Commit Graph

19 Commits

Author SHA1 Message Date
Linus Walleij 6282b5c620 iio: pressure: bmp280: BMP280 calibration to entropy
The BMP280/BME280 calibration data should also go into the
entropy pool, like we do for BMP180.

This just adds the temperature and pressure calibration, the
humidity calibration seems like too much annoying calls to
add.

Cc: Tomasz Duszynski <tduszyns@gmail.com>
Cc: Stefan Tatschner <stefan.tatschner@gmail.com>
Cc: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-04-04 20:19:58 +01:00
Tomasz Duszynski 13399ff25f iio: pressure: bmp280: fix relative humidity unit
According to IIO ABI relative humidity reading should be
returned in milli percent.

This patch addresses that by applying proper scaling and
returning integer instead of fractional format type specifier.

Note that the fixes tag is before the driver was heavily refactored
to introduce spi support, so the patch won't apply that far back.

Signed-off-by: Tomasz Duszynski <tduszyns@gmail.com>
Fixes: 14beaa8f5a ("iio: pressure: bmp280: add humidity support")
Acked-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-06-24 14:22:35 +01:00
Stefan Tatschner 2e419aec3b iio:pressure:bmp280: Read calibration data in probe
This patch affects BME280 and BMP280. The readout of the calibration
data is moved to the probe function. Each sensor data access triggered
reading the full calibration data before this patch. According to the
datasheet, Section 4.4.2., the calibration data is stored in non-volatile
memory.

Since the calibration data does not change, and cannot be changed by the
user, we can reduce bus traffic by reading the calibration data once.
Additionally, proper organization of the data types enables removing
some odd casts in the compensation formulas.

Signed-off-by: Stefan Tatschner <stefan.tatschner@gmail.com>
Tested-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-08 16:03:43 +01:00
Greg Kroah-Hartman 1236d6bb6e Merge 4.14-rc4 into staging-next
We want the staging/iio fixes in here as well to handle merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-09 09:02:35 +02:00
Greg Kroah-Hartman 069f0e0c06 Round one of new device support, features and cleanup for IIO in the 4.15 cycle.
Note there is a misc driver drop in here given we have support
 in IIO and the feeling is no one will care.
 
 A large part of this series is a boiler plate removal series avoiding
 the need to explicitly provide THIS_MODULE in various locations.
 It's very dull but touches all drivers.
 
 New device support
 * ad5446
   - add ids to support compatible parts DAC081S101, DAC101S101,
     DAC121S101.
   - add the dac7512 id and drop the misc driver as feeling is no
     one is using it (was introduced for a board that is long obsolete)
 * mt6577
   - add bindings for mt2712 which is fully compatible with other
     supported parts.
 * st_pressure
   - add support for LPS33HW and LPS35HW with bindings (ids mostly).
 
 New features
 * ccs811
   - Add support for the data ready trigger.
 * mma8452
   - remove artifical restriction on supporting multiple event types
     at the same time.
 * tcs3472
   - support out of threshold events
 
 Core and tree wide cleanup
 * Use macro magic to remove the need to provide THIS_MODULE as part of
   struct iio_info or struct iio_trigger_ops.  This is similar to
   work done in a number of other subsystems (e.g. i2c, spi).
 
   All drivers are fixed and then the fields in these structures are
   removed.
 
   This will cause build failures for out of tree drivers and any
   new drivers that cross with this work going into the kernel.
 
   Note mostly done with a coccinelle patch, included in the series
   on the mailing list but not merged as the fields no longer exist
   in the structures so the any hold outs will cause a build failure.
 
 Cleanups
 * ads1015
   - avoid writing config register when it doesn't change.
   - add 10% to conversion wait time as it seems it is sometimes
     a little small.
 * ade7753
   - replace use of core mlock with a local lock.  This is part of a
     long term effort to make the use of mlock opaque and single
     purpose.
 * ade7759
   - expand the use of buf_lock to cover previous mlock cases.  This
     is a slightly nicer solution to the same issue as in ade7753.
 * cros_ec
   - drop an unused variable
 * inv_mpu6050
   - add a missing break in a switch for consistency - not actual
     bug,
   - make some local arrays static to save on object code size.
 * max5481
   - drop manual setting of the spi module owner as handled by the
     spi core.
 * max5487
   - drop manual setting of the spi module owner as handled by the
     spi core.
 * max9611
   - drop explicit setting of the i2c module owner as handled by
     the i2c core.
 * mcp320x
   - speed up reads on single channel devices,
   - drop unused of_device_id data elements,
   - document the struct mcp320x,
   - improve binding docs to reflect restrictions on spi setup and
     to make it explicit that the reference regulator is needed.
 * mma8452
   - symbolic to octal permissions,
   - unsigned to unsigned int.
 * st_lsm6dsx
   - avoid setting odr values multiple times,
   - drop config of LIR as it is only ever set to the existing
     defaults,
   - drop rounding configuration as it only ever matches the defaults.
 * ti-ads8688
   - drop manual setting of the spi module owner as handled by the
     spi core.
 * tsl2x7x
   - constify the i2c_device_id,
   - cleanup limit checks to avoid static checker warnings (and generally
     have nicer code).
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Merge tag 'iio-for-4.15a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Round one of new device support, features and cleanup for IIO in the 4.15 cycle.

