/* SPDX-License-Identifier: GPL-2.0+ */ /* * Copyright (C) 2009 Sergey Kubushyn * Copyright (C) 2009 - 2013 Heiko Schocher * Changes for multibus/multiadapter I2C support. * * (C) Copyright 2001 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. * * The original I2C interface was * (C) 2000 by Paolo Scaffardi (arsenio@tin.it) * AIRVENT SAM s.p.a - RIMINI(ITALY) * but has been changed substantially. */ #ifndef _I2C_H_ #define _I2C_H_ #include /* * For now there are essentially two parts to this file - driver model * here at the top, and the older code below (with CONFIG_SYS_I2C_LEGACY being * most recent). The plan is to migrate everything to driver model. * The driver model structures and API are separate as they are different * enough as to be incompatible for compilation purposes. */ enum dm_i2c_chip_flags { DM_I2C_CHIP_10BIT = 1 << 0, /* Use 10-bit addressing */ DM_I2C_CHIP_RD_ADDRESS = 1 << 1, /* Send address for each read byte */ DM_I2C_CHIP_WR_ADDRESS = 1 << 2, /* Send address for each write byte */ }; /** enum i2c_speed_mode - standard I2C speed modes */ enum i2c_speed_mode { IC_SPEED_MODE_STANDARD, IC_SPEED_MODE_FAST, IC_SPEED_MODE_FAST_PLUS, IC_SPEED_MODE_HIGH, IC_SPEED_MODE_FAST_ULTRA, IC_SPEED_MODE_COUNT, }; /** enum i2c_speed_rate - standard I2C speeds in Hz */ enum i2c_speed_rate { I2C_SPEED_STANDARD_RATE = 100000, I2C_SPEED_FAST_RATE = 400000, I2C_SPEED_FAST_PLUS_RATE = 1000000, I2C_SPEED_HIGH_RATE = 3400000, I2C_SPEED_FAST_ULTRA_RATE = 5000000, }; /** enum i2c_address_mode - available address modes */ enum i2c_address_mode { I2C_MODE_7_BIT, I2C_MODE_10_BIT }; /** enum i2c_device_t - Types of I2C devices, used for compatible strings */ enum i2c_device_t { I2C_DEVICE_GENERIC, I2C_DEVICE_HID_OVER_I2C, }; struct udevice; /** * struct dm_i2c_chip - information about an i2c chip * * An I2C chip is a device on the I2C bus. It sits at a particular address * and normally supports 7-bit or 10-bit addressing. * * To obtain this structure, use dev_get_parent_plat(dev) where dev is * the chip to examine. * * @chip_addr: Chip address on bus * @offset_len: Length of offset in bytes. A single byte offset can * represent up to 256 bytes. A value larger than 1 may be * needed for larger devices. * @flags: Flags for this chip (dm_i2c_chip_flags) * @chip_addr_offset_mask: Mask of offset bits within chip_addr. Used for * devices which steal addresses as part of offset. * If offset_len is zero, then the offset is encoded * completely within the chip address itself. * e.g. a devce with chip address of 0x2c with 512 * registers might use the bottom bit of the address * to indicate which half of the address space is being * accessed while still only using 1 byte offset. * This means it will respond to chip address 0x2c and * 0x2d. * A real world example is the Atmel AT24C04. It's * datasheet explains it's usage of this addressing * mode. * @emul: Emulator for this chip address (only used for emulation) * @emul_idx: Emulator index, used for of-platdata and set by each i2c chip's * bind() method. This allows i2c_emul_find() to work with of-platdata. */ struct dm_i2c_chip { uint chip_addr; uint offset_len; uint flags; uint chip_addr_offset_mask; #ifdef CONFIG_SANDBOX struct udevice *emul; bool test_mode; int emul_idx; #endif }; /** * struct dm_i2c_bus- information about an i2c bus * * An I2C bus contains 0 or more chips on it, each at its own address. The * bus can operate at different speeds (measured in Hz, typically 100KHz * or 400KHz). * * To obtain this structure, use dev_get_uclass_priv(bus) where bus is the * I2C bus udevice. * * @speed_hz: Bus speed in hertz (typically 100000) * @max_transaction_bytes: Maximal size of single I2C transfer */ struct dm_i2c_bus { int speed_hz; int max_transaction_bytes; }; /* * Not all of these flags are implemented in the U-Boot API */ enum dm_i2c_msg_flags { I2C_M_TEN = 0x0010, /* ten-bit chip