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 17 struct 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 */ 26 extern struct rw_semaphore __i2c_board_lock; 27 extern struct list_head __i2c_board_list; 28 extern int __i2c_first_dynamic_bus_num; 29 30 int i2c_check_7bit_addr_validity_strict(unsigned short addr); 31 32 /* 33 * We only allow atomic transfers for very late communication, e.g. to send 34 * the powerdown command to a PMIC. Atomic transfers are a corner case and not 35 * for generic use! 36 */ 37 static inline bool i2c_in_atomic_xfer_mode(void) 38 { 39 return system_state > SYSTEM_RUNNING && irqs_disabled(); 40 } 41 42 static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap) 43 { 44 int ret = 0; 45 46 if (i2c_in_atomic_xfer_mode()) { 47 WARN(!adap->algo->master_xfer_atomic && !adap->algo->smbus_xfer_atomic, 48 "No atomic I2C transfer handler for '%s'\n", dev_name(&adap->dev)); 49 ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN; 50 } else { 51 i2c_lock_bus(adap, I2C_LOCK_SEGMENT); 52 } 53 54 return ret; 55 } 56 57 static inline int __i2c_check_suspended(struct i2c_adapter *adap) 58 { 59 if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) { 60 if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags)) 61 dev_WARN(&adap->dev, "Transfer while suspended\n"); 62 return -ESHUTDOWN; 63 } 64 65 return 0; 66 } 67 68 #ifdef CONFIG_ACPI 69 const struct acpi_device_id * 70 i2c_acpi_match_device(const struct acpi_device_id *matches, 71 struct i2c_client *client); 72 void i2c_acpi_register_devices(struct i2c_adapter *adap); 73 #else /* CONFIG_ACPI */ 74 static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { } 75 static inline const struct acpi_device_id * 76 i2c_acpi_match_device(const struct acpi_device_id *matches, 77 struct i2c_client *client) 78 { 79 return NULL; 80 } 81 #endif /* CONFIG_ACPI */ 82 extern struct notifier_block i2c_acpi_notifier; 83 84 #ifdef CONFIG_ACPI_I2C_OPREGION 85 int i2c_acpi_install_space_handler(struct i2c_adapter *adapter); 86 void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter); 87 #else /* CONFIG_ACPI_I2C_OPREGION */ 88 static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; } 89 static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { } 90 #endif /* CONFIG_ACPI_I2C_OPREGION */ 91 92 #ifdef CONFIG_OF 93 void of_i2c_register_devices(struct i2c_adapter *adap); 94 #else 95 static inline void of_i2c_register_devices(struct i2c_adapter *adap) { } 96 #endif 97 extern struct notifier_block i2c_of_notifier; 98