+++ /dev/null
-Kernel driver bh1770glc
-=======================
-
-Supported chips:
-ROHM BH1770GLC
-OSRAM SFH7770
-
-Data sheet:
-Not freely available
-
-Author:
-Samu Onkalo <samu.p.onkalo@nokia.com>
-
-Description
------------
-BH1770GLC and SFH7770 are combined ambient light and proximity sensors.
-ALS and proximity parts operates on their own, but they shares common I2C
-interface and interrupt logic. In principle they can run on their own,
-but ALS side results are used to estimate reliability of the proximity sensor.
-
-ALS produces 16 bit lux values. The chip contains interrupt logic to produce
-low and high threshold interrupts.
-
-Proximity part contains IR-led driver up to 3 IR leds. The chip measures
-amount of reflected IR light and produces proximity result. Resolution is
-8 bit. Driver supports only one channel. Driver uses ALS results to estimate
-reliability of the proximity results. Thus ALS is always running while
-proximity detection is needed.
-
-Driver uses threshold interrupts to avoid need for polling the values.
-Proximity low interrupt doesn't exists in the chip. This is simulated
-by using a delayed work. As long as there is proximity threshold above
-interrupts the delayed work is pushed forward. So, when proximity level goes
-below the threshold value, there is no interrupt and the delayed work will
-finally run. This is handled as no proximity indication.
-
-Chip state is controlled via runtime pm framework when enabled in config.
-
-Calibscale factor is used to hide differences between the chips. By default
-value set to neutral state meaning factor of 1.00. To get proper values,
-calibrated source of light is needed as a reference. Calibscale factor is set
-so that measurement produces about the expected lux value.
-
-SYSFS
------
-
-chip_id
- RO - shows detected chip type and version
-
-power_state
- RW - enable / disable chip. Uses counting logic
- 1 enables the chip
- 0 disables the chip
-
-lux0_input
- RO - measured lux value
- sysfs_notify called when threshold interrupt occurs
-
-lux0_sensor_range
- RO - lux0_input max value
-
-lux0_rate
- RW - measurement rate in Hz
-
-lux0_rate_avail
- RO - supported measurement rates
-
-lux0_thresh_above_value
- RW - HI level threshold value. All results above the value
- trigs an interrupt. 65535 (i.e. sensor_range) disables the above
- interrupt.
-
-lux0_thresh_below_value
- RW - LO level threshold value. All results below the value
- trigs an interrupt. 0 disables the below interrupt.
-
-lux0_calibscale
- RW - calibration value. Set to neutral value by default.
- Output results are multiplied with calibscale / calibscale_default
- value.
-
-lux0_calibscale_default
- RO - neutral calibration value
-
-prox0_raw
- RO - measured proximity value
- sysfs_notify called when threshold interrupt occurs
-
-prox0_sensor_range
- RO - prox0_raw max value
-
-prox0_raw_en
- RW - enable / disable proximity - uses counting logic
- 1 enables the proximity
- 0 disables the proximity
-
-prox0_thresh_above_count
- RW - number of proximity interrupts needed before triggering the event
-
-prox0_rate_above
- RW - Measurement rate (in Hz) when the level is above threshold
- i.e. when proximity on has been reported.
-
-prox0_rate_below
- RW - Measurement rate (in Hz) when the level is below threshold
- i.e. when proximity off has been reported.
-
-prox0_rate_avail
- RO - Supported proximity measurement rates in Hz
-
-prox0_thresh_above0_value
- RW - threshold level which trigs proximity events.
- Filtered by persistence filter (prox0_thresh_above_count)
-
-prox0_thresh_above1_value
- RW - threshold level which trigs event immediately
projects / linux-2.6-microblaze.git / blobdiff