diff options
| -rw-r--r-- | drivers/of/platform.c | 74 | ||||
| -rw-r--r-- | include/linux/of.h | 7 | ||||
| -rw-r--r-- | include/linux/of_platform.h | 5 |
3 files changed, 81 insertions, 5 deletions
diff --git a/drivers/of/platform.c b/drivers/of/platform.c index bd47fbc53dc9..e8376d646d98 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -206,12 +206,13 @@ static 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; @@ -229,10 +230,14 @@ static 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; } /** @@ -264,14 +269,15 @@ 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) { pr_err("%s(): amba_device_alloc() failed for %s\n", __func__, node->full_name); - return NULL; + goto err_clear_flag; } /* setup generic device info */ @@ -311,6 +317,8 @@ 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 */ @@ -487,4 +495,60 @@ 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) +{ + bool *children_left = data; + + /* Do not touch devices not populated from the device tree */ + if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) { + *children_left = true; + return 0; + } + + /* Recurse, but don't touch this device if it has any children left */ + if (of_platform_depopulate(dev) != 0) { + *children_left = true; + return 0; + } + + 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 + else { + *children_left = true; + return 0; + } + + of_node_clear_flag(dev->of_node, OF_POPULATED); + + return 0; +} + +/** + * of_platform_depopulate() - Remove devices populated from device tree + * @parent: device which childred 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. + */ +int of_platform_depopulate(struct device *parent) +{ + bool children_left = false; + + device_for_each_child(parent, &children_left, + of_platform_device_destroy); + + return children_left ? -EBUSY : 0; +} +EXPORT_SYMBOL_GPL(of_platform_depopulate); + #endif /* CONFIG_OF_ADDRESS */ diff --git a/include/linux/of.h b/include/linux/of.h index 3bad8d106e0e..4c50d0b78b89 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -130,6 +130,12 @@ static inline int of_node_check_flag(struct device_node *n, unsigned long flag) return test_bit(flag, &n->_flags); } +static inline int of_node_test_and_set_flag(struct device_node *n, + unsigned long flag) +{ + return test_and_set_bit(flag, &n->_flags); +} + static inline void of_node_set_flag(struct device_node *n, unsigned long flag) { set_bit(flag, &n->_flags); @@ -197,6 +203,7 @@ static inline unsigned long of_read_ulong(const __be32 *cell, int size) /* flag descriptions */ #define OF_DYNAMIC 1 /* node and properties were allocated via kmalloc */ #define OF_DETACHED 2 /* node has been detached from the device tree */ +#define OF_POPULATED 3 /* device already created for the node */ #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags) #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags) diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index 05cb4a928252..b1010eeaac0d 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -72,6 +72,7 @@ extern int of_platform_populate(struct device_node *root, const struct of_device_id *matches, const struct of_dev_auxdata *lookup, struct device *parent); +extern int of_platform_depopulate(struct device *parent); #else static inline int of_platform_populate(struct device_node *root, const struct of_device_id *matches, @@ -80,6 +81,10 @@ static inline int of_platform_populate(struct device_node *root, { return -ENODEV; } +static inline int of_platform_depopulate(struct device *parent) +{ + return -ENODEV; +} #endif #endif /* _LINUX_OF_PLATFORM_H */ |