Commit da389eac authored by David Vrabel's avatar David Vrabel Committed by David Vrabel

uwb: add the umc bus

The UMC bus is used for the capabilities exposed by a UWB Multi-interface
Controller as described in the WHCI specification.
Signed-off-by: default avatarDavid Vrabel <david.vrabel@csr.com>
parent 2f86c3e6
obj-$(CONFIG_UWB) += uwb.o
obj-$(CONFIG_UWB_WHCI) += umc.o
uwb-objs := \
address.o \
......@@ -18,3 +19,8 @@ uwb-objs := \
scan.o \
uwb-debug.o \
uwbd.o
umc-objs := \
umc-bus.o \
umc-dev.o \
umc-drv.o
/*
* 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");
/*
* UWB Multi-interface Controller device management.
*
* Copyright (C) 2007 Cambridge Silicon Radio Ltd.
*
* This file is released under the GNU GPL v2.
*/
#include <linux/kernel.h>
#include <linux/uwb/umc.h>
#define D_LOCAL 0
#include <linux/uwb/debug.h>
static void umc_device_release(struct device *dev)
{
struct umc_dev *umc = to_umc_dev(dev);
kfree(umc);
}
/**
* umc_device_create - allocate a child UMC device
* @parent: parent of the new UMC device.
* @n: index of the new device.
*
* The new UMC device will have a bus ID of the parent with '-n'
* appended.
*/
struct umc_dev *umc_device_create(struct device *parent, int n)
{
struct umc_dev *umc;
umc = kzalloc(sizeof(struct umc_dev), GFP_KERNEL);
if (umc) {
snprintf(umc->dev.bus_id, sizeof(umc->dev.bus_id), "%s-%d",
parent->bus_id, n);
umc->dev.parent = parent;
umc->dev.bus = &umc_bus_type;
umc->dev.release = umc_device_release;
umc->dev.dma_mask = parent->dma_mask;
}
return umc;
}
EXPORT_SYMBOL_GPL(umc_device_create);
/**
* umc_device_register - register a UMC device
* @umc: pointer to the UMC device
*
* The memory resource for the UMC device is acquired and the device
* registered with the system.
*/
int umc_device_register(struct umc_dev *umc)
{
int err;
d_fnstart(3, &umc->dev, "(umc_dev %p)\n", umc);
err = request_resource(umc->resource.parent, &umc->resource);
if (err < 0) {
dev_err(&umc->dev, "can't allocate resource range "
"%016Lx to %016Lx: %d\n",
(unsigned long long)umc->resource.start,
(unsigned long long)umc->resource.end,
err);
goto error_request_resource;
}
err = device_register(&umc->dev);
if (err < 0)
goto error_device_register;
d_fnend(3, &umc->dev, "(umc_dev %p) = 0\n", umc);
return 0;
error_device_register:
release_resource(&umc->resource);
error_request_resource:
d_fnend(3, &umc->dev, "(umc_dev %p) = %d\n", umc, err);
return err;
}
EXPORT_SYMBOL_GPL(umc_device_register);
/**
* umc_device_unregister - unregister a UMC device
* @umc: pointer to the UMC device
*
* First we unregister the device, make sure the driver can do it's
* resource release thing and then we try to release any left over
* resources. We take a ref to the device, to make sure it doesn't
* dissapear under our feet.
*/
void umc_device_unregister(struct umc_dev *umc)
{
struct device *dev;
if (!umc)
return;
dev = get_device(&umc->dev);
d_fnstart(3, dev, "(umc_dev %p)\n", umc);
device_unregister(&umc->dev);
release_resource(&umc->resource);
d_fnend(3, dev, "(umc_dev %p) = void\n", umc);
put_device(dev);
}
EXPORT_SYMBOL_GPL(umc_device_unregister);
/*
* UWB Multi-interface Controller driver management.
*
* Copyright (C) 2007 Cambridge Silicon Radio Ltd.
*
* This file is released under the GNU GPL v2.
*/
#include <linux/kernel.h>
#include <linux/uwb/umc.h>
int __umc_driver_register(struct umc_driver *umc_drv, struct module *module,
const char *mod_name)
{
umc_drv->driver.name = umc_drv->name;
umc_drv->driver.owner = module;
umc_drv->driver.mod_name = mod_name;
umc_drv->driver.bus = &umc_bus_type;
return driver_register(&umc_drv->driver);
}
EXPORT_SYMBOL_GPL(__umc_driver_register);
/**
* umc_driver_register - unregister a UMC capabiltity driver.
* @umc_drv: pointer to the driver.
*/
void umc_driver_unregister(struct umc_driver *umc_drv)
{
driver_unregister(&umc_drv->driver);
}
EXPORT_SYMBOL_GPL(umc_driver_unregister);
/*
* UWB Multi-interface Controller support.
*
* Copyright (C) 2007 Cambridge Silicon Radio Ltd.
*
* This file is released under the GPLv2
*
* UMC (UWB Multi-interface Controller) capabilities (e.g., radio
* controller, host controller) are presented as devices on the "umc"
* bus.
*
* The radio controller is not strictly a UMC capability but it's
* useful to present it as such.
*
* References:
*
* [WHCI] Wireless Host Controller Interface Specification for
* Certified Wireless Universal Serial Bus, revision 0.95.
*
* How this works is kind of convoluted but simple. The whci.ko driver
* loads when WHCI devices are detected. These WHCI devices expose
* many devices in the same PCI function (they couldn't have reused
* functions, no), so for each PCI function that exposes these many
* devices, whci ceates a umc_dev [whci_probe() -> whci_add_cap()]
* with umc_device_create() and adds it to the bus with
* umc_device_register().
