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