diff options
Diffstat (limited to 'drivers/w1/w1.c')
-rw-r--r-- | drivers/w1/w1.c | 423 |
1 files changed, 251 insertions, 172 deletions
diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 7293c9b11f91..3b615d4022ee 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -46,19 +46,17 @@ MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>"); MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol."); static int w1_timeout = 10; -static int w1_control_timeout = 1; int w1_max_slave_count = 10; int w1_max_slave_ttl = 10; module_param_named(timeout, w1_timeout, int, 0); -module_param_named(control_timeout, w1_control_timeout, int, 0); module_param_named(max_slave_count, w1_max_slave_count, int, 0); module_param_named(slave_ttl, w1_max_slave_ttl, int, 0); DEFINE_MUTEX(w1_mlock); LIST_HEAD(w1_masters); -static struct task_struct *w1_control_thread; +static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn); static int w1_master_match(struct device *dev, struct device_driver *drv) { @@ -83,10 +81,10 @@ static void w1_slave_release(struct device *dev) { struct w1_slave *sl = dev_to_w1_slave(dev); - printk("%s: Releasing %s.\n", __func__, sl->name); + dev_dbg(dev, "%s: Releasing %s.\n", __func__, sl->name); while (atomic_read(&sl->refcnt)) { - printk("Waiting for %s to become free: refcnt=%d.\n", + dev_dbg(dev, "Waiting for %s to become free: refcnt=%d.\n", sl->name, atomic_read(&sl->refcnt)); if (msleep_interruptible(1000)) flush_signals(current); @@ -105,35 +103,20 @@ static ssize_t w1_slave_read_name(struct device *dev, struct device_attribute *a return sprintf(buf, "%s\n", sl->name); } -static ssize_t w1_slave_read_id(struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t off, size_t count) +static ssize_t w1_slave_read_id(struct device *dev, + struct device_attribute *attr, char *buf) { - struct w1_slave *sl = kobj_to_w1_slave(kobj); - - if (off > 8) { - count = 0; - } else { - if (off + count > 8) - count = 8 - off; - - memcpy(buf, (u8 *)&sl->reg_num, count); - } + struct w1_slave *sl = dev_to_w1_slave(dev); + ssize_t count = sizeof(sl->reg_num); + memcpy(buf, (u8 *)&sl->reg_num, count); return count; } static struct device_attribute w1_slave_attr_name = __ATTR(name, S_IRUGO, w1_slave_read_name, NULL); - -static struct bin_attribute w1_slave_attr_bin_id = { - .attr = { - .name = "id", - .mode = S_IRUGO, - }, - .size = 8, - .read = w1_slave_read_id, -}; +static struct device_attribute w1_slave_attr_id = + __ATTR(id, S_IRUGO, w1_slave_read_id, NULL); /* Default family */ @@ -250,11 +233,16 @@ static ssize_t w1_master_attribute_store_search(struct device * dev, struct device_attribute *attr, const char * buf, size_t count) { + long tmp; struct w1_master *md = dev_to_w1_master(dev); + if (strict_strtol(buf, 0, &tmp) == -EINVAL) + return -EINVAL; + mutex_lock(&md->mutex); - md->search_count = simple_strtol(buf, NULL, 0); + md->search_count = tmp; mutex_unlock(&md->mutex); + wake_up_process(md->thread); return count; } @@ -273,6 +261,38 @@ static ssize_t w1_master_attribute_show_search(struct device *dev, return count; } +static ssize_t w1_master_attribute_store_pullup(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + long tmp; + struct w1_master *md = dev_to_w1_master(dev); + + if (strict_strtol(buf, 0, &tmp) == -EINVAL) + return -EINVAL; + + mutex_lock(&md->mutex); + md->enable_pullup = tmp; + mutex_unlock(&md->mutex); + wake_up_process(md->thread); + + return count; +} + +static ssize_t w1_master_attribute_show_pullup(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct w1_master *md = dev_to_w1_master(dev); + ssize_t count; + + mutex_lock(&md->mutex); + count = sprintf(buf, "%d\n", md->enable_pullup); + mutex_unlock(&md->mutex); + + return count; +} + static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); @@ -324,7 +344,8 @@ static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct d return count; } -static ssize_t w1_master_attribute_show_slaves(struct device *dev, struct device_attribute *attr, char *buf) +static ssize_t w1_master_attribute_show_slaves(struct device *dev, + struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); int c = PAGE_SIZE; @@ -349,6 +370,135 @@ static ssize_t w1_master_attribute_show_slaves(struct device *dev, struct device