linux/drivers/soc/qcom/smem_state.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2015, Sony Mobile Communications Inc.
 * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
 */
#include <linux/device.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/soc/qcom/smem_state.h>

static LIST_HEAD(smem_states);
static DEFINE_MUTEX(list_lock);

/**
 * struct qcom_smem_state - state context
 * @refcount:	refcount for the state
 * @orphan:	boolean indicator that this state has been unregistered
 * @list:	entry in smem_states list
 * @of_node:	of_node to use for matching the state in DT
 * @priv:	implementation private data
 * @ops:	ops for the state
 */
struct qcom_smem_state { … };

/**
 * qcom_smem_state_update_bits() - update the masked bits in state with value
 * @state:	state handle acquired by calling qcom_smem_state_get()
 * @mask:	bit mask for the change
 * @value:	new value for the masked bits
 *
 * Returns 0 on success, otherwise negative errno.
 */
int qcom_smem_state_update_bits(struct qcom_smem_state *state,
				u32 mask,
				u32 value)
{ … }
EXPORT_SYMBOL_GPL(…);

static struct qcom_smem_state *of_node_to_state(struct device_node *np)
{ … }

/**
 * qcom_smem_state_get() - acquire handle to a state
 * @dev:	client device pointer
 * @con_id:	name of the state to lookup
 * @bit:	flags from the state reference, indicating which bit's affected
 *
 * Returns handle to the state, or ERR_PTR(). qcom_smem_state_put() must be
 * called to release the returned state handle.
 */
struct qcom_smem_state *qcom_smem_state_get(struct device *dev,
					    const char *con_id,
					    unsigned *bit)
{ … }
EXPORT_SYMBOL_GPL(…);

static void qcom_smem_state_release(struct kref *ref)
{ … }

/**
 * qcom_smem_state_put() - release state handle
 * @state:	state handle to be released
 */
void qcom_smem_state_put(struct qcom_smem_state *state)
{ … }
EXPORT_SYMBOL_GPL(…);

static void devm_qcom_smem_state_release(struct device *dev, void *res)
{ … }

/**
 * devm_qcom_smem_state_get() - acquire handle to a devres managed state
 * @dev:	client device pointer
 * @con_id:	name of the state to lookup
 * @bit:	flags from the state reference, indicating which bit's affected
 *
 * Returns handle to the state, or ERR_PTR(). qcom_smem_state_put() is called
 * automatically when @dev is removed.
 */
struct qcom_smem_state *devm_qcom_smem_state_get(struct device *dev,
						 const char *con_id,
						 unsigned *bit)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * qcom_smem_state_register() - register a new state
 * @of_node:	of_node used for matching client lookups
 * @ops:	implementation ops
 * @priv:	implementation specific private data
 */
struct qcom_smem_state *qcom_smem_state_register(struct device_node *of_node,
						 const struct qcom_smem_state_ops *ops,
						 void *priv)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * qcom_smem_state_unregister() - unregister a registered state
 * @state:	state handle to be unregistered
 */
void qcom_smem_state_unregister(struct qcom_smem_state *state)
{ … }
EXPORT_SYMBOL_GPL(…);