address */ I2C_M_RD = 0x0001, /* read data, from slave to master */ I2C_M_STOP = 0x8000, /* send stop after this message */ I2C_M_NOSTART = 0x4000, /* no start before this message */ I2C_M_REV_DIR_ADDR = 0x2000, /* invert polarity of R/W bit */ I2C_M_IGNORE_NAK = 0x1000, /* continue after NAK */ I2C_M_NO_RD_ACK = 0x0800, /* skip the Ack bit on reads */ I2C_M_RECV_LEN = 0x0400, /* length is first received byte */ }; /** * struct i2c_msg - an I2C message * * @addr: Slave address * @flags: Flags (see enum dm_i2c_msg_flags) * @len: Length of buffer in bytes, may be 0 for a probe * @buf: Buffer to send/receive, or NULL if no data */ struct i2c_msg { uint addr; uint flags; uint len; u8 *buf; }; /** * struct i2c_msg_list - a list of I2C messages * * This is called i2c_rdwr_ioctl_data in Linux but the name does not seem * appropriate in U-Boot. * * @msg: Pointer to i2c_msg array * @nmsgs: Number of elements in the array */ struct i2c_msg_list { struct i2c_msg *msgs; uint nmsgs; }; /** * dm_i2c_read() - read bytes from an I2C chip * * To obtain an I2C device (called a 'chip') given the I2C bus address you * can use i2c_get_chip(). To obtain a bus by bus number use * uclass_get_device_by_seq(UCLASS_I2C, ). * * To set the address length of a devce use i2c_set_addr_len(). It * defaults to 1. * * @dev: Chip to read from * @offset: Offset within chip to start reading * @buffer: Place to put data * @len: Number of bytes to read * * Return: 0 on success, -ve on failure */ int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len); /** * dm_i2c_write() - write bytes to an I2C chip * * See notes for dm_i2c_read() above. * * @dev: Chip to write to * @offset: Offset within chip to start writing * @buffer: Buffer containing data to write * @len: Number of bytes to write * * Return: 0 on success, -ve on failure */ int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer, int len); /** * dm_i2c_probe() - probe a particular chip address * * This can be useful to check for the existence of a chip on the bus. * It is typically implemented by writing the chip address to the bus * and checking that the chip replies with an ACK. * * @bus: Bus to probe * @chip_addr: 7-bit address to probe (10-bit and others are not supported) * @chip_flags: Flags for the probe (see enum dm_i2c_chip_flags) * @devp: Returns the device found, or NULL if none * Return: 0 if a chip was found at that address, -ve if not */ int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags, struct udevice **devp); /** * dm_i2c_reg_read() - Read a value from an I2C register * * This reads a single value from the given address in an I2C chip * * @dev: Device to use for transfer * @addr: Address to read from * Return: value read, or -ve on error */ int dm_i2c_reg_read(struct udevice *dev, uint offset); /** * dm_i2c_reg_write() - Write a value to an I2C register * * This writes a single value to the given address in an I2C chip * * @dev: Device to use for transfer * @addr: Address to write to * @val: Value to write (normally a byte) * Return: 0 on success, -ve on error */ int dm_i2c_reg_write(struct udevice *dev, uint offset, unsigned int val); /** * dm_i2c_reg_clrset() - Apply bitmask to an I2C register * * Read value, apply bitmask and write modified value back to the * given address in an I2C chip * * @dev: Device to use for transfer * @offset: Address for the R/W operation * @clr: Bitmask of bits that should be cleared * @set: Bitmask of bits that should be set * Return: 0 on success, -ve on error */ int dm_i2c_reg_clrset(struct udevice *dev, uint offset, u32 clr, u32 set); /** * dm_i2c_xfer() - Transfer messages over I2C * * This transfers a raw message. It is best to use dm_i2c_reg_read/write() * instead. * * @dev: Device to use for transfer * @msg: List of messages to transfer * @nmsgs: Number of messages to transfer * Return: 0 on success, -ve on error */ int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs); /** * dm_i2c_set_bus_speed() - set the speed of a bus * * @bus: Bus to adjust * @speed: Requested speed in Hz * Return: 0 if OK, -EINVAL for invalid values */ int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed); /** * dm_i2c_get_bus_speed() - get the speed of a bus * * @bus: Bus to check * Return: speed of selected I2C bus in Hz, -ve on error */ int dm_i2c_get_bus_speed(struct udevice *bus); /** * i2c_set_chip_flags() - set flags for a chip * * Typically addresses are 7 bits, but for 10-bit addresses you should set * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing. * * @dev: Chip to adjust * @flags: New flags * Return: 0 if OK, -EINVAL if value is unsupported, other -ve value on error */ int i2c_set_chip_flags(struct udevice *dev, uint flags); /** * i2c_get_chip_flags() - get flags for a chip * * @dev: Chip to check * @flagsp: Place to put flags * Return: 0 if OK, other -ve value on error */ int i2c_get_chip_flags(struct udevice *dev, uint *flagsp); /** * i2c_set_offset_len() - set the offset length for a chip * * The offset used to access a chip may be up to 4 bytes long. Typically it * is only 1 byte, which is enough for chips with 256 bytes of memory or * registers. The default value is 1, but you can call this function to * change it. * * @offset_len: New offset length value (typically 1 or 2) */ int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len); /** * i2c_get_offset_len() - get the offset length for a chip * * @return: Current offset length value (typically 1 or 2) */ int i2c_get_chip_offset_len(struct udevice *dev); /** * i2c_set_chip_addr_offset_mask() - set mask of address bits usable by offset * * Some devices listen on multiple chip addresses to achieve larger offsets * than their single or multiple byte offsets would allow for. You can use this * function to set the bits that are valid to be used for offset overflow. * * @mask: The mask to be used for high offset bits within address * Return: 0 if OK, other -ve value on error */ int i2c_set_chip_addr_offset_mask(struct udevice *dev, uint mask); /* * i2c_get_chip_addr_offset_mask() - get mask of address bits usable by offset * * Return: current chip addr offset mask */ uint i2c_get_chip_addr_offset_mask(struct udevice *dev); /** * i2c_deblock() - recover a bus that is in an unknown state * * See the deblock() method in 'struct dm_i2c_ops' for full information * * @bus: Bus to recover * Return: 0 if OK, -ve on error */ int i2c_deblock(struct udevice *bus); /** * i2c_deblock_gpio_loop() - recover a bus from an unknown state by toggling SDA/SCL * * This is the inner logic used for toggling I2C SDA/SCL lines as GPIOs * for deblocking the I2C bus. * * @sda_pin: SDA GPIO * @scl_pin: SCL GPIO * @scl_count: Number of SCL clock cycles generated to deblock SDA * @start_count:Number of I2C start conditions sent after deblocking SDA * @delay: Delay between SCL clock line changes * Return: 0 if OK, -ve on error */ struct gpio_desc; int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin, struct gpio_desc *scl_pin, unsigned int scl_count, unsigned int start_count, unsigned int delay); /** * struct dm_i2c_ops - driver operations for I2C uclass * * Drivers should support these operations unless otherwise noted. These * operations are intended to be used by uclass code, not directly from * other code. */ struct dm_i2c_ops { /** * xfer() - transfer a list of I2C messages * * @bus: Bus to read from * @msg: List of messages to transfer * @nmsgs: Number of messages in the list * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte, * -ECOMM if the speed cannot be supported, -EPROTO if the chip * flags cannot be supported, other -ve value on some other error */ int (*xfer)(struct udevice *bus, struct i2c_msg *msg, int nmsgs); /** * probe_chip() - probe for the presense of a chip address * * This function is optional. If