linux/drivers/gpu/drm/amd/display/dc/link/protocols/link_hpd.c

/*
 * Copyright 2022 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: AMD
 *
 */

/* FILE POLICY AND INTENDED USAGE:
 *
 * This file implements functions that manage basic HPD components such as gpio.
 * It also provides wrapper functions to execute HPD related programming. This
 * file only manages basic HPD functionality. It doesn't manage detection or
 * feature or signal specific HPD behaviors.
 */
#include "link_hpd.h"
#include "gpio_service_interface.h"

bool link_get_hpd_state(struct dc_link *link)
{ … }

void link_enable_hpd(const struct dc_link *link)
{ … }

void link_disable_hpd(const struct dc_link *link)
{ … }

void link_enable_hpd_filter(struct dc_link *link, bool enable)
{ … }

struct gpio *link_get_hpd_gpio(struct dc_bios *dcb,
			  struct graphics_object_id link_id,
			  struct gpio_service *gpio_service)
{ … }

bool query_hpd_status(struct dc_link *link, uint32_t *is_hpd_high)
{ … }

enum hpd_source_id get_hpd_line(struct dc_link *link)
{ … }

bool program_hpd_filter(const struct dc_link *link)
{ … }