/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * i2c.h - definitions for the Linux i2c bus interface * Copyright (C) 1995-2000 Simon G. Vogl * Copyright (C) 2013-2019 Wolfram Sang <wsa@kernel.org> * * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and * Frodo Looijaard <frodol@dds.nl> */ #ifndef _LINUX_I2C_H #define _LINUX_I2C_H #include <linux/acpi.h> /* for acpi_handle */ #include <linux/bits.h> #include <linux/mod_devicetable.h> #include <linux/device.h> /* for struct device */ #include <linux/sched.h> /* for completion */ #include <linux/mutex.h> #include <linux/regulator/consumer.h> #include <linux/rtmutex.h> #include <linux/irqdomain.h> /* for Host Notify IRQ */ #include <linux/of.h> /* for struct device_node */ #include <linux/swab.h> /* for swab16 */ #include <uapi/linux/i2c.h> extern struct bus_type i2c_bus_type; extern struct device_type i2c_adapter_type; extern struct device_type i2c_client_type; /* --- General options ------------------------------------------------ */ struct i2c_msg; struct i2c_algorithm; struct i2c_adapter; struct i2c_client; struct i2c_driver; struct i2c_device_identity; union i2c_smbus_data; struct i2c_board_info; enum i2c_slave_event; typedef int (*i2c_slave_cb_t)(struct i2c_client *client, enum i2c_slave_event event, u8 *val); /* I2C Frequency Modes */ #define I2C_MAX_STANDARD_MODE_FREQ 100000 #define I2C_MAX_FAST_MODE_FREQ 400000 #define I2C_MAX_FAST_MODE_PLUS_FREQ 1000000 #define I2C_MAX_TURBO_MODE_FREQ 1400000 #define I2C_MAX_HIGH_SPEED_MODE_FREQ 3400000 #define I2C_MAX_ULTRA_FAST_MODE_FREQ 5000000 struct module; struct property_entry; #if IS_ENABLED(CONFIG_I2C) /* Return the Frequency mode string based on the bus frequency */ const char *i2c_freq_mode_string(u32 bus_freq_hz); /* * The master routines are the ones normally used to transmit data to devices * on a bus (or read from them). Apart from two basic transfer functions to * transmit one message at a time, a more complex version can be used to * transmit an arbitrary number of messages without interruption. * @count must be less than 64k since msg.len is u16. */ int i2c_transfer_buffer_flags(const struct i2c_client *client, char *buf, int count, u16 flags); /** * i2c_master_recv - issue a single I2C message in master receive mode * @client: Handle to slave device * @buf: Where to store data read from slave * @count: How many bytes to read, must be less than 64k since msg.len is u16 * * Returns negative errno, or else the number of bytes read. */ static inline int i2c_master_recv(const struct i2c_client *client, char *buf, int count) { return i2c_transfer_buffer_flags(client, buf, count, I2C_M_RD); }; /** * i2c_master_recv_dmasafe - issue a single I2C message in master receive mode * using a DMA safe buffer * @client: Handle to slave device * @buf: Where to store data read from slave, must be safe to use with DMA * @count: How many bytes to read, must be less than 64k since msg.len is u16 * * Returns negative errno, or else the number of bytes read. */ static inline int i2c_master_recv_dmasafe(const struct i2c_client *client, char *buf, int count) { return i2c_transfer_buffer_flags(client, buf, count, I2C_M_RD | I2C_M_DMA_SAFE); }; /** * i2c_master_send - issue a single I2C message in master transmit mode * @client: Handle to slave device * @buf: Data that will be written to the slave * @count: How many bytes to write, must be less than 64k since msg.len is u16 * * Returns negative errno, or else the number of bytes written. */ static inline int i2c_master_send(const struct i2c_client *client, const char *buf, int count) { return i2c_transfer_buffer_flags(client, (char *)buf, count, 0); }; /** * i2c_master_send_dmasafe - issue a single I2C message in master transmit mode * using a DMA safe buffer * @client: Handle to slave device * @buf: Data that will be written to the slave, must be safe to use with DMA * @count: How many bytes to write, must be less than 64k since msg.len is u16 * * Returns negative errno, or else the number of bytes written. */ static inline int i2c_master_send_dmasafe(const struct i2c_client *client, const char *buf, int count) { return i2c_transfer_buffer_flags(client, (char *)buf, count, I2C_M_DMA_SAFE); }; /* Transfer num messages. */ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); /* Unlocked flavor */ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); /* This is the very generalized SMBus access routine. You probably do not want to use this, though; one of the functions below may be much easier, and probably just as fast. Note that we use i2c_adapter here, because you do not need a specific smbus adapter to call this