omitted, the uclass will send a zero * length message instead. * * @bus: Bus to probe * @chip_addr: Chip address to probe * @chip_flags: Probe flags (enum dm_i2c_chip_flags) * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back * to default probem other -ve value on error */ int (*probe_chip)(struct udevice *bus, uint chip_addr, uint chip_flags); /** * set_bus_speed() - set the speed of a bus (optional) * * The bus speed value will be updated by the uclass if this function * does not return an error. This method is optional - if it is not * provided then the driver can read the speed from * dev_get_uclass_priv(bus)->speed_hz * * @bus: Bus to adjust * @speed: Requested speed in Hz * @return 0 if OK, -EINVAL for invalid values */ int (*set_bus_speed)(struct udevice *bus, unsigned int speed); /** * get_bus_speed() - get the speed of a bus (optional) * * Normally this can be provided by the uclass, but if you want your * driver to check the bus speed by looking at the hardware, you can * implement that here. This method is optional. This method would * normally be expected to return dev_get_uclass_priv(bus)->speed_hz. * * @bus: Bus to check * @return speed of selected I2C bus in Hz, -ve on error */ int (*get_bus_speed)(struct udevice *bus); /** * set_flags() - set the flags for a chip (optional) * * This is generally implemented by the uclass, but drivers can * check the value to ensure that unsupported options are not used. * This method is optional. If provided, this method will always be * called when the flags change. * * @dev: Chip to adjust * @flags: New flags value * @return 0 if OK, -EINVAL if value is unsupported */ int (*set_flags)(struct udevice *dev, uint flags); /** * deblock() - recover a bus that is in an unknown state * * I2C is a synchronous protocol and resets of the processor in the * middle of an access can block the I2C Bus until a powerdown of * the full unit is done. This is because slaves can be stuck * waiting for addition bus transitions for a transaction that will * never complete. Resetting the I2C master does not help. The only * way is to force the bus through a series of transitions to make * sure that all slaves are done with the transaction. This method * performs this 'deblocking' if support by the driver. * * This method is optional. */ int (*deblock)(struct udevice *bus); }; #define i2c_get_ops(dev) ((struct dm_i2c_ops *)(dev)->driver->ops) /** * struct i2c_mux_ops - operations for an I2C mux * * The current mux state is expected to be stored in the mux itself since * it is the only thing that knows how to make things work. The mux can * record the current state and then avoid switching unless it is necessary. * So select() can be skipped if the mux is already in the correct state. * Also deselect() can be made a nop if required. */ struct i2c_mux_ops { /** * select() - select one of of I2C buses attached to a mux * * This will be called when there is no bus currently selected by the * mux. This method does not need to deselect the old bus since * deselect() will be already have been called if necessary. * * @mux: Mux device * @bus: I2C bus to select * @channel: Channel number correponding to the bus to select * @return 0 if OK, -ve on error */ int (*select)(struct udevice *mux, struct udevice *bus, uint channel); /** * deselect() - select one of of I2C buses attached to a mux * * This is used to deselect the currently selected I2C bus. * * @mux: Mux device * @bus: I2C bus to deselect * @channel: Channel number correponding to the bus to deselect * @return 0 if OK, -ve on error */ int (*deselect)(struct udevice *mux, struct udevice *bus, uint channel); }; #define i2c_mux_get_ops(dev) ((struct i2c_mux_ops *)(dev)->driver->ops) /** * i2c_get_chip() - get a device to use to access a chip on a bus * * This returns the device for the given chip address. The device can then * be used with calls to