diff options
Diffstat (limited to 'drivers/base/core.c')
-rw-r--r-- | drivers/base/core.c | 110 |
1 files changed, 78 insertions, 32 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c index e65dd803a453..fd034d742447 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -95,6 +95,8 @@ int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup) list_add(&link->s_hook, &sup->consumers); list_add(&link->c_hook, &con->suppliers); + pr_debug("%pfwP Linked as a fwnode consumer to %pfwP\n", + con, sup); out: mutex_unlock(&fwnode_link_lock); @@ -102,6 +104,21 @@ out: } /** + * __fwnode_link_del - Delete a link between two fwnode_handles. + * @link: the fwnode_link to be deleted + * + * The fwnode_link_lock needs to be held when this function is called. + */ +static void __fwnode_link_del(struct fwnode_link *link) +{ + pr_debug("%pfwP Dropping the fwnode link to %pfwP\n", + link->consumer, link->supplier); + list_del(&link->s_hook); + list_del(&link->c_hook); + kfree(link); +} + +/** * fwnode_links_purge_suppliers - Delete all supplier links of fwnode_handle. * @fwnode: fwnode whose supplier links need to be deleted * @@ -112,11 +129,8 @@ static void fwnode_links_purge_suppliers(struct fwnode_handle *fwnode) struct fwnode_link *link, *tmp; mutex_lock(&fwnode_link_lock); - list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) { - list_del(&link->s_hook); - list_del(&link->c_hook); - kfree(link); - } + list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) + __fwnode_link_del(link); mutex_unlock(&fwnode_link_lock); } @@ -131,11 +145,8 @@ static void fwnode_links_purge_consumers(struct fwnode_handle *fwnode) struct fwnode_link *link, *tmp; mutex_lock(&fwnode_link_lock); - list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) { - list_del(&link->s_hook); - list_del(&link->c_hook); - kfree(link); - } + list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) + __fwnode_link_del(link); mutex_unlock(&fwnode_link_lock); } @@ -676,7 +687,8 @@ struct device_link *device_link_add(struct device *consumer, { struct device_link *link; - if (!consumer || !supplier || flags & ~DL_ADD_VALID_FLAGS || + if (!consumer || !supplier || consumer == supplier || + flags & ~DL_ADD_VALID_FLAGS || (flags & DL_FLAG_STATELESS && flags & DL_MANAGED_LINK_FLAGS) || (flags & DL_FLAG_SYNC_STATE_ONLY && (flags & ~DL_FLAG_INFERRED) != DL_FLAG_SYNC_STATE_ONLY) || @@ -809,9 +821,7 @@ struct device_link *device_link_add(struct device *consumer, dev_bus_name(supplier), dev_name(supplier), dev_bus_name(consumer), dev_name(consumer)); if (device_register(&link->link_dev)) { - put_device(consumer); - put_device(supplier); - kfree(link); + put_device(&link->link_dev); link = NULL; goto out; } @@ -975,6 +985,7 @@ int device_links_check_suppliers(struct device *dev) { struct device_link *link; int ret = 0; + struct fwnode_handle *sup_fw; /* * Device waiting for supplier to become available is not allowed to @@ -983,10 +994,11 @@ int device_links_check_suppliers(struct device *dev) mutex_lock(&fwnode_link_lock); if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) && !fw_devlink_is_permissive()) { - dev_dbg(dev, "probe deferral - wait for supplier %pfwP\n", - list_first_entry(&dev->fwnode->suppliers, - struct fwnode_link, - c_hook)->supplier); + sup_fw = list_first_entry(&dev->fwnode->suppliers, + struct fwnode_link, + c_hook)->supplier; + dev_err_probe(dev, -EPROBE_DEFER, "wait for supplier %pfwP\n", + sup_fw); mutex_unlock(&fwnode_link_lock); return -EPROBE_DEFER; } @@ -1001,8 +1013,9 @@ int device_links_check_suppliers(struct device *dev) if (link->status != DL_STATE_AVAILABLE && !