1 files changed, 109 insertions, 65 deletions

diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c
index c3f67eafc7e..728039d2efe 100644
--- a/drivers/w1/w1_int.c
+++ b/drivers/w1/w1_int.c
@@ -1,7 +1,7 @@
 /*
  *	w1_int.c
  *
- * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+ * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
  *
  *
  * This program is free software; you can redistribute it and/or modify
@@ -22,22 +22,21 @@
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/moduleparam.h>
 
 #include "w1.h"
 #include "w1_log.h"
 #include "w1_netlink.h"
+#include "w1_int.h"
 
-static u32 w1_ids = 1;
+static int w1_search_count = -1; /* Default is continual scan */
+module_param_named(search_count, w1_search_count, int, 0);
 
-extern struct device_driver w1_master_driver;
-extern struct bus_type w1_bus_type;
-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 spinlock_t w1_mlock;
-
-extern int w1_process(void *);
+static int w1_enable_pullup = 1;
+module_param_named(enable_pullup, w1_enable_pullup, int, 0);
 
 static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 				       struct device_driver *driver,
@@ -49,7 +48,7 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 	/*
 	 * We are in process context(kernel thread), so can sleep.
 	 */
-	dev = kmalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL);
+	dev = kzalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL);
 	if (!dev) {
 		printk(KERN_ERR
 			"Failed to allocate %zd bytes for new w1 device.\n",
@@ -57,7 +56,6 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 		return NULL;
 	}
 
-	memset(dev, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master));
 
 	dev->bus_master = (struct w1_bus_master *)(dev + 1);
 
@@ -65,36 +63,35 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 	dev->max_slave_count	= slave_count;
 	dev->slave_count	= 0;
 	dev->attempts		= 0;
-	dev->kpid		= -1;
 	dev->initialized	= 0;
 	dev->id			= id;
 	dev->slave_ttl		= slave_ttl;
-        dev->search_count	= -1; /* continual scan */
+	dev->search_count	= w1_search_count;
+	dev->enable_pullup	= w1_enable_pullup;
 
+	/* 1 for w1_process to decrement
+	 * 1 for __w1_remove_master_device to decrement
+	 */
 	atomic_set(&dev->refcnt, 2);
 
 	INIT_LIST_HEAD(&dev->slist);
-	init_MUTEX(&dev->mutex);
-
-	init_completion(&dev->dev_exited);
+	INIT_LIST_HEAD(&dev->async_list);
+	mutex_init(&dev->mutex);
+	mutex_init(&dev->bus_mutex);
+	mutex_init(&dev->list_mutex);
 
 	memcpy(&dev->dev, device, sizeof(struct device));
-	snprintf(dev->dev.bus_id, sizeof(dev->dev.bus_id),
-		  "w1_bus_master%u", dev->id);
+	dev_set_name(&dev->dev, "w1_bus_master%u", dev->id);
 	snprintf(dev->name, sizeof(dev->name), "w1_bus_master%u", dev->id);
+	dev->dev.init_name = dev->name;
 
 	dev->driver = driver;
 
-	dev->groups = 1;
 	dev->seq = 1;
-	dev_init_netlink(dev);
 
 	err = device_register(&dev->dev);
 	if (err) {
 		printk(KERN_ERR "Failed to register master device. err=%d\n", err);
-
-		dev_fini_netlink(dev);
-
 		memset(dev, 0, sizeof(struct w1_master));
 		kfree(dev);
 		dev = NULL;
@@ -103,64 +100,89 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 	return dev;
 }
 
-void w1_free_dev(struct w1_master *dev)
+static void w1_free_dev(struct w1_master *dev)
 {
 	device_unregister(&dev->dev);
 }
 
+/**
+ * w1_add_master_device() - registers a new master device
+ * @master:	master bus device to register
+ */
 int w1_add_master_device(struct w1_bus_master *master)
 {
-	struct w1_master *dev;
+	struct w1_master *dev, *entry;
 	int retval = 0;
 	struct w1_netlink_msg msg;
+	int id, found;
 
         /* validate minimum functionality */
         if (!(master->touch_bit && master->reset_bus) &&
-            !(master->write_bit && master->read_bit)) {
+            !(master->write_bit && master->read_bit) &&
+	    !(master->write_byte && master->read_byte && master->reset_bus)) {
 		printk(KERN_ERR "w1_add_master_device: invalid function set\n");
 		return(-EINVAL);
         }
 
-	dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_master_driver, &w1_master_device);
-	if (!dev)
+	/* Lock until the device is added (or not) to w1_masters. */
+	mutex_lock(&w1_mlock);
+	/* Search for the first available id (starting at 1). */
+	id = 0;
+	do {
+		++id;
+		found = 0;
+		list_for_each_entry(entry, &w1_masters, w1_master_entry) {
+			if (entry->id == id) {
+				found = 1;
+				break;
+			}
+		}
+	} while (found);
+
+	dev = w1_alloc_dev(id, w1_max_slave_count, w1_max_slave_ttl,
+		&w1_master_driver, &w1_master_device);
+	if (!dev) {
+		mutex_unlock(&w1_mlock);
 		return -ENOMEM;
-
-	dev->kpid = kernel_thread(&w1_process, dev, 0);
-	if (dev->kpid < 0) {
-		dev_err(&dev->dev,
-			 "Failed to create new kernel thread. err=%d\n",
-			 dev->kpid);
-		retval = dev->kpid;
-		goto err_out_free_dev;
 	}
 
 	retval =  w1_create_master_attributes(dev);
-	if (retval)
-		goto err_out_kill_thread;
+	if (retval) {
+		mutex_unlock(&w1_mlock);
+		goto err_out_free_dev;
+	}
 
 	memcpy(dev->bus_master, master, sizeof(struct w1_bus_master));
 
 	dev->initialized = 1;
 
