From e0bc89c5e7542c36e90d74070ca6af79ff3ec0cf Mon Sep 17 00:00:00 2001 From: Pawel Moll Date: Thu, 15 May 2014 16:55:24 +0100 Subject: [PATCH 1/9] of: Keep track of populated platform devices In "Device Tree powered" systems, platform devices are usually massively populated with of_platform_populate() call, executed at some level of initcalls, either by generic architecture or by platform-specific code. There are situations though where certain devices must be created (and bound with drivers) before all the others. This presents a challenge, as devices created explicitly would be created again by of_platform_populate(). This patch tries to solve that issue in a generic way, adding a "populated" flag for a DT node description. Subsequent of_platform_populate() will skip such nodes (and its children) in a similar way to the non-available ones. This patch also adds of_platform_depopulate() as an operation complementary to the _populate() one. It removes a platform or an amba device populated from the Device Tree, together with its all children (leaving, however, devices without associated of_node untouched) clearing the "populated" flag on the way. Signed-off-by: Pawel Moll Reviewed-by: Rob Herring Acked-by: Grant Likely (cherry picked from commit c6e126de43e7d4abfd6cf796b40589db3a046167) Signed-off-by: Mark Brown Conflicts: drivers/of/platform.c include/linux/of_platform.h --- drivers/of/platform.c | 79 ++++++++++++++++++++++++++++++++++--- include/linux/of.h | 7 ++++ include/linux/of_platform.h | 7 +++- 3 files changed, 86 insertions(+), 7 deletions(-) diff --git a/drivers/of/platform.c b/drivers/of/platform.c index e0a6514ab46c..e6790184a5d2 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 */ @@ -473,4 +484,60 @@ 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 1596e3352326..9755b7a470aa 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -134,6 +134,12 @@ 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); @@ -199,6 +205,7 @@ 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 2a93b64a3869..d7ecf5346278 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -95,6 +95,7 @@ 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); #endif /* CONFIG_OF_ADDRESS */ #endif /* CONFIG_OF_DEVICE */ @@ -109,6 +110,10 @@ static inline int of_platform_populate(struct device_node *root, { return -ENODEV; } -#endif /* !CONFIG_OF_ADDRESS */ +static inline int of_platform_depopulate(struct device *parent) +{ + return -ENODEV; +} +#endif #endif /* _LINUX_OF_PLATFORM_H */ From f2d2cdb9c3bfe92ac575a540b4b3b04313485caa Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Tue, 24 Jun 2014 16:13:47 +0100 Subject: [PATCH 2/9] of/platform: Fix of_platform_device_destroy iteration of devices of_platform_destroy does not work properly, since the tree population test was iterating on all devices having as its parent the given platform device. The check was intended to check whether any other platform or amba devices created by of_platform_populate were still populated, but instead checked for every kind of device. This is wrong, since platform devices typically create a subsystem regular device and set themselves as parents. Instead, go ahead and call the unregister functions for any devices created with of_platform_populate. The driver core will take care of unbinding drivers, and drivers are responsible for getting rid of any child devices that weren't created by of_platform_populate. Signed-off-by: Grant Likely Signed-off-by: Pantelis Antoniou (cherry picked from commit 75f353b61342b5847c7f6d8499fd6301dce09845) Signed-off-by: Mark Brown Conflicts: include/linux/of_platform.h --- drivers/of/platform.c | 32 +++++++++----------------------- include/linux/of.h | 1 + include/linux/of_platform.h | 7 ++----- 3 files changed, 12 insertions(+), 28 deletions(-) diff --git a/drivers/of/platform.c b/drivers/of/platform.c index e6790184a5d2..eb6e20597e82 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -401,6 +401,7 @@ static int of_platform_bus_create(struct device_node *bus, break; } } + of_node_set_flag(bus, OF_POPULATED_BUS); return rc; } @@ -487,19 +488,13 @@ 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; + if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) 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; - } + /* 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)); @@ -507,19 +502,15 @@ static int of_platform_device_destroy(struct device *dev, void *data) 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); - + of_node_clear_flag(dev->of_node, OF_POPULATED_BUS); return 0; } /** * of_platform_depopulate() - Remove devices populated from device tree - * @parent: device which childred will be removed + * @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 @@ -529,14 +520,9 @@ static int of_platform_device_destroy(struct device *dev, void *data) * Returns 0 when all children devices have been removed or * -EBUSY when some children remained. */ -int of_platform_depopulate(struct