diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-01-07 12:03:30 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-01-07 12:03:30 -0800 |
commit | 7affca3537d74365128e477b40c529d6f2fe86c8 (patch) | |
tree | 20be92bd240029182fc89c2c4f25401b7715dcae /drivers/base/bus.c | |
parent | 356b95424cfb456e14a59eaa579422ce014c424b (diff) | |
parent | ff4b8a57f0aaa2882d444ca44b2b9b333d22a4df (diff) |
Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
arm: fix up some samsung merge sysdev conversion problems
firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
Drivers:hv: Fix a bug in vmbus_driver_unregister()
driver core: remove __must_check from device_create_file
debugfs: add missing #ifdef HAS_IOMEM
arm: time.h: remove device.h #include
driver-core: remove sysdev.h usage.
clockevents: remove sysdev.h
arm: convert sysdev_class to a regular subsystem
arm: leds: convert sysdev_class to a regular subsystem
kobject: remove kset_find_obj_hinted()
m86k: gpio - convert sysdev_class to a regular subsystem
mips: txx9_sram - convert sysdev_class to a regular subsystem
mips: 7segled - convert sysdev_class to a regular subsystem
sh: dma - convert sysdev_class to a regular subsystem
sh: intc - convert sysdev_class to a regular subsystem
power: suspend - convert sysdev_class to a regular subsystem
power: qe_ic - convert sysdev_class to a regular subsystem
power: cmm - convert sysdev_class to a regular subsystem
s390: time - convert sysdev_class to a regular subsystem
...
Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
- arch/arm/mach-exynos/cpu.c
- arch/arm/mach-exynos/irq-eint.c
- arch/arm/mach-s3c64xx/common.c
- arch/arm/mach-s3c64xx/cpu.c
- arch/arm/mach-s5p64x0/cpu.c
- arch/arm/mach-s5pv210/common.c
- arch/arm/plat-samsung/include/plat/cpu.h
- arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
Diffstat (limited to 'drivers/base/bus.c')
-rw-r--r-- | drivers/base/bus.c | 293 |
1 files changed, 274 insertions, 19 deletions
diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 000e7b2006f..99dc5921e1d 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -16,9 +16,14 @@ #include <linux/slab.h> #include <linux/init.h> #include <linux/string.h> +#include <linux/mutex.h> #include "base.h" #include "power/power.h" +/* /sys/devices/system */ +/* FIXME: make static after drivers/base/sys.c is deleted */ +struct kset *system_kset; + #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) /* @@ -360,6 +365,47 @@ struct device *bus_find_device_by_name(struct bus_type *bus, } EXPORT_SYMBOL_GPL(bus_find_device_by_name); +/** + * subsys_find_device_by_id - find a device with a specific enumeration number + * @subsys: subsystem + * @id: index 'id' in struct device + * @hint: device to check first + * + * Check the hint's next object and if it is a match return it directly, + * otherwise, fall back to a full list search. Either way a reference for + * the returned object is taken. + */ +struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id, + struct device *hint) +{ + struct klist_iter i; + struct device *dev; + + if (!subsys) + return NULL; + + if (hint) { + klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus); + dev = next_device(&i); + if (dev && dev->id == id && get_device(dev)) { + klist_iter_exit(&i); + return dev; + } + klist_iter_exit(&i); + } + + klist_iter_init_node(&subsys->p->klist_devices, &i, NULL); + while ((dev = next_device(&i))) { + if (dev->id == id && get_device(dev)) { + klist_iter_exit(&i); + return dev; + } + } + klist_iter_exit(&i); + return NULL; +} +EXPORT_SYMBOL_GPL(subsys_find_device_by_id); + static struct device_driver *next_driver(struct klist_iter *i) { struct klist_node *n = klist_next(i); @@ -487,38 +533,59 @@ out_put: void bus_probe_device(struct device *dev) { struct bus_type *bus = dev->bus; + struct subsys_interface *sif; int ret; - if (bus && bus->p->drivers_autoprobe) { + if (!bus) + return; + + if (bus->p->drivers_autoprobe) { ret = device_attach(dev); WARN_ON(ret < 0); } + + mutex_lock(&bus->p->mutex); + list_for_each_entry(sif, &bus->p->interfaces, node) + if (sif->add_dev) + sif->add_dev(dev, sif); + mutex_unlock(&bus->p->mutex); } /** * bus_remove_device - remove device from bus * @dev: device to be removed * - * - Remove symlink from bus's directory. + * - Remove device from all interfaces. + * - Remove symlink from bus' directory. * - Delete device from bus's list. * - Detach from its driver. * - Drop reference taken in bus_add_device(). */ void bus_remove_device(struct device *dev) { - if (dev->bus) { - sysfs_remove_link(&dev->kobj, "subsystem"); - sysfs_remove_link(&dev->bus->p->devices_kset->kobj, - dev_name(dev)); - device_remove_attrs(dev->bus, dev); - if (klist_node_attached(&dev->p->knode_bus)) - klist_del(&dev->p->knode_bus); - - pr_debug("bus: '%s': remove device %s\n", - dev->bus->name, dev_name(dev)); - device_release_driver(dev); - bus_put(dev->bus); - } + struct bus_type *bus = dev->bus; + struct subsys_interface *sif; + + if (!bus) + return; + + mutex_lock(&bus->p->mutex); + list_for_each_entry(sif, &bus->p->interfaces, node) + if (sif->remove_dev) + sif->remove_dev(dev, sif); + mutex_unlock(&bus->p->mutex); + + sysfs_remove_link(&dev->kobj, "subsystem"); + sysfs_remove_link(&dev->bus->p->devices_kset->kobj, + dev_name(dev)); + device_remove_attrs(dev->bus, dev); + if (klist_node_attached(&dev->p->knode_bus)) + klist_del(&dev->p->knode_bus); + + pr_debug("bus: '%s': remove device %s\n", + dev->bus->name, dev_name(dev)); + device_release_driver(dev); + bus_put(dev->bus); } static int driver_add_attrs(struct bus_type *bus, struct device_driver *drv) @@ -847,14 +914,14 @@ static ssize_t bus_uevent_store(struct bus_type *bus, static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); /** - * bus_register - register a bus with the system. + * __bus_register - register a driver-core subsystem * @bus: bus. * * Once we have that, we registered the bus with the kobject * infrastructure, then register the children subsystems it has: - * the devices and drivers that belong to the bus. + * the devices and drivers that belong to the subsystem. */ -int bus_register(struct bus_type *bus) +int __bus_register(struct bus_type *bus, struct lock_class_key *key) { int retval; struct subsys_private *priv; @@ -898,6 +965,8 @@ int bus_register(struct bus_type *bus) goto bus_drivers_fail; } + INIT_LIST_HEAD(&priv->interfaces); + __mutex_init(&priv->mutex, "subsys mutex", key); klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); klist_init(&priv->klist_drivers, NULL, NULL); @@ -927,7 +996,7 @@ out: bus->p = NULL; return retval; } -EXPORT_SYMBOL_GPL(bus_register); +EXPORT_SYMBOL_GPL(__bus_register); /** * bus_unregister - remove a bus from the system @@ -939,6 +1008,8 @@ EXPORT_SYMBOL_GPL(bus_register); void bus_unregister(struct bus_type *bus) { pr_debug("bus: '%s': unregistering\n", bus->name); + if (bus->dev_root) + device_unregister(bus->dev_root); bus_remove_attrs(bus); remove_probe_files(bus); kset_unregister(bus->p->drivers_kset); @@ -1028,10 +1099,194 @@ void bus_sort_breadthfirst(struct bus_type *bus, } EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); +/** + * subsys_dev_iter_init - initialize subsys device iterator + * @iter: subsys iterator to initialize + * @subsys: the subsys we wanna iterate over + * @start: the device to start iterating from, if any + * @type: device_type of the devices to iterate over, NULL for all + * + * Initialize subsys iterator @iter such that it iterates over devices + * of @subsys. If @start is set, the list iteration will start there, + * otherwise if it is NULL, the iteration starts at the beginning of + * the list. + */ +void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys, + struct device *start, const struct device_type *type) +{ + struct klist_node *start_knode = NULL; + + if (start) + start_knode = &start->p->knode_bus; + klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode); + iter->type = type; +} +EXPORT_SYMBOL_GPL(subsys_dev_iter_init); + +/** + * subsys_dev_iter_next - iterate to the next device + * @iter: subsys iterator to proceed + * + * Proceed @iter to the next device and return it. Returns NULL if + * iteration is complete. + * + * The returned device