u-boot/include/i2c.h

1 /* SPDX-License-Identifier: GPL-2.0+ */
4  * Copyright (C) 2009 - 2013 Heiko Schocher <hs@denx.de>
12  *   AIRVENT SAM s.p.a - RIMINI(ITALY)
20  * For now there are essentially two parts to this file - driver model
28 	DM_I2C_CHIP_10BIT	= 1 << 0, /* Use 10-bit addressing */
35  * struct dm_i2c_chip - information about an i2c chip
38  * and normally supports 7-bit or 10-bit addressing.
75  * struct dm_i2c_bus- information about an i2c bus
84  * @speed_hz: Bus speed in hertz (typically 100000)
91  * Not all of these flags are implemented in the U-Boot API
94 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
105  * struct i2c_msg - an I2C message
120  * struct i2c_msg_list - a list of I2C messages
123  * appropriate in U-Boot.
134  * dm_i2c_read() - read bytes from an I2C chip
148  * @return 0 on success, -ve on failure
153  * dm_i2c_write() - write bytes to an I2C chip
162  * @return 0 on success, -ve on failure
168  * dm_i2c_probe() - probe a particular chip address
175  * @chip_addr:	7-bit address to probe (10-bit and others are not supported)
178  * @return 0 if a chip was found at that address, -ve if not
184  * dm_i2c_reg_read() - Read a value from an I2C register
190  * @return value read, or -ve on error
195  * dm_i2c_reg_write() - Write a value to an I2C register
202  * @return 0 on success, -ve on error
207  * dm_i2c_xfer() - Transfer messages over I2C
215  * @return 0 on success, -ve on error
220  * dm_i2c_set_bus_speed() - set the speed of a bus
223  * @speed:	Requested speed in Hz
224  * @return 0 if OK, -EINVAL for invalid values
226 int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed);
229  * dm_i2c_get_bus_speed() - get the speed of a bus
232  * @return speed of selected I2C bus in Hz, -ve on error
237  * i2c_set_chip_flags() - set flags for a chip
239  * Typically addresses are 7 bits, but for 10-bit addresses you should set
240  * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing.
244  * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error
249  * i2c_get_chip_flags() - get flags for a chip
253  * @return 0 if OK, other -ve value on error
258  * i2c_set_offset_len() - set the offset length for a chip
270  * i2c_get_offset_len() - get the offset length for a chip
272  * @return:	Current offset length value (typically 1 or 2)
277  * i2c_set_chip_addr_offset_mask() - set mask of address bits usable by offset
284  * @return 0 if OK, other -ve value on error
289  * i2c_get_chip_addr_offset_mask() - get mask of address bits usable by offset
291  * @return current chip addr offset mask
296  * i2c_deblock() - recover a bus that is in an unknown state
301  * @return 0 if OK, -ve on error
307  * i2c_probe() - Compatibility function for driver model
309  * Calls dm_i2c_probe() on the current bus
314  * i2c_read() - Compatibility function for driver model
317  * set to @addr. @alen must match the current setting for the device.
323  * i2c_write() - Compatibility function for driver model
326  * set to @addr. @alen must match the current setting for the device.
332  * i2c_get_bus_num_fdt() - Compatibility function for driver model
339  * i2c_get_bus_num() - Compatibility function for driver model
341  * @return the 'current' bus number
346  * i2c_set_bus_num() - Compatibility function for driver model
348  * Sets the 'current' bus
363  * i2c_init() - Compatibility function for driver model
367 void i2c_init(int speed, int slaveaddr);
370  * board_i2c_init() - Compatibility function for driver model
386  * struct dm_i2c_ops - driver operations for I2C uclass
394 	 * xfer() - transfer a list of I2C messages
399 	 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte,
400 	 *	-ECOMM if the speed cannot be supported, -EPROTO if the chip
401 	 *	flags cannot be supported, other -ve value on some other error
406 	 * probe_chip() - probe for the presense of a chip address
414 	 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back
415 	 * to default probem other -ve value on error
420 	 * set_bus_speed() - set the speed of a bus (optional)
422 	 * The bus speed value will be updated by the uclass if this function
423 	 * does not return an error. This method is optional - if it is not
424 	 * provided then the driver can read the speed from
425 	 * dev_get_uclass_priv(bus)->speed_hz
428 	 * @speed:	Requested speed in Hz
429 	 * @return 0 if OK, -EINVAL for invalid values
431 	int (*set_bus_speed)(struct udevice *bus, unsigned int speed);
434 	 * get_bus_speed() - get the speed of a bus (optional)
437 	 * driver to check the bus speed by looking at the hardware, you can
439 	 * normally be expected to return dev_get_uclass_priv(bus)->speed_hz.
442 	 * @return speed of selected I2C bus in Hz, -ve on error
447 	 * set_flags() - set the flags for a chip (optional)
456 	 * @return 0 if OK, -EINVAL if value is unsupported
461 	 * deblock() - recover a bus that is in an unknown state
477 #define i2c_get_ops(dev)	((struct dm_i2c_ops *)(dev)->driver->ops)
480  * struct i2c_mux_ops - operations for an I2C mux
482  * The current mux state is expected to be stored in the mux itself since
484  * record the current state and then avoid switching unless it is necessary.
490 	 * select() - select one of of I2C buses attached to a mux
499 	 * @return 0 if OK, -ve on error
504 	 * deselect() - select one of of I2C buses attached to a mux
511 	 * @return 0 if OK, -ve on error
516 #define i2c_mux_get_ops(dev)	((struct i2c_mux_ops *)(dev)->driver->ops)
519  * i2c_get_chip() - get a device to use to access a chip on a bus
527  * @devp:	Returns pointer to new device if found or -ENODEV if not
534  * i2c_get_chip_for_busnum() - get a device to use to access a chip on
543  * @devp:	Returns pointer to new device if found or -ENODEV if not
550  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
563  * i2c_dump_msgs() - Dump a list of I2C messages
573  * i2c_emul_find() - Find an emulator for an i2c sandbox device
579  * @return 0 if OK, -ENOENT or -ENODEV if not found
584  * i2c_emul_get_device() - Find the device being emulated
601  * use of stack-based variables are OK (the initial stack size is
631 	void		(*init)(struct i2c_adapter *adap, int speed,
641 				uint speed);
642 	int		speed;  member
658 		.speed		=	_speed, \
689 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
696 #define	I2C_BUS			gd->cur_i2c_bus
699 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
700 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
737  * repeatedly to change the speed and slave addresses.
742 void i2c_init(int speed, int slaveaddr);
749  *  Returns index of currently active I2C bus.  Zero-based.
759  *	bus - bus index, zero based
771  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
809  *  Change the speed of the active I2C bus
811  *	speed - bus speed in Hz
813  *	Returns: new bus speed
816 unsigned int i2c_set_bus_speed(unsigned int speed);
821  *  Returns speed of currently active I2C bus in Hz
876  * Functions for setting the current I2C bus and its speed
885  *	bus - bus index, zero based
895  *  Returns index of currently active I2C bus.  Zero-based.
903  *  Change the speed of the active I2C bus
905  *	speed - bus speed in Hz
915  *  Returns speed of currently active I2C bus in Hz
968  * @return the number of I2C bus (zero based), or -1 on error
977  * @return 0 if port was reset, -1 if not found