return PAGE_SIZE - c; } +static ssize_t w1_master_attribute_show_add(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int c = PAGE_SIZE; + c -= snprintf(buf+PAGE_SIZE - c, c, + "write device id xx-xxxxxxxxxxxx to add slave\n"); + return PAGE_SIZE - c; +} + +static int w1_atoreg_num(struct device *dev, const char *buf, size_t count, + struct w1_reg_num *rn) +{ + unsigned int family; + unsigned long long id; + int i; + u64 rn64_le; + + /* The CRC value isn't read from the user because the sysfs directory + * doesn't include it and most messages from the bus search don't + * print it either. It would be unreasonable for the user to then + * provide it. + */ + const char *error_msg = "bad slave string format, expecting " + "ff-dddddddddddd\n"; + + if (buf[2] != '-') { + dev_err(dev, "%s", error_msg); + return -EINVAL; + } + i = sscanf(buf, "%02x-%012llx", &family, &id); + if (i != 2) { + dev_err(dev, "%s", error_msg); + return -EINVAL; + } + rn->family = family; + rn->id = id; + + rn64_le = cpu_to_le64(*(u64 *)rn); + rn->crc = w1_calc_crc8((u8 *)&rn64_le, 7); + +#if 0 + dev_info(dev, "With CRC device is %02x.%012llx.%02x.\n", + rn->family, (unsigned long long)rn->id, rn->crc); +#endif + + return 0; +} + +/* Searches the slaves in the w1_master and returns a pointer or NULL. + * Note: must hold the mutex + */ +static struct w1_slave *w1_slave_search_device(struct w1_master *dev, + struct w1_reg_num *rn) +{ + struct w1_slave *sl; + list_for_each_entry(sl, &dev->slist, w1_slave_entry) { + if (sl->reg_num.family == rn->family && + sl->reg_num.id == rn->id && + sl->reg_num.crc == rn->crc) { + return sl; + } + } + return NULL; +} + +static ssize_t w1_master_attribute_store_add(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct w1_master *md = dev_to_w1_master(dev); + struct w1_reg_num rn; + struct w1_slave *sl; + ssize_t result = count; + + if (w1_atoreg_num(dev, buf, count, &rn)) + return -EINVAL; + + mutex_lock(&md->mutex); + sl = w1_slave_search_device(md, &rn); + /* It would be nice to do a targeted search one the one-wire bus + * for the new device to see if it is out there or not. But the + * current search doesn't support that. + */ + if (sl) { + dev_info(dev, "Device %s already exists\n", sl->name); + result = -EINVAL; + } else { + w1_attach_slave_device(md, &rn); + } + mutex_unlock(&md->mutex); + + return result; +} + +static ssize_t w1_master_attribute_show_remove(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int c = PAGE_SIZE; + c -= snprintf(buf+PAGE_SIZE - c, c, + "write device id xx-xxxxxxxxxxxx to remove slave\n"); + return PAGE_SIZE - c; +} + +static ssize_t w1_master_attribute_store_remove(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct w1_master *md = dev_to_w1_master(dev); + struct w1_reg_num rn; + struct w1_slave *sl; + ssize_t result = count; + + if (w1_atoreg_num(dev, buf, count, &rn)) + return -EINVAL; + + mutex_lock(&md->mutex); + sl = w1_slave_search_device(md, &rn); + if (sl) { + w1_slave_detach(sl); + } else { + dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family, + (unsigned long long)rn.id); + result = -EINVAL; + } + mutex_unlock(&md->mutex); + + return result; +} + #define W1_MASTER_ATTR_RO(_name, _mode) \ struct device_attribute w1_master_attribute_##_name = \ __ATTR(w1_master_##_name, _mode, \ @@ -368,6 +518,9 @@ static W1_MASTER_ATTR_RO(attempts, S_IRUGO); static W1_MASTER_ATTR_RO(timeout, S_IRUGO); static W1_MASTER_ATTR_RO(pointer, S_IRUGO); static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUGO); +static W1_MASTER_ATTR_RW(pullup, S_IRUGO | S_IWUGO); +static W1_MASTER_ATTR_RW(add, S_IRUGO | S_IWUGO); +static W1_MASTER_ATTR_RW(remove, S_IRUGO | S_IWUGO); static struct attribute *w1_master_default_attrs[] = { &w1_master_attribute_name.attr, @@ -378,6 +531,9 @@ static struct attribute *w1_master_default_attrs[] = { &w1_master_attribute_timeout.attr, &w1_master_attribute_pointer.attr, &w1_master_attribute_search.attr, + &w1_master_attribute_pullup.attr, + &w1_master_attribute_add.attr, + &w1_master_attribute_remove.attr, NULL }; @@ -390,7 +546,7 @@ int w1_create_master_attributes(struct w1_master *master) return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group); } -static void w1_destroy_master_attributes(struct