diff options
Diffstat (limited to 'drivers/of/platform.c')
| -rw-r--r-- | drivers/of/platform.c | 129 |
1 files changed, 123 insertions, 6 deletions
diff --git a/drivers/of/platform.c b/drivers/of/platform.c index e0a6514ab46c..41bff21a0829 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -204,12 +204,13 @@ struct platform_device *of_platform_device_create_pdata( { struct platform_device *dev; - if (!of_device_is_available(np)) + if (!of_device_is_available(np) || + of_node_test_and_set_flag(np, OF_POPULATED)) return NULL; dev = of_device_alloc(np, bus_id, parent); if (!dev) - return NULL; + goto err_clear_flag; #if defined(CONFIG_MICROBLAZE) dev->archdata.dma_mask = 0xffffffffUL; @@ -225,10 +226,14 @@ struct platform_device *of_platform_device_create_pdata( if (of_device_add(dev) != 0) { platform_device_put(dev); - return NULL; + goto err_clear_flag; } return dev; + +err_clear_flag: + of_node_clear_flag(np, OF_POPULATED); + return NULL; } /** @@ -260,12 +265,16 @@ static struct amba_device *of_amba_device_create(struct device_node *node, pr_debug("Creating amba device %s\n", node->full_name); - if (!of_device_is_available(node)) + if (!of_device_is_available(node) || + of_node_test_and_set_flag(node, OF_POPULATED)) return NULL; dev = amba_device_alloc(NULL, 0, 0); - if (!dev) - return NULL; + if (!dev) { + pr_err("%s(): amba_device_alloc() failed for %s\n", + __func__, node->full_name); + goto err_clear_flag; + } /* setup generic device info */ dev->dev.coherent_dma_mask = ~0; @@ -301,6 +310,8 @@ static struct amba_device *of_amba_device_create(struct device_node *node, err_free: amba_device_put(dev); +err_clear_flag: + of_node_clear_flag(node, OF_POPULATED); return NULL; } #else /* CONFIG_ARM_AMBA */ @@ -390,6 +401,7 @@ static int of_platform_bus_create(struct device_node *bus, break; } } + of_node_set_flag(bus, OF_POPULATED_BUS); return rc; } @@ -473,4 +485,109 @@ int of_platform_populate(struct device_node *root, return rc; } EXPORT_SYMBOL_GPL(of_platform_populate); + +static int of_platform_device_destroy(struct device *dev, void *data) +{ + /* Do not touch devices not populated from the device tree */ + if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) + return 0; + + /* Recurse for any nodes that were treated as busses */ + if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS)) + device_for_each_child(dev, NULL, of_platform_device_destroy); + + if (dev->bus == &platform_bus_type) + platform_device_unregister(to_platform_device(dev)); +#ifdef CONFIG_ARM_AMBA + else if (dev->bus == &amba_bustype) + amba_device_unregister(to_amba_device(dev)); +#endif + + of_node_clear_flag(dev->of_node, OF_POPULATED); + of_node_clear_flag(dev->of_node, OF_POPULATED_BUS); + return 0; +} + +/** + * of_platform_depopulate() - Remove devices populated from device tree + * @parent: device which children will be removed + * + * Complementary to of_platform_populate(), this function removes children + * of the given device (and, recurrently, their children) that have been + * created from their respective device tree nodes (and only those, + * leaving others - eg. manually created - unharmed). + * + * Returns 0 when all children devices have been removed or + * -EBUSY when some children remained. + */ +void of_platform_depopulate(struct device *parent) +{ + device_for_each_child(parent, NULL, of_platform_device_destroy); +} +EXPORT_SYMBOL_GPL(of_platform_depopulate); + +#ifdef CONFIG_OF_DYNAMIC +static int of_platform_notify(struct notifier_block *nb, + unsigned long action, void *arg) +{ + struct of_reconfig_data *rd = arg; + struct platform_device *pdev_parent, *pdev; + bool children_left; + + switch (of_reconfig_get_state_change(action, rd)) { + case OF_RECONFIG_CHANGE_ADD: + /* verify that the parent is a bus */ + if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS)) + return NOTIFY_OK; /* not for us */ + + /* already populated? (driver using of_populate manually) */ + if (of_node_check_flag(rd->dn, OF_POPULATED)) + return NOTIFY_OK; + + /* pdev_parent may be NULL when no bus platform device */ + pdev_parent = of_find_device_by_node(rd->dn->parent); + pdev = of_platform_device_create(rd->dn, NULL, + pdev_parent ? &pdev_parent->dev : NULL); + of_dev_put(pdev_parent); + + if (pdev == NULL) { + pr_err("%s: failed to create for '%s'\n", + __func__, rd->dn->full_name); + /* of_platform_device_create tosses the error code */ + return notifier_from_errno(-EINVAL); + } + break; + + case OF_RECONFIG_CHANGE_REMOVE: + + /* already depopulated? */ + if (!of_node_check_flag(rd->dn, OF_POPULATED)) + return NOTIFY_OK; + + /* find our device by node */ + pdev = of_find_device_by_node(rd->dn); + if (pdev == NULL) + return NOTIFY_OK; /* no? not meant for us */ + + /* unregister takes one ref away */ + of_platform_device_destroy(&pdev->dev, &children_left); + + /* and put the reference of the find */ + of_dev_put(pdev); + break; + } + + return NOTIFY_OK; +} + +static struct notifier_block platform_of_notifier = { + .notifier_call = of_platform_notify, +}; + +void of_platform_register_reconfig_notifier(void) +{ + WARN_ON(of_reconfig_notifier_register(&platform_of_notifier)); +} +#endif /* CONFIG_OF_DYNAMIC */ + #endif /* CONFIG_OF_ADDRESS */ |