linux-yocto - Yocto Linux Embedded kernel

Age	Commit message (Collapse)	Author
2019-11-12	iio: srf04: fix wrong limitation in distance measuring	Andreas Klinger
	commit 431f7667bd6889a274913162dfd19cce9d84848e upstream. The measured time value in the driver is limited to the maximum distance which can be read by the sensor. This limitation was wrong and is fixed by this patch. It also takes into account that we are supporting a variety of sensors today and that the recently added sensors have a higher maximum distance range. Changes in v2: - Added a Tested-by Suggested-by: Zbyněk Kocur <zbynek.kocur@fel.cvut.cz> Tested-by: Zbyněk Kocur <zbynek.kocur@fel.cvut.cz> Signed-off-by: Andreas Klinger <ak@it-klinger.de> Cc:<Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-04	iio: distance: add devantech us ranger srf04	Andreas Klinger
	This patch adds support for the ultrasonic ranger srf04 of devantech. This device is measuring the distance of objects in a range between 1 cm and 3 meters and a theoretical resolution of 3 mm. There are two GPIOs used: - trigger: set as output to the device when the measurement should start - echo: set by the device when the ultrasonic wave is sent out and reset when the echo is recognized; this needs to be an interrupt input The time between setting and resetting the echo pin is the time the waveform needed for one round trip. This time is recorded in the interrupt handler. The distance is calculated in the read function by using the ultrasonic speed at 20 degrees celsius which is about 343 m/s. Signed-off-by: Andreas Klinger <ak@it-klinger.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>