u-boot/include/i2c.h

3  * Copyright (C) 2009 - 2013 Heiko Schocher <hs@denx.de>
9  * SPDX-License-Identifier:	GPL-2.0+
13  *   AIRVENT SAM s.p.a - RIMINI(ITALY)
21  * For now there are essentially two parts to this file - driver model
29 	DM_I2C_CHIP_10BIT	= 1 << 0, /* Use 10-bit addressing */
36  * struct dm_i2c_chip - information about an i2c chip
38  * An I2C chip is a device on the I2C bus. It sits at a particular address
39  * and normally supports 7-bit or 10-bit addressing.
42  * the chip to examine.
44  * @chip_addr:	Chip address on bus
48  * @flags:	Flags for this chip (dm_i2c_chip_flags)
49  * @emul: Emulator for this chip address (only used for emulation)
62  * struct dm_i2c_bus- information about an i2c bus
64  * An I2C bus contains 0 or more chips on it, each at its own address. The
78  * Not all of these flags are implemented in the U-Boot API
81 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
87 	I2C_M_NO_RD_ACK		= 0x0800, /* skip the Ack bit on reads */
92  * struct i2c_msg - an I2C message
107  * struct i2c_msg_list - a list of I2C messages
110  * appropriate in U-Boot.
121  * dm_i2c_read() - read bytes from an I2C chip
123  * To obtain an I2C device (called a 'chip') given the I2C bus address you
130  * @dev:	Chip to read from
131  * @offset:	Offset within chip to start reading
135  * @return 0 on success, -ve on failure
140  * dm_i2c_write() - write bytes to an I2C chip
144  * @dev:	Chip to write to
145  * @offset:	Offset within chip to start writing
149  * @return 0 on success, -ve on failure
155  * dm_i2c_probe() - probe a particular chip address
157  * This can be useful to check for the existence of a chip on the bus.
158  * It is typically implemented by writing the chip address to the bus
159  * and checking that the chip replies with an ACK.
162  * @chip_addr:	7-bit address to probe (10-bit and others are not supported)
165  * @return 0 if a chip was found at that address, -ve if not
171  * dm_i2c_reg_read() - Read a value from an I2C register
173  * This reads a single value from the given address in an I2C chip
177  * @return value read, or -ve on error
182  * dm_i2c_reg_write() - Write a value to an I2C register
184  * This writes a single value to the given address in an I2C chip
189  * @return 0 on success, -ve on error
194  * dm_i2c_reg_clrset() - Apply bitmask to an I2C register
197  * given address in an I2C chip
203  * @return 0 on success, -ve on error
208  * dm_i2c_xfer() - Transfer messages over I2C
216  * @return 0 on success, -ve on error
221  * dm_i2c_set_bus_speed() - set the speed of a bus
225  * @return 0 if OK, -EINVAL for invalid values
230  * dm_i2c_get_bus_speed() - get the speed of a bus
233  * @return speed of selected I2C bus in Hz, -ve on error
238  * i2c_set_chip_flags() - set flags for a chip
240  * Typically addresses are 7 bits, but for 10-bit addresses you should set
241  * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing.
243  * @dev:	Chip to adjust
245  * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error
250  * i2c_get_chip_flags() - get flags for a chip
252  * @dev:	Chip to check
254  * @return 0 if OK, other -ve value on error
259  * i2c_set_offset_len() - set the offset length for a chip
261  * The offset used to access a chip may be up to 4 bytes long. Typically it
271  * i2c_get_offset_len() - get the offset length for a chip
278  * i2c_deblock() - recover a bus that is in an unknown state
283  * @return 0 if OK, -ve on error
289  * i2c_probe() - Compatibility function for driver model
291  * Calls dm_i2c_probe() on the current bus
296  * i2c_read() - Compatibility function for driver model
305  * i2c_write() - Compatibility function for driver model
314  * i2c_get_bus_num_fdt() - Compatibility function for driver model
321  * i2c_get_bus_num() - Compatibility function for driver model
328  * i2c_set_bus_num() - Compatibility function for driver model
345  * i2c_init() - Compatibility function for driver model
352  * board_i2c_init() - Compatibility function for driver model
368  * struct dm_i2c_ops - driver operations for I2C uclass
376 	 * xfer() - transfer a list of I2C messages
381 	 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte,
382 	 *	-ECOMM if the speed cannot be supported, -EPROTO if the chip
383 	 *	flags cannot be supported, other -ve value on some other error
388 	 * probe_chip() - probe for the presense of a chip address
394 	 * @chip_addr:	Chip address to probe
396 	 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back
397 	 * to default probem other -ve value on error
402 	 * set_bus_speed() - set the speed of a bus (optional)
405 	 * does not return an error. This method is optional - if it is not
407 	 * dev_get_uclass_priv(bus)->speed_hz
411 	 * @return 0 if OK, -EINVAL for invalid values
416 	 * get_bus_speed() - get the speed of a bus (optional)
421 	 * normally be expected to return dev_get_uclass_priv(bus)->speed_hz.
