1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * i2c-core.h - interfaces internal to the I2C framework
 
 
 
 
 
 
 
 
 
 
 4 */
 5
 6#include <linux/kconfig.h>
 7#include <linux/rwsem.h>
 8
 9struct i2c_devinfo {
10	struct list_head	list;
11	int			busnum;
12	struct i2c_board_info	board_info;
13};
14
15/* board_lock protects board_list and first_dynamic_bus_num.
16 * only i2c core components are allowed to use these symbols.
17 */
18extern struct rw_semaphore	__i2c_board_lock;
19extern struct list_head	__i2c_board_list;
20extern int		__i2c_first_dynamic_bus_num;
21
22int i2c_check_7bit_addr_validity_strict(unsigned short addr);
23int i2c_dev_irq_from_resources(const struct resource *resources,
24			       unsigned int num_resources);
25
26/*
27 * We only allow atomic transfers for very late communication, e.g. to access a
28 * PMIC when powering down. Atomic transfers are a corner case and not for
29 * generic use!
30 */
31static inline bool i2c_in_atomic_xfer_mode(void)
32{
33	return system_state > SYSTEM_RUNNING &&
34	       (IS_ENABLED(CONFIG_PREEMPT_COUNT) ? !preemptible() : irqs_disabled());
35}
36
37static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
38{
39	int ret = 0;
40
41	if (i2c_in_atomic_xfer_mode()) {
42		WARN(!adap->algo->master_xfer_atomic && !adap->algo->smbus_xfer_atomic,
43		     "No atomic I2C transfer handler for '%s'\n", dev_name(&adap->dev));
44		ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN;
45	} else {
46		i2c_lock_bus(adap, I2C_LOCK_SEGMENT);
47	}
48
49	return ret;
50}
51
52static inline int __i2c_check_suspended(struct i2c_adapter *adap)
53{
54	if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) {
55		if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags))
56			dev_WARN(&adap->dev, "Transfer while suspended\n");
57		return -ESHUTDOWN;
58	}
59
60	return 0;
61}
62
63#ifdef CONFIG_ACPI
 
 
 
64void i2c_acpi_register_devices(struct i2c_adapter *adap);
65
66int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable);
67#else /* CONFIG_ACPI */
68static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
69
70static inline int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
 
71{
72	return 0;
73}
74#endif /* CONFIG_ACPI */
75extern struct notifier_block i2c_acpi_notifier;
76
77#ifdef CONFIG_ACPI_I2C_OPREGION
78int i2c_acpi_install_space_handler(struct i2c_adapter *adapter);
79void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter);
80#else /* CONFIG_ACPI_I2C_OPREGION */
81static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; }
82static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { }
83#endif /* CONFIG_ACPI_I2C_OPREGION */
84
85#ifdef CONFIG_OF
86void of_i2c_register_devices(struct i2c_adapter *adap);
87#else
88static inline void of_i2c_register_devices(struct i2c_adapter *adap) { }
89#endif
90extern struct notifier_block i2c_of_notifier;
91
92#if IS_ENABLED(CONFIG_I2C_SMBUS)
93int i2c_setup_smbus_alert(struct i2c_adapter *adap);
94#else
95static inline int i2c_setup_smbus_alert(struct i2c_adapter *adap)
96{
97	return 0;
98}
99#endif

 
 1/*
 2 * i2c-core.h - interfaces internal to the I2C framework
 3 *
 4 * This program is free software; you can redistribute it and/or modify
 5 * it under the terms of the GNU General Public License as published by
 6 * the Free Software Foundation; either version 2 of the License, or
 7 * (at your option) any later version.
 8 *
 9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 */
14
 
15#include <linux/rwsem.h>
16
17struct i2c_devinfo {
18	struct list_head	list;
19	int			busnum;
20	struct i2c_board_info	board_info;
21};
22
23/* board_lock protects board_list and first_dynamic_bus_num.
24 * only i2c core components are allowed to use these symbols.
25 */
26extern struct rw_semaphore	__i2c_board_lock;
27extern struct list_head	__i2c_board_list;
28extern int		__i2c_first_dynamic_bus_num;
29
30int i2c_check_7bit_addr_validity_strict(unsigned short addr);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
31
32#ifdef CONFIG_ACPI
33const struct acpi_device_id *
34i2c_acpi_match_device(const struct acpi_device_id *matches,
35		      struct i2c_client *client);
36void i2c_acpi_register_devices(struct i2c_adapter *adap);
 
 
37#else /* CONFIG_ACPI */
38static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
39static inline const struct acpi_device_id *
40i2c_acpi_match_device(const struct acpi_device_id *matches,
41		      struct i2c_client *client)
42{
43	return NULL;
44}
45#endif /* CONFIG_ACPI */
46extern struct notifier_block i2c_acpi_notifier;
47
48#ifdef CONFIG_ACPI_I2C_OPREGION
49int i2c_acpi_install_space_handler(struct i2c_adapter *adapter);
50void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter);
51#else /* CONFIG_ACPI_I2C_OPREGION */
52static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; }
53static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { }
54#endif /* CONFIG_ACPI_I2C_OPREGION */
55
56#ifdef CONFIG_OF
57void of_i2c_register_devices(struct i2c_adapter *adap);
58#else
59static inline void of_i2c_register_devices(struct i2c_adapter *adap) { }
60#endif
61extern struct notifier_block i2c_of_notifier;