Merge tag 'v5.9-rc2' into regulator-5.9

Linux 5.9-rc2

1 files changed, 333 insertions, 37 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 67d39a90b45c..ac1046a382bc 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -50,6 +50,7 @@ static DEFINE_MUTEX(wfs_lock);
 static LIST_HEAD(deferred_sync);
 static unsigned int defer_sync_state_count = 1;
 static unsigned int defer_fw_devlink_count;
+static LIST_HEAD(deferred_fw_devlink);
 static DEFINE_MUTEX(defer_fw_devlink_lock);
 static bool fw_devlink_is_permissive(void);
 
@@ -121,7 +122,7 @@ int device_links_read_lock_held(void)
  * Check if @target depends on @dev or any device dependent on it (its child or
  * its consumer etc).  Return 1 if that is the case or 0 otherwise.
  */
-static int device_is_dependent(struct device *dev, void *target)
+int device_is_dependent(struct device *dev, void *target)
 {
 	struct device_link *link;
 	int ret;
@@ -235,6 +236,210 @@ void device_pm_move_to_tail(struct device *dev)
 	device_links_read_unlock(idx);
 }
 
+#define to_devlink(dev)	container_of((dev), struct device_link, link_dev)
+
+static ssize_t status_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	char *status;
+
+	switch (to_devlink(dev)->status) {
+	case DL_STATE_NONE:
+		status = "not tracked"; break;
+	case DL_STATE_DORMANT:
+		status = "dormant"; break;
+	case DL_STATE_AVAILABLE:
+		status = "available"; break;
+	case DL_STATE_CONSUMER_PROBE:
+		status = "consumer probing"; break;
+	case DL_STATE_ACTIVE:
+		status = "active"; break;
+	case DL_STATE_SUPPLIER_UNBIND:
+		status = "supplier unbinding"; break;
+	default:
+		status = "unknown"; break;
+	}
+	return sprintf(buf, "%s\n", status);
+}
+static DEVICE_ATTR_RO(status);
+
+static ssize_t auto_remove_on_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct device_link *link = to_devlink(dev);
+	char *str;
+
+	if (link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER)
+		str = "supplier unbind";
+	else if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER)
+		str = "consumer unbind";
+	else
+		str = "never";
+
+	return sprintf(buf, "%s\n", str);
+}
+static DEVICE_ATTR_RO(auto_remove_on);
+
+static ssize_t runtime_pm_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct device_link *link = to_devlink(dev);
+
+	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME));
+}
+static DEVICE_ATTR_RO(runtime_pm);
+
+static ssize_t sync_state_only_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct device_link *link = to_devlink(dev);
+
+	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_SYNC_STATE_ONLY));
+}
+static DEVICE_ATTR_RO(sync_state_only);
+
+static struct attribute *devlink_attrs[] = {
+	&dev_attr_status.attr,
+	&dev_attr_auto_remove_on.attr,
+	&dev_attr_runtime_pm.attr,
+	&dev_attr_sync_state_only.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(devlink);
+
+static void device_link_free(struct device_link *link)
+{
+	while (refcount_dec_not_one(&link->rpm_active))
+		pm_runtime_put(link->supplier);
+
+	put_device(link->consumer);
+	put_device(link->supplier);
+	kfree(link);
+}
+
+#ifdef CONFIG_SRCU
+static void __device_link_free_srcu(struct rcu_head *rhead)
+{
+	device_link_free(container_of(rhead, struct device_link, rcu_head));
+}
+
+static void devlink_dev_release(struct device *dev)
+{
+	struct device_link *link = to_devlink(dev);
+
+	call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu);
+}
+#else
+static void devlink_dev_release(struct device *dev)
+{
+	device_link_free(to_devlink(dev));
+}
+#endif
+
+static struct class devlink_class = {
+	.name = "devlink",
+	.owner = THIS_MODULE,
+	.dev_groups = devlink_groups,
+	.dev_release = devlink_dev_release,
+};
+
+static int devlink_add_symlinks(struct device *dev,
+				struct class_interface *class_intf)
+{
+	int ret;
+	size_t len;
+	struct device_link *link = to_devlink(dev);
+	struct device *sup = link->supplier;
+	struct device *con = link->consumer;
+	char *buf;
+
+	len = max(strlen(dev_name(sup)), strlen(dev_name(con)));
+	len += strlen("supplier:") + 1;
+	buf = kzalloc(len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = sysfs_create_link(&link->link_dev.kobj, &sup->kobj, "supplier");
+	if (ret)
+		goto out;
+
+	ret = sysfs_create_link(&link->link_dev.kobj, &con->kobj, "consumer");
+	if (ret)
+		goto err_con;
+
+	snprintf(buf, len, "consumer:%s", dev_name(con));
+	ret = sysfs_create_link(&sup->kobj, &link->link_dev.kobj, buf);
+	if (ret)
+		goto err_con_dev;
+
+	snprintf(buf, len, "supplier:%s", dev_name(sup));
+	ret = sysfs_create_link(&con->kobj, &link->link_dev.kobj, buf);
+	if (ret)
+		goto err_sup_dev;
+
+	goto out;
+
+err_sup_dev:
+	snprintf(buf, len, "consumer:%s", dev_name(con));
+	sysfs_remove_link(&sup->kobj, buf);
+err_con_dev:
+	sysfs_remove_link(&link->link_dev.kobj, "consumer");
+err_con:
+	sysfs_remove_link(&link->link_dev.kobj, "supplier");
+out:
+	kfree(buf);
+	return ret;
+}
+
+static void devlink_remove_symlinks(struct device *dev,
+				   struct class_interface *class_intf)
+{
+	struct device_link *link = to_devlink(dev);
+	size_t len;
+	struct device *sup = link->supplier;
+	struct device *con = link->consumer;
+	char *buf;
+
+	sysfs_remove_link(&link->link_dev.kobj, "consumer");
+	sysfs_remove_link(&link->link_dev.kobj, "supplier");
+
+	len = max(strlen(dev_name(sup)), strlen(dev_name(con)));
+	len += strlen("supplier:") + 1;
+	buf = kzalloc(len, GFP_KERNEL);
+	if (!buf) {
+		WARN(1, "Unable to properly free device link symlinks!\n");
+		return;
+	}
+
+	snprintf(buf, len, "supplier:%s", dev_name(sup));
+	sysfs_remove_link(&con->kobj, buf);
+	snprintf(buf, len, "consumer:%s", dev_name(con));
+	sysfs_remove_link(&sup->kobj, buf);
+	kfree(buf);
+}
+
+static struct class_interface devlink_class_intf = {
+	.class = &devlink_class,
+	.add_dev = devlink_add_symlinks,
+	.remove_dev = devlink_remove_symlinks,
+};
+
+static int __init devlink_class_init(void)
+{
+	int ret;
+
+	ret = class_register(&devlink_class);
+	if (ret)
+		return ret;
+
+	ret = class_interface_register(&devlink_class_intf);
+	if (ret)
+		class_unregister(&devlink_class);
+
+	return ret;
+}
+postcore_initcall(devlink_class_init);
+
 #define DL_MANAGED_LINK_FLAGS (DL_FLAG_AUTOREMOVE_CONSUMER | \
 			       DL_FLAG_AUTOREMOVE_SUPPLIER | \
 			       DL_FLAG_AUTOPROBE_CONSUMER  | \
@@ -407,13 +612,6 @@ struct device_link *device_link_add(struct device *consumer,
 