Note there is a misc driver drop in here given we have support
in IIO and the feeling is no one will care.

A large part of this series is a boiler plate removal series avoiding
the need to explicitly provide THIS_MODULE in various locations.
It's very dull but touches all drivers.

New device support
* ad5446
  - add ids to support compatible parts DAC081S101, DAC101S101,
    DAC121S101.
  - add the dac7512 id and drop the misc driver as feeling is no
    one is using it (was introduced for a board that is long obsolete)
* mt6577
  - add bindings for mt2712 which is fully compatible with other
    supported parts.
* st_pressure
  - add support for LPS33HW and LPS35HW with bindings (ids mostly).

New features
* ccs811
  - Add support for the data ready trigger.
* mma8452
  - remove artifical restriction on supporting multiple event types
    at the same time.
* tcs3472
  - support out of threshold events

Core and tree wide cleanup
* Use macro magic to remove the need to provide THIS_MODULE as part of
  struct iio_info or struct iio_trigger_ops.  This is similar to
  work done in a number of other subsystems (e.g. i2c, spi).

  All drivers are fixed and then the fields in these structures are
  removed.

  This will cause build failures for out of tree drivers and any
  new drivers that cross with this work going into the kernel.

  Note mostly done with a coccinelle patch, included in the series
  on the mailing list but not merged as the fields no longer exist
  in the structures so the any hold outs will cause a build failure.

Cleanups
* ads1015
  - avoid writing config register when it doesn't change.
  - add 10% to conversion wait time as it seems it is sometimes
    a little small.
* ade7753
  - replace use of core mlock with a local lock.  This is part of a
    long term effort to make the use of mlock opaque and single
    purpose.
* ade7759
  - expand the use of buf_lock to cover previous mlock cases.  This
    is a slightly nicer solution to the same issue as in ade7753.
* cros_ec
  - drop an unused variable
* inv_mpu6050
  - add a missing break in a switch for consistency - not actual
    bug,
  - make some local arrays static to save on object code size.
* max5481
  - drop manual setting of the spi module owner as handled by the
    spi core.
* max5487
  - drop manual setting of the spi module owner as handled by the
    spi core.
* max9611
  - drop explicit setting of the i2c module owner as handled by
    the i2c core.
* mcp320x
  - speed up reads on single channel devices,
  - drop unused of_device_id data elements,
  - document the struct mcp320x,
  - improve binding docs to reflect restrictions on spi setup and
    to make it explicit that the reference regulator is needed.
* mma8452
  - symbolic to octal permissions,
  - unsigned to unsigned int.
* st_lsm6dsx
  - avoid setting odr values multiple times,
  - drop config of LIR as it is only ever set to the existing
    defaults,
  - drop rounding configuration as it only ever matches the defaults.
* ti-ads8688
  - drop manual setting of the spi module owner as handled by the
    spi core.
* tsl2x7x
  - constify the i2c_device_id,
  - cleanup limit checks to avoid static checker warnings (and generally
    have nicer code).
2017-09-25 12:56:37 +02:00
Greg Kroah-Hartman b2e312061c First round of IIO fixes for the 4.14 cycle
Note this includes fixes from recent merge window.  As such the tree
 is based on top of a prior staging/staging-next tree.
 