device *parent) +void 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; + device_for_each_child(parent, NULL, of_platform_device_destroy); } EXPORT_SYMBOL_GPL(of_platform_depopulate); diff --git a/include/linux/of.h b/include/linux/of.h index 9755b7a470aa..f270a2041f29 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -206,6 +206,7 @@ static inline unsigned long of_read_ulong(const __be32 *cell, int size) #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_POPULATED_BUS 4 /* of_platform_populate recursed to children of this 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 d7ecf5346278..3e989ed04e3f 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -95,7 +95,7 @@ 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); +extern void of_platform_depopulate(struct device *parent); #endif /* CONFIG_OF_ADDRESS */ #endif /* CONFIG_OF_DEVICE */ @@ -110,10 +110,7 @@ static inline int of_platform_populate(struct device_node *root, { return -ENODEV; } -static inline int of_platform_depopulate(struct device *parent) -{ - return -ENODEV; -} +static inline void of_platform_depopulate(struct device *parent) { } #endif #endif /* _LINUX_OF_PLATFORM_H */ From b529a532ec6f76517a5e6631c37e8951a079a24b Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Tue, 28 Oct 2014 22:36:01 +0200 Subject: [PATCH 3/9] of/reconfig: Add OF_DYNAMIC notifier for platform_bus_type Add OF notifier handler needed for creating/destroying platform devices according to dynamic runtime changes in the DT live tree. Signed-off-by: Pantelis Antoniou Signed-off-by: Grant Likely (cherry picked from commit 801d728c10db4b28e01590b46bf1f0df930760cc) Signed-off-by: Mark Brown --- drivers/base/platform.c | 1 + drivers/of/platform.c | 55 +++++++++++++++++++++++++++++++++++++ include/linux/of_platform.h | 6 ++++ 3 files changed, 62 insertions(+) diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 9eda84246ffd..2fb6e9888f36 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -913,6 +913,7 @@ int __init platform_bus_init(void) error = bus_register(&platform_bus_type); if (error) device_unregister(&platform_bus); + of_platform_register_reconfig_notifier(); return error; } diff --git a/drivers/of/platform.c b/drivers/of/platform.c index eb6e20597e82..6523eb5bb4eb 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -526,4 +526,59 @@ void of_platform_depopulate(struct device *parent) } 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 */ + + /* 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: + /* 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 */ diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index 3e989ed04e3f..30ebd762063a 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -113,4 +113,10 @@ static inline int of_platform_populate(struct device_node *root, static inline void of_platform_depopulate(struct device *parent) { } #endif +#ifdef CONFIG_OF_DYNAMIC +extern void of_platform_register_reconfig_notifier(void); +#else +static inline void of_platform_register_reconfig_notifier(void) { } +#endif + #endif /* _LINUX_OF_PLATFORM_H */ From 644d38f5abcee9cd78719ede58ef72e1b2ab47e8 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Fri, 14 Nov 2014 15:33:07 +0000 Subject: [PATCH 4/9] of: Use vargs in __of_node_alloc The overlay code needs to construct a new full_name from the parent name and the node name, but the current method has to allocate and then free an temporary string which is wasteful. Fix this problem by using vargs to pass in a format and arguments into __of_node_alloc(). At the same time remove the allocflags argument to __of_node_alloc(). The only users all use GFP_KERNEL, so there is no need to provide it as an option. If there is ever a need later it can be added back. Signed-off-by: Grant Likely (cherry picked from commit ef8bbd73a76197cf8362a2b43aaadc5717bd0746) Signed-off-by: Mark Brown Conflicts: drivers/of/unittest.c --- drivers/of/dynamic.c | 16 ++++++++-------- drivers/of/of_private.h | 2 +- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index bf3e53e243a1..4eaee3ef2fac 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -406,33 +406,33 @@ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags) /** * __of_node_alloc() - Create an empty device node dynamically. * @full_name: Full name of the new device node - * @allocflags: Allocation flags (typically pass GFP_KERNEL) * * Create an empty device tree node, suitable for further modification. * The node data are dynamically allocated and all the node flags * have the OF_DYNAMIC & OF_DETACHED bits set. * Returns the newly allocated node or NULL on out of memory error. */ -struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags) +struct device_node *__of_node_alloc(const char *fmt, ...) { + va_list vargs; struct device_node *node; - node = kzalloc(sizeof(*node), allocflags); + node = kzalloc(sizeof(*node), GFP_KERNEL); if (!node) return NULL; - - node->full_name = kstrdup(full_name, allocflags); - of_node_set_flag(node, OF_DYNAMIC); - of_node_set_flag(node, OF_DETACHED); + va_start(vargs, fmt); + node->full_name = kvasprintf(GFP_KERNEL, fmt, vargs); + va_end(vargs); if (!node->full_name) goto err_free; + of_node_set_flag(node, OF_DYNAMIC); + of_node_set_flag(node, OF_DETACHED); of_node_init(node); return node; err_free: - kfree(node->full_name); kfree(node); return NULL; } diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index 858e0a5d9a11..618abcad307e 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -61,7 +61,7 @@ static inline int of_property_notify(int action, struct device_node *np, * own the devtree lock or work on detached trees only. */ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags); -struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags); +__printf(1, 2) struct device_node *__of_node_alloc(const char *fmt, ...); extern const void *__of_get_property(const struct device_node *np, const char *name, int *lenp); From 1ee737348e46756b420ca9cc1c18afc6e6df9409 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Mon, 17 Nov 2014 22:31:32 +0000 Subject: [PATCH 5/9] of: Refactor __of_node_alloc() into __of_node_dup() Add a node argument to __of_node_alloc() and rename it to __of_node_dup() so that it can also be used to duplicate a node with its properties. This is important for the overlay code so that it can create new nodes without using separate changeset items for every single property. At the same time rework the overlay code to use the new function and drop the extra changeset items. Signed-off-by: Grant Likely (cherry picked from commit e51795815ef1a7adc018cbaf05aac46e3d24eda8) Signed-off-by: Mark Brown Conflicts: drivers/of/unittest.c --- drivers/of/dynamic.c | 40 +++++++++++++++++++++++++++++----------- drivers/of/of_private.h | 2 +- drivers/of/selftest.c | 6 +++--- 3 files changed, 33 insertions(+), 15 deletions(-) diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index 4eaee3ef2fac..16524c8e95ec 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -404,15 +404,16 @@ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags) } /** - * __of_node_alloc() - Create an empty device node dynamically. - * @full_name: Full name of the new device node + * __of_node_dup() - Duplicate or create an empty device node dynamically. + * @fmt: Format string (plus vargs) for new full name of the device node * - * Create an empty device tree node, suitable for further modification. - * The node data are dynamically allocated and all the node flags - * have the OF_DYNAMIC & OF_DETACHED bits set. - * Returns the newly allocated node or NULL on out of memory error. + * Create an device tree node, either by duplicating an empty node or by allocating + * an empty one suitable for further modification. The node data are + * dynamically allocated and all the node flags have the OF_DYNAMIC & + * OF_DETACHED bits set. Returns the newly allocated node or NULL on out of + * memory error. */ -struct device_node *__of_node_alloc(const char *fmt, ...) +struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...) { va_list vargs; struct device_node *node; @@ -423,17 +424,34 @@ struct device_node *__of_node_alloc(const char *fmt, ...) va_start(vargs, fmt); node->full_name = kvasprintf(GFP_KERNEL, fmt, vargs); va_end(vargs); - if (!node->full_name) - goto err_free; + if (!node->full_name) { + kfree(node); + return NULL; + } of_node_set_flag(node, OF_DYNAMIC); of_node_set_flag(node, OF_DETACHED); of_node_init(node); + /* Iterate over and duplicate all properties */ + if (np) { + struct property *pp, *new_pp; + for_each_property_of_node(np, pp) { + new_pp = __of_prop_dup(pp, GFP_KERNEL); + if (!new_pp) + goto err_prop; + if (__of_add_property(node, new_pp)) { + kfree(new_pp->name); + kfree(new_pp->value); + kfree(new_pp); + goto err_prop; + } + } + } return node; - err_free: - kfree(node); + err_prop: + of_node_put(node); /* Frees the node and properties */ return NULL; } diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index 618abcad307e..8e882e706cd8 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -61,7 +61,7 @@ static inline int of_property_notify(int action, struct device_node *np, * own the devtree lock or work on detached trees only. */ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags); -__printf(1, 2) struct device_node *__of_node_alloc(const char *fmt, ...); +__printf(2, 3) struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...); extern const void *__of_get_property(const struct device_node *np, const char *name, int *lenp); diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c index 93058d08f70b..04cb9e5a8292 100644 --- a/drivers/of/selftest.c +++ b/drivers/of/selftest.c @@ -195,11 +195,11 @@ static void __init of_selftest_changeset(void) struct of_changeset chgset; of_changeset_init(&chgset); - n1 = __of_node_alloc("/testcase-data/changeset/n1", GFP_KERNEL); + n1 = __of_node_dup(NULL, "/testcase-data/changeset/n1"); selftest(n1, "testcase setup