1 files changed, 22 insertions, 4 deletions

diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 95ea7e6b1d99..0c2a5a8327bd 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -25,6 +25,7 @@
 #include <linux/sched.h>
 #include <linux/kthread.h>
 #include <linux/freezer.h>
+#include <linux/hwmon.h>
 
 #include <linux/atomic.h>
 
@@ -568,7 +569,7 @@ static struct attribute *w1_master_default_attrs[] = {
 	NULL
 };
 
-static struct attribute_group w1_master_defattr_group = {
+static const struct attribute_group w1_master_defattr_group = {
 	.attrs = w1_master_default_attrs,
 };
 
@@ -649,9 +650,24 @@ static int w1_family_notify(unsigned long action, struct w1_slave *sl)
 				return err;
 			}
 		}
-
+		if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info) {
+			struct device *hwmon
+				= hwmon_device_register_with_info(&sl->dev,
+						"w1_slave_temp", sl,
+						fops->chip_info,
+						NULL);
+			if (IS_ERR(hwmon)) {
+				dev_warn(&sl->dev,
+					 "could not create hwmon device\n");
+			} else {
+				sl->hwmon = hwmon;
+			}
+		}
 		break;
 	case BUS_NOTIFY_DEL_DEVICE:
+		if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info &&
+			    sl->hwmon)
+			hwmon_device_unregister(sl->hwmon);
 		if (fops->remove_slave)
 			sl->family->fops->remove_slave(sl);
 		if (fops->groups)
@@ -728,6 +744,9 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
 	memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
 	atomic_set(&sl->refcnt, 1);
 	atomic_inc(&sl->master->refcnt);
+	dev->slave_count++;
+	dev_info(&dev->dev, "Attaching one wire slave %02x.%012llx crc %02x\n",
+		  rn->family, (unsigned long long)rn->id, rn->crc);
 
 	/* slave modules need to be loaded in a context with unlocked mutex */
 	mutex_unlock(&dev->mutex);
@@ -747,11 +766,11 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
 
 	sl->family = f;
 
-
 	err = __w1_attach_slave_device(sl);
 	if (err < 0) {
 		dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__,
 			 sl->name);
+		dev->slave_count--;
 		w1_family_put(sl->family);
 		atomic_dec(&sl->master->refcnt);
 		kfree(sl);
@@ -759,7 +778,6 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
 	}
 
 	sl->ttl = dev->slave_ttl;
-	dev->slave_count++;
 
 	memcpy(msg.id.id, rn, sizeof(msg.id));
 	msg.type = W1_SLAVE_ADD;