include/linux/i2c.h

1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3  * i2c.h - definitions for the Linux i2c bus interface
4  * Copyright (C) 1995-2000 Simon G. Vogl
5  * Copyright (C) 2013-2019 Wolfram Sang <wsa@kernel.org>
30 /* --- General options ------------------------------------------------	*/
69  * i2c_master_recv - issue a single I2C message in master receive mode
83  * i2c_master_recv_dmasafe - issue a single I2C message in master receive mode
99  * i2c_master_send - issue a single I2C message in master transmit mode
113  * i2c_master_send_dmasafe - issue a single I2C message in master transmit mode
195  * struct i2c_device_identity - i2c client device identification
196  * @manufacturer_id: 0 - 4095, database maintained by NXP
197  * @part_id: 0 - 511, according to manufacturer
198  * @die_revision: 0 - 7, according to manufacturer
227  * enum i2c_driver_flags - Flags for an I2C device driver
236  * struct i2c_driver - represent an I2C device driver
242  * @command: Callback for bus-wide signaling (optional)
247  * @clients: List of detected clients we created (for i2c-core use only)
286 	 * 16-bit payload data reported by the slave device acting as master.
309  * struct i2c_client - represent an I2C slave device
313  *	generic enough to hide second-sourcing and compatible revisions.
318  * @detected: member of an i2c_driver.clients list or i2c-core's
340 	unsigned short addr;		/* chip address - NOTE: 7bit	*/
370 	return dev_get_drvdata(&client->dev);  in i2c_get_clientdata()
375 	dev_set_drvdata(&client->dev, data);  in i2c_set_clientdata()
399  * struct i2c_board_info - template for device creation
403  * @dev_name: Overrides the default <busnr>-<addr> dev_name if set
420  * bus numbers identify adapters that aren't yet available.  For add-on boards,
438  * I2C_BOARD_INFO - macro used to list an i2c device and its address
444  * fields (such as associated irq, or device-specific platform_data)
453  * Add-on boards should register/unregister their devices; e.g. a board
454  * with integrated I2C, a config eeprom, sensors, and a codec that's
498  * Modules for add-on boards must use other calls.
514  * struct i2c_algorithm - represent I2C transfer methods
535  * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
540  * Kernel Documentation file Documentation/i2c/fault-codes.rst. Otherwise, the
545 	 * If an adapter algorithm can't do I2C-level access, set xfer
585  * struct i2c_lock_operations - represent I2C locking operations
599  * struct i2c_timings - I2C timing information
623  * struct i2c_bus_recovery_info - I2C bus recovery information
679  * struct i2c_adapter_quirks - describe flaws of an i2c adapter
684  * @max_comb_1st_msg_len: maximum length of the first msg in a combined message
685  * @max_comb_2nd_msg_len: maximum length of the second msg in a combined message
687  * Note about combined messages: Some I2C controllers can only send one message
688  * per transfer, plus something called combined message or write-then-read.
692  * with max_comb_*_len because combined message mode usually has its own
694  * write-then-anything or other variants. To support that, write-then-read has
695  * been broken out into smaller bits like write-first and read-second which can
696  * be combined as needed.
710 /* first combined message must be write */
712 /* second combined message must be read */
714 /* both combined messages must have the same target address */
716 /* convenience macro for typical write-then read case */
772 	return dev_get_drvdata(&adap->dev);  in i2c_get_adapdata()
777 	dev_set_drvdata(&adap->dev, data);  in i2c_set_adapdata()
784 	struct device *parent = adapter->dev.parent;  in i2c_parent_is_i2c_adapter()
786 	if (parent != NULL && parent->type == &i2c_adapter_type)  in i2c_parent_is_i2c_adapter()
800  * i2c_lock_bus - Get exclusive access to an I2C bus segment
808 	adapter->lock_ops->lock_bus(adapter, flags);  in i2c_lock_bus()
812  * i2c_trylock_bus - Try to get exclusive access to an I2C bus segment
822 	return adapter->lock_ops->trylock_bus(adapter, flags);  in i2c_trylock_bus()
826  * i2c_unlock_bus - Release exclusive access to an I2C bus segment
834 	adapter->lock_ops->unlock_bus(adapter, flags);  in i2c_unlock_bus()
838  * i2c_mark_adapter_suspended - Report suspended state of the adapter to the core
850 	set_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags);  in i2c_mark_adapter_suspended()
855  * i2c_mark_adapter_resumed - Report resumed state of the adapter to the core
865 	clear_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags);  in i2c_mark_adapter_resumed()
877 /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
882 /* ----- functions exported by i2c.o */
901 	return !IS_ERR_OR_NULL(client) && client->dev.driver;  in i2c_client_has_driver()
904 /* call the i2c_client->command() of all attached clients with
918 	return adap->algo->functionality(adap);  in i2c_get_functionality()
928  * i2c_check_quirks() - Function for checking the quirk flags in an i2c adapter
936 	if (!adap->quirks)  in i2c_check_quirks()
938 	return (adap->quirks->flags & quirks) == quirks;  in i2c_check_quirks()
944 	return adap->nr;  in i2c_adapter_id()
949 	return (msg->addr << 1) | (msg->flags & I2C_M_RD);  in i2c_8bit_addr_from_msg()
957  * module_i2c_driver() - Helper macro for registering a modular I2C driver
969  * builtin_i2c_driver() - Helper macro for registering a builtin I2C driver
1064 	return -ENOTSUPP;  in of_i2c_get_board_info()
1100 	return ERR_PTR(-ENODEV);  in i2c_acpi_new_device_by_fwnode()