failure\n"); - n2 = __of_node_alloc("/testcase-data/changeset/n2", GFP_KERNEL); + n2 = __of_node_dup(NULL, "/testcase-data/changeset/n2"); selftest(n2, "testcase setup failure\n"); - n21 = __of_node_alloc("/testcase-data/changeset/n2/n21", GFP_KERNEL); + n21 = __of_node_dup(NULL, "%s/%s", "/testcase-data/changeset/n2", "n21"); selftest(n21, "testcase setup failure %p\n", n21); nremove = of_find_node_by_path("/testcase-data/changeset/node-remove"); selftest(nremove, "testcase setup failure\n"); From 0327df42b40c24073ecd7fb2b81e1511f2f1412d Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Tue, 28 Oct 2014 22:35:58 +0200 Subject: [PATCH 6/9] of/overlay: Introduce DT overlay support Overlays are a method to dynamically modify part of the kernel's device tree with dynamically loaded data. Add the core functionality to parse, apply and remove an overlay changeset. The core functionality takes care of managing the overlay data format and performing the add and remove. Drivers are expected to use the overlay functionality to support custom expansion busses commonly found on consumer development boards like the BeagleBone or Raspberry Pi. The overlay code uses CONFIG_OF_DYNAMIC changesets to perform the low level work of modifying the devicetree. Documentation about internal and APIs is provided in Documentation/devicetree/overlay-notes.txt v2: - Switch from __of_node_alloc() to __of_node_dup() - Documentation fixups - Remove 2-pass processing of properties - Remove separate ov_lock; just use the DT mutex. v1: - Drop delete capability using '-' prefix. The '-' prefixed names are valid properties and nodes and there is no need for it just yet. - Do not update special properties - name & phandle ones. - Change order of node attachment, so that the special property update works. Signed-off-by: Pantelis Antoniou Signed-off-by: Grant Likely (cherry picked from commit 7518b5890d8ac366faa2326ce2356ef6392ce63d) Signed-off-by: Mark Brown Conflicts: drivers/of/Makefile --- Documentation/devicetree/overlay-notes.txt | 133 +++++ drivers/of/Kconfig | 7 + drivers/of/Makefile | 1 + drivers/of/overlay.c | 562 +++++++++++++++++++++ include/linux/of.h | 31 ++ 5 files changed, 734 insertions(+) create mode 100644 Documentation/devicetree/overlay-notes.txt create mode 100644 drivers/of/overlay.c diff --git a/Documentation/devicetree/overlay-notes.txt b/Documentation/devicetree/overlay-notes.txt new file mode 100644 index 000000000000..30ae758e3eef --- /dev/null +++ b/Documentation/devicetree/overlay-notes.txt @@ -0,0 +1,133 @@ +Device Tree Overlay Notes +------------------------- + +This document describes the implementation of the in-kernel +device tree overlay functionality residing in drivers/of/overlay.c and is a +companion document to Documentation/devicetree/dt-object-internal.txt[1] & +Documentation/devicetree/dynamic-resolution-notes.txt[2] + +How overlays work +----------------- + +A Device Tree's overlay purpose is to modify the kernel's live tree, and +have the modification affecting the state of the the kernel in a way that +is reflecting the changes. +Since the kernel mainly deals with devices, any new device node that result +in an active device should have it created while if the device node is either +disabled or removed all together, the affected device should be deregistered. + +Lets take an example where we have a foo board with the following base tree +which is taken from [1]. + +---- foo.dts ----------------------------------------------------------------- + /* FOO platform */ + / { + compatible = "corp,foo"; + + /* shared resources */ + res: res { + }; + + /* On chip peripherals */ + ocp: ocp { + /* peripherals that are always instantiated */ + peripheral1 { ... }; + } + }; +---- foo.dts ----------------------------------------------------------------- + +The overlay bar.dts, when loaded (and resolved as described in [2]) should + +---- bar.dts ----------------------------------------------------------------- +/plugin/; /* allow undefined label references and record them */ +/ { + .... /* various properties for loader use; i.e. part id etc. */ + fragment@0 { + target = <&ocp>; + __overlay__ { + /* bar peripheral */ + bar { + compatible = "corp,bar"; + ... /* various properties and child nodes */ + } + }; + }; +}; +---- bar.dts ----------------------------------------------------------------- + +result in foo+bar.dts + +---- foo+bar.dts ------------------------------------------------------------- + /* FOO platform + bar peripheral */ + / { + compatible = "corp,foo"; + + /* shared resources */ + res: res { + }; + + /* On chip peripherals */ + ocp: ocp { + /* peripherals that are always instantiated */ + peripheral1 { ... }; + + /* bar peripheral */ + bar { + compatible = "corp,bar"; + ... /* various properties and child nodes */ + } + } + }; +---- foo+bar.dts ------------------------------------------------------------- + +As a result of the the overlay, a new device node (bar) has been