linux/drivers/base/soc.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) ST-Ericsson SA 2011
 *
 * Author: Lee Jones <[email protected]> for ST-Ericsson.
 */

#include <linux/sysfs.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/idr.h>
#include <linux/spinlock.h>
#include <linux/sys_soc.h>
#include <linux/err.h>
#include <linux/glob.h>

static DEFINE_IDA(soc_ida);

/* Prototype to allow declarations of DEVICE_ATTR(<foo>) before soc_info_show */
static ssize_t soc_info_show(struct device *dev, struct device_attribute *attr,
			     char *buf);

struct soc_device { … };

static const struct bus_type soc_bus_type = …;
static bool soc_bus_registered;

static DEVICE_ATTR(machine,		0444, soc_info_show,  NULL);
static DEVICE_ATTR(family,		0444, soc_info_show,  NULL);
static DEVICE_ATTR(serial_number,	0444, soc_info_show,  NULL);
static DEVICE_ATTR(soc_id,		0444, soc_info_show,  NULL);
static DEVICE_ATTR(revision,		0444, soc_info_show,  NULL);

struct device *soc_device_to_device(struct soc_device *soc_dev)
{ … }

static umode_t soc_attribute_mode(struct kobject *kobj,
				struct attribute *attr,
				int index)
{ … }

static ssize_t soc_info_show(struct device *dev, struct device_attribute *attr,
			     char *buf)
{ … }

static struct attribute *soc_attr[] = …;

static const struct attribute_group soc_attr_group = …;

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

static void soc_device_get_machine(struct soc_device_attribute *soc_dev_attr)
{ … }

static struct soc_device_attribute *early_soc_dev_attr;

struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr)
{ … }
EXPORT_SYMBOL_GPL(…);

/* Ensure soc_dev->attr is freed after calling soc_device_unregister. */
void soc_device_unregister(struct soc_device *soc_dev)
{ … }
EXPORT_SYMBOL_GPL(…);

static int __init soc_bus_register(void)
{ … }
core_initcall(soc_bus_register);

static int soc_device_match_attr(const struct soc_device_attribute *attr,
				 const struct soc_device_attribute *match)
{ … }

static int soc_device_match_one(struct device *dev, void *arg)
{ … }

/*
 * soc_device_match - identify the SoC in the machine
 * @matches: zero-terminated array of possible matches
 *
 * returns the first matching entry of the argument array, or NULL
 * if none of them match.
 *
 * This function is meant as a helper in place of of_match_node()
 * in cases where either no device tree is available or the information
 * in a device node is insufficient to identify a particular variant
 * by its compatible strings or other properties. For new devices,
 * the DT binding should always provide unique compatible strings
 * that allow the use of of_match_node() instead.
 *
 * The calling function can use the .data entry of the
 * soc_device_attribute to pass a structure or function pointer for
 * each entry.
 */
const struct soc_device_attribute *soc_device_match(
	const struct soc_device_attribute *matches)
{ … }
EXPORT_SYMBOL_GPL(…);