Before this patch 1-wire subsystem didn't provide access to its
add/remove events to other parts of the kernel. Now it is possible
to register a standard notifier_block observer, which will be informed
of subsequent device insertions and removals.
The framework is copied from USB subsystem.
Signed-off-by: Sergey Yanovich <[email protected]>
---
drivers/w1/Kconfig | 7 ++
drivers/w1/Makefile | 3 +-
drivers/w1/notify.c | 76 ++++++++++++++++++++
drivers/w1/w1.c | 2 +
drivers/w1/w1.h | 160 ++++--------------------------------------
drivers/w1/w1_int.c | 2 +
drivers/w1/w1_netlink.h | 11 +--
include/linux/w1.h | 176 +++++++++++++++++++++++++++++++++++++++++++++++
8 files changed, 279 insertions(+), 158 deletions(-)
create mode 100644 drivers/w1/notify.c
create mode 100644 include/linux/w1.h
diff --git a/drivers/w1/Kconfig b/drivers/w1/Kconfig
index 6743bde..d33d074 100644
--- a/drivers/w1/Kconfig
+++ b/drivers/w1/Kconfig
@@ -25,6 +25,13 @@ config W1_CON
2. Userspace commands. Includes read/write and search/alarm search commands.
3. Replies to userspace commands.
+config W1_NOTIFY
+ bool "Dallas's 1-wire device notifications"
+ default n
+ ---help---
+ This allows other parts of kernel to be notified of 1-wire hotplug
+ events.
+
source drivers/w1/masters/Kconfig
source drivers/w1/slaves/Kconfig
diff --git a/drivers/w1/Makefile b/drivers/w1/Makefile
index 6bb0b54..233ec84 100644
--- a/drivers/w1/Makefile
+++ b/drivers/w1/Makefile
@@ -3,7 +3,8 @@
#
obj-$(CONFIG_W1) += wire.o
-wire-objs := w1.o w1_int.o w1_family.o w1_netlink.o w1_io.o
+wire-objs := w1.o w1_int.o w1_family.o w1_netlink.o w1_io.o \
+ notify.o
obj-y += masters/ slaves/
diff --git a/drivers/w1/notify.c b/drivers/w1/notify.c
new file mode 100644
index 0000000..2b4a123
--- /dev/null
+++ b/drivers/w1/notify.c
@@ -0,0 +1,76 @@
+/*
+ * linux/drivers/w1/notify.c
+ *
+ * Notification logic for 1-wire subsystem
+ *
+ * (C) Copyright 2013 Sergey Yanovich
+ *
+ * This is mostly a copy with s/usb/w1/gc from
+ * linux/drivers/usb/notify.c
+ *
+ * All the USB notify logic
+ *
+ * (C) Copyright 2005 Greg Kroah-Hartman <[email protected]>
+ *
+ * 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.
+ */
+
+#ifdef CONFIG_W1_NOTIFY
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/notifier.h>
+#include <linux/w1.h>
+#include <linux/mutex.h>
+#include "w1.h"
+
+static BLOCKING_NOTIFIER_HEAD(w1_notifier_list);
+
+/**
+ * w1_register_notify - register a notifier callback whenever a w1 change happens
+ * @nb: pointer to the notifier block for the callback events.
+ *
+ * These changes are either w1 devices or busses being added or removed.
+ */
+void w1_register_notify(struct notifier_block *nb)
+{
+ blocking_notifier_chain_register(&w1_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(w1_register_notify);
+
+/**
+ * w1_unregister_notify - unregister a notifier callback
+ * @nb: pointer to the notifier block for the callback events.
+ *
+ * w1_register_notify() must have been previously called for this function
+ * to work properly.