created +so a bar platform device will be registered and if a matching device driver +is loaded the device will be created as expected. + +Overlay in-kernel API +-------------------------------- + +The API is quite easy to use. + +1. Call of_overlay_create() to create and apply an overlay. The return value +is a cookie identifying this overlay. + +2. Call of_overlay_destroy() to remove and cleanup the overlay previously +created via the call to of_overlay_create(). Removal of an overlay that +is stacked by another will not be permitted. + +Finally, if you need to remove all overlays in one-go, just call +of_overlay_destroy_all() which will remove every single one in the correct +order. + +Overlay DTS Format +------------------ + +The DTS of an overlay should have the following format: + +{ + /* ignored properties by the overlay */ + + fragment@0 { /* first child node */ + + target=; /* phandle target of the overlay */ + or + target-path="/path"; /* target path of the overlay */ + + __overlay__ { + property-a; /* add property-a to the target */ + node-a { /* add to an existing, or create a node-a */ + ... + }; + }; + } + fragment@1 { /* second child node */ + ... + }; + /* more fragments follow */ +} + +Using the non-phandle based target method allows one to use a base DT which does +not contain a __symbols__ node, i.e. it was not compiled with the -@ option. +The __symbols__ node is only required for the target= method, since it +contains the information required to map from a phandle to a tree location. diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index 78384870b337..841a16443b59 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -78,4 +78,11 @@ config OF_MTD config OF_RESOLVE bool +config OF_OVERLAY + bool + depends on OF + select OF_DYNAMIC + select OF_DEVICE + select OF_RESOLVE + endmenu # OF diff --git a/drivers/of/Makefile b/drivers/of/Makefile index 3841eb368ccc..14cb50372b3b 100644 --- a/drivers/of/Makefile +++ b/drivers/of/Makefile @@ -13,3 +13,4 @@ obj-$(CONFIG_OF_PCI) += of_pci.o obj-$(CONFIG_OF_PCI_IRQ) += of_pci_irq.o obj-$(CONFIG_OF_MTD) += of_mtd.o obj-$(CONFIG_OF_RESOLVE) += resolver.o +obj-$(CONFIG_OF_OVERLAY) += overlay.o diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c new file mode 100644 index 000000000000..ea63fbd228ed --- /dev/null +++ b/drivers/of/overlay.c @@ -0,0 +1,562 @@ +/* + * Functions for working with device tree overlays + * + * Copyright (C) 2012 Pantelis Antoniou + * Copyright (C) 2012 Texas Instruments Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + */ +#undef DEBUG +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "of_private.h" + +/** + * struct of_overlay_info - Holds a single overlay info + * @target: target of the overlay operation + * @overlay: pointer to the overlay contents node + * + * Holds a single overlay state, including all the overlay logs & + * records. + */ +struct of_overlay_info { + struct device_node *target; + struct device_node *overlay; +}; + +/** + * struct of_overlay - Holds a complete overlay transaction + * @node: List on which we are located + * @count: Count of ovinfo structures + * @ovinfo_tab: Overlay info table (count sized) + * @cset: Changeset to be used + * + * Holds a complete overlay transaction + */ +struct of_overlay { + int id; + struct list_head node; + int count; + struct of_overlay_info *ovinfo_tab; + struct of_changeset cset; +}; + +static int of_overlay_apply_one(struct of_overlay *ov, + struct device_node *target, const struct device_node *overlay); + +static int of_overlay_apply_single_property(struct of_overlay *ov, + struct device_node *target, struct property *prop) +{ + struct property *propn, *tprop; + + /* NOTE: Multiple changes of single properties not supported */ + tprop = of_find_property(target, prop->name, NULL); + + /* special properties are not meant to be updated (silent NOP) */ + if (of_prop_cmp(prop->name, "name") == 0 || + of_prop_cmp(prop->name, "phandle") == 0 || + of_prop_cmp(prop->name, "linux,phandle") == 0) + return 0; + + propn = __of_prop_dup(prop, GFP_KERNEL); + if (propn == NULL) + return -ENOMEM; + + /* not found? add */ + if (tprop == NULL) + return of_changeset_add_property(&ov->cset, target, propn); + + /* found? update */ + return of_changeset_update_property(&ov->cset, target, propn); +} + +static int of_overlay_apply_single_device_node(struct of_overlay *ov, + struct device_node *target, struct device_node *child) +{ + const char *cname; + struct device_node *tchild, *grandchild; + int ret = 0; + + cname = kbasename(child->full_name); + if (cname == NULL) + return -ENOMEM; + + /* NOTE: Multiple mods of created nodes not supported */ + tchild = of_get_child_by_name(target, cname); + if (tchild != NULL) { + /* apply overlay recursively */ + ret = of_overlay_apply_one(ov, tchild, child); + of_node_put(tchild); + } else { + /* create empty tree as a target */ + tchild = __of_node_dup(child, "%s/%s", target->full_name, cname); + if (!tchild) + return -ENOMEM; + + /* point to parent */ + tchild->parent = target; + + ret = of_changeset_attach_node(&ov->cset, tchild); + if (ret) + return ret; + + ret = of_overlay_apply_one(ov, tchild, child); + if (ret) + return ret; + + /* The properties are already copied, now do the child nodes */ + for_each_child_of_node(child, grandchild) { + ret = of_overlay_apply_single_device_node(ov, tchild, grandchild); + if (ret) { + pr_err("%s: Failed to apply single node @%s/%s\n", + __func__, tchild->full_name, + grandchild->name); + return ret; + } + } + } + + return ret; +} + +/* + * Apply a single overlay node recursively. + * + * Note that the in case of an error the target node is left + * in a inconsistent state. Error recovery should be performed + * by using the changeset. + */ +static int of_overlay_apply_one(struct of_overlay *ov, + struct device_node *target, const struct device_node *overlay) +{ + struct device_node *child; + struct property *prop; + int ret; + + for_each_property_of_node(overlay, prop) { + ret = of_overlay_apply_single_property(ov, target, prop); + if (ret) { + pr_err("%s: Failed to apply prop @%s/%s\n", + __func__, target->full_name, prop->name); + return ret; + } + } + + for_each_child_of_node(overlay, child) { + ret = of_overlay_apply_single_device_node(ov, target, child); + if (ret != 0) { + pr_err("%s: Failed to apply single node @%s/%s\n", + __func__, target->full_name, + child->name); + return ret; + } + } + + return 0; +} + +/** + * of_overlay_apply() - Apply @count overlays pointed at by @ovinfo_tab + * @ov: Overlay to apply + * + * Applies the overlays given, while handling all error conditions + * appropriately. Either the operation succeeds, or if it fails the + * live tree is reverted to the state before the attempt. + * Returns 0, or an error if the overlay attempt failed. + */ +static int of_overlay_apply(struct of_overlay *ov) +{ + int i, err; + + /* first we apply the overlays atomically */ + for (i = 0; i < ov->count; i++) { + struct of_overlay_info *ovinfo = &ov->ovinfo_tab[i]; + + err = of_overlay_apply_one(ov, ovinfo->target, ovinfo->overlay); + if (err != 0) { + pr_err("%s: overlay failed '%s'\n", + __func__, ovinfo->target->full_name); + return err; + } + } + + return 0; +} + +/* + * Find the target node using a number of different strategies + * in order of preference + * + * "target" property containing the phandle of the target + * "target-path" property containing the path of the target + */ +static struct device_node *find_target_node(struct device_node *info_node) +{ + const char *path; + u32 val; + int ret; + + /* first try to go by using the target as a phandle */ + ret = of_property_read_u32(info_node, "target", &val); + if (ret == 0) + return of_find_node_by_phandle(val); + + /* now try to locate by path */ + ret = of_property_read_string(info_node, "target-path", &path); + if (ret == 0) + return of_find_node_by_path(path); + + pr_err("%s: Failed to find target for node %p (%s)\n", __func__, + info_node, info_node->name); + + return NULL; +} + +/** + * of_fill_overlay_info() - Fill an overlay info structure + * @ov Overlay to fill + * @info_node: Device node containing the overlay + * @ovinfo: Pointer to the overlay info structure to fill + * + * Fills an overlay info structure with the overlay information + * from a device node. This device node must have a target property + * which contains a phandle of the overlay target node, and an + * __overlay__ child node which has the overlay contents. + * Both ovinfo->target & ovinfo->overlay have their references taken. + * + * Returns 0 on success, or a negative error value. + */ +static int of_fill_overlay_info(struct of_overlay *ov, + struct device_node *info_node, struct of_overlay_info *ovinfo) +{ + ovinfo->overlay = of_get_child_by_name(info_node, "__overlay__"); + if (ovinfo->overlay == NULL) + goto err_fail; + + ovinfo->target = find_target_node(info_node); + if (ovinfo->target == NULL) + goto err_fail; + + return 0; + +err_fail: + of_node_put(ovinfo->target); + of_node_put(ovinfo->overlay); + + memset(ovinfo, 0, sizeof(*ovinfo)); + return -EINVAL; +} + +/** + * of_build_overlay_info() - Build an overlay info array + * @ov Overlay to build + * @tree: Device node containing all the overlays + * + * Helper function that given a tree containing overlay information, + * allocates and builds an overlay info array containing it, ready + * for use using of_overlay_apply. + * + * Returns 0 on success with the @cntp @ovinfop pointers valid, + * while on error a negative error value is returned. + */ +static int of_build_overlay_info(struct of_overlay *ov, + struct device_node *tree) +{ + struct device_node *node; + struct of_overlay_info *ovinfo; + int cnt, err; + + /* worst case; every child is a node */ + cnt = 0; + for_each_child_of_node(tree, node) + cnt++; + + ovinfo = kcalloc(cnt, sizeof(*ovinfo), GFP_KERNEL); + if (ovinfo == NULL) + return -ENOMEM; + + cnt = 