w1_master *master) +void w1_destroy_master_attributes(struct w1_master *master) { sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group); } @@ -479,7 +635,7 @@ static int __w1_attach_slave_device(struct w1_slave *sl) } /* Create "id" entry */ - err = sysfs_create_bin_file(&sl->dev.kobj, &w1_slave_attr_bin_id); + err = device_create_file(&sl->dev, &w1_slave_attr_id); if (err < 0) { dev_err(&sl->dev, "sysfs file creation for [%s] failed. err=%d\n", @@ -501,7 +657,7 @@ static int __w1_attach_slave_device(struct w1_slave *sl) return 0; out_rem2: - sysfs_remove_bin_file(&sl->dev.kobj, &w1_slave_attr_bin_id); + device_remove_file(&sl->dev, &w1_slave_attr_id); out_rem1: device_remove_file(&sl->dev, &w1_slave_attr_name); out_unreg: @@ -567,7 +723,7 @@ static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) return 0; } -static void w1_slave_detach(struct w1_slave *sl) +void w1_slave_detach(struct w1_slave *sl) { struct w1_netlink_msg msg; @@ -583,7 +739,7 @@ static void w1_slave_detach(struct w1_slave *sl) msg.type = W1_SLAVE_REMOVE; w1_netlink_send(sl->master, &msg); - sysfs_remove_bin_file(&sl->dev.kobj, &w1_slave_attr_bin_id); + device_remove_file(&sl->dev, &w1_slave_attr_id); device_remove_file(&sl->dev, &w1_slave_attr_name); device_unregister(&sl->dev); @@ -591,24 +747,6 @@ static void w1_slave_detach(struct w1_slave *sl) kfree(sl); } -static struct w1_master *w1_search_master(void *data) -{ - struct w1_master *dev; - int found = 0; - - mutex_lock(&w1_mlock); - list_for_each_entry(dev, &w1_masters, w1_master_entry) { - if (dev->bus_master->data == data) { - found = 1; - atomic_inc(&dev->refcnt); - break; - } - } - mutex_unlock(&w1_mlock); - - return (found)?dev:NULL; -} - struct w1_master *w1_search_master_id(u32 id) { struct w1_master *dev; @@ -656,55 +794,56 @@ struct w1_slave *w1_search_slave(struct w1_reg_num *id) return (found)?sl:NULL; } -void w1_reconnect_slaves(struct w1_family *f) +void w1_reconnect_slaves(struct w1_family *f, int attach) { + struct w1_slave *sl, *sln; struct w1_master *dev; mutex_lock(&w1_mlock); list_for_each_entry(dev, &w1_masters, w1_master_entry) { - dev_dbg(&dev->dev, "Reconnecting slaves in %s into new family %02x.\n", - dev->name, f->fid); - set_bit(W1_MASTER_NEED_RECONNECT, &dev->flags); + dev_dbg(&dev->dev, "Reconnecting slaves in device %s " + "for family %02x.\n", dev->name, f->fid); + mutex_lock(&dev->mutex); + list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { + /* If it is a new family, slaves with the default + * family driver and are that family will be + * connected. If the family is going away, devices + * matching that family are reconneced. + */ + if ((attach && sl->family->fid == W1_FAMILY_DEFAULT + && sl->reg_num.family == f->fid) || + (!attach && sl->family->fid == f->fid)) { + struct w1_reg_num rn; + + memcpy(&rn, &sl->reg_num, sizeof(rn)); + w1_slave_detach(sl); + + w1_attach_slave_device(dev, &rn); + } + } + dev_dbg(&dev->dev, "Reconnecting slaves in device %s " + "has been finished.\n", dev->name); + mutex_unlock(&dev->mutex); } mutex_unlock(&w1_mlock); } -static void w1_slave_found(void *data, u64 rn) +static void w1_slave_found(struct w1_master *dev, u64 rn) { - int slave_count; struct w1_slave *sl; - struct list_head *ent; struct w1_reg_num *tmp; - struct w1_master *dev; u64 rn_le = cpu_to_le64(rn); - dev = w1_search_master(data); - if (!dev) { - printk(KERN_ERR "Failed to find w1 master device for data %p, " - "it is impossible.\n", data); - return; - } + atomic_inc(&dev->refcnt); tmp = (struct w1_reg_num *) &rn; - slave_count = 0; - list_for_each(ent, &dev->slist) { - - sl = list_entry(ent, struct w1_slave, w1_slave_entry); - - if (sl->reg_num.family == tmp->family && - sl->reg_num.id == tmp->id && - sl->reg_num.crc == tmp->crc) { - set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); - break; - } - - slave_count++; - } - - if (slave_count == dev->slave_count && - rn && ((rn >> 56) & 0xff) == w1_calc_crc8((u8 *)&rn_le, 7)) { - w1_attach_slave_device(dev, tmp); + sl = w1_slave_search_device(dev, tmp); + if (sl) { + set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); + } else { + if (rn && tmp->crc == w1_calc_crc8((u8 *)&rn_le, 7)) + w1_attach_slave_device(dev, tmp); } atomic_dec(&dev->refcnt); @@ -779,80 +918,20 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb /* extract the direction taken & update the device number */ tmp64 = (triplet_ret >> 2); rn |= (tmp64 << i); + + if (kthread_should_stop()) { + dev_dbg(&dev->dev, "Abort w1_search\n"); + return; + } } if ( (triplet_ret & 0x03) != 0x03 ) { if ( (desc_bit == last_zero) || (last_zero < 0)) last_device = 1; desc_bit = last_zero; - cb(dev->bus_master->data, rn); - } - } -} - -static int w1_control(void *data) -{ - struct w1_slave *sl, *sln; - struct w1_master *dev, *n; - int have_to_wait = 0; - - set_freezable(); - while (!kthread_should_stop() || have_to_wait) { - have_to_wait = 0; - - try_to_freeze(); - msleep_interruptible(w1_control_timeout * 1000); - - list_for_each_entry_safe(dev, n, &w1_masters, w1_master_entry) { - if (!kthread_should_stop() && !dev->flags) - continue; - /* - * Little race: we can create thread but not set the flag. - * Get a chance for external process to set flag up. - */ - if (!dev->initialized) { - have_to_wait = 1; - continue; - } - - if (kthread_should_stop() || test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) { - set_bit(W1_MASTER_NEED_EXIT, &dev->flags); - - mutex_lock(&w1_mlock); - list_del(&dev->w1_master_entry); - mutex_unlock(&w1_mlock); - - mutex_lock(&dev->mutex); - list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { - w1_slave_detach(sl); - } - w1_destroy_master_attributes(dev); - mutex_unlock(&dev->mutex); - atomic_dec(&dev->refcnt); - continue; - } - - if (test_bit(W1_MASTER_NEED_RECONNECT, &dev->flags)) { - dev_dbg(&dev->dev, "Reconnecting slaves in device %s.\n", dev->name); - mutex_lock(&dev->mutex); - list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { - if (sl->family->fid == W1_FAMILY_DEFAULT) { - struct w1_reg_num rn; - - memcpy(&rn, &sl->reg_num, sizeof(rn)); - w1_slave_detach(sl); - - w1_attach_slave_device(dev, &rn); - } - } - dev_dbg(&dev->dev, "Reconnecting slaves in device %s has been finished.\n", dev->name); - clear_bit(W1_MASTER_NEED_RECONNECT, &dev->flags); - mutex_unlock(&dev->mutex); - } + cb(dev, rn); } } - - return 0; } void w1_search_process(struct w1_master *dev, u8 search_type) @@ -878,23 +957,29 @@ void w1_search_process(struct w1_master *dev, u8 search_type) int w1_process(void *data) { struct w1_master *dev = (struct w1_master *) data; + /* As long as w1_timeout is only set by a module parameter the sleep + * time can be calculated in jiffies once. + */ + const unsigned long jtime = msecs_to_jiffies(w1_timeout * 1000); + + while (!kthread_should_stop()) { + if (dev->search_count) { + mutex_lock(&dev->mutex); + w1_search_process(dev, W1_SEARCH); + mutex_unlock(&dev->mutex); + } - while (!kthread_should_stop() && !test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) { try_to_freeze(); - msleep_interruptible(w1_timeout * 1000); + __set_current_state(TASK_INTERRUPTIBLE); - if (kthread_should_stop() || test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) + if (kthread_should_stop()) break; - if (!dev->initialized) - continue; - - if (dev->search_count == 0) - continue; - - mutex_lock(&dev->mutex); - w1_search_process(dev, W1_SEARCH); - mutex_unlock(&dev->mutex); + /* Only sleep when the search is active. */ + if (dev->search_count) + schedule_timeout(jtime); + else + schedule(); } atomic_dec(&dev->refcnt); @@ -932,18 +1017,13 @@ static int w1_init(void) goto err_out_master_unregister; } - w1_control_thread = kthread_run(w1_control, NULL, "w1_control"); - if (IS_ERR(w1_control_thread)) { - retval = PTR_ERR(w1_control_thread); - printk(KERN_ERR "Failed to create control thread. err=%d\n", - retval); - goto err_out_slave_unregister; - } - return 0; +#if 0 +/* For undoing the slave register if there was a step after it. */ err_out_slave_unregister: driver_unregister(&w1_slave_driver); +#endif err_out_master_unregister: driver_unregister(&w1_master_driver); @@ -959,13 +1039,12 @@ static void w1_fini(void) { struct w1_master *dev; + /* Set netlink removal messages and some cleanup */ list_for_each_entry(dev, &w1_masters, w1_master_entry) __w1_remove_master_device(dev); w1_fini_netlink(); - kthread_stop(w1_control_thread); - driver_unregister(&w1_slave_driver); driver_unregister(&w1_master_driver); bus_unregister(&w1_bus_type); |