1.. SPDX-License-Identifier: GPL-2.0 2 3.. _GPIO_V2_LINE_GET_VALUES_IOCTL: 4 5***************************** 6GPIO_V2_LINE_GET_VALUES_IOCTL 7***************************** 8 9Name 10==== 11 12GPIO_V2_LINE_GET_VALUES_IOCTL - Get the values of requested lines. 13 14Synopsis 15======== 16 17.. c:macro:: GPIO_V2_LINE_GET_VALUES_IOCTL 18 19``int ioctl(int req_fd, GPIO_V2_LINE_GET_VALUES_IOCTL, struct gpio_v2_line_values *values)`` 20 21Arguments 22========= 23 24``req_fd`` 25 The file descriptor of the GPIO character device, as returned in the 26 :c:type:`request.fd<gpio_v2_line_request>` by gpio-v2-get-line-ioctl.rst. 27 28``values`` 29 The :c:type:`line_values<gpio_v2_line_values>` to get with the ``mask`` set 30 to indicate the subset of requested lines to get. 31 32Description 33=========== 34 35Get the values of requested lines. 36 37The values of both input and output lines may be read. 38 39For output lines, the value returned is driver and configuration dependent and 40may be either the output buffer (the last requested value set) or the input 41buffer (the actual level of the line), and depending on the hardware and 42configuration these may differ. 43 44Return Value 45============ 46 47On success 0 and the corresponding :c:type:`values.bits<gpio_v2_line_values>` 48contain the value read. 49 50On error -1 and the ``errno`` variable is set appropriately. 51Common error codes are described in error-codes.rst. 52