/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> */ #ifndef __LINUX_W1_H #define __LINUX_W1_H #include <linux/device.h> /** * struct w1_reg_num - broken out slave device id * * @family: identifies the type of device * @id: along with family is the unique device id * @crc: checksum of the other bytes */ struct w1_reg_num { #if defined(__LITTLE_ENDIAN_BITFIELD) __u64 family:8, id:48, crc:8; #elif defined(__BIG_ENDIAN_BITFIELD) __u64 crc:8, id:48, family:8; #else #error "Please fix <asm/byteorder.h>" #endif }; #ifdef __KERNEL__ #define W1_MAXNAMELEN 32 #define W1_SEARCH 0xF0 #define W1_ALARM_SEARCH 0xEC #define W1_CONVERT_TEMP 0x44 #define W1_SKIP_ROM 0xCC #define W1_COPY_SCRATCHPAD 0x48 #define W1_WRITE_SCRATCHPAD 0x4E #define W1_READ_SCRATCHPAD 0xBE #define W1_READ_ROM 0x33 #define W1_READ_PSUPPLY 0xB4 #define W1_MATCH_ROM 0x55 #define W1_RESUME_CMD 0xA5 /** * struct w1_slave - holds a single slave device on the bus * * @owner: Points to the one wire "wire" kernel module. * @name: Device id is ascii. * @w1_slave_entry: data for the linked list * @reg_num: the slave id in binary * @refcnt: reference count, delete when 0 * @flags: bit flags for W1_SLAVE_ACTIVE W1_SLAVE_DETACH * @ttl: decrement per search this slave isn't found, deatch at 0 * @master: bus which this slave is on * @family: module for device family type * @family_data: pointer for use by the family module * @dev: kernel device identifier * @hwmon: pointer to hwmon device * */ struct w1_slave { struct module *owner; unsigned char name[W1_MAXNAMELEN]; struct list_head w1_slave_entry; struct w1_reg_num reg_num; atomic_t refcnt; int ttl; unsigned long flags; struct w1_master *master; struct w1_family *family; void *family_data; struct device dev; struct device *hwmon; }; typedef void (*w1_slave_found_callback)(struct w1_master *, u64); /** * struct w1_bus_master - operations available on a bus master * * @data: the first parameter in all the functions below * * @read_bit: Sample the line level * @return the level read (0 or 1) * * @write_bit: Sets the line level * * @touch_bit: the lowest-level function for devices that really support the * 1-wire protocol. * touch_bit(0) = write-0 cycle * touch_bit(1) = write-1 / read cycle * @return the bit read (0 or 1) * * @read_byte: Reads a byte. Same as 8 touch_bit(1) calls. * @return the byte read * * @write_byte: Writes a byte. Same as 8 touch_bit(x) calls. * * @read_block: Same as a series of read_byte() calls * @return the number of bytes read * * @write_block: Same as a series of write_byte() calls * * @triplet: Combines two reads and a smart write for ROM searches * @return bit0=Id bit1=comp_id bit2=dir_taken * * @reset_bus: long write-0 with a read for the presence pulse detection * @return -1=Error, 0=Device present, 1=No device present * * @set_pullup: Put out a strong pull-up pulse of the specified duration. * @return -1=Error, 0=completed * * @search: Really nice hardware can handle the different types of ROM search * w1_master* is passed to the slave found callback. * u8 is search_type, W1_SEARCH or W1_ALARM_SEARCH * * @dev_id: Optional device id string, which w1 slaves could use for * creating names, which then give a connection to the w1 master * * Note: read_bit and write_bit are very low level functions and should only * be used with hardware that doesn't really support 1-wire operations, * like a parallel/serial port. * Either define read_bit and write_bit OR define, at minimum, touch_bit and * reset_bus. * */ struct w1_bus_master { void *data; u8 (*read_bit)(void *); void (*write_bit)(void *, u8); u8 (*touch_bit)(void *, u8); u8 (*read_byte)(void *); void (*write_byte)(void *, u8); u8 (*read_block)(void *, u8 *, int); void (*write_block)(void *, const u8 *, int); u8 (*triplet)(void *, u8); u8 (*reset_bus)(void *); u8 (*set_pullup)(void *, int); void (*search)(void *, struct w1_master *, u8, w1_slave_found_callback); char *dev_id; }; /** * enum w1_master_flags - bitfields used in w1_master.flags * @W1_ABORT_SEARCH: abort searching early on shutdown * @W1_WARN_MAX_COUNT: limit warning when the maximum count is reached */ enum w1_master_flags { W1_ABORT_SEARCH = 0, W1_WARN_MAX_COUNT = 1, }; /** * struct w1_master - one per bus master * @w1_master_entry: master linked list * @owner: module owner * @name: dynamically allocate bus name * @list_mutex: protect slist and async_list * @slist: linked list of slaves * @async_list: linked list of netlink commands to execute * @max_slave_count: maximum number of slaves to search for at a time * @slave_count: current number of slaves known * @attempts: number of searches ran * @slave_ttl: number of searches before a slave is timed out * @initialized: prevent init/removal race conditions * @id: w1 bus number * @search_count: number of automatic searches to run, -1 unlimited * @search_id: allows continuing a search * @refcnt: reference count * @priv: private data storage * @enable_pullup: allows a strong pullup * @pullup_duration: time for the next strong pullup * @flags: one of w1_master_flags * @thread: thread for bus search and netlink commands * @mutex: protect most of w1_master * @bus_mutex: pretect concurrent bus access * @driver: sysfs driver * @dev: sysfs device * @bus_master: io operations available * @seq: sequence number used for netlink broadcasts */ struct w1_master { struct list_head w1_master_entry; struct module *owner; unsigned char name[W1_MAXNAMELEN]; /* list_mutex protects just slist and async_list so slaves can be * searched for and async commands added while the master has * w1_master.mutex locked and is operating on the bus. * lock order w1_mlock, w1_master.mutex, w1_master.list_mutex */ struct mutex list_mutex; struct list_head slist; struct list_head async_list; int max_slave_count, slave_count; unsigned long attempts; int slave_ttl; int initialized; u32 id; int search_count; /* id to start searching on, to continue a search or 0 to restart */ u64 search_id; atomic_t refcnt; void *priv; /** 5V strong pullup enabled flag, 1 enabled, zero disabled. */ int enable_pullup; /** 5V strong pullup duration in milliseconds, zero disabled. */ int pullup_duration; long flags; struct task_struct *thread; struct mutex mutex; struct mutex bus_mutex; struct device_driver *driver; struct device dev; struct w1_bus_master *bus_master; u32 seq; }; int w1_add_master_device(struct w1_bus_master *master); void w1_remove_master_device(struct w1_bus_master *master); /** * struct w1_family_ops - operations for a family type * @add_slave: add_slave * @remove_slave: remove_slave * @groups: sysfs group * @chip_info: pointer to struct hwmon_chip_info */ struct w1_family_ops { int (*add_slave)(struct w1_slave *sl); void (*remove_slave)(struct w1_slave *sl); const struct attribute_group **groups; const struct hwmon_chip_info *chip_info; }; /** * struct w1_family - reference counted family structure. * @family_entry: family linked list * @fid: 8 bit family identifier * @fops: operations for this family * @of_match_table: open firmware match table * @refcnt: reference counter */ struct w1_family { struct list_head family_entry; u8 fid; const struct w1_family_ops *fops; const struct of_device_id *of_match_table; atomic_t refcnt; }; int w1_register_family(struct w1_family *family); void w1_unregister_family(struct w1_family *family); /** * module_w1_family() - Helper macro for registering a 1-Wire families * @__w1_family: w1_family struct * * Helper macro for 1-Wire families 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_w1_family(__w1_family) \ module_driver(__w1_family, w1_register_family, \ w1_unregister_family) u8 w1_triplet(struct w1_master *dev, int bdir); u8 w1_touch_bit(struct w1_master *dev, int bit); void w1_write_8(struct w1_master *, u8); u8 w1_read_8(struct w1_master *); int w1_reset_bus(struct w1_master *); u8 w1_calc_crc8(u8 *, int); void w1_write_block(struct w1_master *, const u8 *, int); void w1_touch_block(struct w1_master *, u8 *, int); u8 w1_read_block(struct w1_master *, u8 *, int); int w1_reset_select_slave(struct w1_slave *sl); int w1_reset_resume_command(struct w1_master *); void w1_next_pullup(struct w1_master *, int); static inline struct w1_slave* dev_to_w1_slave(struct device *dev) { return container_of(dev, struct w1_slave, dev); } static inline struct w1_slave* kobj_to_w1_slave(struct kobject *kobj) { return dev_to_w1_slave(container_of(kobj, struct device, kobj)); } static inline struct w1_master* dev_to_w1_master(struct device *dev) { return container_of(dev, struct w1_master, dev); } #endif /* __KERNEL__ */ #endif /* __LINUX_W1_H */
