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Diffstat (limited to 'kernel/drivers/w1/w1.h')
| -rw-r--r-- | kernel/drivers/w1/w1.h | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/kernel/drivers/w1/w1.h b/kernel/drivers/w1/w1.h new file mode 100644 index 000000000..56a49ba41 --- /dev/null +++ b/kernel/drivers/w1/w1.h @@ -0,0 +1,341 @@ +/* + * w1.h + * + * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef __W1_H +#define __W1_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__ + +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/mutex.h> + +#include "w1_family.h" + +#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_READ_SCRATCHPAD 0xBE +#define W1_READ_ROM 0x33 +#define W1_READ_PSUPPLY 0xB4 +#define W1_MATCH_ROM 0x55 +#define W1_RESUME_CMD 0xA5 + +#define W1_SLAVE_ACTIVE 0 +#define W1_SLAVE_DETACH 1 + +/** + * 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 + * + */ +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; +}; + +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 bytes. 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 handles 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 + * + * 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); +}; + +/** + * 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; +}; + +/** + * struct w1_async_cmd - execute callback from the w1_process kthread + * @async_entry: link entry + * @cb: callback function, must list_del and destroy this list before + * returning + * + * When inserted into the w1_master async_list, w1_process will execute + * the callback. Embed this into the structure with the command details. + */ +struct w1_async_cmd { + struct list_head async_entry; + void (*cb)(struct w1_master *dev, struct w1_async_cmd *async_cmd); +}; + +int w1_create_master_attributes(struct w1_master *); +void w1_destroy_master_attributes(struct w1_master *master); +void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb); +void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb); +/* call w1_unref_slave to release the reference counts w1_search_slave added */ +struct w1_slave *w1_search_slave(struct w1_reg_num *id); +/* decrements the reference on sl->master and sl, and cleans up if zero + * returns the reference count after it has been decremented */ +int w1_unref_slave(struct w1_slave *sl); +void w1_slave_found(struct w1_master *dev, u64 rn); +void w1_search_process_cb(struct w1_master *dev, u8 search_type, + w1_slave_found_callback cb); +struct w1_slave *w1_slave_search_device(struct w1_master *dev, + struct w1_reg_num *rn); +struct w1_master *w1_search_master_id(u32 id); + +/* Disconnect and reconnect devices in the given family. Used for finding + * unclaimed devices after a family has been registered or releasing devices + * after a family has been unregistered. Set attach to 1 when a new family + * has just been registered, to 0 when it has been unregistered. + */ +void w1_reconnect_slaves(struct w1_family *f, int attach); +int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn); +/* 0 success, otherwise EBUSY */ +int w1_slave_detach(struct w1_slave *sl); + +u8 w1_triplet(struct w1_master *dev, int bdir); +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); +} + +extern struct device_driver w1_master_driver; +extern struct device w1_master_device; +extern int w1_max_slave_count; +extern int w1_max_slave_ttl; +extern struct list_head w1_masters; +extern struct mutex w1_mlock; + +extern int w1_process_callbacks(struct w1_master *dev); +extern int w1_process(void *); + +#endif /* __KERNEL__ */ + +#endif /* __W1_H */ |