From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pantelis Antoniou Subject: [PATCH v8 4/8] OF: platform: Add OF notifier handler Date: Tue, 28 Oct 2014 22:36:01 +0200 Message-ID: <1414528565-10907-5-git-send-email-pantelis.antoniou@konsulko.com> References: <1414528565-10907-1-git-send-email-pantelis.antoniou@konsulko.com> Cc: Rob Herring , Stephen Warren , Matt Porter , Koen Kooi , Greg Kroah-Hartman , Alison Chaiken , Dinh Nguyen , Jan Lubbe , Alexander Sverdlin , Michael Stickel , Guenter Roeck , Dirk Behme , Alan Tull , Sascha Hauer , Michael Bohan , Ionut Nicu , Michal Simek , Matt Ranostay , Joel Becker , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Wolfram Sang , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Mark Brown , linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, To: Grant Likely Return-path: In-Reply-To: <1414528565-10907-1-git-send-email-pantelis.antoniou-OWPKS81ov/FWk0Htik3J/w@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-spi.vger.kernel.org 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 --- drivers/base/platform.c | 18 +++++++++-- drivers/of/platform.c | 78 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_platform.h | 10 ++++++ 3 files changed, 103 insertions(+), 3 deletions(-) diff --git a/drivers/base/platform.c b/drivers/base/platform.c index b2afc29..282bfec 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -1002,10 +1002,22 @@ int __init platform_bus_init(void) error = device_register(&platform_bus); if (error) - return error; - error = bus_register(&platform_bus_type); + goto err_out; + + error = bus_register(&platform_bus_type); + if (error) + goto err_unreg_dev; + + error = of_platform_register_reconfig_notifier(); if (error) - device_unregister(&platform_bus); + goto err_unreg_bus; + + return 0; +err_unreg_bus: + bus_unregister(&platform_bus_type); +err_unreg_dev: + device_unregister(&platform_bus); +err_out: return error; } diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 3b64d0b..aa8db92 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -546,4 +546,82 @@ void of_platform_depopulate(struct device *parent) } EXPORT_SYMBOL_GPL(of_platform_depopulate); +#ifdef CONFIG_OF_DYNAMIC + +static struct notifier_block platform_of_notifier; + +static int of_platform_notify(struct notifier_block *nb, + unsigned long action, void *arg) +{ + struct platform_device *pdev_parent, *pdev; + struct device_node *dn; + int state; + bool children_left; + + state = of_reconfig_get_state_change(action, arg); + + /* no change? */ + if (state == -1) + return NOTIFY_OK; + + switch (action) { + case OF_RECONFIG_ATTACH_NODE: + case OF_RECONFIG_DETACH_NODE: + dn = arg; + break; + case OF_RECONFIG_ADD_PROPERTY: + case OF_RECONFIG_REMOVE_PROPERTY: + case OF_RECONFIG_UPDATE_PROPERTY: + dn = ((struct of_prop_reconfig *)arg)->dn; + break; + default: + return NOTIFY_OK; + } + + if (state) { + + /* verify that the parent is a bus */ + if (!of_match_node(of_default_bus_match_table, dn->parent)) + return NOTIFY_OK; /* not for us */ + + /* pdev_parent may be NULL when no bus platform device */ + pdev_parent = of_find_device_by_node(dn->parent); + pdev = of_platform_device_create(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__, dn->full_name); + /* of_platform_device_create tosses the error code */ + return notifier_from_errno(-EINVAL); + } + + } else { + + /* find our device by node */ + pdev = of_find_device_by_node(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); + + } + + return NOTIFY_OK; +} + +int of_platform_register_reconfig_notifier(void) +{ + platform_of_notifier.notifier_call = of_platform_notify; + return of_reconfig_notifier_register(&platform_of_notifier); +} +EXPORT_SYMBOL_GPL(of_platform_register_reconfig_notifier); + +#endif + #endif /* CONFIG_OF_ADDRESS */ diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index c2b0627..01fe5d6 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -84,4 +84,14 @@ 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 int of_platform_register_reconfig_notifier(void); +#else +static inline int of_platform_register_reconfig_notifier(void) +{ + return 0; +} +#endif + + #endif /* _LINUX_OF_PLATFORM_H */ -- 1.7.12