1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-or-later */ 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * i2c-core.h - interfaces internal to the I2C framework 4*4882a593Smuzhiyun */ 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun #include <linux/rwsem.h> 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun struct i2c_devinfo { 9*4882a593Smuzhiyun struct list_head list; 10*4882a593Smuzhiyun int busnum; 11*4882a593Smuzhiyun struct i2c_board_info board_info; 12*4882a593Smuzhiyun }; 13*4882a593Smuzhiyun 14*4882a593Smuzhiyun /* board_lock protects board_list and first_dynamic_bus_num. 15*4882a593Smuzhiyun * only i2c core components are allowed to use these symbols. 16*4882a593Smuzhiyun */ 17*4882a593Smuzhiyun extern struct rw_semaphore __i2c_board_lock; 18*4882a593Smuzhiyun extern struct list_head __i2c_board_list; 19*4882a593Smuzhiyun extern int __i2c_first_dynamic_bus_num; 20*4882a593Smuzhiyun 21*4882a593Smuzhiyun int i2c_check_7bit_addr_validity_strict(unsigned short addr); 22*4882a593Smuzhiyun int i2c_dev_irq_from_resources(const struct resource *resources, 23*4882a593Smuzhiyun unsigned int num_resources); 24*4882a593Smuzhiyun 25*4882a593Smuzhiyun /* 26*4882a593Smuzhiyun * We only allow atomic transfers for very late communication, e.g. to access a 27*4882a593Smuzhiyun * PMIC when powering down. Atomic transfers are a corner case and not for 28*4882a593Smuzhiyun * generic use! 29*4882a593Smuzhiyun */ i2c_in_atomic_xfer_mode(void)30*4882a593Smuzhiyunstatic inline bool i2c_in_atomic_xfer_mode(void) 31*4882a593Smuzhiyun { 32*4882a593Smuzhiyun return system_state > SYSTEM_RUNNING && irqs_disabled(); 33*4882a593Smuzhiyun } 34*4882a593Smuzhiyun __i2c_lock_bus_helper(struct i2c_adapter * adap)35*4882a593Smuzhiyunstatic inline int __i2c_lock_bus_helper(struct i2c_adapter *adap) 36*4882a593Smuzhiyun { 37*4882a593Smuzhiyun int ret = 0; 38*4882a593Smuzhiyun 39*4882a593Smuzhiyun if (i2c_in_atomic_xfer_mode()) { 40*4882a593Smuzhiyun WARN(!adap->algo->master_xfer_atomic && !adap->algo->smbus_xfer_atomic, 41*4882a593Smuzhiyun "No atomic I2C transfer handler for '%s'\n", dev_name(&adap->dev)); 42*4882a593Smuzhiyun ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN; 43*4882a593Smuzhiyun } else { 44*4882a593Smuzhiyun i2c_lock_bus(adap, I2C_LOCK_SEGMENT); 45*4882a593Smuzhiyun } 46*4882a593Smuzhiyun 47*4882a593Smuzhiyun return ret; 48*4882a593Smuzhiyun } 49*4882a593Smuzhiyun __i2c_check_suspended(struct i2c_adapter * adap)50*4882a593Smuzhiyunstatic inline int __i2c_check_suspended(struct i2c_adapter *adap) 51*4882a593Smuzhiyun { 52*4882a593Smuzhiyun if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) { 53*4882a593Smuzhiyun if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags)) 54*4882a593Smuzhiyun dev_WARN(&adap->dev, "Transfer while suspended\n"); 55*4882a593Smuzhiyun return -ESHUTDOWN; 56*4882a593Smuzhiyun } 57*4882a593Smuzhiyun 58*4882a593Smuzhiyun return 0; 59*4882a593Smuzhiyun } 60*4882a593Smuzhiyun 61*4882a593Smuzhiyun #ifdef CONFIG_ACPI 62*4882a593Smuzhiyun void i2c_acpi_register_devices(struct i2c_adapter *adap); 63*4882a593Smuzhiyun 64*4882a593Smuzhiyun int i2c_acpi_get_irq(struct i2c_client *client); 65*4882a593Smuzhiyun #else /* CONFIG_ACPI */ i2c_acpi_register_devices(struct i2c_adapter * adap)66*4882a593Smuzhiyunstatic inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { } 67*4882a593Smuzhiyun i2c_acpi_get_irq(struct i2c_client * client)68*4882a593Smuzhiyunstatic inline int i2c_acpi_get_irq(struct i2c_client *client) 69*4882a593Smuzhiyun { 70*4882a593Smuzhiyun return 0; 71*4882a593Smuzhiyun } 72*4882a593Smuzhiyun #endif /* CONFIG_ACPI */ 73*4882a593Smuzhiyun extern struct notifier_block i2c_acpi_notifier; 74*4882a593Smuzhiyun 75*4882a593Smuzhiyun #ifdef CONFIG_ACPI_I2C_OPREGION 76*4882a593Smuzhiyun int i2c_acpi_install_space_handler(struct i2c_adapter *adapter); 77*4882a593Smuzhiyun void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter); 78*4882a593Smuzhiyun #else /* CONFIG_ACPI_I2C_OPREGION */ i2c_acpi_install_space_handler(struct i2c_adapter * adapter)79*4882a593Smuzhiyunstatic inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; } i2c_acpi_remove_space_handler(struct i2c_adapter * adapter)80*4882a593Smuzhiyunstatic inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { } 81*4882a593Smuzhiyun #endif /* CONFIG_ACPI_I2C_OPREGION */ 82*4882a593Smuzhiyun 83*4882a593Smuzhiyun #ifdef CONFIG_OF 84*4882a593Smuzhiyun void of_i2c_register_devices(struct i2c_adapter *adap); 85*4882a593Smuzhiyun #else of_i2c_register_devices(struct i2c_adapter * adap)86*4882a593Smuzhiyunstatic inline void of_i2c_register_devices(struct i2c_adapter *adap) { } 87*4882a593Smuzhiyun #endif 88*4882a593Smuzhiyun extern struct notifier_block i2c_of_notifier; 89