-	spin_lock(&w1_mlock);
+	dev->thread = kthread_run(&w1_process, dev, "%s", dev->name);
+	if (IS_ERR(dev->thread)) {
+		retval = PTR_ERR(dev->thread);
+		dev_err(&dev->dev,
+			 "Failed to create new kernel thread. err=%d\n",
+			 retval);
+		mutex_unlock(&w1_mlock);
+		goto err_out_rm_attr;
+	}
+
 	list_add(&dev->w1_master_entry, &w1_masters);
-	spin_unlock(&w1_mlock);
+	mutex_unlock(&w1_mlock);
 
+	memset(&msg, 0, sizeof(msg));
 	msg.id.mst.id = dev->id;
-	msg.id.mst.pid = dev->kpid;
 	msg.type = W1_MASTER_ADD;
 	w1_netlink_send(dev, &msg);
 
 	return 0;
 
+#if 0 /* Thread cleanup code, not required currently. */
 err_out_kill_thread:
-	set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
-	if (kill_proc(dev->kpid, SIGTERM, 1))
-		dev_err(&dev->dev,
-			 "Failed to send signal to w1 kernel thread %d.\n",
-			 dev->kpid);
-	wait_for_completion(&dev->dev_exited);
-
+	set_bit(W1_ABORT_SEARCH, &dev->flags);
+	kthread_stop(dev->thread);
+#endif
+err_out_rm_attr:
+	w1_destroy_master_attributes(dev);
 err_out_free_dev:
 	w1_free_dev(dev);
 
@@ -169,53 +191,75 @@ err_out_free_dev:
 
 void __w1_remove_master_device(struct w1_master *dev)
 {
-	int err;
 	struct w1_netlink_msg msg;
+	struct w1_slave *sl, *sln;
 
-	set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
-	err = kill_proc(dev->kpid, SIGTERM, 1);
-	if (err)
-		dev_err(&dev->dev,
-			 "%s: Failed to send signal to w1 kernel thread %d.\n",
-			 __func__, dev->kpid);
+	mutex_lock(&w1_mlock);
+	list_del(&dev->w1_master_entry);
+	mutex_unlock(&w1_mlock);
+
+	set_bit(W1_ABORT_SEARCH, &dev->flags);
+	kthread_stop(dev->thread);
+
+	mutex_lock(&dev->mutex);
+	mutex_lock(&dev->list_mutex);
+	list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
+		mutex_unlock(&dev->list_mutex);
+		w1_slave_detach(sl);
+		mutex_lock(&dev->list_mutex);
+	}
+	w1_destroy_master_attributes(dev);
+	mutex_unlock(&dev->list_mutex);
+	mutex_unlock(&dev->mutex);
+	atomic_dec(&dev->refcnt);
 
 	while (atomic_read(&dev->refcnt)) {
-		dev_dbg(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n",
+		dev_info(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n",
 				dev->name, atomic_read(&dev->refcnt));
 
 		if (msleep_interruptible(1000))
 			flush_signals(current);
+		mutex_lock(&dev->list_mutex);
+		w1_process_callbacks(dev);
+		mutex_unlock(&dev->list_mutex);
 	}
+	mutex_lock(&dev->list_mutex);
+	w1_process_callbacks(dev);
+	mutex_unlock(&dev->list_mutex);
 
+	memset(&msg, 0, sizeof(msg));
 	msg.id.mst.id = dev->id;
-	msg.id.mst.pid = dev->kpid;
 	msg.type = W1_MASTER_REMOVE;
 	w1_netlink_send(dev, &msg);
 
 	w1_free_dev(dev);
 }
 
+/**
+ * w1_remove_master_device() - unregister a master device
+ * @bm:	master bus device to remove
+ */
 void w1_remove_master_device(struct w1_bus_master *bm)
 {
-	struct w1_master *dev = NULL;
+	struct w1_master *dev, *found = NULL;
 
 	list_for_each_entry(dev, &w1_masters, w1_master_entry) {
 		if (!dev->initialized)
 			continue;
 
-		if (dev->bus_master->data == bm->data)
+		if (dev->bus_master->data == bm->data) {
+			found = dev;
 			break;
+		}
 	}
 
-	if (!dev) {
+	if (!found) {
 		printk(KERN_ERR "Device doesn't exist.\n");
 		return;
 	}
 
-	__w1_remove_master_device(dev);
+	__w1_remove_master_device(found);
 }
 
 EXPORT_SYMBOL(w1_add_master_device);
 EXPORT_SYMBOL(w1_remove_master_device);
-
-MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_W1);