--- /dev/null
+/*
+ * 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 */
Code Review / kvmfornfv.git / blobdiff