio: mlx90614: Fix duplicate const warningVianney le Clément de Saint-Marcq1-1/+1
Fix a typo triggering a duplicate const warning on some compilers. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-04-09iio: mlx90614: Check for errors in read valuesVianney le Clément de Saint-Marcq1-0/+5
The device uses the MSB of the returned temperature value as an error flag. Return a read error when this bit is set. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-04-09iio: mlx90614: Add power managementVianney le Clément de Saint-Marcq1-2/+244
Add support for system sleep and runtime power management. To wake up the device, the SDA line should be held low for at least 33ms while SCL is high. As this is not possible using the i2c API (and not supported by all i2c adapters), a GPIO connected to the SDA line is needed. The GPIO is named "wakeup" and can be specified in a device tree with the "wakeup-gpios" binding. If the wake-up GPIO is not given, disable power management for the device. Entering sleep requires an SMBus byte access, hence power management is also disabled if byte access is not supported by the adapter. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-04-09iio: mlx90614: Add emissivity settingVianney le Clément de Saint-Marcq1-3/+103
The mapping from the 16-bit EEPROM value to the decimal 0-1 range is approximate. A special case ensures 0xFFFF shows as 1.0 instead of 0.999998565. Writing to EEPROM requires an explicit erase by writing zero. In addition, it takes 20ms for the erase/write to complete. During this time no EEPROM register should be accessed. Therefore, two msleep()s are added to the write function and a mutex protects against concurrent access. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-03-29iio: mlx90614: Support devices with dual IR sensorVianney le Clément de Saint-Marcq1-10/+57
The model is detected by reading the EEPROM configuration during probing. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-03-29iio: mlx90614: Add symbols for accessible registersVianney le Clément de Saint-Marcq1-1/+25
Add symbols for all accessible RAM and EEPROM registers, as well as the sleep command and timings defined in the datasheet. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-03-09iio: mlx90614: Refactor register symbolsVianney le Clément de Saint-Marcq1-4/+4
The defined registers only make sense when used for accessing RAM. Make MLX90614_OP_RAM part of the symbol definition to avoid accidental access to the wrong register. Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com> Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-05-03iio: Add Melexis mlx90614 contact-less infrared temperature sensor driverPeter Meerwald1-0/+150
I2C-controlled sensor measures ambient and object temperatuer see http://www.melexis.com/Infrared-Thermometer-Sensors/Infrared-Thermometer-Sensors/MLX90614-615.aspx Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net> Signed-off-by: Jonathan Cameron <jic23@kernel.org>