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Diffstat (limited to 'include/linux/i3c/device.h')
| -rw-r--r-- | include/linux/i3c/device.h | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h new file mode 100644 index 000000000000..5ecb055fd375 --- /dev/null +++ b/include/linux/i3c/device.h @@ -0,0 +1,331 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2018 Cadence Design Systems Inc. + * + * Author: Boris Brezillon <boris.brezillon@bootlin.com> + */ + +#ifndef I3C_DEV_H +#define I3C_DEV_H + +#include <linux/bitops.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/kconfig.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> + +/** + * enum i3c_error_code - I3C error codes + * + * These are the standard error codes as defined by the I3C specification. + * When -EIO is returned by the i3c_device_do_priv_xfers() or + * i3c_device_send_hdr_cmds() one can check the error code in + * &struct_i3c_priv_xfer.err or &struct i3c_hdr_cmd.err to get a better idea of + * what went wrong. + * + * @I3C_ERROR_UNKNOWN: unknown error, usually means the error is not I3C + * related + * @I3C_ERROR_M0: M0 error + * @I3C_ERROR_M1: M1 error + * @I3C_ERROR_M2: M2 error + */ +enum i3c_error_code { + I3C_ERROR_UNKNOWN = 0, + I3C_ERROR_M0 = 1, + I3C_ERROR_M1, + I3C_ERROR_M2, +}; + +/** + * enum i3c_hdr_mode - HDR mode ids + * @I3C_HDR_DDR: DDR mode + * @I3C_HDR_TSP: TSP mode + * @I3C_HDR_TSL: TSL mode + */ +enum i3c_hdr_mode { + I3C_HDR_DDR, + I3C_HDR_TSP, + I3C_HDR_TSL, +}; + +/** + * struct i3c_priv_xfer - I3C SDR private transfer + * @rnw: encodes the transfer direction. true for a read, false for a write + * @len: transfer length in bytes of the transfer + * @data: input/output buffer + * @data.in: input buffer. Must point to a DMA-able buffer + * @data.out: output buffer. Must point to a DMA-able buffer + * @err: I3C error code + */ +struct i3c_priv_xfer { + u8 rnw; + u16 len; + union { + void *in; + const void *out; + } data; + enum i3c_error_code err; +}; + +/** + * enum i3c_dcr - I3C DCR values + * @I3C_DCR_GENERIC_DEVICE: generic I3C device + */ +enum i3c_dcr { + I3C_DCR_GENERIC_DEVICE = 0, +}; + +#define I3C_PID_MANUF_ID(pid) (((pid) & GENMASK_ULL(47, 33)) >> 33) +#define I3C_PID_RND_LOWER_32BITS(pid) (!!((pid) & BIT_ULL(32))) +#define I3C_PID_RND_VAL(pid) ((pid) & GENMASK_ULL(31, 0)) +#define I3C_PID_PART_ID(pid) (((pid) & GENMASK_ULL(31, 16)) >> 16) +#define I3C_PID_INSTANCE_ID(pid) (((pid) & GENMASK_ULL(15, 12)) >> 12) +#define I3C_PID_EXTRA_INFO(pid) ((pid) & GENMASK_ULL(11, 0)) + +#define I3C_BCR_DEVICE_ROLE(bcr) ((bcr) & GENMASK(7, 6)) +#define I3C_BCR_I3C_SLAVE (0 << 6) +#define I3C_BCR_I3C_MASTER (1 << 6) +#define I3C_BCR_HDR_CAP BIT(5) +#define I3C_BCR_BRIDGE BIT(4) +#define I3C_BCR_OFFLINE_CAP BIT(3) +#define I3C_BCR_IBI_PAYLOAD BIT(2) +#define I3C_BCR_IBI_REQ_CAP BIT(1) +#define I3C_BCR_MAX_DATA_SPEED_LIM BIT(0) + +/** + * struct i3c_device_info - I3C device information + * @pid: Provisional ID + * @bcr: Bus Characteristic Register + * @dcr: Device Characteristic Register + * @static_addr: static/I2C address + * @dyn_addr: dynamic address + * @hdr_cap: supported HDR modes + * @max_read_ds: max read speed information + * @max_write_ds: max write speed information + * @max_ibi_len: max IBI payload length + * @max_read_turnaround: max read turn-around time in micro-seconds + * @max_read_len: max private SDR read length in bytes + * @max_write_len: max private SDR write length in bytes + * + * These are all basic information that should be advertised by an I3C device. + * Some of them are optional depending on the device type and device + * capabilities. + * For each I3C slave attached to a master with + * i3c_master_add_i3c_dev_locked(), the core will send the relevant CCC command + * to retrieve these data. + */ +struct i3c_device_info { + u64 pid; + u8 bcr; + u8 dcr; + u8 static_addr; + u8 dyn_addr; + u8 hdr_cap; + u8 max_read_ds; + u8 max_write_ds; + u8 max_ibi_len; + u32 max_read_turnaround; + u16 max_read_len; + u16 max_write_len; +}; + +/* + * I3C device internals are kept hidden from I3C device users. It's just + * simpler to refactor things when everything goes through getter/setters, and + * I3C device drivers should not have to worry about internal representation + * anyway. + */ +struct i3c_device; + +/* These macros should be used to i3c_device_id entries. */ +#define I3C_MATCH_MANUF_AND_PART (I3C_MATCH_MANUF | I3C_MATCH_PART) + +#define I3C_DEVICE(_manufid, _partid, _drvdata) \ + { \ + .match_flags = I3C_MATCH_MANUF_AND_PART, \ + .manuf_id = _manufid, \ + .part_id = _partid, \ + .data = _drvdata, \ + } + +#define I3C_DEVICE_EXTRA_INFO(_manufid, _partid, _info, _drvdata) \ + { \ + .match_flags = I3C_MATCH_MANUF_AND_PART | \ + I3C_MATCH_EXTRA_INFO, \ + .manuf_id = _manufid, \ + .part_id = _partid, \ + .extra_info = _info, \ + .data = _drvdata, \ + } + +#define I3C_CLASS(_dcr, _drvdata) \ + { \ + .match_flags = I3C_MATCH_DCR, \ + .dcr = _dcr, \ + } + +/** + * struct i3c_driver - I3C device driver + * @driver: inherit from device_driver + * @probe: I3C device probe method + * @remove: I3C device remove method + * @id_table: I3C device match table. Will be used by the framework to decide + * which device to bind to this driver + */ +struct i3c_driver { + struct device_driver driver; + int (*probe)(struct i3c_device *dev); + int (*remove)(struct i3c_device *dev); + const struct i3c_device_id *id_table; +}; + +static inline struct i3c_driver *drv_to_i3cdrv(struct device_driver *drv) +{ + return container_of(drv, struct i3c_driver, driver); +} + +struct device *i3cdev_to_dev(struct i3c_device *i3cdev); +struct i3c_device *dev_to_i3cdev(struct device *dev); + +static inline void i3cdev_set_drvdata(struct i3c_device *i3cdev, + void *data) +{ + struct device *dev = i3cdev_to_dev(i3cdev); + + dev_set_drvdata(dev, data); +} + +static inline void *i3cdev_get_drvdata(struct i3c_device *i3cdev) +{ + struct device *dev = i3cdev_to_dev(i3cdev); + + return dev_get_drvdata(dev); +} + +int i3c_driver_register_with_owner(struct i3c_driver *drv, + struct module *owner); +void i3c_driver_unregister(struct i3c_driver *drv); + +#define i3c_driver_register(__drv) \ + i3c_driver_register_with_owner(__drv, THIS_MODULE) + +/** + * module_i3c_driver() - Register a module providing an I3C driver + * @__drv: the I3C driver to register + * + * Provide generic init/exit functions that simply register/unregister an I3C + * driver. + * Should be used by any driver that does not require extra init/cleanup steps. + */ +#define module_i3c_driver(__drv) \ + module_driver(__drv, i3c_driver_register, i3c_driver_unregister) + +/** + * i3c_i2c_driver_register() - Register an i2c and an i3c driver + * @i3cdrv: the I3C driver to register + * @i2cdrv: the I2C driver to register + * + * This function registers both @i2cdev and @i3cdev, and