1*16b2bb7fSKent Gibson.. SPDX-License-Identifier: GPL-2.0 2*16b2bb7fSKent Gibson 3*16b2bb7fSKent Gibson.. _GPIOHANDLE_GET_LINE_VALUES_IOCTL: 4*16b2bb7fSKent Gibson 5*16b2bb7fSKent Gibson******************************** 6*16b2bb7fSKent GibsonGPIOHANDLE_GET_LINE_VALUES_IOCTL 7*16b2bb7fSKent Gibson******************************** 8*16b2bb7fSKent Gibson.. warning:: 9*16b2bb7fSKent Gibson This ioctl is part of chardev_v1.rst and is obsoleted by 10*16b2bb7fSKent Gibson gpio-v2-line-get-values-ioctl.rst. 11*16b2bb7fSKent Gibson 12*16b2bb7fSKent GibsonName 13*16b2bb7fSKent Gibson==== 14*16b2bb7fSKent Gibson 15*16b2bb7fSKent GibsonGPIOHANDLE_GET_LINE_VALUES_IOCTL - Get the values of all requested lines. 16*16b2bb7fSKent Gibson 17*16b2bb7fSKent GibsonSynopsis 18*16b2bb7fSKent Gibson======== 19*16b2bb7fSKent Gibson 20*16b2bb7fSKent Gibson.. c:macro:: GPIOHANDLE_GET_LINE_VALUES_IOCTL 21*16b2bb7fSKent Gibson 22*16b2bb7fSKent Gibson``int ioctl(int handle_fd, GPIOHANDLE_GET_LINE_VALUES_IOCTL, struct gpiohandle_data *values)`` 23*16b2bb7fSKent Gibson 24*16b2bb7fSKent GibsonArguments 25*16b2bb7fSKent Gibson========= 26*16b2bb7fSKent Gibson 27*16b2bb7fSKent Gibson``handle_fd`` 28*16b2bb7fSKent Gibson The file descriptor of the GPIO character device, as returned in the 29*16b2bb7fSKent Gibson :c:type:`request.fd<gpiohandle_request>` by gpio-get-linehandle-ioctl.rst. 30*16b2bb7fSKent Gibson 31*16b2bb7fSKent Gibson``values`` 32*16b2bb7fSKent Gibson The :c:type:`line_values<gpiohandle_data>` to be populated. 33*16b2bb7fSKent Gibson 34*16b2bb7fSKent GibsonDescription 35*16b2bb7fSKent Gibson=========== 36*16b2bb7fSKent Gibson 37*16b2bb7fSKent GibsonGet the values of all requested lines. 38*16b2bb7fSKent Gibson 39*16b2bb7fSKent GibsonThe values of both input and output lines may be read. 40*16b2bb7fSKent Gibson 41*16b2bb7fSKent GibsonFor output lines, the value returned is driver and configuration dependent and 42*16b2bb7fSKent Gibsonmay be either the output buffer (the last requested value set) or the input 43*16b2bb7fSKent Gibsonbuffer (the actual level of the line), and depending on the hardware and 44*16b2bb7fSKent Gibsonconfiguration these may differ. 45*16b2bb7fSKent Gibson 46*16b2bb7fSKent GibsonThis ioctl can also be used to read the line value for line events, 47*16b2bb7fSKent Gibsonsubstituting the ``event_fd`` for the ``handle_fd``. As there is only 48*16b2bb7fSKent Gibsonone line requested in that case, only the one value is returned in ``values``. 49*16b2bb7fSKent Gibson 50*16b2bb7fSKent GibsonReturn Value 51*16b2bb7fSKent Gibson============ 52*16b2bb7fSKent Gibson 53*16b2bb7fSKent GibsonOn success 0 and ``values`` populated with the values read. 54*16b2bb7fSKent Gibson 55*16b2bb7fSKent GibsonOn error -1 and the ``errno`` variable is set appropriately. 56*16b2bb7fSKent GibsonCommon error codes are described in error-codes.rst. 57