Commit 3a6f82f7 authored by Jiri Slaby's avatar Jiri Slaby Committed by Jiri Kosina

HID: add dynids facility

Allow adding new devices to the hid drivers on the fly without
a need of kernel recompilation.

Now, one can test a driver e.g. by:
echo 0003:045E:00F0.0003 > ../generic-usb/unbind
echo 0003 045E 00F0 > new_id
from some driver subdir.
Signed-off-by: default avatarJiri Slaby <jirislaby@gmail.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 898089d0
......@@ -1304,12 +1304,92 @@ static const struct hid_device_id hid_blacklist[] = {
{ }
};
struct hid_dynid {
struct list_head list;
struct hid_device_id id;
};
/**
* store_new_id - add a new HID device ID to this driver and re-probe devices
* @driver: target device driver
* @buf: buffer for scanning device ID data
* @count: input size
*
* Adds a new dynamic hid device ID to this driver,
* and causes the driver to probe for all devices again.
*/
static ssize_t store_new_id(struct device_driver *drv, const char *buf,
size_t count)
{
struct hid_driver *hdrv = container_of(drv, struct hid_driver, driver);
struct hid_dynid *dynid;
__u32 bus, vendor, product;
unsigned long driver_data = 0;
int ret;
ret = sscanf(buf, "%x %x %x %lx",
&bus, &vendor, &product, &driver_data);
if (ret < 3)
return -EINVAL;
dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
if (!dynid)
return -ENOMEM;
dynid->id.bus = bus;
dynid->id.vendor = vendor;
dynid->id.product = product;
dynid->id.driver_data = driver_data;
spin_lock(&hdrv->dyn_lock);
list_add_tail(&dynid->list, &hdrv->dyn_list);
spin_unlock(&hdrv->dyn_lock);
ret = 0;
if (get_driver(&hdrv->driver)) {
ret = driver_attach(&hdrv->driver);
put_driver(&hdrv->driver);
}
return ret ? : count;
}
static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
static void hid_free_dynids(struct hid_driver *hdrv)
{
struct hid_dynid *dynid, *n;
spin_lock(&hdrv->dyn_lock);
list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) {
list_del(&dynid->list);
kfree(dynid);
}
spin_unlock(&hdrv->dyn_lock);
}
static const struct hid_device_id *hid_match_device(struct hid_device *hdev,
struct hid_driver *hdrv)
{
struct hid_dynid *dynid;
spin_lock(&hdrv->dyn_lock);
list_for_each_entry(dynid, &hdrv->dyn_list, list) {
if (hid_match_one_id(hdev, &dynid->id)) {
spin_unlock(&hdrv->dyn_lock);
return &dynid->id;
}
}
spin_unlock(&hdrv->dyn_lock);
return hid_match_id(hdev, hdrv->id_table);
}
static int hid_bus_match(struct device *dev, struct device_driver *drv)
{
struct hid_driver *hdrv = container_of(drv, struct hid_driver, driver);
struct hid_device *hdev = container_of(dev, struct hid_device, dev);
if (!hid_match_id(hdev, hdrv->id_table))
if (!hid_match_device(hdev, hdrv))
return 0;
/* generic wants all non-blacklisted */
......@@ -1328,7 +1408,7 @@ static int hid_device_probe(struct device *dev)
int ret = 0;
if (!hdev->driver) {
id = hid_match_id(hdev, hdrv->id_table);
id = hid_match_device(hdev, hdrv);
if (id == NULL)
return -ENODEV;
......@@ -1695,18 +1775,33 @@ EXPORT_SYMBOL_GPL(hid_destroy_device);
int __hid_register_driver(struct hid_driver *hdrv, struct module *owner,
const char *mod_name)
{
int ret;
hdrv->driver.name = hdrv->name;
hdrv->driver.bus = &hid_bus_type;
hdrv->driver.owner = owner;
hdrv->driver.mod_name = mod_name;
return driver_register(&hdrv->driver);
INIT_LIST_HEAD(&hdrv->dyn_list);
spin_lock_init(&hdrv->dyn_lock);
ret = driver_register(&hdrv->driver);
if (ret)
return ret;
ret = driver_create_file(&hdrv->driver, &driver_attr_new_id);
if (ret)
driver_unregister(&hdrv->driver);
return ret;
}
EXPORT_SYMBOL_GPL(__hid_register_driver);
void hid_unregister_driver(struct hid_driver *hdrv)
{
driver_remove_file(&hdrv->driver, &driver_attr_new_id);
driver_unregister(&hdrv->driver);
hid_free_dynids(hdrv);
}
EXPORT_SYMBOL_GPL(hid_unregister_driver);
......
......@@ -531,6 +531,8 @@ struct hid_usage_id {
* @name: driver name (e.g. "Footech_bar-wheel")
* @id_table: which devices is this driver for (must be non-NULL for probe
* to be called)
* @dyn_list: list of dynamically added device ids
* @dyn_lock: lock protecting @dyn_list
* @probe: new device inserted
* @remove: device removed (NULL if not a hot-plug capable driver)
* @report_table: on which reports to call raw_event (NULL means all)
......@@ -558,6 +560,9 @@ struct hid_driver {
char *name;
const struct hid_device_id *id_table;
struct list_head dyn_list;
spinlock_t dyn_lock;
int (*probe)(struct hid_device *dev, const struct hid_device_id *id);
void (*remove)(struct hid_device *dev);
......
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