 	refcount_set(&link->rpm_active, 1);
 
-	if (flags & DL_FLAG_PM_RUNTIME) {
-		if (flags & DL_FLAG_RPM_ACTIVE)
-			refcount_inc(&link->rpm_active);
-
-		pm_runtime_new_link(consumer);
-	}
-
 	get_device(supplier);
 	link->supplier = supplier;
 	INIT_LIST_HEAD(&link->s_node);
@@ -423,6 +621,25 @@ struct device_link *device_link_add(struct device *consumer,
 	link->flags = flags;
 	kref_init(&link->kref);
 
+	link->link_dev.class = &devlink_class;
+	device_set_pm_not_required(&link->link_dev);
+	dev_set_name(&link->link_dev, "%s--%s",
+		     dev_name(supplier), dev_name(consumer));
+	if (device_register(&link->link_dev)) {
+		put_device(consumer);
+		put_device(supplier);
+		kfree(link);
+		link = NULL;
+		goto out;
+	}
+
+	if (flags & DL_FLAG_PM_RUNTIME) {
+		if (flags & DL_FLAG_RPM_ACTIVE)
+			refcount_inc(&link->rpm_active);
+
+		pm_runtime_new_link(consumer);
+	}
+
 	/* Determine the initial link state. */
 	if (flags & DL_FLAG_STATELESS)
 		link->status = DL_STATE_NONE;
@@ -538,22 +755,7 @@ static void device_link_add_missing_supplier_links(void)
 	mutex_unlock(&wfs_lock);
 }
 