is referenced and won't be released till + * iterator is proceed to the next device or exited. The caller is + * free to do whatever it wants to do with the device including + * calling back into subsys code. + */ +struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter) +{ + struct klist_node *knode; + struct device *dev; + + for (;;) { + knode = klist_next(&iter->ki); + if (!knode) + return NULL; + dev = container_of(knode, struct device_private, knode_bus)->device; + if (!iter->type || iter->type == dev->type) + return dev; + } +} +EXPORT_SYMBOL_GPL(subsys_dev_iter_next); + +/** + * subsys_dev_iter_exit - finish iteration + * @iter: subsys iterator to finish + * + * Finish an iteration. Always call this function after iteration is + * complete whether the iteration ran till the end or not. + */ +void subsys_dev_iter_exit(struct subsys_dev_iter *iter) +{ + klist_iter_exit(&iter->ki); +} +EXPORT_SYMBOL_GPL(subsys_dev_iter_exit); + +int subsys_interface_register(struct subsys_interface *sif) +{ + struct bus_type *subsys; + struct subsys_dev_iter iter; + struct device *dev; + + if (!sif || !sif->subsys) + return -ENODEV; + + subsys = bus_get(sif->subsys); + if (!subsys) + return -EINVAL; + + mutex_lock(&subsys->p->mutex); + list_add_tail(&sif->node, &subsys->p->interfaces); + if (sif->add_dev) { + subsys_dev_iter_init(&iter, subsys, NULL, NULL); + while ((dev = subsys_dev_iter_next(&iter))) + sif->add_dev(dev, sif); + subsys_dev_iter_exit(&iter); + } + mutex_unlock(&subsys->p->mutex); + + return 0; +} +EXPORT_SYMBOL_GPL(subsys_interface_register); + +void subsys_interface_unregister(struct subsys_interface *sif) +{ + struct bus_type *subsys = sif->subsys; + struct subsys_dev_iter iter; + struct device *dev; + + if (!sif) + return; + + mutex_lock(&subsys->p->mutex); + list_del_init(&sif->node); + if (sif->remove_dev) { + subsys_dev_iter_init(&iter, subsys, NULL, NULL); + while ((dev = subsys_dev_iter_next(&iter))) + sif->remove_dev(dev, sif); + subsys_dev_iter_exit(&iter); + } + mutex_unlock(&subsys->p->mutex); + + bus_put(subsys); +} +EXPORT_SYMBOL_GPL(subsys_interface_unregister); + +static void system_root_device_release(struct device *dev) +{ + kfree(dev); +} +/** + * subsys_system_register - register a subsystem at /sys/devices/system/ + * @subsys - system subsystem + * @groups - default attributes for the root device + * + * All 'system' subsystems have a /sys/devices/system/<name> root device + * with the name of the subsystem. The root device can carry subsystem- + * wide attributes. All registered devices are below this single root + * device and are named after the subsystem with a simple enumeration + * number appended. The registered devices are not explicitely named; + * only 'id' in the device needs to be set. + * + * Do not use this interface for anything new, it exists for compatibility + * with bad ideas only. New subsystems should use plain subsystems; and + * add the subsystem-wide attributes should be added to the subsystem + * directory itself and not some create fake root-device placed in + * /sys/devices/system/<name>. + */ +int subsys_system_register(struct bus_type *subsys, + const struct attribute_group **groups) +{ + struct device *dev; + int err; + + err = bus_register(subsys); + if (err < 0) + return err; + + dev = kzalloc(sizeof(struct device), GFP_KERNEL); + if (!dev) { + err = -ENOMEM; + goto err_dev; + } + + err = dev_set_name(dev, "%s", subsys->name); + if (err < 0) + goto err_name; + + dev->kobj.parent = &system_kset->kobj; + dev->groups = groups; + dev->release = system_root_device_release; + + err = device_register(dev); + if (err < 0) + goto err_dev_reg; + + subsys->dev_root = dev; + return 0; + +err_dev_reg: + put_device(dev); + dev = NULL; +err_name: + kfree(dev); +err_dev: + bus_unregister(subsys); + return err; +} +EXPORT_SYMBOL_GPL(subsys_system_register); + int __init buses_init(void) { bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); if (!bus_kset) return -ENOMEM; + + system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj); + if (!system_kset) + return -ENOMEM; + return 0; } |