+ */
+void w1_unregister_notify(struct notifier_block *nb)
+{
+ blocking_notifier_chain_unregister(&w1_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(w1_unregister_notify);
+
+void w1_notify_add_slave(struct w1_slave *dev)
+{
+ blocking_notifier_call_chain(&w1_notifier_list, W1_SLAVE_ADD, dev);
+}
+
+void w1_notify_remove_slave(struct w1_slave *dev)
+{
+ blocking_notifier_call_chain(&w1_notifier_list, W1_SLAVE_REMOVE, dev);
+}
+
+void w1_notify_add_master(struct w1_master *bus)
+{
+ blocking_notifier_call_chain(&w1_notifier_list, W1_MASTER_ADD, bus);
+}
+
+void w1_notify_remove_master(struct w1_master *bus)
+{
+ blocking_notifier_call_chain(&w1_notifier_list, W1_MASTER_REMOVE, bus);
+}
+#endif
diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 7994d933..f546005 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -709,6 +709,7 @@ static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
memcpy(msg.id.id, rn, sizeof(msg.id));
msg.type = W1_SLAVE_ADD;
w1_netlink_send(dev, &msg);
+ w1_notify_add_slave(sl);
return 0;
}
@@ -728,6 +729,7 @@ void w1_slave_detach(struct w1_slave *sl)
memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id));
msg.type = W1_SLAVE_REMOVE;
w1_netlink_send(sl->master, &msg);
+ w1_notify_remove_slave(sl);
device_remove_file(&sl->dev, &w1_slave_attr_id);
device_remove_file(&sl->dev, &w1_slave_attr_name);
diff --git a/drivers/w1/w1.h b/drivers/w1/w1.h
index 45908e5..a600e35 100644
--- a/drivers/w1/w1.h
+++ b/drivers/w1/w1.h
@@ -22,31 +22,15 @@
#ifndef __W1_H
#define __W1_H
-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
-};
+#include <linux/w1.h>
#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
@@ -59,136 +43,6 @@ struct w1_reg_num
#define W1_SLAVE_ACTIVE 0
-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;
- u8 rom[9];
- u32 flags;
- int ttl;
-
- struct w1_master *master;
- struct w1_family *family;
- void *family_data;
- struct device dev;
- struct completion released;
-};
-
-typedef void (*w1_slave_found_callback)(struct w1_master *, u64);
-
-
-/**
- * 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);
-};
-
-struct w1_master
-{
- struct list_head w1_master_entry;
- struct module *owner;
- unsigned char name[W1_MAXNAMELEN];
- struct list_head slist;
- int max_slave_count, slave_count;
- unsigned long attempts;
- int slave_ttl;
- int initialized;
- u32 id;
- int search_count;
-
- atomic_t refcnt;
-
- void *priv;
- int priv_size;
-
- /** 5V strong pullup enabled flag, 1 enabled, zero disabled. */
- int enable_pullup;
- /** 5V strong pullup duration in milliseconds, zero disabled. */
- int pullup_duration;
-
- 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_create_master_attributes(struct w1_master *);
void w1_destroy_master_attributes(struct w1_master *master);
@@ -244,6 +98,18 @@ extern struct mutex w1_mlock;
extern int w1_process(void *);
+#ifdef CONFIG_W1_NOTIFY
+void w1_notify_add_slave(struct w1_slave *dev);
+void w1_notify_remove_slave(struct w1_slave *dev);
+void w1_notify_add_master(struct w1_master *bus);
+void w1_notify_remove_master(struct w1_master *bus);
+#else /* !CONFIG_W1_NOTIFY */
+static inline void w1_notify_add_slave(struct w1_slave *dev) {}
+static inline void w1_notify_remove_slave(struct w1_slave *dev) {}
+static inline void w1_notify_add_master(struct w1_master *bus) {}
+static inline void w1_notify_remove_master(struct w1_master *bus) {}
+#endif /* CONFIG_W1_NOTIFY */