function. */ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, char read_write, u8 command, int protocol, union i2c_smbus_data *data); /* Unlocked flavor */ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, char read_write, u8 command, int protocol, union i2c_smbus_data *data); /* Now follow the 'nice' access routines. These also document the calling conventions of i2c_smbus_xfer. */ u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count); s32 i2c_smbus_read_byte(const struct i2c_client *client); s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value); s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command); s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, u8 value); s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command); s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, u16 value); static inline s32 i2c_smbus_read_word_swapped(const struct i2c_client *client, u8 command) { s32 value = i2c_smbus_read_word_data(client, command); return (value < 0) ? value : swab16(value); } static inline s32 i2c_smbus_write_word_swapped(const struct i2c_client *client, u8 command, u16 value) { return i2c_smbus_write_word_data(client, command, swab16(value)); } /* Returns the number of read bytes */ s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, u8 *values); s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values); /* Returns the number of read bytes */ s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, u8 *values); s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values); s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, u8 command, u8 length, u8 *values); int i2c_get_device_id(const struct i2c_client *client, struct i2c_device_identity *id); const struct i2c_device_id *i2c_client_get_device_id(const struct i2c_client *client); #endif /* I2C */ /** * struct i2c_device_identity - i2c client device identification * @manufacturer_id: 0 - 4095, database maintained by NXP * @part_id: 0 - 511, according to manufacturer * @die_revision: 0 - 7, according to manufacturer */ struct i2c_device_identity { u16 manufacturer_id; #define I2C_DEVICE_ID_NXP_SEMICONDUCTORS 0 #define I2C_DEVICE_ID_NXP_SEMICONDUCTORS_1 1 #define I2C_DEVICE_ID_NXP_SEMICONDUCTORS_2 2 #define I2C_DEVICE_ID_NXP_SEMICONDUCTORS_3 3 #define I2C_DEVICE_ID_RAMTRON_INTERNATIONAL 4 #define I2C_DEVICE_ID_ANALOG_DEVICES 5 #define I2C_DEVICE_ID_STMICROELECTRONICS 6 #define I2C_DEVICE_ID_ON_SEMICONDUCTOR 7 #define I2C_DEVICE_ID_SPRINTEK_CORPORATION 8 #define I2C_DEVICE_ID_ESPROS_PHOTONICS_AG 9 #define I2C_DEVICE_ID_FUJITSU_SEMICONDUCTOR 10 #define I2C_DEVICE_ID_FLIR 11 #define I2C_DEVICE_ID_O2MICRO 12 #define I2C_DEVICE_ID_ATMEL 13 #define I2C_DEVICE_ID_NONE 0xffff u16 part_id; u8 die_revision; }; enum i2c_alert_protocol { I2C_PROTOCOL_SMBUS_ALERT, I2C_PROTOCOL_SMBUS_HOST_NOTIFY, }; /** * enum i2c_driver_flags - Flags for an I2C device driver * * @I2C_DRV_ACPI_WAIVE_D0_PROBE: Don't put the device in D0 state for probe */ enum i2c_driver_flags { I2C_DRV_ACPI_WAIVE_D0_PROBE = BIT(0), }; /** * struct i2c_driver - represent an I2C device driver * @class: What kind of i2c device we instantiate (for detect) * @probe: Callback for device binding * @remove: Callback for device unbinding * @shutdown: Callback for device shutdown * @alert: Alert callback, for example for the SMBus alert protocol * @command: Callback for bus-wide signaling (optional) * @driver: Device driver model driver * @id_table: List of I2C devices supported by this driver * @detect: Callback for device detection * @address_list: The I2C addresses to probe (for detect) * @clients: List of detected clients we created (for i2c-core use only) * @flags: A bitmask of flags defined in &enum i2c_driver_flags * * The driver.owner field should be set to the module owner of this driver. * The driver.name field should be set to the name of this driver. * * For automatic device detection, both @detect and @address_list must * be defined. @class should also be set, otherwise only devices forced * with module parameters will be created. The detect function must * fill at least the name field of the i2c_board_info structure it is * handed upon successful detection, and possibly also the flags field. * * If @detect is missing, the driver will still work fine for enumerated * devices. Detected devices simply won't be supported. This is expected * for the many I2C/SMBus devices which can't be detected reliably, and * the ones which can always be enumerated in practice. * * The i2c_client structure which is handed to the @detect callback is * not a real i2c_client. It is initialized just enough so that you can * call i2c_smbus_read_byte_data and friends on it. Don't