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
39  * and normally supports 7-bit or 10-bit addressing.
62  * struct dm_i2c_bus- information about an i2c bus
71  * @speed_hz: Bus speed in hertz (typically 100000)
78  * Not all of these flags are implemented in the U-Boot API
81 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
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
135  * @return 0 on success, -ve on failure
140  * dm_i2c_write() - write bytes to an I2C chip
149  * @return 0 on success, -ve on failure
155  * dm_i2c_probe() - probe a particular chip address
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
177  * @return value read, or -ve on error
182  * dm_i2c_reg_write() - Write a value to an I2C register
189  * @return 0 on success, -ve on error
194  * dm_i2c_reg_clrset() - Apply bitmask to an I2C register
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
224  * @speed:	Requested speed in Hz
225  * @return 0 if OK, -EINVAL for invalid values
227 int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed);
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.
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
254  * @return 0 if OK, other -ve value on error
259  * i2c_set_offset_len() - set the offset length for a chip
271  * i2c_get_offset_len() - get the offset length for a chip
273  * @return:	Current offset length value (typically 1 or 2)
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
299  * set to @addr. @alen must match the current setting for the device.
305  * i2c_write() - Compatibility function for driver model
308  * set to @addr. @alen must match the current setting for the device.
314  * i2c_get_bus_num_fdt() - Compatibility function for driver model
321  * i2c_get_bus_num() - Compatibility function for driver model
323  * @return the 'current' bus number
328  * i2c_set_bus_num() - Compatibility function for driver model
330  * Sets the 'current' bus
345  * i2c_init() - Compatibility function for driver model
349 void i2c_init(int speed, int slaveaddr);
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
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)
404 	 * The bus speed value will be updated by the uclass if this function
405 	 * does not return an error. This method is optional - if it is not
406 	 * provided then the driver can read the speed from
407 	 * dev_get_uclass_priv(bus)->speed_hz
410 	 * @speed:	Requested speed in Hz
411 	 * @return 0 if OK, -EINVAL for invalid values
413 	int (*set_bus_speed)(struct udevice *bus, unsigned int speed);
416 	 * get_bus_speed() - get the speed of a bus (optional)
419 	 * driver to check the bus speed by looking at the hardware, you can
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)
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
464  * The current mux state is expected to be stored in the mux itself since
466  * record the current state and then avoid switching unless it is necessary.
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
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
525  * @devp:	Returns pointer to new device if found or -ENODEV if not
532  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
545  * i2c_dump_msgs() - Dump a list of I2C messages
562  * use of stack-based variables are OK (the initial stack size is
592 	void		(*init)(struct i2c_adapter *adap, int speed,
602 				uint speed);
603 	int		speed;  member
619 		.speed		=	_speed, \
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)
698  * repeatedly to change the speed and slave addresses.
703 void i2c_init(int speed, int slaveaddr);
710  *  Returns index of currently active I2C bus.  Zero-based.
720  *	bus - bus index, zero based
732  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
770  *  Change the speed of the active I2C bus
772  *	speed - bus speed in Hz
774  *	Returns: new bus speed
777 unsigned int i2c_set_bus_speed(unsigned int speed);
782  *  Returns speed of currently active I2C bus in Hz
837  * Functions for setting the current I2C bus and its speed
846  *	bus - bus index, zero based
856  *  Returns index of currently active I2C bus.  Zero-based.
864  *  Change the speed of the active I2C bus
866  *	speed - bus speed in Hz
876  *  Returns speed of currently active I2C bus in Hz
929  * @return the number of I2C bus (zero based), or -1 on error
938  * @return 0 if port was reset, -1 if not found