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>
Based on 3 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1105 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
add Maxbotix LV ultrasonic sensor types mb1000, mb1010, mb1020, mb1030
and mb1040
add a configuration struct with the different trigger pulse lengths
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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>
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>
Andreas Klinger