diff options
Diffstat (limited to 'drivers/uwb/umc-bus.c')
| -rw-r--r-- | drivers/uwb/umc-bus.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/drivers/uwb/umc-bus.c b/drivers/uwb/umc-bus.c new file mode 100644 index 000000000000..2d8d62d9f53e --- /dev/null +++ b/drivers/uwb/umc-bus.c @@ -0,0 +1,218 @@ +/* + * Bus for UWB Multi-interface Controller capabilities. + * + * Copyright (C) 2007 Cambridge Silicon Radio Ltd. + * + * This file is released under the GNU GPL v2. + */ +#include <linux/kernel.h> +#include <linux/sysfs.h> +#include <linux/workqueue.h> +#include <linux/uwb/umc.h> +#include <linux/pci.h> + +static int umc_bus_unbind_helper(struct device *dev, void *data) +{ + struct device *parent = data; + + if (dev->parent == parent && dev->driver) + device_release_driver(dev); + return 0; +} + +/** + * umc_controller_reset - reset the whole UMC controller + * @umc: the UMC device for the radio controller. + * + * Drivers will be unbound from all UMC devices belonging to the + * controller and then the radio controller will be rebound. The + * radio controller is expected to do a full hardware reset when it is + * probed. + * + * If this is called while a probe() or remove() is in progress it + * will return -EAGAIN and not perform the reset. + */ +int umc_controller_reset(struct umc_dev *umc) +{ + struct device *parent = umc->dev.parent; + int ret; + + if (down_trylock(&parent->sem)) + return -EAGAIN; + bus_for_each_dev(&umc_bus_type, NULL, parent, umc_bus_unbind_helper); + ret = device_attach(&umc->dev); + if (ret == 1) + ret = 0; + up(&parent->sem); + + return ret; +} +EXPORT_SYMBOL_GPL(umc_controller_reset); + +/** + * umc_match_pci_id - match a UMC driver to a UMC device's parent PCI device. + * @umc_drv: umc driver with match_data pointing to a zero-terminated + * table of pci_device_id's. + * @umc: umc device whose parent is to be matched. + */ +int umc_match_pci_id(struct umc_driver *umc_drv, struct umc_dev *umc) +{ + const struct pci_device_id *id_table = umc_drv->match_data; + struct pci_dev *pci; + + if (umc->dev.parent->bus != &pci_bus_type) + return 0; + + pci = to_pci_dev(umc->dev.parent); + return pci_match_id(id_table, pci) != NULL; +} +EXPORT_SYMBOL_GPL(umc_match_pci_id); + +static int umc_bus_rescan_helper(struct device *dev, void *data) +{ + int ret = 0; + + if (!dev->driver) + ret = device_attach(dev); + + return ret < 0 ? ret : 0; +} + +static void umc_bus_rescan(void) +{ + int err; + + /* + * We can't use bus_rescan_devices() here as it deadlocks when + * it tries to retake the dev->parent semaphore. + */ + err = bus_for_each_dev(&umc_bus_type, NULL, NULL, umc_bus_rescan_helper); + if (err < 0) + printk(KERN_WARNING "%s: rescan of bus failed: %d\n", + KBUILD_MODNAME, err); +} + +static int umc_bus_match(struct device *dev, struct device_driver *drv) +{ + struct umc_dev *umc = to_umc_dev(dev); + struct umc_driver *umc_driver = to_umc_driver(drv); + + if (umc->cap_id == umc_driver->cap_id) { + if (umc_driver->match) + return umc_driver->match(umc_driver, umc); + else + return 1; + } + return 0; +} + +static int umc_device_probe(struct device *dev) +{ + struct umc_dev *umc; + struct umc_driver *umc_driver; + int err; + + umc_driver = to_umc_driver(dev->driver); + umc = to_umc_dev(dev); + + get_device(dev); + err = umc_driver->probe(umc); + if (err) + put_device(dev); + else + umc_bus_rescan(); + + return err; +} + +static int umc_device_remove(struct device *dev) +{ + struct umc_dev *umc; + struct umc_driver *umc_driver; + + umc_driver = to_umc_driver(dev->driver); + umc = to_umc_dev(dev); + + umc_driver->remove(umc); + put_device(dev); + return 0; +} + +static int umc_device_suspend(struct device *dev, pm_message_t state) +{ + struct umc_dev *umc; + struct umc_driver *umc_driver; + int err = 0; + + umc = to_umc_dev(dev); + + if (dev->driver) { + umc_driver = to_umc_driver(dev->driver); + if (umc_driver->suspend) + err = umc_driver->suspend(umc, state); + } + return err; +} + +static int umc_device_resume(struct device *dev) +{ + struct umc_dev *umc; + struct umc_driver *umc_driver; + int err = 0; + + umc = to_umc_dev(dev); + + if (dev->driver) { + umc_driver = to_umc_driver(dev->driver); + if (umc_driver->resume) + err = umc_driver->resume(umc); + } + return err; +} + +static ssize_t capability_id_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct umc_dev *umc = to_umc_dev(dev); + + return sprintf(buf, "0x%02x\n", umc->cap_id); +} + +static ssize_t version_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct umc_dev *umc = to_umc_dev(dev); + + return sprintf(buf, "0x%04x\n", umc->version); +} + +static struct device_attribute umc_dev_attrs[] = { + __ATTR_RO(capability_id), + __ATTR_RO(version), + __ATTR_NULL, +}; + +struct bus_type umc_bus_type = { + .name = "umc", + .match = umc_bus_match, + .probe = umc_device_probe, + .remove = umc_device_remove, + .suspend = umc_device_suspend, + .resume = umc_device_resume, + .dev_attrs = umc_dev_attrs, +}; +EXPORT_SYMBOL_GPL(umc_bus_type); + +static int __init umc_bus_init(void) +{ + return bus_register(&umc_bus_type); +} +module_init(umc_bus_init); + +static void __exit umc_bus_exit(void) +{ + bus_unregister(&umc_bus_type); +} +module_exit(umc_bus_exit); + +MODULE_DESCRIPTION("UWB Multi-interface Controller capability bus"); +MODULE_AUTHOR("Cambridge Silicon Radio Ltd."); +MODULE_LICENSE("GPL"); |