do anything * else with it. In particular, calling dev_dbg and friends on it is * not allowed. */ struct i2c_driver { unsigned int class; /* Standard driver model interfaces */ int (*probe)(struct i2c_client *client); void (*remove)(struct i2c_client *client); /* driver model interfaces that don't relate to enumeration */ void (*shutdown)(struct i2c_client *client); /* Alert callback, for example for the SMBus alert protocol. * The format and meaning of the data value depends on the protocol. * For the SMBus alert protocol, there is a single bit of data passed * as the alert response's low bit ("event flag"). * For the SMBus Host Notify protocol, the data corresponds to the * 16-bit payload data reported by the slave device acting as master. */ void (*alert)(struct i2c_client *client, enum i2c_alert_protocol protocol, unsigned int data); /* a ioctl like command that can be used to perform specific functions * with the device. */ int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); struct device_driver driver; const struct i2c_device_id *id_table; /* Device detection callback for automatic device creation */ int (*detect)(struct i2c_client *client, struct i2c_board_info *info); const unsigned short *address_list; struct list_head clients; u32 flags; }; #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) /** * struct i2c_client - represent an I2C slave device * @flags: see I2C_CLIENT_* for possible flags * @addr: Address used on the I2C bus connected to the parent adapter. * @name: Indicates the type of the device, usually a chip name that's * generic enough to hide second-sourcing and compatible revisions. * @adapter: manages the bus segment hosting this I2C device * @dev: Driver model device node for the slave. * @init_irq: IRQ that was set at initialization * @irq: indicates the IRQ generated by this device (if any) * @detected: member of an i2c_driver.clients list or i2c-core's * userspace_devices list * @slave_cb: Callback when I2C slave mode of an adapter is used. The adapter * calls it to pass on slave events to the slave driver. * @devres_group_id: id of the devres group that will be created for resources * acquired when probing this device. * * An i2c_client identifies a single device (i.e. chip) connected to an * i2c bus. The behaviour exposed to Linux is defined by the driver * managing the device. */ struct i2c_client { unsigned short flags; /* div., see below */ #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ /* Must equal I2C_M_TEN below */ #define I2C_CLIENT_SLAVE 0x20 /* we are the slave */ #define I2C_CLIENT_HOST_NOTIFY 0x40 /* We want to use I2C host notify */ #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ #define I2C_CLIENT_SCCB 0x9000 /* Use Omnivision SCCB protocol */ /* Must match I2C_M_STOP|IGNORE_NAK */ unsigned short addr; /* chip address - NOTE: 7bit */ /* addresses are stored in the */ /* _LOWER_ 7 bits */ char name[I2C_NAME_SIZE]; struct i2c_adapter *adapter; /* the adapter we sit on */ struct device dev; /* the device structure */ int init_irq; /* irq set at initialization */ int irq; /* irq issued by device */ struct list_head detected; #if IS_ENABLED(CONFIG_I2C_SLAVE) i2c_slave_cb_t slave_cb; /* callback for slave mode */ #endif void *devres_group_id; /* ID of probe devres group */ }; #define to_i2c_client(d) container_of(d, struct i2c_client, dev) struct i2c_adapter *i2c_verify_adapter(struct device *dev); const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, const struct i2c_client *client); const void *i2c_get_match_data(const struct i2c_client *client); static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj) { struct device * const dev = kobj_to_dev(kobj); return to_i2c_client(dev); } static inline void *i2c_get_clientdata(const struct i2c_client *client) { return dev_get_drvdata(&client->dev); } static inline void i2c_set_clientdata(struct i2c_client *client, void *data) { dev_set_drvdata(&client->dev, data); } /* I2C slave support */ enum i2c_slave_event { I2C_SLAVE_READ_REQUESTED, I2C_SLAVE_WRITE_REQUESTED, I2C_SLAVE_READ_PROCESSED, I2C_SLAVE_WRITE_RECEIVED, I2C_SLAVE_STOP, }; int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb); int i2c_slave_unregister(struct i2c_client *client); int i2c_slave_event(struct i2c_client *client, enum i2c_slave_event event, u8 *val); #if IS_ENABLED(CONFIG_I2C_SLAVE) bool i2c_detect_slave_mode(struct device *dev); #else static inline bool i2c_detect_slave_mode(struct device *dev) { return false; } #endif /** * struct i2c_board_info - template for device creation * @type: chip type, to initialize i2c_client.name * @flags: to initialize i2c_client.flags * @addr: stored in