*
* umc_device_register() calls device_register() which will push the
* bus management code to load your UMC driver's somehting_probe()
* that you have registered for that capability code.
*
* Now when the WHCI device is removed, whci_remove() will go over
* each umc_dev assigned to each of the PCI function's capabilities
* and through whci_del_cap() call umc_device_unregister() each
* created umc_dev. Of course, if you are bound to the device, your
* driver's something_remove() will be called.
*/
#ifndef _LINUX_UWB_UMC_H_
#define _LINUX_UWB_UMC_H_
#include <linux/device.h>
#include <linux/pci.h>
/*
* UMC capability IDs.
*
* 0x00 is reserved so use it for the radio controller device.
*
* [WHCI] table 2-8
*/
#define UMC_CAP_ID_WHCI_RC 0x00 /* radio controller */
#define UMC_CAP_ID_WHCI_WUSB_HC 0x01 /* WUSB host controller */
/**
* struct umc_dev - UMC capability device
*
* @version: version of the specification this capability conforms to.
* @cap_id: capability ID.
* @bar: PCI Bar (64 bit) where the resource lies
* @resource: register space resource.
* @irq: interrupt line.
*/
struct umc_dev {
u16 version;
u8 cap_id;
u8 bar;
struct resource resource;
unsigned irq;
struct device dev;
};
#define to_umc_dev(d) container_of(d, struct umc_dev, dev)
/**
* struct umc_driver - UMC capability driver
* @cap_id: supported capability ID.
* @match: driver specific capability matching function.
* @match_data: driver specific data for match() (e.g., a
* table of pci_device_id's if umc_match_pci_id() is used).
*/
struct umc_driver {
char *name;
u8 cap_id;
int (*match)(struct umc_driver *, struct umc_dev *);
const void *match_data;
int (*probe)(struct umc_dev *);
void (*remove)(struct umc_dev *);
int (*suspend)(struct umc_dev *, pm_message_t state);
int (*resume)(struct umc_dev *);
struct device_driver driver;
};
#define to_umc_driver(d) container_of(d, struct umc_driver, driver)
extern struct bus_type umc_bus_type;
struct umc_dev *umc_device_create(struct device *parent, int n);
int __must_check umc_device_register(struct umc_dev *umc);
void umc_device_unregister(struct umc_dev *umc);
int __must_check __umc_driver_register(struct umc_driver *umc_drv,
struct module *mod,
const char *mod_name);
/**
* umc_driver_register - register a UMC capabiltity driver.
* @umc_drv: pointer to the driver.
*/
static inline int __must_check umc_driver_register(struct umc_driver *umc_drv)
{
return __umc_driver_register(umc_drv, THIS_MODULE, KBUILD_MODNAME);
}
void umc_driver_unregister(struct umc_driver *umc_drv);
/*
* Utility function you can use to match (umc_driver->match) against a
* null-terminated array of 'struct pci_device_id' in
* umc_driver->match_data.
*/
int umc_match_pci_id(struct umc_driver *umc_drv, struct umc_dev *umc);
/**
* umc_parent_pci_dev - return the UMC's parent PCI device or NULL if none
* @umc_dev: UMC device whose parent PCI device we are looking for
*
* DIRTY!!! DON'T RELY ON THIS
*
* FIXME: This is as dirty as it gets, but we need some way to check
* the correct type of umc_dev->parent (so that for example, we can
* cast to pci_dev). Casting to pci_dev is necesary because at some
* point we need to request resources from the device. Mapping is
* easily over come (ioremap and stuff are bus agnostic), but hooking
* up to some error handlers (such as pci error handlers) might need
* this.
*
* THIS might (probably will) be removed in the future, so don't count
* on it.
*/
static inline struct pci_dev *umc_parent_pci_dev(struct umc_dev *umc_dev)
{
struct pci_dev *pci_dev = NULL;
if (umc_dev->dev.parent->bus == &pci_bus_type)
pci_dev = to_pci_dev(umc_dev->dev.parent);
return pci_dev;
}
/**
* umc_dev_get() - reference a UMC device.
* @umc_dev: Pointer to UMC device.
*
* NOTE: we are assuming in this whole scheme that the parent device
* is referenced at _probe() time and unreferenced at _remove()
* time by the parent's subsystem.
*/
static inline struct umc_dev *umc_dev_get(struct umc_dev *umc_dev)
{
get_device(&umc_dev->dev);
return umc_dev;
}
/**
* umc_dev_put() - unreference a UMC device.
* @umc_dev: Pointer to UMC device.
*/
static inline void umc_dev_put(struct umc_dev *umc_dev)
{
put_device(&umc_dev->dev);
}
/**
* umc_set_drvdata - set UMC device's driver data.
* @umc_dev: Pointer to UMC device.
* @data: Data to set.
*/
static inline void umc_set_drvdata(struct umc_dev *umc_dev, void *data)
{
dev_set_drvdata(&umc_dev->dev, data);
}
/**
* umc_get_drvdata - recover UMC device's driver data.
* @umc_dev: Pointer to UMC device.
*/
static inline void *umc_get_drvdata(struct umc_dev *umc_dev)
{
return dev_get_drvdata(&umc_dev->dev);
}
int umc_controller_reset(struct umc_dev *umc);
#endif /* #ifndef _LINUX_UWB_UMC_H_ */
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