X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fw1%2Fw1_int.c;h=a3a54567bfba87f041b8d0735aa7d96996a604d8;hb=8113587c2d14d3be2414190845b2e2617c0aa33b;hp=ed3228017dad0fa89813f071b84fe4803e4413d2;hpb=c30c9b15187e977ab5928f7276e9dfcd8d6f9460;p=linux-2.6-omap-h63xx.git

diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c
index ed3228017da..a3a54567bfb 100644
--- a/drivers/w1/w1_int.c
+++ b/drivers/w1/w1_int.c
@@ -29,7 +29,11 @@
 #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);
+
+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,
@@ -59,8 +63,12 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 	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);
@@ -93,9 +101,10 @@ static void w1_free_dev(struct w1_master *dev)
 
 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) &&
@@ -104,10 +113,50 @@ int w1_add_master_device(struct w1_bus_master *master)
 		printk(KERN_ERR "w1_add_master_device: invalid function set\n");
 		return(-EINVAL);
         }
+	/* While it would be electrically possible to make a device that
+	 * generated a strong pullup in bit bang mode, only hardare that
+	 * controls 1-wire time frames are even expected to support a strong
+	 * pullup.  w1_io.c would need to support calling set_pullup before
+	 * the last write_bit operation of a w1_write_8 which it currently
+	 * doesn't.
+	 */
+	if (!master->write_byte && !master->touch_bit && master->set_pullup) {
+		printk(KERN_ERR "w1_add_master_device: set_pullup requires "
+			"write_byte or touch_bit, disabling\n");
+		master->set_pullup = NULL;
+	}
+
+	/* 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(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_master_driver, &w1_master_device);
-	if (!dev)
+	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;
+	}
+
+	retval =  w1_create_master_attributes(dev);
+	if (retval) {
+		mutex_unlock(&w1_mlock);
+		goto err_out_free_dev;
+	}
+
+	memcpy(dev->bus_master, master, sizeof(struct w1_bus_master));
+
+	dev->initialized = 1;
 
 	dev->thread = kthread_run(&w1_process, dev, "%s", dev->name);
 	if (IS_ERR(dev->thread)) {
@@ -115,18 +164,10 @@ int w1_add_master_device(struct w1_bus_master *master)
 		dev_err(&dev->dev,
 			 "Failed to create new kernel thread. err=%d\n",
 			 retval);
-		goto err_out_free_dev;
+		mutex_unlock(&w1_mlock);
+		goto err_out_rm_attr;
 	}
 
-	retval =  w1_create_master_attributes(dev);
-	if (retval)
-		goto err_out_kill_thread;
-
-	memcpy(dev->bus_master, master, sizeof(struct w1_bus_master));
-
-	dev->initialized = 1;
-
-	mutex_lock(&w1_mlock);
 	list_add(&dev->w1_master_entry, &w1_masters);
 	mutex_unlock(&w1_mlock);
 
@@ -137,8 +178,12 @@ int w1_add_master_device(struct w1_bus_master *master)
 
 	return 0;
 
+#if 0 /* Thread cleanup code, not required currently. */
 err_out_kill_thread:
 	kthread_stop(dev->thread);
+#endif
+err_out_rm_attr:
+	w1_destroy_master_attributes(dev);
 err_out_free_dev:
 	w1_free_dev(dev);
 
@@ -150,7 +195,6 @@ void __w1_remove_master_device(struct w1_master *dev)
 	struct w1_netlink_msg msg;
 	struct w1_slave *sl, *sln;
 
-	set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
 	kthread_stop(dev->thread);
 
 	mutex_lock(&w1_mlock);