i2c_read(), i2c_write(), i2c_probe(), etc. * * @bus: Bus to examine * @chip_addr: Chip address for the new device * @offset_len: Length of a register offset in bytes (normally 1) * @devp: Returns pointer to new device if found or -ENODEV if not * found */ int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len, struct udevice **devp); /** * i2c_get_chip_for_busnum() - get a device to use to access a chip on * a bus number * * This returns the device for the given chip address on a particular bus * number. * * @busnum: Bus number to examine * @chip_addr: Chip address for the new device * @offset_len: Length of a register offset in bytes (normally 1) * @devp: Returns pointer to new device if found or -ENODEV if not * found */ int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len, struct udevice **devp); /** * i2c_chip_of_to_plat() - Decode standard I2C platform data * * This decodes the chip address from a device tree node and puts it into * its dm_i2c_chip structure. This should be called in your driver's * of_to_plat() method. * * @blob: Device tree blob * @node: Node offset to read from * @spi: Place to put the decoded information */ int i2c_chip_of_to_plat(struct udevice *dev, struct dm_i2c_chip *chip); /** * i2c_dump_msgs() - Dump a list of I2C messages * * This may be useful for debugging. * * @msg: Message list to dump * @nmsgs: Number of messages */ void i2c_dump_msgs(struct i2c_msg *msg, int nmsgs); /** * i2c_emul_find() - Find an emulator for an i2c sandbox device * * This looks at the device's 'emul' phandle * * @dev: Device to find an emulator for * @emulp: Returns the associated emulator, if found * * Return: 0 if OK, -ENOENT or -ENODEV if not found */ int i2c_emul_find(struct udevice *dev, struct udevice **emulp); /** * i2c_emul_set_idx() - Set the emulator index for an i2c sandbox device * * With of-platdata we cannot find the emulator using the device tree, so rely * on the bind() method of each i2c driver calling this function to tell us * the of-platdata idx of the emulator * * @dev: i2c device to set the emulator for * @emul_idx: of-platdata index for that emulator */ void i2c_emul_set_idx(struct udevice *dev, int emul_idx); /** * i2c_emul_get_device() - Find the device being emulated * * Given an emulator this returns the associated device * * @emul: Emulator for the device * Return: device that @emul is emulating */ struct udevice *i2c_emul_get_device(struct udevice *emul); /* ACPI operations for generic I2C devices */ extern struct acpi_ops i2c_acpi_ops; /** * acpi_i2c_of_to_plat() - Read properties intended for ACPI * * This reads the generic I2C properties from the device tree, so that these * can be used to create ACPI information for the device. * * See the i2c/generic-acpi.txt binding file for information about the * properties. * * @dev: I2C device to process * Return: 0 if OK, -EINVAL if acpi,hid is not present */ int acpi_i2c_of_to_plat(struct udevice *dev); #ifdef CONFIG_SYS_I2C_EARLY_INIT void i2c_early_init_f(void); #endif #if !CONFIG_IS_ENABLED(DM_I2C) /* * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING * * The implementation MUST NOT use static or global variables if the * I2C routines are used to read SDRAM configuration information * because this is done before the memories are initialized. Limited * use of stack-based variables are OK (the initial stack size is * limited). * * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING */ /* * Configuration items. */ #define I2C_RXTX_LEN 128 /* maximum tx/rx buffer length */ #if !defined(CFG_SYS_I2C_MAX_HOPS) /* no muxes used bus = i2c adapters */ #define CONFIG_SYS_I2C_DIRECT_BUS 1 #define CFG_SYS_I2C_MAX_HOPS 0 #define CFG_SYS_NUM_I2C_BUSES ll_entry_count(struct i2c_adapter, i2c) #else /* we use i2c muxes */ #undef CONFIG_SYS_I2C_DIRECT_BUS #endif /* define the I2C bus number for RTC and DTT if not already done */ #if !defined(CFG_SYS_RTC_BUS_NUM) #define CFG_SYS_RTC_BUS_NUM 0 #endif struct i2c_adapter { void (*init)(struct i2c_adapter *adap, int speed, int slaveaddr); int (*probe)(struct i2c_adapter *adap, uint8_t chip); int (*read)(struct i2c_adapter *adap, uint8_t chip, uint addr, int alen, uint8_t *buffer, int len); int (*write)(struct i2c_adapter *adap, uint8_t chip, uint addr, int alen, uint8_t *buffer, int len); uint (*set_bus_speed)(struct i2c_adapter *adap, uint speed); int speed; int waitdelay; int slaveaddr; int init_done; int hwadapnr; char *name; }; #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \ _set_speed, _speed, _slaveaddr, _hwadapnr, _name) \ { \ .init = _init, \ .probe = _probe, \ .read = _read, \ .write = _write, \ .set_bus_speed = _set_speed, \ .speed = _speed, \ .slaveaddr = _slaveaddr, \ .init_done = 0, \ .hwadapnr = _hwadapnr, \ .name = #_name \ }; #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \ _set_speed, _speed, _slaveaddr, _hwadapnr) \ ll_entry_declare(struct i2c_adapter, _name, i2c) = \ U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \ _set_speed, _speed, _slaveaddr, _hwadapnr, _name); struct i2c_adapter *i2c_get_adapter(int index); #ifndef CONFIG_SYS_I2C_DIRECT_BUS struct i2c_mux { int id; char name[16]; }; struct i2c_next_hop { struct i2c_mux mux; uint8_t chip; uint8_t channel; }; struct i2c_bus_hose { int adapter; struct i2c_next_hop next_hop[CFG_SYS_I2C_MAX_HOPS]; }; #define I2C_NULL_HOP {{-1, ""}, 0, 0} extern struct i2c_bus_hose i2c_bus[]; #define I2C_ADAPTER(bus) i2c_bus[bus].adapter #else #define I2C_ADAPTER(bus) bus #endif #define I2C_BUS gd->cur_i2c_bus #define I2C_ADAP_NR(bus) i2c_get_adapter(I2C_ADAPTER(bus)) #define I2C_ADAP I2C_ADAP_NR(gd->cur_i2c_bus) #define I2C_ADAP_HWNR (I2C_ADAP->hwadapnr) #ifndef CONFIG_SYS_I2C_DIRECT_BUS #define I2C_MUX_PCA9540_ID 1 #define I2C_MUX_PCA9540 {I2C_MUX_PCA9540_ID, "PCA9540B"} #define I2C_MUX_PCA9542_ID 2 #define I2C_MUX_PCA9542 {I2C_MUX_PCA9542_ID, "PCA9542A"} #define I2C_MUX_PCA9544_ID 3 #define I2C_MUX_PCA9544 {I2C_MUX_PCA9544_ID, "PCA9544A"} #define I2C_MUX_PCA9547_ID 4 #define I2C_MUX_PCA9547 {I2C_MUX_PCA9547_ID, "PCA9547A"} #define I2C_MUX_PCA9548_ID 5 #define I2C_MUX_PCA9548 {I2C_MUX_PCA9548_ID, "PCA9548"} #endif #ifndef I2C_SOFT_DECLARATIONS # if (defined(CONFIG_AT91RM9200) || \ defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9261) || \ defined(CONFIG_AT91SAM9263)) # define I2C_SOFT_DECLARATIONS at91_pio_t *pio = (at91_pio_t *) ATMEL_BASE_PIOA; # else # define I2C_SOFT_DECLARATIONS # endif #endif /* * Initialization, must be called once on start up, may be called * repeatedly to change the speed and slave addresses. */ void i2c_init(int speed, int slaveaddr); void i2c_init_board(void); #if CONFIG_IS_ENABLED(SYS_I2C_LEGACY) /* * i2c_get_bus_num: * * Returns index of currently active I2C bus. Zero-based. */ unsigned int i2c_get_bus_num(void); /* * i2c_set_bus_num: * * Change the active I2C bus. Subsequent read/write calls will * go to this one. * * bus - bus index, zero based * * Returns: 0 on success, not 0 on failure * */ int i2c_set_bus_num(unsigned int bus); /* * i2c_init_all(): * * Initializes all I2C adapters in the system. All i2c_adap structures must * be initialized beforehead with function pointers and data, including * speed and slaveaddr. Returns 0 on success, non-0 on failure. */ void i2c_init_all(void); /* * Probe the given I2C chip address. Returns 0 if a chip responded, * not 0 on failure. */ int i2c_probe(uint8_t chip); /* * Read/Write interface: * chip: I2C chip address, range 0..127 * addr: Memory (register) address within the chip * alen: Number of bytes to use for addr (typically 1, 2 for larger * memories, 0 for register type devices with only one * register) * buffer: Where to read/write the data * len: How many bytes to read/write * * Returns: 0 on success, not 0 on failure */ int i2c_read(uint8_t chip, unsigned