diff options
Diffstat (limited to 'drivers/w1/w1.h')
| -rw-r--r-- | drivers/w1/w1.h | 186 |
1 files changed, 143 insertions, 43 deletions
diff --git a/drivers/w1/w1.h b/drivers/w1/w1.h index ca8081a101d..734dab7fc68 100644 --- a/drivers/w1/w1.h +++ b/drivers/w1/w1.h @@ -22,6 +22,13 @@ #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) @@ -58,7 +65,24 @@ struct w1_reg_num #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; @@ -66,7 +90,6 @@ struct w1_slave struct list_head w1_slave_entry; struct w1_reg_num reg_num; atomic_t refcnt; - u8 rom[9]; int ttl; unsigned long flags; @@ -74,99 +97,146 @@ struct w1_slave struct w1_family *family; void *family_data; struct device dev; - struct completion released; }; 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 { - /** the first parameter in all the functions below */ void *data; - /** - * Sample the line level - * @return the level read (0 or 1) - */ u8 (*read_bit)(void *); - /** Sets the line level */ void (*write_bit)(void *, u8); - /** - * touch_bit is 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) - */ u8 (*touch_bit)(void *, u8); - /** - * Reads a bytes. Same as 8 touch_bit(1) calls. - * @return the byte read - */ u8 (*read_byte)(void *); - /** - * Writes a byte. Same as 8 touch_bit(x) calls. - */ void (*write_byte)(void *, u8); - /** - * Same as a series of read_byte() calls - * @return the number of bytes read - */ u8 (*read_block)(void *, u8 *, int); - /** Same as a series of write_byte() calls */ void (*write_block)(void *, const u8 *, int); - /** - * Combines two reads and a smart write for ROM searches - * @return bit0=Id bit1=comp_id bit2=dir_taken - */ u8 (*triplet)(void *, u8); - /** - * long write-0 with a read for the presence pulse detection - * @return -1=Error, 0=Device present, 1=No device present - */ u8 (*reset_bus)(void *); - /** - * Put out a strong pull-up pulse of the specified duration. - * @return -1=Error, 0=completed - */ u8 (*set_pullup)(void *, int); - /** Really nice hardware can handles the different types of ROM search - * w1_master* is passed to the slave found callback. - */ 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 + * @priv_size: size allocated + * @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 + * @portid: destination for the current netlink command + */ 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; @@ -178,6 +248,8 @@ struct w1_master /** 5V strong pullup duration in milliseconds, zero disabled. */ int pullup_duration; + long flags; + struct task_struct *thread; struct mutex mutex; struct mutex bus_mutex; @@ -188,16 +260,41 @@ struct w1_master struct w1_bus_master *bus_master; u32 seq; + /* port id to send netlink responses to. The value is temporarily + * stored here while processing a message, set after locking the + * mutex, zero before unlocking the mutex. + */ + u32 portid; +}; + +/** + * 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 @@ -206,7 +303,9 @@ struct w1_master *w1_search_master_id(u32 id); * has just been registered, to 0 when it has been unregistered. */ void w1_reconnect_slaves(struct w1_family *f, int attach); -void w1_slave_detach(struct w1_slave *sl); +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); @@ -242,6 +341,7 @@ 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__ */ |