+
#endif /* __KERNEL__ */
#endif /* __W1_H */
diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c
index 5a98649..279dacb 100644
--- a/drivers/w1/w1_int.c
+++ b/drivers/w1/w1_int.c
@@ -179,6 +179,7 @@ int w1_add_master_device(struct w1_bus_master *master)
msg.id.mst.id = dev->id;
msg.type = W1_MASTER_ADD;
w1_netlink_send(dev, &msg);
+ w1_notify_add_master(dev);
return 0;
@@ -224,6 +225,7 @@ void __w1_remove_master_device(struct w1_master *dev)
msg.id.mst.id = dev->id;
msg.type = W1_MASTER_REMOVE;
w1_netlink_send(dev, &msg);
+ w1_notify_remove_master(dev);
w1_free_dev(dev);
}
diff --git a/drivers/w1/w1_netlink.h b/drivers/w1/w1_netlink.h
index b0922dc..ef4b0fb 100644
--- a/drivers/w1/w1_netlink.h
+++ b/drivers/w1/w1_netlink.h
@@ -25,18 +25,9 @@
#include <asm/types.h>
#include <linux/connector.h>
+#include <linux/w1.h>
#include "w1.h"
-enum w1_netlink_message_types {
- W1_SLAVE_ADD = 0,
- W1_SLAVE_REMOVE,
- W1_MASTER_ADD,
- W1_MASTER_REMOVE,
- W1_MASTER_CMD,
- W1_SLAVE_CMD,
- W1_LIST_MASTERS,
-};
-
struct w1_netlink_msg
{
__u8 type;
diff --git a/include/linux/w1.h b/include/linux/w1.h
new file mode 100644
index 0000000..6b4a9af
--- /dev/null
+++ b/include/linux/w1.h
@@ -0,0 +1,176 @@
+#ifndef __LINUX_W1_H
+#define __LINUX_W1_H
+
+/* 64-bit 1-Wire device ID */
+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
+};
+
+/* Events from the w1 core */
+enum w1_netlink_message_types {
+ W1_SLAVE_ADD = 0,
+ W1_SLAVE_REMOVE,
+ W1_MASTER_ADD,
+ W1_MASTER_REMOVE,
+ W1_MASTER_CMD,
+ W1_SLAVE_CMD,
+ W1_LIST_MASTERS,
+};
+
+#ifdef __KERNEL__
+
+#include <linux/device.h>
+
+#define W1_MAXNAMELEN 32
+
+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;
+ u8 rom[9];
+ u32 flags;
+ int ttl;
+
+ struct w1_master *master;
+ struct w1_family *family;
+ void *family_data;
+ struct device dev;
+ struct completion released;
+};
+
+typedef void (*w1_slave_found_callback)(struct w1_master *, u64);
+
+/**
+ * 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);
+};
+
+struct w1_master
+{
+ struct list_head w1_master_entry;
+ struct module *owner;
+ unsigned char name[W1_MAXNAMELEN];
+ struct list_head slist;
+ int max_slave_count, slave_count;
+ unsigned long attempts;
+ int slave_ttl;
+ int initialized;
+ u32 id;
+ int search_count;
+
+ atomic_t refcnt;
+
+ void *priv;
+ int priv_size;
+
+ /** 5V strong pullup enabled flag, 1 enabled, zero disabled. */
+ int enable_pullup;
+ /** 5V strong pullup duration in milliseconds, zero disabled. */
+ int pullup_duration;
+
+ 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;
+};
+
+#ifdef CONFIG_W1_NOTIFY
+
+extern void w1_register_notify(struct notifier_block *nb);
+extern void w1_unregister_notify(struct notifier_block *nb);
+
+#endif /* CONFIG_W1_NOTIFY */
+
+#endif /* __KERNEL__ */
+
+#endif /* __LINUX_W1_H */
--
1.7.10.4
On Fri, Mar 22, 2013 at 10:15:29PM +0400, Sergey Yanovich ([email protected]) wrote:
> Before this patch 1-wire subsystem didn't provide access to its
> add/remove events to other parts of the kernel. Now it is possible
> to register a standard notifier_block observer, which will be informed
> of subsequent device insertions and removals.
>
> The framework is copied from USB subsystem.
>
> Signed-off-by: Sergey Yanovich <[email protected]>
Thanks Sergey, patch looks good to me
Acked-by: Evgeniy Polyakov <[email protected]>
Greg, please pull it into your tree.
Thank you
--
Evgeniy Polyakov