(link->flags & DL_FLAG_SYNC_STATE_ONLY)) { device_links_missing_supplier(dev); - dev_dbg(dev, "probe deferral - supplier %s not ready\n", - dev_name(link->supplier)); + dev_err_probe(dev, -EPROBE_DEFER, + "supplier %s not ready\n", + dev_name(link->supplier)); ret = -EPROBE_DEFER; break; } @@ -1722,6 +1735,25 @@ static int fw_devlink_create_devlink(struct device *con, struct device *sup_dev; int ret = 0; + /* + * In some cases, a device P might also be a supplier to its child node + * C. However, this would defer the probe of C until the probe of P + * completes successfully. This is perfectly fine in the device driver + * model. device_add() doesn't guarantee probe completion of the device + * by the time it returns. + * + * However, there are a few drivers that assume C will finish probing + * as soon as it's added and before P finishes probing. So, we provide + * a flag to let fw_devlink know not to delay the probe of C until the + * probe of P completes successfully. + * + * When such a flag is set, we can't create device links where P is the + * supplier of C as that would delay the probe of C. + */ + if (sup_handle->flags & FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD && + fwnode_is_ancestor_of(sup_handle, con->fwnode)) + return -EINVAL; + sup_dev = get_dev_from_fwnode(sup_handle); if (sup_dev) { /* @@ -1772,14 +1804,21 @@ static int fw_devlink_create_devlink(struct device *con, * be broken by applying logic. Check for these types of cycles and * break them so that devices in the cycle probe properly. * - * If the supplier's parent is dependent on the consumer, then - * the consumer-supplier dependency is a false dependency. So, - * treat it as an invalid link. + * If the supplier's parent is dependent on the consumer, then the + * consumer and supplier have a cyclic dependency. Since fw_devlink + * can't tell which of the inferred dependencies are incorrect, don't + * enforce probe ordering between any of the devices in this cyclic + * dependency. Do this by relaxing all the fw_devlink device links in + * this cycle and by treating the fwnode link between the consumer and + * the supplier as an invalid dependency. */ sup_dev = fwnode_get_next_parent_dev(sup_handle); if (sup_dev && device_is_dependent(con, sup_dev)) { - dev_dbg(con, "Not linking to %pfwP - False link\n", - sup_handle); + dev_info(con, "Fixing up cyclic dependency with %pfwP (%s)\n", + sup_handle, dev_name(sup_dev)); + device_links_write_lock(); + fw_devlink_relax_cycle(con, sup_dev); + device_links_write_unlock(); ret = -EINVAL; } else { /* @@ -1858,9 +1897,7 @@ static void __fw_devlink_link_to_consumers(struct device *dev) if (!own_link || ret == -EAGAIN) continue; - list_del(&link->s_hook); - list_del(&link->c_hook); - kfree(link); + __fwnode_link_del(link); } } @@ -1912,9 +1949,7 @@ static void __fw_devlink_link_to_suppliers(struct device *dev, if (!own_link || ret == -EAGAIN) continue; - list_del(&link->s_hook); - list_del(&link->c_hook); - kfree(link); + __fwnode_link_del(link); /* If no device link was created, nothing more to do. */ if (ret) @@ -2838,7 +2873,7 @@ void device_initialize(struct device *dev) spin_lock_init(&dev->devres_lock); INIT_LIST_HEAD(&dev->devres_head); device_pm_init(dev); - set_dev_node(dev, -1); + set_dev_node(dev, NUMA_NO_NODE); #ifdef CONFIG_GENERIC_MSI_IRQ raw_spin_lock_init(&dev->msi_lock); INIT_LIST_HEAD(&dev->msi_list); @@ -4653,6 +4688,11 @@ define_dev_printk_level(_dev_info, KERN_INFO); * * return dev_err_probe(dev, err, ...); * + * Note that it is deemed acceptable to use this function for error + * prints during probe even if the @err is known to never be -EPROBE_DEFER. + * The benefit compared to a normal dev_err() is the standardized format + * of the error code and the fact that the error code is returned. + * * Returns @err. * */ @@ -4798,6 +4838,12 @@ int device_match_acpi_dev(struct device *dev, const void *adev) } EXPORT_SYMBOL(device_match_acpi_dev); +int device_match_acpi_handle(struct device *dev, const void *handle) +{ + return ACPI_HANDLE(dev) == handle; +} +EXPORT_SYMBOL(device_match_acpi_handle); + int device_match_any(struct device *dev, const void *unused) { return 1; |