i2c_client.addr * @dev_name: Overrides the default <busnr>-<addr> dev_name if set * @platform_data: stored in i2c_client.dev.platform_data * @of_node: pointer to OpenFirmware device node * @fwnode: device node supplied by the platform firmware * @swnode: software node for the device * @resources: resources associated with the device * @num_resources: number of resources in the @resources array * @irq: stored in i2c_client.irq * * I2C doesn't actually support hardware probing, although controllers and * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's * a device at a given address. Drivers commonly need more information than * that, such as chip type, configuration, associated IRQ, and so on. * * i2c_board_info is used to build tables of information listing I2C devices * that are present. This information is used to grow the driver model tree. * For mainboards this is done statically using i2c_register_board_info(); * bus numbers identify adapters that aren't yet available. For add-on boards, * i2c_new_client_device() does this dynamically with the adapter already known. */ struct i2c_board_info { char type[I2C_NAME_SIZE]; unsigned short flags; unsigned short addr; const char *dev_name; void *platform_data; struct device_node *of_node; struct fwnode_handle *fwnode; const struct software_node *swnode; const struct resource *resources; unsigned int num_resources; int irq; }; /** * I2C_BOARD_INFO - macro used to list an i2c device and its address * @dev_type: identifies the device type * @dev_addr: the device's address on the bus. * * This macro initializes essential fields of a struct i2c_board_info, * declaring what has been provided on a particular board. Optional * fields (such as associated irq, or device-specific platform_data) * are provided using conventional syntax. */ #define I2C_BOARD_INFO(dev_type, dev_addr) \ .type = dev_type, .addr = (dev_addr) #if IS_ENABLED(CONFIG_I2C) /* * Add-on boards should register/unregister their devices; e.g. a board * with integrated I2C, a config eeprom, sensors, and a codec that's * used in conjunction with the primary hardware. */ struct i2c_client * i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info); /* If you don't know the exact address of an I2C device, use this variant * instead, which can probe for device presence in a list of possible * addresses. The "probe" callback function is optional. If it is provided, * it must return 1 on successful probe, 0 otherwise. If it is not provided, * a default probing method is used. */ struct i2c_client * i2c_new_scanned_device(struct i2c_adapter *adap, struct i2c_board_info *info, unsigned short const *addr_list, int (*probe)(struct i2c_adapter *adap, unsigned short addr)); /* Common custom probe functions */ int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr); struct i2c_client * i2c_new_dummy_device(struct i2c_adapter *adapter, u16 address); struct i2c_client * devm_i2c_new_dummy_device(struct device *dev, struct i2c_adapter *adap, u16 address); struct i2c_client * i2c_new_ancillary_device(struct i2c_client *client, const char *name, u16 default_addr); void i2c_unregister_device(struct i2c_client *client); struct i2c_client *i2c_verify_client(struct device *dev); #else static inline struct i2c_client *i2c_verify_client(struct device *dev) { return NULL; } #endif /* I2C */ /* Mainboard arch_initcall() code should register all its I2C devices. * This is done at arch_initcall time, before declaring any i2c adapters. * Modules for add-on boards must use other calls. */ #ifdef CONFIG_I2C_BOARDINFO int i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned n); #else static inline int i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned n) { return 0; } #endif /* I2C_BOARDINFO */ /** * struct i2c_algorithm - represent I2C transfer method * @master_xfer: Issue a set of i2c transactions to the given I2C adapter * defined by the msgs array, with num messages available to transfer via * the adapter specified by adap. * @master_xfer_atomic: same as @master_xfer. Yet, only using atomic context * so e.g. PMICs can be accessed very late before shutdown. Optional. * @smbus_xfer: Issue smbus transactions to the given I2C adapter. If this * is not present, then the bus layer will try and convert the SMBus calls * into I2C transfers instead. * @smbus_xfer_atomic: same as @smbus_xfer. Yet, only using atomic context * so e.g. PMICs can be accessed very late before shutdown. Optional. * @functionality: Return the flags that this algorithm/adapter pair supports * from the ``I2C_FUNC_*`` flags. * @reg_slave: Register given client to I2C slave mode of this adapter * @unreg_slave: Unregister given