diff options
Diffstat (limited to 'include/linux/i2c.h')
| -rw-r--r-- | include/linux/i2c.h | 84 |
1 files changed, 71 insertions, 13 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 65b4eaed1d96..be27062f8ed1 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -333,6 +333,7 @@ struct i2c_client { char name[I2C_NAME_SIZE]; struct i2c_adapter *adapter; /* the adapter we sit on */ struct device dev; /* the device structure */ + int init_irq; /* irq set at initialization */ int irq; /* irq issued by device */ struct list_head detected; #if IS_ENABLED(CONFIG_I2C_SLAVE) @@ -498,9 +499,13 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, * @master_xfer: Issue a set of i2c transactions to the given I2C adapter * defined by the msgs array, with num messages available to transfer via * the adapter specified by adap. + * @master_xfer_atomic: same as @master_xfer. Yet, only using atomic context + * so e.g. PMICs can be accessed very late before shutdown. Optional. * @smbus_xfer: Issue smbus transactions to the given I2C adapter. If this * is not present, then the bus layer will try and convert the SMBus calls * into I2C transfers instead. + * @smbus_xfer_atomic: same as @smbus_xfer. Yet, only using atomic context + * so e.g. PMICs can be accessed very late before shutdown. Optional. * @functionality: Return the flags that this algorithm/adapter pair supports * from the I2C_FUNC_* flags. * @reg_slave: Register given client to I2C slave mode of this adapter @@ -511,25 +516,33 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 * to name two of the most common. * - * The return codes from the @master_xfer field should indicate the type of - * error code that occurred during the transfer, as documented in the kernel - * Documentation file Documentation/i2c/fault-codes. + * The return codes from the @master_xfer{_atomic} fields should indicate the + * type of error code that occurred during the transfer, as documented in the + * Kernel Documentation file Documentation/i2c/fault-codes. */ struct i2c_algorithm { - /* If an adapter algorithm can't do I2C-level access, set master_xfer - to NULL. If an adapter algorithm can do SMBus access, set - smbus_xfer. If set to NULL, the SMBus protocol is simulated - using common I2C messages */ - /* master_xfer should return the number of messages successfully - processed, or a negative value on error */ + /* + * If an adapter algorithm can't do I2C-level access, set master_xfer + * to NULL. If an adapter algorithm can do SMBus access, set + * smbus_xfer. If set to NULL, the SMBus protocol is simulated + * using common I2C messages. + * + * master_xfer should return the number of messages successfully + * processed, or a negative value on error + */ int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); - int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, - unsigned short flags, char read_write, - u8 command, int size, union i2c_smbus_data *data); + int (*master_xfer_atomic)(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num); + int (*smbus_xfer)(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data); + int (*smbus_xfer_atomic)(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data); /* To determine what the adapter supports */ - u32 (*functionality) (struct i2c_adapter *); + u32 (*functionality)(struct i2c_adapter *adap); #if IS_ENABLED(CONFIG_I2C_SLAVE) int (*reg_slave)(struct i2c_client *client); @@ -680,6 +693,9 @@ struct i2c_adapter { int timeout; /* in jiffies */ int retries; struct device dev; /* the adapter device */ + unsigned long locked_flags; /* owned by the I2C core */ +#define I2C_ALF_IS_SUSPENDED 0 +#define I2C_ALF_SUSPEND_REPORTED 1 int nr; char name[48]; @@ -762,6 +778,38 @@ i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) adapter->lock_ops->unlock_bus(adapter, flags); } +/** + * i2c_mark_adapter_suspended - Report suspended state of the adapter to the core + * @adap: Adapter to mark as suspended + * + * When using this helper to mark an adapter as suspended, the core will reject + * further transfers to this adapter. The usage of this helper is optional but + * recommended for devices having distinct handlers for system suspend and + * runtime suspend. More complex devices are free to implement custom solutions + * to reject transfers when suspended. + */ +static inline void i2c_mark_adapter_suspended(struct i2c_adapter *adap) +{ + i2c_lock_bus(adap, I2C_LOCK_ROOT_ADAPTER); + set_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags); + i2c_unlock_bus(adap, I2C_LOCK_ROOT_ADAPTER); +} + +/** + * i2c_mark_adapter_resumed - Report resumed state of the adapter to the core + * @adap: Adapter to mark as resumed + * + * When using this helper to mark an adapter as resumed, the core will allow + * further transfers to this adapter. See also further notes to + * @i2c_mark_adapter_suspended(). + */ +static inline void i2c_mark_adapter_resumed(struct i2c_adapter *adap) +{ + i2c_lock_bus(adap, I2C_LOCK_ROOT_ADAPTER); + clear_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags); + i2c_unlock_bus(adap, I2C_LOCK_ROOT_ADAPTER); +} + /*flags for the client struct: */ #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ @@ -933,11 +981,21 @@ static inline int of_i2c_get_board_info(struct device *dev, #endif /* CONFIG_OF */ +struct acpi_resource; +struct acpi_resource_i2c_serialbus; + #if IS_ENABLED(CONFIG_ACPI) +bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, + struct acpi_resource_i2c_serialbus **i2c); u32 i2c_acpi_find_bus_speed(struct device *dev); struct i2c_client *i2c_acpi_new_device(struct device *dev, int index, struct i2c_board_info *info); #else +static inline bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, + struct acpi_resource_i2c_serialbus **i2c) +{ + return false; +} static inline u32 i2c_acpi_find_bus_speed(struct device *dev) { return 0; |