linux/drivers/acpi/nhlt.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright(c) 2023-2024 Intel Corporation
 *
 * Authors: Cezary Rojewski <[email protected]>
 *          Amadeusz Slawinski <[email protected]>
 */

#define pr_fmt(fmt) …

#include <linux/acpi.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/minmax.h>
#include <linux/printk.h>
#include <linux/types.h>
#include <acpi/nhlt.h>

static struct acpi_table_nhlt *acpi_gbl_nhlt;

static struct acpi_table_nhlt empty_nhlt = …;

/**
 * acpi_nhlt_get_gbl_table - Retrieve a pointer to the first NHLT table.
 *
 * If there is no NHLT in the system, acpi_gbl_nhlt will instead point to an
 * empty table.
 *
 * Return: ACPI status code of the operation.
 */
acpi_status acpi_nhlt_get_gbl_table(void)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * acpi_nhlt_put_gbl_table - Release the global NHLT table.
 */
void acpi_nhlt_put_gbl_table(void)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * acpi_nhlt_endpoint_match - Verify if an endpoint matches criteria.
 * @ep:			the endpoint to check.
 * @link_type:		the hardware link type, e.g.: PDM or SSP.
 * @dev_type:		the device type.
 * @dir:		stream direction.
 * @bus_id:		the ID of virtual bus hosting the endpoint.
 *
 * Either of @link_type, @dev_type, @dir or @bus_id may be set to a negative
 * value to ignore the parameter when matching.
 *
 * Return: %true if endpoint matches specified criteria or %false otherwise.
 */
bool acpi_nhlt_endpoint_match(const struct acpi_nhlt_endpoint *ep,
			      int link_type, int dev_type, int dir, int bus_id)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * acpi_nhlt_tb_find_endpoint - Search a NHLT table for an endpoint.
 * @tb:			the table to search.
 * @link_type:		the hardware link type, e.g.: PDM or SSP.
 * @dev_type:		the device type.
 * @dir:		stream direction.
 * @bus_id:		the ID of virtual bus hosting the endpoint.
 *
 * Either of @link_type, @dev_type, @dir or @bus_id may be set to a negative
 * value to ignore the parameter during the search.
 *
 * Return: A pointer to endpoint matching the criteria, %NULL if not found or
 * an ERR_PTR() otherwise.
 */
struct acpi_nhlt_endpoint *
acpi_nhlt_tb_find_endpoint(const struct acpi_table_nhlt *tb,
			   int link_type, int dev_type, int dir, int bus_id)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * acpi_nhlt_find_endpoint - Search all NHLT tables for an endpoint.
 * @link_type:		the hardware link type, e.g.: PDM or SSP.
 * @dev_type:		the device type.
 * @dir:		stream direction.
 * @bus_id:		the ID of virtual bus hosting the endpoint.
 *
 * Either of @link_type, @dev_type, @dir or @bus_id may be set to a negative
 * value to ignore the parameter during the search.
 *
 * Return: A pointer to endpoint matching the criteria, %NULL if not found or
 * an ERR_PTR() otherwise.
 */
struct acpi_nhlt_endpoint *
acpi_nhlt_find_endpoint(int link_type, int dev_type, int dir, int bus_id)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * acpi_nhlt_endpoint_find_fmtcfg - Search endpoint's formats configuration space
 *                                  for a specific format.
 * @ep:			the endpoint to search.
 * @ch:			number of channels.
 * @rate:		samples per second.
 * @vbps:		valid bits per sample.
 * @bps:		bits per sample.
 *
 * Return: A pointer to format matching the criteria, %NULL if not found or
 * an ERR_PTR() otherwise.
 */
struct acpi_nhlt_format_config *
acpi_nhlt_endpoint_find_fmtcfg(const struct acpi_nhlt_endpoint *ep,
			       u16 ch, u32 rate, u16 vbps, u16 bps)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * acpi_nhlt_tb_find_fmtcfg - Search a NHLT table for a specific format.
 * @tb:			the table to search.
 * @link_type:		the hardware link type, e.g.: PDM or SSP.
 * @dev_type:		the device type.
 * @dir:		stream direction.
 * @bus_id:		the ID of virtual bus hosting the endpoint.
 *
 * @ch:			number of channels.
 * @rate:		samples per second.
 * @vbps:		valid bits per sample.
 * @bps:		bits per sample.
 *
 * Either of @link_type, @dev_type, @dir or @bus_id may be set to a negative
 * value to ignore the parameter during the search.
 *
 * Return: A pointer to format matching the criteria, %NULL if not found or
 * an ERR_PTR() otherwise.
 */
struct acpi_nhlt_format_config *
acpi_nhlt_tb_find_fmtcfg(const struct acpi_table_nhlt *tb,
			 int link_type, int dev_type, int dir, int bus_id,
			 u16 ch, u32 rate, u16 vbps, u16 bps)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * acpi_nhlt_find_fmtcfg - Search all NHLT tables for a specific format.
 * @link_type:		the hardware link type, e.g.: PDM or SSP.
 * @dev_type:		the device type.
 * @dir:		stream direction.
 * @bus_id:		the ID of virtual bus hosting the endpoint.
 *
 * @ch:			number of channels.
 * @rate:		samples per second.
 * @vbps:		valid bits per sample.
 * @bps:		bits per sample.
 *
 * Either of @link_type, @dev_type, @dir or @bus_id may be set to a negative
 * value to ignore the parameter during the search.
 *
 * Return: A pointer to format matching the criteria, %NULL if not found or
 * an ERR_PTR() otherwise.
 */
struct acpi_nhlt_format_config *
acpi_nhlt_find_fmtcfg(int link_type, int dev_type, int dir, int bus_id,
		      u16 ch, u32 rate, u16 vbps, u16 bps)
{ … }
EXPORT_SYMBOL_GPL(…);

static bool acpi_nhlt_config_is_micdevice(struct acpi_nhlt_config *cfg)
{ … }

static bool acpi_nhlt_config_is_vendor_micdevice(struct acpi_nhlt_config *cfg)
{ … }

/**
 * acpi_nhlt_endpoint_mic_count - Retrieve number of digital microphones for a PDM endpoint.
 * @ep:			the endpoint to return microphones count for.
 *
 * Return: A number of microphones or an error code if an invalid endpoint is provided.
 */
int acpi_nhlt_endpoint_mic_count(const struct acpi_nhlt_endpoint *ep)
{ … }
EXPORT_SYMBOL_GPL(…);