diff options
Diffstat (limited to 'drivers/base/core.c')
| -rw-r--r-- | drivers/base/core.c | 106 |
1 files changed, 87 insertions, 19 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c index 919daa7cd5b1..74dda4f697f9 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -118,6 +118,56 @@ static const struct sysfs_ops dev_sysfs_ops = { .store = dev_attr_store, }; +#define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr) + +ssize_t device_store_ulong(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct dev_ext_attribute *ea = to_ext_attr(attr); + char *end; + unsigned long new = simple_strtoul(buf, &end, 0); + if (end == buf) + return -EINVAL; + *(unsigned long *)(ea->var) = new; + /* Always return full write size even if we didn't consume all */ + return size; +} +EXPORT_SYMBOL_GPL(device_store_ulong); + +ssize_t device_show_ulong(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct dev_ext_attribute *ea = to_ext_attr(attr); + return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var)); +} +EXPORT_SYMBOL_GPL(device_show_ulong); + +ssize_t device_store_int(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct dev_ext_attribute *ea = to_ext_attr(attr); + char *end; + long new = simple_strtol(buf, &end, 0); + if (end == buf || new > INT_MAX || new < INT_MIN) + return -EINVAL; + *(int *)(ea->var) = new; + /* Always return full write size even if we didn't consume all */ + return size; +} +EXPORT_SYMBOL_GPL(device_store_int); + +ssize_t device_show_int(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct dev_ext_attribute *ea = to_ext_attr(attr); + + return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var)); +} +EXPORT_SYMBOL_GPL(device_show_int); /** * device_release - free device structure. @@ -198,7 +248,7 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj, if (MAJOR(dev->devt)) { const char *tmp; const char *name; - mode_t mode = 0; + umode_t mode = 0; add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt)); add_uevent_var(env, "MINOR=%u", MINOR(dev->devt)); @@ -464,7 +514,7 @@ static ssize_t show_dev(struct device *dev, struct device_attribute *attr, static struct device_attribute devt_attr = __ATTR(dev, S_IRUGO, show_dev, NULL); -/* kset to create /sys/devices/ */ +/* /sys/devices/ */ struct kset *devices_kset; /** @@ -582,6 +632,11 @@ static void klist_children_put(struct klist_node *n) * may be used for reference counting of @dev after calling this * function. * + * All fields in @dev must be initialized by the caller to 0, except + * for those explicitly set to some other value. The simplest + * approach is to use kzalloc() to allocate the structure containing + * @dev. + * * NOTE: Use put_device() to give up your reference instead of freeing * @dev directly once you have called this function. */ @@ -711,6 +766,10 @@ static struct kobject *get_device_parent(struct device *dev, return k; } + /* subsystems can specify a default root directory for their devices */ + if (!parent && dev->bus && dev->bus->dev_root) + return &dev->bus->dev_root->kobj; + if (parent) return &parent->kobj; return NULL; @@ -731,14 +790,6 @@ static void cleanup_device_parent(struct device *dev) cleanup_glue_dir(dev, dev->kobj.parent); } -static void setup_parent(struct device *dev, struct device *parent) -{ - struct kobject *kobj; - kobj = get_device_parent(dev, parent); - if (kobj) - dev->kobj.parent = kobj; -} - static int device_add_class_symlinks(struct device *dev) { int error; @@ -884,6 +935,13 @@ int device_private_init(struct device *dev) * to the global and sibling lists for the device, then * adds it to the other relevant subsystems of the driver model. * + * Do not call this routine or device_register() more than once for + * any device structure. The driver model core is not designed to work + * with devices that get unregistered and then spring back to life. + * (Among other things, it's very hard to guarantee that all references + * to the previous incarnation of @dev have been dropped.) Allocate + * and register a fresh new struct device instead. + * * NOTE: _Never_ directly free @dev after calling this function, even * if it returned an error! Always use put_device() to give up your * reference instead. @@ -891,6 +949,7 @@ int device_private_init(struct device *dev) int device_add(struct device *dev) { struct device *parent = NULL; + struct kobject *kobj; struct class_interface *class_intf; int error = -EINVAL; @@ -914,6 +973,10 @@ int device_add(struct device *dev) dev->init_name = NULL; } + /* subsystems can specify simple device enumeration */ + if (!dev_name(dev) && dev->bus && dev->bus->dev_name) + dev_set_name(dev, "%s%u", dev->bus->dev_name, dev->id); + if (!dev_name(dev)) { error = -EINVAL; goto name_error; @@ -922,7 +985,9 @@ int device_add(struct device *dev) pr_debug("device: '%s': %s\n", dev_name(dev), __func__); parent = get_device(dev->parent); - setup_parent(dev, parent); + kobj = get_device_parent(dev, parent); + if (kobj) + dev->kobj.parent = kobj; /* use parent numa_node */ if (parent) @@ -969,7 +1034,7 @@ int device_add(struct device *dev) device_pm_add(dev); /* Notify clients of device addition. This call must come - * after dpm_sysf_add() and before kobject_uevent(). + * after dpm_sysfs_add() and before kobject_uevent(). */ if (dev->bus) blocking_notifier_call_chain(&dev->bus->p->bus_notifier, @@ -982,17 +1047,17 @@ int device_add(struct device *dev) &parent->p->klist_children); if (dev->class) { - mutex_lock(&dev->class->p->class_mutex); + mutex_lock(&dev->class->p->mutex); /* tie the class to the device */ klist_add_tail(&dev->knode_class, &dev->class->p->klist_devices); /* notify any interfaces that the device is here */ list_for_each_entry(class_intf, - &dev->class->p->class_interfaces, node) + &dev->class->p->interfaces, node) if (class_intf->add_dev) class_intf->add_dev(dev, class_intf); - mutex_unlock(&dev->class->p->class_mutex); + mutex_unlock(&dev->class->p->mutex); } done: put_device(dev); @@ -1037,6 +1102,9 @@ name_error: * have a clearly defined need to use and refcount the device * before it is added to the hierarchy. * + * For more information, see the kerneldoc for device_initialize() + * and device_add(). + * * NOTE: _Never_ directly free @dev after calling this function, even * if it returned an error! Always use put_device() to give up the * reference initialized in this function instead. @@ -1107,15 +1175,15 @@ void device_del(struct device *dev) if (dev->class) { device_remove_class_symlinks(dev); - mutex_lock(&dev->class->p->class_mutex); + mutex_lock(&dev->class->p->mutex); /* notify any interfaces that the device is now gone */ list_for_each_entry(class_intf, - &dev->class->p->class_interfaces, node) + &dev->class->p->interfaces, node) if (class_intf->remove_dev) class_intf->remove_dev(dev, class_intf); /* remove the device from the class list */ klist_del(&dev->knode_class); - mutex_unlock(&dev->class->p->class_mutex); + mutex_unlock(&dev->class->p->mutex); } device_remove_file(dev, &uevent_attr); device_remove_attrs(dev); @@ -1182,7 +1250,7 @@ static struct device *next_device(struct klist_iter *i) * freed by the caller. */ const char *device_get_devnode(struct device *dev, - mode_t *mode, const char **tmp) + umode_t *mode, const char **tmp) { char *s; |