 * iio core
   - return and error for a failed read_reg debugfs call rather than
     eating the error.
 * ad7192
   - Use the dedicated reset function in the ad_sigma_delta library
     instead of an spi transfer with the data on the stack which
     could cause problems with DMA.
 * ad7793
   - Implement a dedicate reset function in the ad_sigma_delta library
     and use it to correctly reset this part.
 * bme280
   - ctrl_reg write must occur after any register writes
   for updates to take effect.
 * mcp320x
   - negative voltage readout was broken.
   - Fix an oops on module unload due to spi_set_drvdata not being called
     in probe.
 * st_magn
   - Fix the data ready line configuration for the lis3mdl. It is not
     configurable so the st_magn core was assuming it didn't exist
     and so wasn't consuming interrupts resulting in an unhandled
     interrupt.
 * stm32-adc
   - off by one error on max channels checking.
 * stm32-timer
   - preset should not be buffered - reorganising register writes avoids
   this.
   - fix a corner case in which write preset goes wrong when a timer is
   used first as a trigger then as a counter with preset. Odd case but
   you never know.
 * ti-ads1015
   - Fix setting of comparator polarity by fixing bitfield definition.
 * twl4030
   - Error path handling fix to cleanup in event of regulator
     registration failure.
   - Disable the vusb3v1 regulator correctly in error handling
   - Don't paper over a regulator enable failure.
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Merge tag 'iio-fixes-for-4.14a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First round of IIO fixes for the 4.14 cycle

Note this includes fixes from recent merge window.  As such the tree
is based on top of a prior staging/staging-next tree.

* iio core
  - return and error for a failed read_reg debugfs call rather than
    eating the error.
* ad7192
  - Use the dedicated reset function in the ad_sigma_delta library
    instead of an spi transfer with the data on the stack which
    could cause problems with DMA.
* ad7793
  - Implement a dedicate reset function in the ad_sigma_delta library
    and use it to correctly reset this part.
* bme280
  - ctrl_reg write must occur after any register writes
  for updates to take effect.
* mcp320x
  - negative voltage readout was broken.
  - Fix an oops on module unload due to spi_set_drvdata not being called
    in probe.
* st_magn
  - Fix the data ready line configuration for the lis3mdl. It is not
    configurable so the st_magn core was assuming it didn't exist
    and so wasn't consuming interrupts resulting in an unhandled
    interrupt.
* stm32-adc
  - off by one error on max channels checking.
* stm32-timer
  - preset should not be buffered - reorganising register writes avoids
  this.
  - fix a corner case in which write preset goes wrong when a timer is
  used first as a trigger then as a counter with preset. Odd case but
  you never know.
* ti-ads1015
  - Fix setting of comparator polarity by fixing bitfield definition.
* twl4030
  - Error path handling fix to cleanup in event of regulator
    registration failure.
  - Disable the vusb3v1 regulator correctly in error handling
  - Don't paper over a regulator enable failure.
2017-09-25 10:58:22 +02:00
Colin Parker 4b1f0c31f9 IIO: BME280: Updates to Humidity readings need ctrl_reg write!
The ctrl_reg register needs to be written after any write to
the humidity registers. The value written to the ctrl_reg register
does not necessarily need to change, but a write operation must
occur.

The regmap_update_bits functions will not write to a register
if the register value matches the value to be written. This saves
unnecessary bus operations.  The change in this patch forces a bus
write during the chip_config operation by switching to
regmap_write_bits.

This will fix issues where the Humidity Sensor Oversampling bits
are not updated after initialization.

Signed-off-by: Colin Parker <colin.parker@aclima.io>
Acked-by: Andreas Klinger <ak@it-klinger.de>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-09-24 16:58:14 +01:00
Jonathan Cameron 6a15fef2cb iio:pressure: drop assign iio_info.driver_module and iio_trigger_ops.owner
The equivalent of both of these are now done via macro magic when
the relevant register calls are 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>
2017-08-22 21:35:27 +01:00
Andreas Klinger eb92b4183d iio: bmp280: properly initialize device for humidity reading
If the device is not initialized at least once it happens that the humidity
reading is skipped, which means the special value 0x8000 is delivered.

For omitting this case the oversampling of the humidity must be set before
the oversampling of the temperature und pressure is set as written in the
datasheet of the BME280.

Furthermore proper error detection is added in case a skipped value is read
from the device. This is done also for pressure and temperature reading.
Especially it don't make sense to compensate this value and treat it as
regular value.

Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-07-30 14:41:12 +01:00
Andreas Klinger ed3730c435 IIO: bmp280-core.c: fix error in humidity calculation
While calculating the compensation of the humidity there are negative values
interpreted as unsigned because of unsigned variables used.  These values as
well as the constants need to be casted to signed as indicated by the
documentation of the sensor.

Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Matt Ranostay <matt.ranostay@konsulko.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-04-14 16:54:49 +01:00
Aniroop Mathur 071cf24943 IIO: Change msleep to usleep_range for small msecs
msleep(1~20) may not do what the caller intends, and will often sleep longer.
(~20 ms actual sleep for any value given in the 1~20ms range)
This is not the desired behaviour for many cases like device resume time,
device suspend time, device enable time, data reading time, etc.
Thus, change msleep to usleep_range for precise wakeups.

Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-12-03 08:58:40 +00:00
Linus Walleij 31f453eac5 iio: pressure: bmp280: fix runtime suspend/resume crash
In commit 3d838118c6 ("iio: pressure: bmp280: add power management")

For some reason the code in the runtime suspend/resume hooks
got wrong (I suspect in the ambition to cut down boilerplate)
and it seems it was tested without CONFIG_PM and crashes like
so for me:

Unable to handle kernel NULL pointer dereference at virtual address 0000000c
pgd = c0204000
[0000000c] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 1 PID: 89 Comm: kworker/1:2 Not tainted
  4.7.0-03348-g90dc3680458a-dirty #99
Hardware name: Generic DT based system
Workqueue: pm pm_runtime_work
task: df3c6300 ti: dec8a000 task.ti: dec8a000
PC is at regulator_disable+0x0/0x6c
LR is at bmp280_runtime_suspend+0x3c/0xa4

Dereferencing the BMP280 state container properly fixes the problem,
sorry for screwing up.

Fixes: 3d838118c6 ("iio: pressure: bmp280: add power management")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-15 15:46:06 +01:00
Wei Yongjun bb9947c3a1 iio: pressure: bmp280: fix wrong pointer passed to PTR_ERR()
PTR_ERR should access the value just tested by IS_ERR, otherwise
the wrong error code will be returned.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-15 15:38:59 +01:00
Linus Walleij b33b7d5ac3 iio: pressure: bmp280: read calibration data once
The calibration data is described as coming from an E2PROM and that
means it does not change. Just read it once at probe time and store
it in the device state container. Also toss the calibration data
into the entropy pool since it is device unique.

Reviewed-by: Vlad Dogaru <vlad.dogaru@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-07-03 11:32:15 +01:00
Linus Walleij 3d838118c6 iio: pressure: bmp280: add power management
The PM280 has an internal standby-mode, but to really save power
we should shut the sensor down and disconnect the power. With
the proper .pm hooks we can enable both runtime and system power
management of the sensor. We use the *force callbacks from the
system PM hooks. When the sensor comes back we always reconfigure
it to make sure it is ready to roll as expected.

Cc: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-07-03 11:32:14 +01:00
Linus Walleij aae9539496 iio: pressure: bmp280: add support for BMP085 EOC interrupt
The first version of this sensor, BMP085, supports sending an
End-of-Conversion (EOC) interrupt. Add code to support this using
a completion, in a similar vein as drivers/misc/bmp085.c does.

Make sure to check that we are given a rising edge, because the
EOC line goes from low-to-high when the conversion is ready.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-07-03 11:32:14 +01:00
Linus Walleij b26b4e9170 iio: pressure: bmp280: add SPI interface driver
This patch mimics the SPI functionality found in the misc driver in
drivers/misc/bh085-spi.c to make it possible to reuse the existing
BMP280/BMP180/BMP085 driver with all clients of the other driver.
The adoption is straight-forward since like the other driver, it is
a simple matter of using regmap.

This driver is also so obviously inspired/copied from the old misc
driver in drivers/misc/bmp085.c that I just took the liberty to
add in the authors of the other drivers + self in the core driver
file.

The MISC driver also supports a variant named "BMP181" so include
that here to be complete in comparison to the old driver.

The bus mapping code for SPI was written by Akinobu Mita.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Tested-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-07-03 11:27:15 +01:00
Linus Walleij 17118843a5 iio: pressure: bmp280: split off an I2C Kconfig entry
This creates a separate BMP280_I2C Kconfig entry that gets selected
by BMP280 for I2C transport. As we currently only support I2C
transport there is not much practical change other than getting
a separate object file (or module) for the I2C driver part. The
old Kconfig symbol BMP280 will still select the stuff we need so
that oldconfig and old defconfigs works fine.

Tested-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-07-03 11:27:14 +01:00
Linus Walleij 14e8015f85 iio: pressure: bmp280: split driver in logical parts
This splits the BMP280 driver in three logical parts: the core driver
bmp280-core that only operated on a struct device * and a struct regmap *,
the regmap driver bmp280-regmap that can be shared between I2C and other
transports and the I2C module driver bmp280-i2c.

Cleverly bake all functionality into a single object bmp280.o so that
we still get the same module binary built for the device in the end,
without any fuzz exporting symbols to the left and right.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-07-03 11:27:11 +01:00