linux/drivers/soundwire/master.c

// SPDX-License-Identifier: GPL-2.0-only
// Copyright(c) 2019-2020 Intel Corporation.

#include <linux/device.h>
#include <linux/acpi.h>
#include <linux/pm_runtime.h>
#include <linux/soundwire/sdw.h>
#include <linux/soundwire/sdw_type.h>
#include "bus.h"

/*
 * The 3s value for autosuspend will only be used if there are no
 * devices physically attached on a bus segment. In practice enabling
 * the bus operation will result in children devices become active and
 * the master device will only suspend when all its children are no
 * longer active.
 */
#define SDW_MASTER_SUSPEND_DELAY_MS …

/*
 * The sysfs for properties reflects the MIPI description as given
 * in the MIPI DisCo spec
 *
 * Base file is:
 *	sdw-master-N
 *      |---- revision
 *      |---- clk_stop_modes
 *      |---- max_clk_freq
 *      |---- clk_freq
 *      |---- clk_gears
 *      |---- default_row
 *      |---- default_col
 *      |---- dynamic_shape
 *      |---- err_threshold
 */

#define sdw_master_attr(field, format_string) …

sdw_master_attr(…);
sdw_master_attr(…);
sdw_master_attr(…);
sdw_master_attr(…);
sdw_master_attr(…);
sdw_master_attr(…);
sdw_master_attr(…);
sdw_master_attr(…);

static ssize_t clock_frequencies_show(struct device *dev,
				      struct device_attribute *attr, char *buf)
{ … }
static DEVICE_ATTR_RO(clock_frequencies);

static ssize_t clock_gears_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{ … }
static DEVICE_ATTR_RO(clock_gears);

static struct attribute *master_node_attrs[] = …;
ATTRIBUTE_GROUPS(…);

static void sdw_master_device_release(struct device *dev)
{ … }

static const struct dev_pm_ops master_dev_pm = …;

const struct device_type sdw_master_type = …;

/**
 * sdw_master_device_add() - create a Linux Master Device representation.
 * @bus: SDW bus instance
 * @parent: parent device
 * @fwnode: firmware node handle
 */
int sdw_master_device_add(struct sdw_bus *bus, struct device *parent,
			  struct fwnode_handle *fwnode)
{ … }

/**
 * sdw_master_device_del() - delete a Linux Master Device representation.
 * @bus: bus handle
 *
 * This function is the dual of sdw_master_device_add()
 */
int sdw_master_device_del(struct sdw_bus *bus)
{ … }