This is a driver for LPS331AP barometer device. It was tested with Samsung Exynos4x12 PQ/M0 board. The device exposes two interrupt pins, but the driver uses only one optional interrupt source. It needs to be stressed that only configuration with INT2 interrupt source could have been tested due to the available PCB layout. Output data from the device can be read in two ways - on demand and by initiating IIO events for the device. The former mode allows for power saving as it instructs the device to do a 'one shot' measurement and return to the power down mode, whereas the latter enables cyclic measurements with the period managed through the 'odr' attribute, where possible settings are: 40ms, 80ms, 143ms and 1000ms. The value has to be given in miliseconds. Every integer value is accepted - the driver will round it to the nearest bottom 'odr' setting. Whereas 'one shot' mode can be used without enabled interrupts, by using read_raw callback, the cyclic measurements can be enabled only when there is at least one interrupt source available. The cyclic measurement mode is activated by enabling one of the two events. In this mode it is also possible to read the output data through the read_raw callback - the driver returns periodically cached data then, not being forced to initiate 'one shot' mode, and making the read operation almost immediate. Read pressures and temperatures output can be converted in units of measurement by dividing them respectively through in_pressure_scale and in_temp_scale. Temperature values must then be added by the constant float in_temp_offset expressed as Celsius degrees. Thanks, Jacek Anaszewski Jacek Anaszewski (1): iio: lps331ap: Add new driver for the device .../devicetree/bindings/iio/barometer/lps331ap.txt | 40 + drivers/iio/Kconfig | 1 + drivers/iio/Makefile | 1 + drivers/iio/barometer/Kconfig | 12 + drivers/iio/barometer/Makefile | 7 + drivers/iio/barometer/lps331ap.c | 1252 ++++++++++++++++++++ 6 files changed, 1313 insertions(+), 0 deletions(-) create mode 100644 Documentation/devicetree/bindings/iio/barometer/lps331ap.txt create mode 100644 drivers/iio/barometer/Kconfig create mode 100644 drivers/iio/barometer/Makefile create mode 100644 drivers/iio/barometer/lps331ap.c -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
