| Message ID | 1399981836-24837-1-git-send-email-pawel.moll@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 13, 2014 at 6:50 AM, Pawel Moll <pawel.moll@arm.com> wrote: > Drivers can us of_platform_populate() to create > platform devices for children of the device > main node (this can particularly happen in case > of MFD devices). Unfortunately, there was no > standard way of removing such sub-devices when > the main one is being removed. > > This patch adds of_platform_depopulate() as > a complementary operation for the _populate() > one. It removes all platform and amba devices > that have been created from the Device Tree, > but leaves all other ones untouched (returning > -EBUSY in such case). > > Signed-off-by: Pawel Moll <pawel.moll@arm.com> > --- > drivers/of/platform.c | 52 +++++++++++++++++++++++++++++++++++++++++++++ > include/linux/of_platform.h | 5 +++++ > 2 files changed, 57 insertions(+) > > diff --git a/drivers/of/platform.c b/drivers/of/platform.c > index 2d0c8b7..b5c49c3 100644 > --- a/drivers/of/platform.c > +++ b/drivers/of/platform.c > @@ -495,4 +495,56 @@ 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) > +{ > + int *parents_children_left = data; You are not really tracking how many children are left, so this can just be a bool. > + int my_children_left = 0; > + > + /* Do not touch devices not populated from the device tree */ > + if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) { > + (*parents_children_left)++; > + return 0; > + } > + > + device_for_each_child(dev, &my_children_left, > + of_platform_device_destroy); Can't you call of_platform_depopulate here? > + if (my_children_left) { > + (*parents_children_left)++; > + return 0; > + }
On Tue, 2014-05-13 at 14:19 +0100, Rob Herring wrote: > On Tue, May 13, 2014 at 6:50 AM, Pawel Moll <pawel.moll@arm.com> wrote: > > Drivers can us of_platform_populate() to create > > platform devices for children of the device > > main node (this can particularly happen in case > > of MFD devices). Unfortunately, there was no > > standard way of removing such sub-devices when > > the main one is being removed. > > > > This patch adds of_platform_depopulate() as > > a complementary operation for the _populate() > > one. It removes all platform and amba devices > > that have been created from the Device Tree, > > but leaves all other ones untouched (returning > > -EBUSY in such case). > > > > Signed-off-by: Pawel Moll <pawel.moll@arm.com> > > --- > > drivers/of/platform.c | 52 +++++++++++++++++++++++++++++++++++++++++++++ > > include/linux/of_platform.h | 5 +++++ > > 2 files changed, 57 insertions(+) > > > > diff --git a/drivers/of/platform.c b/drivers/of/platform.c > > index 2d0c8b7..b5c49c3 100644 > > --- a/drivers/of/platform.c > > +++ b/drivers/of/platform.c > > @@ -495,4 +495,56 @@ 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) > > +{ > > + int *parents_children_left = data; > > You are not really tracking how many children are left, so this can > just be a bool. That's true. > > + int my_children_left = 0; > > + > > + /* Do not touch devices not populated from the device tree */ > > + if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) { > > + (*parents_children_left)++; > > + return 0; > > + } > > + > > + device_for_each_child(dev, &my_children_left, > > + of_platform_device_destroy); > > Can't you call of_platform_depopulate here? ... and check its result instead of ? I guess I could. Will have a look how it looks like. Pawe?
diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 2d0c8b7..b5c49c3 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -495,4 +495,56 @@ 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) +{ + int *parents_children_left = data; + int my_children_left = 0; + + /* Do not touch devices not populated from the device tree */ + if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) { + (*parents_children_left)++; + return 0; + } + + device_for_each_child(dev, &my_children_left, + of_platform_device_destroy); + if (my_children_left) { + (*parents_children_left)++; + return 0; + } + + if (dev->bus == &platform_bus_type) + platform_device_unregister(to_platform_device(dev)); + else if (dev->bus == &amba_bustype) + amba_device_unregister(to_amba_device(dev)); + else + (*parents_children_left)++; + + 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) +{ + int children_left = 0; + + 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_platform.h b/include/linux/of_platform.h index 05cb4a9..b1010ee 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 */
Drivers can us of_platform_populate() to create platform devices for children of the device main node (this can particularly happen in case of MFD devices). Unfortunately, there was no standard way of removing such sub-devices when the main one is being removed. This patch adds of_platform_depopulate() as a complementary operation for the _populate() one. It removes all platform and amba devices that have been created from the Device Tree, but leaves all other ones untouched (returning -EBUSY in such case). Signed-off-by: Pawel Moll <pawel.moll@arm.com> --- drivers/of/platform.c | 52 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_platform.h | 5 +++++ 2 files changed, 57 insertions(+)