diff options
Diffstat (limited to 'drivers/w1/w1_int.c')
| -rw-r--r-- | drivers/w1/w1_int.c | 109 |
1 files changed, 90 insertions, 19 deletions
diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c index 6840dfebe4d..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 @@ -23,13 +23,20 @@ #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); + +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, @@ -59,17 +66,24 @@ 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); + 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; @@ -91,11 +105,16 @@ 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) && @@ -105,9 +124,37 @@ int w1_add_master_device(struct w1_bus_master *master) 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; + } + + 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 +162,10 @@ 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 +176,13 @@ int w1_add_master_device(struct w1_bus_master *master) return 0; +#if 0 /* Thread cleanup code, not required currently. */ err_out_kill_thread: + 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); @@ -148,17 +192,40 @@ err_out_free_dev: void __w1_remove_master_device(struct w1_master *dev) { struct w1_netlink_msg msg; + struct w1_slave *sl, *sln; + + mutex_lock(&w1_mlock); + list_del(&dev->w1_master_entry); + mutex_unlock(&w1_mlock); - set_bit(W1_MASTER_NEED_EXIT, &dev->flags); + 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_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; @@ -168,6 +235,10 @@ void __w1_remove_master_device(struct w1_master *dev) 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, *found = NULL; |