client from I2C slave mode of this adapter * * The following structs are for those who like to implement new bus drivers: * i2c_algorithm is the interface to a class of hardware solutions which can * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 * to name two of the most common. * * The return codes from the ``master_xfer{_atomic}`` fields should indicate the * type of error code that occurred during the transfer, as documented in the * Kernel Documentation file Documentation/i2c/fault-codes.rst. Otherwise, the * number of messages executed should be returned. */ struct i2c_algorithm { /* * If an adapter algorithm can't do I2C-level access, set master_xfer * to NULL. If an adapter algorithm can do SMBus access, set * smbus_xfer. If set to NULL, the SMBus protocol is simulated * using common I2C messages. * * master_xfer should return the number of messages successfully * processed, or a negative value on error */ int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); int (*master_xfer_atomic)(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); int (*smbus_xfer)(struct i2c_adapter *adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data); int (*smbus_xfer_atomic)(struct i2c_adapter *adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data); /* To determine what the adapter supports */ u32 (*functionality)(struct i2c_adapter *adap); #if IS_ENABLED(CONFIG_I2C_SLAVE) int (*reg_slave)(struct i2c_client *client); int (*unreg_slave)(struct i2c_client *client); #endif }; /** * struct i2c_lock_operations - represent I2C locking operations * @lock_bus: Get exclusive access to an I2C bus segment * @trylock_bus: Try to get exclusive access to an I2C bus segment * @unlock_bus: Release exclusive access to an I2C bus segment * * The main operations are wrapped by i2c_lock_bus and i2c_unlock_bus. */ struct i2c_lock_operations { void (*lock_bus)(struct i2c_adapter *adapter, unsigned int flags); int (*trylock_bus)(struct i2c_adapter *adapter, unsigned int flags); void (*unlock_bus)(struct i2c_adapter *adapter, unsigned int flags); }; /** * struct i2c_timings - I2C timing information * @bus_freq_hz: the bus frequency in Hz * @scl_rise_ns: time SCL signal takes to rise in ns; t(r) in the I2C specification * @scl_fall_ns: time SCL signal takes to fall in ns; t(f) in the I2C specification * @scl_int_delay_ns: time IP core additionally needs to setup SCL in ns * @sda_fall_ns: time SDA signal takes to fall in ns; t(f) in the I2C specification * @sda_hold_ns: time IP core additionally needs to hold SDA in ns * @digital_filter_width_ns: width in ns of spikes on i2c lines that the IP core * digital filter can filter out * @analog_filter_cutoff_freq_hz: threshold frequency for the low pass IP core * analog filter */ struct i2c_timings { u32 bus_freq_hz; u32 scl_rise_ns; u32 scl_fall_ns; u32 scl_int_delay_ns; u32 sda_fall_ns; u32 sda_hold_ns; u32 digital_filter_width_ns; u32 analog_filter_cutoff_freq_hz; }; /** * struct i2c_bus_recovery_info - I2C bus recovery information * @recover_bus: Recover routine. Either pass driver's recover_bus() routine, or * i2c_generic_scl_recovery(). * @get_scl: This gets current value of SCL line. Mandatory for generic SCL * recovery. Populated internally for generic GPIO recovery. * @set_scl: This sets/clears the SCL line. Mandatory for generic SCL recovery. * Populated internally for generic GPIO recovery. * @get_sda: This gets current value of SDA line. This or set_sda() is mandatory * for generic SCL recovery. Populated internally, if sda_gpio is a valid * GPIO, for generic GPIO recovery. * @set_sda: This sets/clears the SDA line. This or get_sda() is mandatory for * generic SCL recovery. Populated internally, if sda_gpio is a valid GPIO, * for generic GPIO recovery. * @get_bus_free: Returns the bus free state as seen from the IP core in case it * has a more complex internal logic than just reading SDA. Optional. * @prepare_recovery: This will be called before starting recovery. Platform may * configure padmux here for SDA/SCL line or something else they want. * @unprepare_recovery: This will be called after completing recovery. Platform * may configure padmux here for SDA/SCL line or something else they want. * @scl_gpiod: gpiod of the SCL line. Only required for GPIO recovery. * @sda_gpiod: gpiod of the SDA line. Only required for GPIO recovery. * @pinctrl: pinctrl used by GPIO recovery to change the state of the I2C pins. * Optional. * @pins_default: default pinctrl state of SCL/SDA lines, when they are assigned * to the I2C bus. Optional. Populated internally for GPIO recovery, if * state with the name PINCTRL_STATE_DEFAULT is found and pinctrl is