We already expose of_platform_device_create(), but give the caller no chance to revert its effect. Make sure we also provide the counterpart of_platform_device_destroy().
This requires a small refactoring, since so far the internal destructor is used as iterator to for_each_device(), but we don't want to expose it with the "void *data" parameter. So provide of_platform_device_depopulate() as new iterator, which calls into of_platform_device_destroy().
While at it, drop the unused 'children_left' argument by of_platform_notify(). It is a left-over that somehow was never removed.
Signed-off-by: David Herrmann dh.herrmann@gmail.com --- drivers/of/platform.c | 35 ++++++++++++++++++++++++++--------- include/linux/of_platform.h | 1 + 2 files changed, 27 insertions(+), 9 deletions(-)
diff --git a/drivers/of/platform.c b/drivers/of/platform.c index f39ccd5..f9bb563 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -524,15 +524,18 @@ static int __init of_platform_default_populate_init(void) arch_initcall_sync(of_platform_default_populate_init); #endif
-static int of_platform_device_destroy(struct device *dev, void *data) +/** + * of_platform_device_destroy - unregister an of_device + * @dev: device to unregister + * + * This is the inverse operation of of_platform_device_create(). It unregisters + * the passed device, if registered. + */ +void of_platform_device_destroy(struct device *dev) { /* 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); + return;
if (dev->bus == &platform_bus_type) platform_device_unregister(to_platform_device(dev)); @@ -544,6 +547,20 @@ static int of_platform_device_destroy(struct device *dev, void *data) of_dma_deconfigure(dev); of_node_clear_flag(dev->of_node, OF_POPULATED); of_node_clear_flag(dev->of_node, OF_POPULATED_BUS); +} +EXPORT_SYMBOL(of_platform_device_destroy); + +static int of_platform_device_depopulate(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_depopulate); + + of_platform_device_destroy(dev); return 0; }
@@ -562,7 +579,8 @@ static int of_platform_device_destroy(struct device *dev, void *data) void of_platform_depopulate(struct device *parent) { if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) { - device_for_each_child(parent, NULL, of_platform_device_destroy); + device_for_each_child(parent, NULL, + of_platform_device_depopulate); of_node_clear_flag(parent->of_node, OF_POPULATED_BUS); } } @@ -574,7 +592,6 @@ static int of_platform_notify(struct notifier_block *nb, { 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: @@ -612,7 +629,7 @@ static int of_platform_notify(struct notifier_block *nb, return NOTIFY_OK; /* no? not meant for us */
/* unregister takes one ref away */ - of_platform_device_destroy(&pdev->dev, &children_left); + of_platform_device_depopulate(&pdev->dev, NULL);
/* and put the reference of the find */ of_dev_put(pdev); diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index 956a100..a9017d3 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -63,6 +63,7 @@ extern struct platform_device *of_find_device_by_node(struct device_node *np); extern struct platform_device *of_platform_device_create(struct device_node *np, const char *bus_id, struct device *parent); +extern void of_platform_device_destroy(struct device *dev);
extern int of_platform_bus_probe(struct device_node *root, const struct of_device_id *matches,