0; + for_each_child_of_node(tree, node) { + memset(&ovinfo[cnt], 0, sizeof(*ovinfo)); + err = of_fill_overlay_info(ov, node, &ovinfo[cnt]); + if (err == 0) + cnt++; + } + + /* if nothing filled, return error */ + if (cnt == 0) { + kfree(ovinfo); + return -ENODEV; + } + + ov->count = cnt; + ov->ovinfo_tab = ovinfo; + + return 0; +} + +/** + * of_free_overlay_info() - Free an overlay info array + * @ov Overlay to free the overlay info from + * @ovinfo_tab: Array of overlay_info's to free + * + * Releases the memory of a previously allocated ovinfo array + * by of_build_overlay_info. + * Returns 0, or an error if the arguments are bogus. + */ +static int of_free_overlay_info(struct of_overlay *ov) +{ + struct of_overlay_info *ovinfo; + int i; + + /* do it in reverse */ + for (i = ov->count - 1; i >= 0; i--) { + ovinfo = &ov->ovinfo_tab[i]; + + of_node_put(ovinfo->target); + of_node_put(ovinfo->overlay); + } + kfree(ov->ovinfo_tab); + + return 0; +} + +static LIST_HEAD(ov_list); +static DEFINE_IDR(ov_idr); + +/** + * of_overlay_create() - Create and apply an overlay + * @tree: Device node containing all the overlays + * + * Creates and applies an overlay while also keeping track + * of the overlay in a list. This list can be used to prevent + * illegal overlay removals. + * + * Returns the id of the created overlay, or an negative error number + */ +int of_overlay_create(struct device_node *tree) +{ + struct of_overlay *ov; + int err, id; + + /* allocate the overlay structure */ + ov = kzalloc(sizeof(*ov), GFP_KERNEL); + if (ov == NULL) + return -ENOMEM; + ov->id = -1; + + INIT_LIST_HEAD(&ov->node); + + of_changeset_init(&ov->cset); + + mutex_lock(&of_mutex); + + id = idr_alloc(&ov_idr, ov, 0, 0, GFP_KERNEL); + if (id < 0) { + pr_err("%s: idr_alloc() failed for tree@%s\n", + __func__, tree->full_name); + err = id; + goto err_destroy_trans; + } + ov->id = id; + + /* build the overlay info structures */ + err = of_build_overlay_info(ov, tree); + if (err) { + pr_err("%s: of_build_overlay_info() failed for tree@%s\n", + __func__, tree->full_name); + goto err_free_idr; + } + + /* apply the overlay */ + err = of_overlay_apply(ov); + if (err) { + pr_err("%s: of_overlay_apply() failed for tree@%s\n", + __func__, tree->full_name); + goto err_abort_trans; + } + + /* apply the changeset */ + err = of_changeset_apply(&ov->cset); + if (err) { + pr_err("%s: of_changeset_apply() failed for tree@%s\n", + __func__, tree->full_name); + goto err_revert_overlay; + } + + /* add to the tail of the overlay list */ + list_add_tail(&ov->node, &ov_list); + + mutex_unlock(&of_mutex); + + return id; + +err_revert_overlay: +err_abort_trans: + of_free_overlay_info(ov); +err_free_idr: + idr_remove(&ov_idr, ov->id); +err_destroy_trans: + of_changeset_destroy(&ov->cset); + kfree(ov); + mutex_unlock(&of_mutex); + + return err; +} +EXPORT_SYMBOL_GPL(of_overlay_create); + +/* check whether the given node, lies under the given tree */ +static int overlay_subtree_check(struct device_node *tree, + struct device_node *dn) +{ + struct device_node *child; + + /* match? */ + if (tree == dn) + return 1; + + for_each_child_of_node(tree, child) { + if (overlay_subtree_check(child, dn)) + return 1; + } + + return 0; +} + +/* check whether this overlay is the topmost */ +static int overlay_is_topmost(struct of_overlay *ov, struct device_node *dn) +{ + struct of_overlay *ovt; + struct of_changeset_entry *ce; + + list_for_each_entry_reverse(ovt, &ov_list, node) { + /* if we hit ourselves, we're done */ + if (ovt == ov) + break; + + /* check against each subtree affected by this overlay */ + list_for_each_entry(ce, &ovt->cset.entries, node) { + if (overlay_subtree_check(ce->np, dn)) { + pr_err("%s: #%d clashes #%d @%s\n", + __func__, ov->id, ovt->id, + dn->full_name); + return 0; + } + } + } + + /* overlay is topmost */ + return 1; +} + +/* + * We can safely remove the overlay only if it's the top-most one. + * Newly applied overlays are inserted at the tail of the overlay list, + * so a top most overlay is the one that is closest to the tail. + * + * The topmost check is done by exploiting this property. For each + * affected device node in the log list we check if this overlay is + * the one closest to the tail. If another overlay has affected this + * device node and is closest to the tail, then removal is not permited. + */ +static int overlay_removal_is_ok(struct of_overlay *ov) +{ + struct of_changeset_entry *ce; + + list_for_each_entry(ce, &ov->cset.entries, node) { + if (!overlay_is_topmost(ov, ce->np)) { + pr_err("%s: overlay #%d is not topmost\n", + __func__, ov->id); + return 0; + } + } + + return 1; +} + +/** + * of_overlay_destroy() - Removes an overlay + * @id: Overlay id number returned by a previous call to of_overlay_create + * + * Removes an overlay if it is permissible. + * + * Returns 0 on success, or an negative error number + */ +int of_overlay_destroy(int id) +{ + struct of_overlay *ov; + int err; + + mutex_lock(&of_mutex); + + ov = idr_find(&ov_idr, id); + if (ov == NULL) { + err = -ENODEV; + pr_err("%s: Could not find overlay #%d\n", + __func__, id); + goto out; + } + + /* check whether the overlay is safe to remove */ + if (!overlay_removal_is_ok(ov)) { + err = -EBUSY; + pr_err("%s: removal check failed for overlay #%d\n", + __func__, id); + goto out; + } + + + list_del(&ov->node); + of_changeset_revert(&ov->cset); + of_free_overlay_info(ov); + idr_remove(&ov_idr, id); + of_changeset_destroy(&ov->cset); + kfree(ov); + + err = 0; + +out: + mutex_unlock(&of_mutex); + + return err; +} +EXPORT_SYMBOL_GPL(of_overlay_destroy); + +/** + * of_overlay_destroy_all() - Removes all overlays from the system + * + * Removes all overlays from the system in the correct order. + * + * Returns 0 on success, or an negative error number + */ +int of_overlay_destroy_all(void) +{ + struct of_overlay *ov, *ovn; + + mutex_lock(&of_mutex); + + /* the tail of list is guaranteed to be safe to remove */ + list_for_each_entry_safe_reverse(ov, ovn, &ov_list, node) { + list_del(&ov->node); + of_changeset_revert(&ov->cset); + of_free_overlay_info(ov); + idr_remove(&ov_idr, ov->id); + kfree(ov); + } + + mutex_unlock(&of_mutex); + + return 0; +} +EXPORT_SYMBOL_GPL(of_overlay_destroy_all); diff --git a/include/linux/of.h b/include/linux/of.h index f270a2041f29..b1fdbfd03546 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -23,6 +23,7 @@ #include #include #include +#include #include #include @@ -808,4 +809,34 @@ static inline int of_reconfig_get_state_change(unsigned long action, /* CONFIG_OF_RESOLVE api */ extern int of_resolve_phandles(struct device_node *tree); +/** + * Overlay support + */ + +#ifdef CONFIG_OF_OVERLAY + +/* ID based overlays; the API for external users */ +int of_overlay_create(struct device_node *tree); +int of_overlay_destroy(int id); +int of_overlay_destroy_all(void); + +#else + +static inline int of_overlay_create(struct device_node *tree) +{ + return -ENOTSUPP; +} + +static inline int of_overlay_destroy(int id) +{ + return -ENOTSUPP; +} + +static inline int of_overlay_destroy_all(void) +{ + return -ENOTSUPP; +} + +#endif + #endif /* _LINUX_OF_H */ From 5e3b95753e328dc2468e2865cbe6ec93a87594ca Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Tue, 16 Dec 2014 19:45:25 +0200 Subject: [PATCH 7/9] of/overlay: Do not generate duplicate nodes During the course of the rewrites a bug sneaked in when dealing with children nodes of overlays, which ends up duplicating sub nodes. Simply remove the duplicate traversal of child nodes to fix. Signed-off-by: Pantelis Antoniou Signed-off-by: Grant Likely (cherry picked from commit 3e7f7626fd49a9ffba8520a1a073f62929acad63) Signed-off-by: Mark Brown --- drivers/of/overlay.c | 11 ----------- 1 file changed, 11 deletions(-) diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index ea63fbd228ed..352b4f28f82c 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -114,17 +114,6 @@ static int of_overlay_apply_single_device_node(struct of_overlay *ov, ret = of_overlay_apply_one(ov, tchild, child); if (ret) return ret; - - /* The properties are already copied, now do the child nodes */ - for_each_child_of_node(child, grandchild) { - ret = of_overlay_apply_single_device_node(ov, tchild, grandchild); - if (ret) { - pr_err("%s: Failed to apply single node @%s/%s\n", - __func__, tchild->full_name, - grandchild->name); - return ret; - } - } } return ret; From 3472bee304a345ccc66b5e09d469abe5acc20d0e Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Tue, 16 Dec 2014 19:45:26 +0200 Subject: [PATCH 8/9] of/platform: Handle of_populate drivers in notifier When using overlays with drivers calling of_populate the notifier will try to create the device twice. Using the populated bit before proceeding protects against this. Signed-off-by: Pantelis Antoniou Signed-off-by: Grant Likely (cherry picked from commit 15204ab1ebc5aba608cd19c83c37b98438b938b0) Signed-off-by: Mark Brown --- drivers/of/platform.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 6523eb5bb4eb..41bff21a0829 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -540,6 +540,10 @@ static int of_platform_notify(struct notifier_block *nb, 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, @@ -555,6 +559,11 @@ static int of_platform_notify(struct notifier_block *nb, 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) From 82b67d73b121febe5ae76747680a2d979c21c5e6 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 17 Feb 2015 11:35:02 +0900 Subject: [PATCH 9/9] of/overlay: Directly include idr.h The overlay code uses IDRs but does not explicitly include the header providing the interface, instead relying on an implicit inclusion. Make the dependency implict to avoid potential future build issues if the implicit inclusion goes away. Signed-off-by: Mark Brown --- drivers/of/overlay.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index 352b4f28f82c..406664801cb5 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "of_private.h"