-static void device_link_free(struct device_link *link)
-{
-	while (refcount_dec_not_one(&link->rpm_active))
-		pm_runtime_put(link->supplier);
-
-	put_device(link->consumer);
-	put_device(link->supplier);
-	kfree(link);
-}
-
 #ifdef CONFIG_SRCU
-static void __device_link_free_srcu(struct rcu_head *rhead)
-{
-	device_link_free(container_of(rhead, struct device_link, rcu_head));
-}
-
 static void __device_link_del(struct kref *kref)
 {
 	struct device_link *link = container_of(kref, struct device_link, kref);
@@ -566,7 +768,7 @@ static void __device_link_del(struct kref *kref)
 
 	list_del_rcu(&link->s_node);
 	list_del_rcu(&link->c_node);
-	call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu);
+	device_unregister(&link->link_dev);
 }
 #else /* !CONFIG_SRCU */
 static void __device_link_del(struct kref *kref)
@@ -581,7 +783,7 @@ static void __device_link_del(struct kref *kref)
 
 	list_del(&link->s_node);
 	list_del(&link->c_node);
-	device_link_free(link);
+	device_unregister(&link->link_dev);
 }
 #endif /* !CONFIG_SRCU */
 
@@ -754,11 +956,11 @@ static void __device_links_queue_sync_state(struct device *dev,
 	 */
 	dev->state_synced = true;
 
-	if (WARN_ON(!list_empty(&dev->links.defer_sync)))
+	if (WARN_ON(!list_empty(&dev->links.defer_hook)))
 		return;
 
 	get_device(dev);
-	list_add_tail(&dev->links.defer_sync, list);
+	list_add_tail(&dev->links.defer_hook, list);
 }
 
 /**
@@ -776,8 +978,8 @@ static void device_links_flush_sync_list(struct list_head *list,
 {
 	struct device *dev, *tmp;
 
-	list_for_each_entry_safe(dev, tmp, list, links.defer_sync) {
-		list_del_init(&dev->links.defer_sync);
+	list_for_each_entry_safe(dev, tmp, list, links.defer_hook) {
+		list_del_init(&dev->links.defer_hook);
 
 		if (dev != dont_lock_dev)
 			device_lock(dev);
@@ -815,12 +1017,12 @@ void device_links_supplier_sync_state_resume(void)
 	if (defer_sync_state_count)
 		goto out;
 
-	list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_sync) {
+	list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_hook) {
 		/*
 		 * Delete from deferred_sync list before queuing it to
-		 * sync_list because defer_sync is used for both lists.
+		 * sync_list because defer_hook is used for both lists.
 		 */
-		list_del_init(&dev->links.defer_sync);
+		list_del_init(&dev->links.defer_hook);
 		__device_links_queue_sync_state(dev, &sync_list);
 	}
 out:
@@ -838,8 +1040,8 @@ late_initcall(sync_state_resume_initcall);
 
 static void __device_links_supplier_defer_sync(struct device *sup)
 {
-	if (list_empty(&sup->links.defer_sync) && dev_has_sync_state(sup))
-		list_add_tail(&sup->links.defer_sync, &deferred_sync);
+	if (list_empty(&sup->links.defer_hook) && dev_has_sync_state(sup))
+		list_add_tail(&sup->links.defer_hook, &deferred_sync);
 }
 
 static void device_link_drop_managed(struct device_link *link)
@@ -849,6 +1051,22 @@ static void device_link_drop_managed(struct device_link *link)
 	kref_put(&link->kref, __device_link_del);
 }
 
+static ssize_t waiting_for_supplier_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	bool val;
+
+	device_lock(dev);
+	mutex_lock(&wfs_lock);
+	val = !list_empty(&dev->links.needs_suppliers)
+	      && dev->links.need_for_probe;
+	mutex_unlock(&wfs_lock);
+	device_unlock(dev);
+	return sprintf(buf, "%u\n", val);
+}
+static DEVICE_ATTR_RO(waiting_for_supplier);
+
 /**
  * device_links_driver_bound - Update device links after probing its driver.
  * @dev: Device to update the links for.
@@ -873,6 +1091,7 @@ void device_links_driver_bound(struct device *dev)
 	mutex_lock(&wfs_lock);
 	list_del_init(&dev->links.needs_suppliers);
 	mutex_unlock(&wfs_lock);
+	device_remove_file(dev, &dev_attr_waiting_for_supplier);
 
 	device_links_write_lock();
 
@@ -1052,7 +1271,7 @@ void device_links_driver_cleanup(struct device *dev)
 		WRITE_ONCE(link->status, DL_STATE_DORMANT);
 	}
 
-	list_del_init(&dev->links.defer_sync);
+	list_del_init(&dev->links.defer_hook);
 	__device_links_no_driver(dev);
 
 	device_links_write_unlock();
@@ -1159,6 +1378,9 @@ static void device_links_purge(struct device *dev)
 {
 	struct device_link *link, *ln;
 
