TSLLUX(4)

TSLLUX(4) | Device Drivers Manual | TSLLUX(4)

# NAME

`tsllux` —
Taos TSL256x Light-to-Digital Converter

# SYNOPSIS

`tsllux* at iic? addr 0x29 flags 0x0`
`tsllux* at iic? addr 0x39 flags 0x0`
`tsllux* at iic? addr 0x49 flags 0x0`

# DESCRIPTION

The `tsllux` driver provides support for the Taos TSL2560 and TSL2561 light-to-digital converter (ambient light sensor) with the envsys(4) API.

The TSL2560 is designed to work with SMBus at 100 kHz. The TSL2561 is designed to work with I2C Fast-Mode at 400 kHz. The sensors come in a variety of packages, including 6-lead Chipscale (CS), 6-lead TMB (T), dual flat no-lead (FN), and 6-lead ChipLED (CL). The ‘CS’ package requires a different set of coefficients for calculating the Lux value from the raw sensor data. This behavior is enabled by specifying the flag `0x1` in the kernel configuration file or by using a sysctl(8) variable; see below.

The `tsllux` driver exports some sysctl(8) variables to control the behavior of the sensor and driver:

hw.tsllux0.cs_package (boolean, read-write)
  This variable indicates if the driver instance has been configured to use the coeffecients appropriate for the ‘CS’ package variant.
hw.tsllux0.auto_gain (boolean, read-write)
  This variable indicates if the driver has been configured to use an auto-gain algorithm to improve sensitivity of the sensor while taking care to avoid sensor saturation. Auto-gain is disabled by default.
hw.tsllux0.gain (integer, read-write)
  This variable indicates the selected sensor gain. If auto-gain is enabled, this will reflect the current gain setting selected by the auto-gain algorithm. Otherwise, it reflects the previously-configured gain. Valid values are `1` and `16`. The default gain is `1`. Writing to this variable implicitly disables auto-gain.
hw.tsllux0.integration_time (integer, read-write)
  This variable indicates the selected analog-to-digital converter integration time. Longer integration times correspond to more accurate readings, at the cost of more costly read operation. Valid values are `13` (13.7ms), `101` (101ms), and `402` (402ms). The default value is `101`. Note that that due to the granularity of sleep timing in the kernel, the `tsllux` driver will busy-wait for wait times less than 1 Hz, and add an additional sleep clock tick for wait times greater than 1 Hz. See hz(9).

# SEE ALSO

envsys(4), iic(4)

# HISTORY

The `tsllux` driver first appeared in NetBSD 9.0.

# AUTHORS

The `tsllux` driver was written by Jason R Thorpe <thorpej@NetBSD.org>.

# BUGS

The driver does not currently support the sensor's interrupt features or the sensor's manual integration timing feature.

May 21, 2018 | NetBSD 10.1