valid. * @pins_gpio: recovery pinctrl state of SCL/SDA lines, when they are used as * GPIOs. Optional. Populated internally for GPIO recovery, if this state * is called "gpio" or "recovery" and pinctrl is valid. */ struct i2c_bus_recovery_info { int (*recover_bus)(struct i2c_adapter *adap); int (*get_scl)(struct i2c_adapter *adap); void (*set_scl)(struct i2c_adapter *adap, int val); int (*get_sda)(struct i2c_adapter *adap); void (*set_sda)(struct i2c_adapter *adap, int val); int (*get_bus_free)(struct i2c_adapter *adap); void (*prepare_recovery)(struct i2c_adapter *adap); void (*unprepare_recovery)(struct i2c_adapter *adap); /* gpio recovery */ struct gpio_desc *scl_gpiod; struct gpio_desc *sda_gpiod; struct pinctrl *pinctrl; struct pinctrl_state *pins_default; struct pinctrl_state *pins_gpio; }; int i2c_recover_bus(struct i2c_adapter *adap); /* Generic recovery routines */ int i2c_generic_scl_recovery(struct i2c_adapter *adap); /** * struct i2c_adapter_quirks - describe flaws of an i2c adapter * @flags: see I2C_AQ_* for possible flags and read below * @max_num_msgs: maximum number of messages per transfer * @max_write_len: maximum length of a write message * @max_read_len: maximum length of a read message * @max_comb_1st_msg_len: maximum length of the first msg in a combined message * @max_comb_2nd_msg_len: maximum length of the second msg in a combined message * * Note about combined messages: Some I2C controllers can only send one message * per transfer, plus something called combined message or write-then-read. * This is (usually) a small write message followed by a read message and * barely enough to access register based devices like EEPROMs. There is a flag * to support this mode. It implies max_num_msg = 2 and does the length checks * with max_comb_*_len because combined message mode usually has its own * limitations. Because of HW implementations, some controllers can actually do * write-then-anything or other variants. To support that, write-then-read has * been broken out into smaller bits like write-first and read-second which can * be combined as needed. */ struct i2c_adapter_quirks { u64 flags; int max_num_msgs; u16 max_write_len; u16 max_read_len; u16 max_comb_1st_msg_len; u16 max_comb_2nd_msg_len; }; /* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */ #define I2C_AQ_COMB BIT(0) /* first combined message must be write */ #define I2C_AQ_COMB_WRITE_FIRST BIT(1) /* second combined message must be read */ #define I2C_AQ_COMB_READ_SECOND BIT(2) /* both combined messages must have the same target address */ #define I2C_AQ_COMB_SAME_ADDR BIT(3) /* convenience macro for typical write-then read case */ #define I2C_AQ_COMB_WRITE_THEN_READ (I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | \ I2C_AQ_COMB_READ_SECOND | I2C_AQ_COMB_SAME_ADDR) /* clock stretching is not supported */ #define I2C_AQ_NO_CLK_STRETCH BIT(4) /* message cannot have length of 0 */ #define I2C_AQ_NO_ZERO_LEN_READ BIT(5) #define I2C_AQ_NO_ZERO_LEN_WRITE BIT(6) #define I2C_AQ_NO_ZERO_LEN (I2C_AQ_NO_ZERO_LEN_READ | I2C_AQ_NO_ZERO_LEN_WRITE) /* adapter cannot do repeated START */ #define I2C_AQ_NO_REP_START BIT(7) /* * i2c_adapter is the structure used to identify a physical i2c bus along * with the access algorithms necessary to access it. */ struct i2c_adapter { struct module *owner; unsigned int class; /* classes to allow probing for */ const struct i2c_algorithm *algo; /* the algorithm to access the bus */ void *algo_data; /* data fields that are valid for all devices */ const struct i2c_lock_operations *lock_ops; struct rt_mutex bus_lock; struct rt_mutex mux_lock; int timeout; /* in jiffies */ int retries; struct device dev; /* the adapter device */ unsigned long locked_flags; /* owned by the I2C core */ #define I2C_ALF_IS_SUSPENDED 0 #define I2C_ALF_SUSPEND_REPORTED 1 int nr; char name[48]; struct completion dev_released; struct mutex userspace_clients_lock; struct list_head userspace_clients; struct i2c_bus_recovery_info *bus_recovery_info; const struct i2c_adapter_quirks *quirks; struct irq_domain *host_notify_domain; struct regulator *bus_regulator; }; #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) static inline void *i2c_get_adapdata(const struct i2c_adapter *adap) { return dev_get_drvdata(&adap->dev); } static inline void i2c_set_adapdata(struct i2c_adapter *adap, void *data) { dev_set_drvdata(&adap->dev, data); } static inline struct i2c_adapter * i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter) { #if IS_ENABLED(CONFIG_I2C_MUX) struct device *parent = adapter->dev.parent; if (parent != NULL && parent->type == &i2c_adapter_type) return to_i2c_adapter(parent); else #endif