+	if (dev->class == &devlink_class)
+		return;
+
 	mutex_lock(&wfs_lock);
 	list_del(&dev->links.needs_suppliers);
 	mutex_unlock(&wfs_lock);
@@ -1244,6 +1466,12 @@ static void fw_devlink_link_device(struct device *dev)
 			fw_ret = -EAGAIN;
 	} else {
 		fw_ret = -ENODEV;
+		/*
+		 * defer_hook is not used to add device to deferred_sync list
+		 * until device is bound. Since deferred fw devlink also blocks
+		 * probing, same list hook can be used for deferred_fw_devlink.
+		 */
+		list_add_tail(&dev->links.defer_hook, &deferred_fw_devlink);
 	}
 
 	if (fw_ret == -ENODEV)
@@ -1312,6 +1540,9 @@ void fw_devlink_pause(void)
  */
 void fw_devlink_resume(void)
 {
+	struct device *dev, *tmp;
+	LIST_HEAD(probe_list);
+
 	mutex_lock(&defer_fw_devlink_lock);
 	if (!defer_fw_devlink_count) {
 		WARN(true, "Unmatched fw_devlink pause/resume!");
@@ -1323,9 +1554,19 @@ void fw_devlink_resume(void)
 		goto out;
 
 	device_link_add_missing_supplier_links();
-	driver_deferred_probe_force_trigger();
+	list_splice_tail_init(&deferred_fw_devlink, &probe_list);
 out:
 	mutex_unlock(&defer_fw_devlink_lock);
+
+	/*
+	 * bus_probe_device() can cause new devices to get added and they'll
+	 * try to grab defer_fw_devlink_lock. So, this needs to be done outside
+	 * the defer_fw_devlink_lock.
+	 */
+	list_for_each_entry_safe(dev, tmp, &probe_list, links.defer_hook) {
+		list_del_init(&dev->links.defer_hook);
+		bus_probe_device(dev);
+	}
 }
 /* Device links support end. */
 
@@ -1949,8 +2190,16 @@ static int device_add_attrs(struct device *dev)
 			goto err_remove_dev_groups;
 	}
 
+	if (fw_devlink_flags && !fw_devlink_is_permissive()) {
+		error = device_create_file(dev, &dev_attr_waiting_for_supplier);
+		if (error)
+			goto err_remove_dev_online;
+	}
+
 	return 0;
 
+ err_remove_dev_online:
+	device_remove_file(dev, &dev_attr_online);
  err_remove_dev_groups:
 	device_remove_groups(dev, dev->groups);
  err_remove_type_groups:
@@ -1968,6 +2217,7 @@ static void device_remove_attrs(struct device *dev)
 	struct class *class = dev->class;
 	const struct device_type *type = dev->type;
 
+	device_remove_file(dev, &dev_attr_waiting_for_supplier);
 	device_remove_file(dev, &dev_attr_online);
 	device_remove_groups(dev, dev->groups);
 
@@ -2172,7 +2422,7 @@ void device_initialize(struct device *dev)
 	INIT_LIST_HEAD(&dev->links.consumers);
 	INIT_LIST_HEAD(&dev->links.suppliers);
 	INIT_LIST_HEAD(&dev->links.needs_suppliers);
-	INIT_LIST_HEAD(&dev->links.defer_sync);
+	INIT_LIST_HEAD(&dev->links.defer_hook);
 	dev->links.status = DL_DEV_NO_DRIVER;
 }
 EXPORT_SYMBOL_GPL(device_initialize);
@@ -3953,6 +4203,52 @@ define_dev_printk_level(_dev_info, KERN_INFO);
 
 #endif
 
+/**
+ * dev_err_probe - probe error check and log helper
+ * @dev: the pointer to the struct device
+ * @err: error value to test
+ * @fmt: printf-style format string
+ * @...: arguments as specified in the format string
+ *
+ * This helper implements common pattern present in probe functions for error
+ * checking: print debug or error message depending if the error value is
+ * -EPROBE_DEFER and propagate error upwards.
+ * In case of -EPROBE_DEFER it sets also defer probe reason, which can be
+ * checked later by reading devices_deferred debugfs attribute.
+ * It replaces code sequence:
+ * 	if (err != -EPROBE_DEFER)
+ * 		dev_err(dev, ...);
+ * 	else
+ * 		dev_dbg(dev, ...);
+ * 	return err;
+ * with
+ * 	return dev_err_probe(dev, err, ...);
+ *
+ * Returns @err.
+ *
+ */
+int dev_err_probe(const struct device *dev, int err, const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start(args, fmt);
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	if (err != -EPROBE_DEFER) {
+		dev_err(dev, "error %d: %pV", err, &vaf);
+	} else {
+		device_set_deferred_probe_reason(dev, &vaf);
+		dev_dbg(dev, "error %d: %pV", err, &vaf);
+	}
+
+	va_end(args);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(dev_err_probe);
+
 static inline bool fwnode_is_primary(struct fwnode_handle *fwnode)
 {
 	return fwnode && !IS_ERR(fwnode->secondary);