int addr, int alen, uint8_t *buffer, int len); int i2c_write(uint8_t chip, unsigned int addr, int alen, uint8_t *buffer, int len); /* * Utility routines to read/write registers. */ uint8_t i2c_reg_read(uint8_t addr, uint8_t reg); void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val); /* * i2c_set_bus_speed: * * Change the speed of the active I2C bus * * speed - bus speed in Hz * * Returns: new bus speed * */ unsigned int i2c_set_bus_speed(unsigned int speed); /* * i2c_get_bus_speed: * * Returns speed of currently active I2C bus in Hz */ unsigned int i2c_get_bus_speed(void); #else /* * Probe the given I2C chip address. Returns 0 if a chip responded, * not 0 on failure. */ int i2c_probe(uchar chip); /* * Read/Write interface: * chip: I2C chip address, range 0..127 * addr: Memory (register) address within the chip * alen: Number of bytes to use for addr (typically 1, 2 for larger * memories, 0 for register type devices with only one * register) * buffer: Where to read/write the data * len: How many bytes to read/write * * Returns: 0 on success, not 0 on failure */ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len); int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len); /* * Utility routines to read/write registers. */ static inline u8 i2c_reg_read(u8 addr, u8 reg) { u8 buf; #ifdef DEBUG printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg); #endif i2c_read(addr, reg, 1, &buf, 1); return buf; } static inline void i2c_reg_write(u8 addr, u8 reg, u8 val) { #ifdef DEBUG printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n", __func__, addr, reg, val); #endif i2c_write(addr, reg, 1, &val, 1); } /* * Functions for setting the current I2C bus and its speed */ /* * i2c_set_bus_num: * * Change the active I2C bus. Subsequent read/write calls will * go to this one. * * bus - bus index, zero based * * Returns: 0 on success, not 0 on failure * */ int i2c_set_bus_num(unsigned int bus); /* * i2c_get_bus_num: * * Returns index of currently active I2C bus. Zero-based. */ unsigned int i2c_get_bus_num(void); /* * i2c_set_bus_speed: * * Change the speed of the active I2C bus * * speed - bus speed in Hz * * Returns: 0 on success, not 0 on failure * */ int i2c_set_bus_speed(unsigned int); /* * i2c_get_bus_speed: * * Returns speed of currently active I2C bus in Hz */ unsigned int i2c_get_bus_speed(void); #endif /* CONFIG_SYS_I2C_LEGACY */ /* * only for backwardcompatibility, should go away if we switched * completely to new multibus support. */ #if CONFIG_IS_ENABLED(SYS_I2C_LEGACY) || defined(CFG_I2C_MULTI_BUS) # if !defined(CFG_SYS_MAX_I2C_BUS) # define CFG_SYS_MAX_I2C_BUS 2 # endif # define I2C_MULTI_BUS 1 #else # define CFG_SYS_MAX_I2C_BUS 1 # define I2C_MULTI_BUS 0 #endif /* NOTE: These two functions MUST be always_inline to avoid code growth! */ static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline)); static inline unsigned int I2C_GET_BUS(void) { return I2C_MULTI_BUS ? i2c_get_bus_num() : 0; } static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline)); static inline void I2C_SET_BUS(unsigned int bus) { if (I2C_MULTI_BUS) i2c_set_bus_num(bus); } /* Multi I2C definitions */ enum { I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7, I2C_8, I2C_9, I2C_10, }; /** * Get FDT values for i2c bus. * * @param blob Device tree blbo * Return: the number of I2C bus */ void board_i2c_init(const void *blob); /** * Find the I2C bus number by given a FDT I2C node. * * @param blob Device tree blbo * @param node FDT I2C node to find * Return: the number of I2C bus (zero based), or -1 on error */ int i2c_get_bus_num_fdt(int node); /** * Reset the I2C bus represented by the given a FDT I2C node. * * @param blob Device tree blbo * @param node FDT I2C node to find * Return: 0 if port was reset, -1 if not found */ int i2c_reset_port_fdt(const void *blob, int node); #endif /* !CONFIG_DM_I2C */ #endif /* _I2C_H_ */