return NULL; } int i2c_for_each_dev(void *data, int (*fn)(struct device *dev, void *data)); /* Adapter locking functions, exported for shared pin cases */ #define I2C_LOCK_ROOT_ADAPTER BIT(0) #define I2C_LOCK_SEGMENT BIT(1) /** * i2c_lock_bus - Get exclusive access to an I2C bus segment * @adapter: Target I2C bus segment * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT * locks only this branch in the adapter tree */ static inline void i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags) { adapter->lock_ops->lock_bus(adapter, flags); } /** * i2c_trylock_bus - Try to get exclusive access to an I2C bus segment * @adapter: Target I2C bus segment * @flags: I2C_LOCK_ROOT_ADAPTER tries to locks the root i2c adapter, * I2C_LOCK_SEGMENT tries to lock only this branch in the adapter tree * * Return: true if the I2C bus segment is locked, false otherwise */ static inline int i2c_trylock_bus(struct i2c_adapter *adapter, unsigned int flags) { return adapter->lock_ops->trylock_bus(adapter, flags); } /** * i2c_unlock_bus - Release exclusive access to an I2C bus segment * @adapter: Target I2C bus segment * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT * unlocks only this branch in the adapter tree */ static inline void i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) { adapter->lock_ops->unlock_bus(adapter, flags); } /** * i2c_mark_adapter_suspended - Report suspended state of the adapter to the core * @adap: Adapter to mark as suspended * * When using this helper to mark an adapter as suspended, the core will reject * further transfers to this adapter. The usage of this helper is optional but * recommended for devices having distinct handlers for system suspend and * runtime suspend. More complex devices are free to implement custom solutions * to reject transfers when suspended. */ static inline void i2c_mark_adapter_suspended(struct i2c_adapter *adap) { i2c_lock_bus(adap, I2C_LOCK_ROOT_ADAPTER); set_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags); i2c_unlock_bus(adap, I2C_LOCK_ROOT_ADAPTER); } /** * i2c_mark_adapter_resumed - Report resumed state of the adapter to the core * @adap: Adapter to mark as resumed * * When using this helper to mark an adapter as resumed, the core will allow * further transfers to this adapter. See also further notes to * @i2c_mark_adapter_suspended(). */ static inline void i2c_mark_adapter_resumed(struct i2c_adapter *adap) { i2c_lock_bus(adap, I2C_LOCK_ROOT_ADAPTER); clear_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags); i2c_unlock_bus(adap, I2C_LOCK_ROOT_ADAPTER); } /* i2c adapter classes (bitmask) */ #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ #define I2C_CLASS_SPD (1<<7) /* Memory modules */ /* Warn users that the adapter doesn't support classes anymore */ #define I2C_CLASS_DEPRECATED (1<<8) /* Internal numbers to terminate lists */ #define I2C_CLIENT_END 0xfffeU /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */ #define I2C_ADDRS(addr, addrs...) \ ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END }) /* ----- functions exported by i2c.o */ /* administration... */ #if IS_ENABLED(CONFIG_I2C) int i2c_add_adapter(struct i2c_adapter *adap); int devm_i2c_add_adapter(struct device *dev, struct i2c_adapter *adapter); void i2c_del_adapter(struct i2c_adapter *adap); int i2c_add_numbered_adapter(struct i2c_adapter *adap); int i2c_register_driver(struct module *owner, struct i2c_driver *driver); void i2c_del_driver(struct i2c_driver *driver); /* use a define to avoid include chaining to get THIS_MODULE */ #define i2c_add_driver(driver) \ i2c_register_driver(THIS_MODULE, driver) static inline bool i2c_client_has_driver(struct i2c_client *client) { return !IS_ERR_OR_NULL(client) && client->dev.driver; } /* call the i2c_client->command() of all attached clients with * the given arguments */ void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg); struct i2c_adapter *i2c_get_adapter(int nr); void i2c_put_adapter(struct i2c_adapter *adap); unsigned int i2c_adapter_depth(struct i2c_adapter *adapter); void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults); /* Return the functionality mask */ static inline u32 i2c_get_functionality(struct i2c_adapter *adap) { return adap->algo->functionality(adap); } /* Return 1 if adapter supports everything we need, 0 if not. */ static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func) { return (func & i2c_get_functionality(adap)) == func; } /** * i2c_check_quirks() - Function for checking the quirk flags in an i2c adapter * @adap: i2c adapter * @quirks: quirk flags * * Return: true if the adapter has all the specified quirk flags, false if not */ static inline