diff options
Diffstat (limited to 'drivers/dca')
-rw-r--r-- | drivers/dca/dca-core.c | 131 | ||||
-rw-r--r-- | drivers/dca/dca-sysfs.c | 3 |
2 files changed, 105 insertions, 29 deletions
diff --git a/drivers/dca/dca-core.c b/drivers/dca/dca-core.c index bf5b92f86df..ec249d2db63 100644 --- a/drivers/dca/dca-core.c +++ b/drivers/dca/dca-core.c @@ -28,13 +28,29 @@ #include <linux/device.h> #include <linux/dca.h> -MODULE_LICENSE("GPL"); +#define DCA_VERSION "1.4" -/* For now we're assuming a single, global, DCA provider for the system. */ +MODULE_VERSION(DCA_VERSION); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Intel Corporation"); static DEFINE_SPINLOCK(dca_lock); -static struct dca_provider *global_dca = NULL; +static LIST_HEAD(dca_providers); + +static struct dca_provider *dca_find_provider_by_dev(struct device *dev) +{ + struct dca_provider *dca, *ret = NULL; + + list_for_each_entry(dca, &dca_providers, node) { + if ((!dev) || (dca->ops->dev_managed(dca, dev))) { + ret = dca; + break; + } + } + + return ret; +} /** * dca_add_requester - add a dca client to the list @@ -42,25 +58,39 @@ static struct dca_provider *global_dca = NULL; */ int dca_add_requester(struct device *dev) { - int err, slot; + struct dca_provider *dca; + int err, slot = -ENODEV; - if (!global_dca) - return -ENODEV; + if (!dev) + return -EFAULT; spin_lock(&dca_lock); - slot = global_dca->ops->add_requester(global_dca, dev); - spin_unlock(&dca_lock); - if (slot < 0) + + /* check if the requester has not been added already */ + dca = dca_find_provider_by_dev(dev); + if (dca) { + spin_unlock(&dca_lock); + return -EEXIST; + } + + list_for_each_entry(dca, &dca_providers, node) { + slot = dca->ops->add_requester(dca, dev); + if (slot >= 0) + break; + } + if (slot < 0) { + spin_unlock(&dca_lock); return slot; + } - err = dca_sysfs_add_req(global_dca, dev, slot); + err = dca_sysfs_add_req(dca, dev, slot); if (err) { - spin_lock(&dca_lock); - global_dca->ops->remove_requester(global_dca, dev); + dca->ops->remove_requester(dca, dev); spin_unlock(&dca_lock); return err; } + spin_unlock(&dca_lock); return 0; } EXPORT_SYMBOL_GPL(dca_add_requester); @@ -71,30 +101,78 @@ EXPORT_SYMBOL_GPL(dca_add_requester); */ int dca_remove_requester(struct device *dev) { + struct dca_provider *dca; int slot; - if (!global_dca) - return -ENODEV; + + if (!dev) + return -EFAULT; spin_lock(&dca_lock); - slot = global_dca->ops->remove_requester(global_dca, dev); - spin_unlock(&dca_lock); - if (slot < 0) + dca = dca_find_provider_by_dev(dev); + if (!dca) { + spin_unlock(&dca_lock); + return -ENODEV; + } + slot = dca->ops->remove_requester(dca, dev); + if (slot < 0) { + spin_unlock(&dca_lock); return slot; + } - dca_sysfs_remove_req(global_dca, slot); + dca_sysfs_remove_req(dca, slot); + + spin_unlock(&dca_lock); return 0; } EXPORT_SYMBOL_GPL(dca_remove_requester); /** - * dca_get_tag - return the dca tag for the given cpu + * dca_common_get_tag - return the dca tag (serves both new and old api) + * @dev - the device that wants dca service * @cpu - the cpuid as returned by get_cpu() */ -u8 dca_get_tag(int cpu) +u8 dca_common_get_tag(struct device *dev, int cpu) { - if (!global_dca) + struct dca_provider *dca; + u8 tag; + + spin_lock(&dca_lock); + + dca = dca_find_provider_by_dev(dev); + if (!dca) { + spin_unlock(&dca_lock); return -ENODEV; - return global_dca->ops->get_tag(global_dca, cpu); + } + tag = dca->ops->get_tag(dca, dev, cpu); + + spin_unlock(&dca_lock); + return tag; +} + +/** + * dca3_get_tag - return the dca tag to the requester device + * for the given cpu (new api) + * @dev - the device that wants dca service + * @cpu - the cpuid as returned by get_cpu() + */ +u8 dca3_get_tag(struct device *dev, int cpu) +{ + if (!dev) + return -EFAULT; + + return dca_common_get_tag(dev, cpu); +} +EXPORT_SYMBOL_GPL(dca3_get_tag); + +/** + * dca_get_tag - return the dca tag for the given cpu (old api) + * @cpu - the cpuid as returned by get_cpu() + */ +u8 dca_get_tag(int cpu) +{ + struct device *dev = NULL; + + return dca_common_get_tag(dev, cpu); } EXPORT_SYMBOL_GPL(dca_get_tag); @@ -140,12 +218,10 @@ int register_dca_provider(struct dca_provider *dca, struct device *dev) { int err; - if (global_dca) - return -EEXIST; err = dca_sysfs_add_provider(dca, dev); if (err) return err; - global_dca = dca; + list_add(&dca->node, &dca_providers); blocking_notifier_call_chain(&dca_provider_chain, DCA_PROVIDER_ADD, NULL); return 0; @@ -158,11 +234,9 @@ EXPORT_SYMBOL_GPL(register_dca_provider); */ void unregister_dca_provider(struct dca_provider *dca) { - if (!global_dca) - return; blocking_notifier_call_chain(&dca_provider_chain, DCA_PROVIDER_REMOVE, NULL); - global_dca = NULL; + list_del(&dca->node); dca_sysfs_remove_provider(dca); } EXPORT_SYMBOL_GPL(unregister_dca_provider); @@ -187,6 +261,7 @@ EXPORT_SYMBOL_GPL(dca_unregister_notify); static int __init dca_init(void) { + printk(KERN_ERR "dca service started, version %s\n", DCA_VERSION); return dca_sysfs_init(); } diff --git a/drivers/dca/dca-sysfs.c b/drivers/dca/dca-sysfs.c index 011328faa5f..3d47e9d8e34 100644 --- a/drivers/dca/dca-sysfs.c +++ b/drivers/dca/dca-sysfs.c @@ -13,9 +13,10 @@ static spinlock_t dca_idr_lock; int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot) { struct device *cd; + static int req_count; cd = device_create(dca_class, dca->cd, MKDEV(0, slot + 1), - "requester%d", slot); + "requester%d", req_count++); if (IS_ERR(cd)) return PTR_ERR(cd); return 0; |