fails if one of these + * registrations fails. This is mainly useful for devices that support both I2C + * and I3C modes. + * Note that when CONFIG_I3C is not enabled, this function only registers the + * I2C driver. + * + * Return: 0 if both registrations succeeds, a negative error code otherwise. + */ +static inline int i3c_i2c_driver_register(struct i3c_driver *i3cdrv, + struct i2c_driver *i2cdrv) +{ + int ret; + + ret = i2c_add_driver(i2cdrv); + if (ret || !IS_ENABLED(CONFIG_I3C)) + return ret; + + ret = i3c_driver_register(i3cdrv); + if (ret) + i2c_del_driver(i2cdrv); + + return ret; +} + +/** + * i3c_i2c_driver_unregister() - Unregister an i2c and an i3c driver + * @i3cdrv: the I3C driver to register + * @i2cdrv: the I2C driver to register + * + * This function unregisters both @i3cdrv and @i2cdrv. + * Note that when CONFIG_I3C is not enabled, this function only unregisters the + * @i2cdrv. + */ +static inline void i3c_i2c_driver_unregister(struct i3c_driver *i3cdrv, + struct i2c_driver *i2cdrv) +{ + if (IS_ENABLED(CONFIG_I3C)) + i3c_driver_unregister(i3cdrv); + + i2c_del_driver(i2cdrv); +} + +/** + * module_i3c_i2c_driver() - Register a module providing an I3C and an I2C + * driver + * @__i3cdrv: the I3C driver to register + * @__i2cdrv: the I3C driver to register + * + * Provide generic init/exit functions that simply register/unregister an I3C + * and an I2C driver. + * This macro can be used even if CONFIG_I3C is disabled, in this case, only + * the I2C driver will be registered. + * Should be used by any driver that does not require extra init/cleanup steps. + */ +#define module_i3c_i2c_driver(__i3cdrv, __i2cdrv) \ + module_driver(__i3cdrv, \ + i3c_i2c_driver_register, \ + i3c_i2c_driver_unregister) + +int i3c_device_do_priv_xfers(struct i3c_device *dev, + struct i3c_priv_xfer *xfers, + int nxfers); + +void i3c_device_get_info(struct i3c_device *dev, struct i3c_device_info *info); + +struct i3c_ibi_payload { + unsigned int len; + const void *data; +}; + +/** + * struct i3c_ibi_setup - IBI setup object + * @max_payload_len: maximum length of the payload associated to an IBI. If one + * IBI appears to have a payload that is bigger than this + * number, the IBI will be rejected. + * @num_slots: number of pre-allocated IBI slots. This should be chosen so that + * the system never runs out of IBI slots, otherwise you'll lose + * IBIs. + * @handler: IBI handler, every time an IBI is received. This handler is called + * in a workqueue context. It is allowed to sleep and send new + * messages on the bus, though it's recommended to keep the + * processing done there as fast as possible to avoid delaying + * processing of other queued on the same workqueue. + * + * Temporary structure used to pass information to i3c_device_request_ibi(). + * This object can be allocated on the stack since i3c_device_request_ibi() + * copies every bit of information and do not use it after + * i3c_device_request_ibi() has returned. + */ +struct i3c_ibi_setup { + unsigned int max_payload_len; + unsigned int num_slots; + void (*handler)(struct i3c_device *dev, + const struct i3c_ibi_payload *payload); +}; + +int i3c_device_request_ibi(struct i3c_device *dev, + const struct i3c_ibi_setup *setup); +void i3c_device_free_ibi(struct i3c_device *dev); +int i3c_device_enable_ibi(struct i3c_device *dev); +int i3c_device_disable_ibi(struct i3c_device *dev); + +#endif /* I3C_DEV_H */ |