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
37  * An I2C chip is a device on the I2C bus. It sits at a particular address
38  * and normally supports 7-bit or 10-bit addressing.
41  * the chip to examine.
43  * @chip_addr:	Chip address on bus
47  * @flags:	Flags for this chip (dm_i2c_chip_flags)
51  *			   completely within the chip address itself.
52  *			   e.g. a devce with chip address of 0x2c with 512
56  *			   This means it will respond to  chip address 0x2c and
61  * @emul: Emulator for this chip address (only used for emulation)
75  * struct dm_i2c_bus- information about an i2c bus
77  * An I2C bus contains 0 or more chips on it, each at its own address. The
91  * Not all of these flags are implemented in the U-Boot API
94 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
100 	I2C_M_NO_RD_ACK		= 0x0800, /* skip the Ack bit on reads */
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
136  * To obtain an I2C device (called a 'chip') given the I2C bus address you
143  * @dev:	Chip to read from
144  * @offset:	Offset within chip to start reading
148  * @return 0 on success, -ve on failure
153  * dm_i2c_write() - write bytes to an I2C chip
157  * @dev:	Chip to write to
158  * @offset:	Offset within chip to start writing
162  * @return 0 on success, -ve on failure
168  * dm_i2c_probe() - probe a particular chip address
170  * This can be useful to check for the existence of a chip on the bus.
171  * It is typically implemented by writing the chip address to the bus
172  * and checking that the chip replies with an ACK.
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
186  * This reads a single value from the given address in an I2C chip
190  * @return value read, or -ve on error
195  * dm_i2c_reg_write() - Write a value to an I2C register
197  * This writes a single value to the given address in an I2C chip
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
224  * @return 0 if OK, -EINVAL for invalid values
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.
242  * @dev:	Chip to adjust
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
251  * @dev:	Chip to check
253  * @return 0 if OK, other -ve value on error
258  * i2c_set_offset_len() - set the offset length for a chip
260  * The offset used to access a chip may be up to 4 bytes long. Typically it
270  * i2c_get_offset_len() - get the offset length for a chip
277  * i2c_set_chip_addr_offset_mask() - set mask of address bits usable by offset
279  * Some devices listen on multiple chip addresses to achieve larger offsets
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
323  * i2c_write() - Compatibility function for driver model
332  * i2c_get_bus_num_fdt() - Compatibility function for driver model
339  * i2c_get_bus_num() - Compatibility function for driver model
346  * i2c_set_bus_num() - Compatibility function for driver model
363  * i2c_init() - Compatibility function for driver model
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
412 	 * @chip_addr:	Chip address to probe
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)
423 	 * does not return an error. This method is optional - if it is not
425 	 * dev_get_uclass_priv(bus)->speed_hz
429 	 * @return 0 if OK, -EINVAL for invalid values
434 	 * get_bus_speed() - get the speed of a bus (optional)
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)
454 	 * @dev:	Chip to adjust
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
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
521  * This returns the device for the given chip address. The device can then
525  * @chip_addr:	Chip address for the new device
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
537  * This returns the device for the given chip address on a particular bus
541  * @chip_addr:	Chip address for the new device
543  * @devp:	Returns pointer to new device if found or -ENODEV if not
550  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
552  * This decodes the chip address from a device tree node and puts it into
560 int i2c_chip_ofdata_to_platdata(struct udevice *dev, struct dm_i2c_chip *chip);
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
633 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
634 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
637 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
681 	uint8_t		chip;  member
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)
736  * Initialization, must be called once on start up, may be called
749  *  Returns index of currently active I2C bus.  Zero-based.
759  *	bus - bus index, zero based
761  *	Returns: 0 on success, not 0 on failure
771  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
776  * Probe the given I2C chip address.  Returns 0 if a chip responded,
777  * not 0 on failure.
779 int i2c_probe(uint8_t chip);
783  *   chip:    I2C chip address, range 0..127
784  *   addr:    Memory (register) address within the chip
791  *   Returns: 0 on success, not 0 on failure
793 int i2c_read(uint8_t chip, unsigned int addr, int alen,
796 int i2c_write(uint8_t chip, unsigned int addr, int alen,
811  *	speed - bus speed in Hz
829  * Probe the given I2C chip address.  Returns 0 if a chip responded,
830  * not 0 on failure.
832 int i2c_probe(uchar chip);
836  *   chip:    I2C chip address, range 0..127
837  *   addr:    Memory (register) address within the chip
844  *   Returns: 0 on success, not 0 on failure
846 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
847 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
885  *	bus - bus index, zero based
887  *	Returns: 0 on success, not 0 on failure
895  *  Returns index of currently active I2C bus.  Zero-based.
905  *	speed - bus speed in Hz
907  *	Returns: 0 on success, not 0 on failure
968  * @return the number of I2C bus (zero based), or -1 on error
977  * @return 0 if port was reset, -1 if not found