Branch data     Line data    Source code

       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 send
      27                 :            :  * the powerdown command to a PMIC. Atomic transfers are a corner case and not
      28                 :            :  * for generic use!
      29                 :            :  */
      30                 :          0 : static inline bool i2c_in_atomic_xfer_mode(void)
      31                 :            : {
      32   [ #  #  #  #  :          0 :         return system_state > SYSTEM_RUNNING && irqs_disabled();
             #  #  #  # ]
      33                 :            : }
      34                 :            : 
      35                 :          0 : static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
      36                 :            : {
      37                 :          0 :         int ret = 0;
      38                 :            : 
      39   [ #  #  #  # ]:          0 :         if (i2c_in_atomic_xfer_mode()) {
      40   [ #  #  #  #  :          0 :                 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         [ #  # ]:          0 :                 ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN;
      43                 :            :         } else {
      44                 :          0 :                 i2c_lock_bus(adap, I2C_LOCK_SEGMENT);
      45                 :            :         }
      46                 :            : 
      47                 :          0 :         return ret;
      48                 :            : }
      49                 :            : 
      50                 :          0 : static inline int __i2c_check_suspended(struct i2c_adapter *adap)
      51                 :            : {
      52         [ #  # ]:          0 :         if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) {
      53         [ #  # ]:          0 :                 if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags))
      54         [ #  # ]:          0 :                         dev_WARN(&adap->dev, "Transfer while suspended\n");
      55                 :          0 :                 return -ESHUTDOWN;
      56                 :            :         }
      57                 :            : 
      58                 :            :         return 0;
      59                 :            : }
      60                 :            : 
      61                 :            : #ifdef CONFIG_ACPI
      62                 :            : const struct acpi_device_id *
      63                 :            : i2c_acpi_match_device(const struct acpi_device_id *matches,
      64                 :            :                       struct i2c_client *client);
      65                 :            : void i2c_acpi_register_devices(struct i2c_adapter *adap);
      66                 :            : 
      67                 :            : int i2c_acpi_get_irq(struct i2c_client *client);
      68                 :            : #else /* CONFIG_ACPI */
      69                 :            : static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
      70                 :            : static inline const struct acpi_device_id *
      71                 :            : i2c_acpi_match_device(const struct acpi_device_id *matches,
      72                 :            :                       struct i2c_client *client)
      73                 :            : {
      74                 :            :         return NULL;
      75                 :            : }
      76                 :            : 
      77                 :            : static inline int i2c_acpi_get_irq(struct i2c_client *client)
      78                 :            : {
      79                 :            :         return 0;
      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                 :          0 : static inline void of_i2c_register_devices(struct i2c_adapter *adap) { }
      96                 :            : #endif
      97                 :            : extern struct notifier_block i2c_of_notifier;