| /* 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); |
| #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 - soon to be deprecated |
| * @probe_new: New 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, const struct i2c_device_id *id); |
| int (*remove)(struct i2c_client *client); |
| |
| /* New driver model interface to aid the seamless removal of the |
| * current probe()'s, more commonly unused than used second parameter. |
| */ |
| int (*probe_new)(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); |
| |
| 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 */ |
| |
| #if IS_ENABLED(CONFIG_I2C_SLAVE) |
| 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); |
| bool i2c_detect_slave_mode(struct device *dev); |
| |
| static inline int i2c_slave_event(struct i2c_client *client, |
| enum i2c_slave_event event, u8 *val) |
| { |
| return client->slave_cb(client, event, val); |
| } |
| #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. |
| */ |
| 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 */ |
| |
| #if IS_ENABLED(CONFIG_OF) |
| /* must call put_device() when done with returned i2c_client device */ |
| struct i2c_client *of_find_i2c_device_by_node(struct device_node *node); |
| |
| /* must call put_device() when done with returned i2c_adapter device */ |
| struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node); |
| |
| /* must call i2c_put_adapter() when done with returned i2c_adapter device */ |
| struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *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(struct device *dev, 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(struct device *dev, |
| 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 */ |
| |
| #endif /* _LINUX_I2C_H */ |