bool i2c_check_quirks(struct i2c_adapter *adap, u64 quirks) { if (!adap->quirks) return false; return (adap->quirks->flags & quirks) == quirks; } /* Return the adapter number for a specific adapter */ static inline int i2c_adapter_id(struct i2c_adapter *adap) { return adap->nr; } static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg) { return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0); } u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold); void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred); int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr); /** * module_i2c_driver() - Helper macro for registering a modular I2C driver * @__i2c_driver: i2c_driver struct * * Helper macro for I2C drivers which do not do anything special in module * init/exit. This eliminates a lot of boilerplate. Each module may only * use this macro once, and calling it replaces module_init() and module_exit() */ #define module_i2c_driver(__i2c_driver) \ module_driver(__i2c_driver, i2c_add_driver, \ i2c_del_driver) /** * builtin_i2c_driver() - Helper macro for registering a builtin I2C driver * @__i2c_driver: i2c_driver struct * * Helper macro for I2C drivers which do not do anything special in their * init. This eliminates a lot of boilerplate. Each driver may only * use this macro once, and calling it replaces device_initcall(). */ #define builtin_i2c_driver(__i2c_driver) \ builtin_driver(__i2c_driver, i2c_add_driver) #endif /* I2C */ /* must call put_device() when done with returned i2c_client device */ struct i2c_client *i2c_find_device_by_fwnode(struct fwnode_handle *fwnode); /* must call put_device() when done with returned i2c_adapter device */ struct i2c_adapter *i2c_find_adapter_by_fwnode(struct fwnode_handle *fwnode); /* must call i2c_put_adapter() when done with returned i2c_adapter device */ struct i2c_adapter *i2c_get_adapter_by_fwnode(struct fwnode_handle *fwnode); #if IS_ENABLED(CONFIG_OF) /* must call put_device() when done with returned i2c_client device */ static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) { return i2c_find_device_by_fwnode(of_fwnode_handle(node)); } /* must call put_device() when done with returned i2c_adapter device */ static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) { return i2c_find_adapter_by_fwnode(of_fwnode_handle(node)); } /* must call i2c_put_adapter() when done with returned i2c_adapter device */ static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) { return i2c_get_adapter_by_fwnode(of_fwnode_handle(node)); } const struct of_device_id *i2c_of_match_device(const struct of_device_id *matches, struct i2c_client *client); int of_i2c_get_board_info(struct device *dev, struct device_node *node, struct i2c_board_info *info); #else static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) { return NULL; } static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) { return NULL; } static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) { return NULL; } static inline const struct of_device_id *i2c_of_match_device(const struct of_device_id *matches, struct i2c_client *client) { return NULL; } static inline int of_i2c_get_board_info(struct device *dev, struct device_node *node, struct i2c_board_info *info) { return -ENOTSUPP; } #endif /* CONFIG_OF */ struct acpi_resource; struct acpi_resource_i2c_serialbus; #if IS_ENABLED(CONFIG_ACPI) bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, struct acpi_resource_i2c_serialbus **i2c); int i2c_acpi_client_count(struct acpi_device *adev); u32 i2c_acpi_find_bus_speed(struct device *dev); struct i2c_client *i2c_acpi_new_device_by_fwnode(struct fwnode_handle *fwnode, int index, struct i2c_board_info *info); struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle); bool i2c_acpi_waive_d0_probe(struct device *dev); #else static inline bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, struct acpi_resource_i2c_serialbus **i2c) { return false; } static inline int i2c_acpi_client_count(struct acpi_device *adev) { return 0; } static inline u32 i2c_acpi_find_bus_speed(struct device *dev) { return 0; } static inline struct i2c_client *i2c_acpi_new_device_by_fwnode( struct fwnode_handle *fwnode, int index, struct i2c_board_info *info) { return ERR_PTR(-ENODEV); } static inline struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle) { return NULL; } static inline bool i2c_acpi_waive_d0_probe(struct device *dev) { return false; } #endif /* CONFIG_ACPI */ static inline struct i2c_client *i2c_acpi_new_device(struct device *dev, int index, struct i2c_board_info *info) { return i2c_acpi_new_device_by_fwnode(dev_fwnode(dev), index, info); } #endif /* _LINUX_I2C_H */