424 	 * @return speed of selected I2C bus in Hz, -ve on error
429 	 * set_flags() - set the flags for a chip (optional)
436 	 * @dev:	Chip to adjust
438 	 * @return 0 if OK, -EINVAL if value is unsupported
443 	 * deblock() - recover a bus that is in an unknown state
459 #define i2c_get_ops(dev)	((struct dm_i2c_ops *)(dev)->driver->ops)
462  * struct i2c_mux_ops - operations for an I2C mux
472 	 * select() - select one of of I2C buses attached to a mux
481 	 * @return 0 if OK, -ve on error
486 	 * deselect() - select one of of I2C buses attached to a mux
493 	 * @return 0 if OK, -ve on error
498 #define i2c_mux_get_ops(dev)	((struct i2c_mux_ops *)(dev)->driver->ops)
501  * i2c_get_chip() - get a device to use to access a chip on a bus
503  * This returns the device for the given chip address. The device can then
507  * @chip_addr:	Chip address for the new device
509  * @devp:	Returns pointer to new device if found or -ENODEV if not
516  * i2c_get_chip_for_busnum() - get a device to use to access a chip on
519  * This returns the device for the given chip address on a particular bus
523  * @chip_addr:	Chip address for the new device
525  * @devp:	Returns pointer to new device if found or -ENODEV if not
532  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
534  * This decodes the chip address from a device tree node and puts it into
542 int i2c_chip_ofdata_to_platdata(struct udevice *dev, struct dm_i2c_chip *chip);
545  * i2c_dump_msgs() - Dump a list of I2C messages
562  * use of stack-based variables are OK (the initial stack size is
594 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
595 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
598 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
642 	uint8_t		chip;  member
650 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
657 #define	I2C_BUS			gd->cur_i2c_bus
660 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
661 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
697  * Initialization, must be called once on start up, may be called
710  *  Returns index of currently active I2C bus.  Zero-based.
720  *	bus - bus index, zero based
722  *	Returns: 0 on success, not 0 on failure
732  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
737  * Probe the given I2C chip address.  Returns 0 if a chip responded,
738  * not 0 on failure.
740 int i2c_probe(uint8_t chip);
744  *   chip:    I2C chip address, range 0..127
745  *   addr:    Memory (register) address within the chip
752  *   Returns: 0 on success, not 0 on failure
754 int i2c_read(uint8_t chip, unsigned int addr, int alen,
757 int i2c_write(uint8_t chip, unsigned int addr, int alen,
772  *	speed - bus speed in Hz
790  * Probe the given I2C chip address.  Returns 0 if a chip responded,
791  * not 0 on failure.
793 int i2c_probe(uchar chip);
797  *   chip:    I2C chip address, range 0..127
798  *   addr:    Memory (register) address within the chip
805  *   Returns: 0 on success, not 0 on failure
807 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
808 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
846  *	bus - bus index, zero based
848  *	Returns: 0 on success, not 0 on failure
856  *  Returns index of currently active I2C bus.  Zero-based.
866  *	speed - bus speed in Hz
868  *	Returns: 0 on success, not 0 on failure
929  * @return the number of I2C bus (zero based), or -1 on error
938  * @return 0 if port was reset, -1 if not found