From e04a0442d33b8cf183bba38646447b891bb02123 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Mon, 20 Nov 2017 11:48:44 +0100 Subject: HID: core: remove the absolute need of hid_have_special_driver[] Most HID devices behave properly when they are used with hid-generic. Since kernel v4.12, we do not poll for input reports at plug in, so hid-generic should behave properly with all HID devices. There has been a long standing list of HID devices that have a special driver. It used to be just a few, but with time, this list went too big, and we can not ask users to know which HID special driver will pick up their device. We can teach hid-generic to be nice with others. If a device is not explicitly marked with HID_QUIRK_HAVE_SPECIAL_DRIVER, we can allow hid-generic to pick up the device as long as no other loaded HID driver will match the device. When the special driver appears, hid-generic can step back and let the special driver handling the device. In case this special driver is removed, this good old pal of hid-generic will rebind to the device. This basically makes the list hid_have_special_driver[] useless. It still allows to not see a hid-generic driver bound and removed during boot, so we can keep it around. This will also help other people to have a special HID driver without the need of recompiling hid-core. Signed-off-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-core.c | 76 +++++++++++++++++++++++++++++++------------------- 1 file changed, 48 insertions(+), 28 deletions(-) (limited to 'drivers/hid/hid-core.c') diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index e6d586a22bbd..7297b1d1300c 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -830,31 +830,6 @@ static int hid_scan_report(struct hid_device *hid) break; } - /* fall back to generic driver in case specific driver doesn't exist */ - switch (hid->group) { - case HID_GROUP_MULTITOUCH_WIN_8: - /* fall-through */ - case HID_GROUP_MULTITOUCH: - if (!IS_ENABLED(CONFIG_HID_MULTITOUCH)) - hid->group = HID_GROUP_GENERIC; - break; - case HID_GROUP_SENSOR_HUB: - if (!IS_ENABLED(CONFIG_HID_SENSOR_HUB)) - hid->group = HID_GROUP_GENERIC; - break; - case HID_GROUP_RMI: - if (!IS_ENABLED(CONFIG_HID_RMI)) - hid->group = HID_GROUP_GENERIC; - break; - case HID_GROUP_WACOM: - if (!IS_ENABLED(CONFIG_HID_WACOM)) - hid->group = HID_GROUP_GENERIC; - break; - case HID_GROUP_LOGITECH_DJ_DEVICE: - if (!IS_ENABLED(CONFIG_HID_LOGITECH_DJ)) - hid->group = HID_GROUP_GENERIC; - break; - } vfree(parser); return 0; } @@ -1928,8 +1903,8 @@ static void hid_free_dynids(struct hid_driver *hdrv) spin_unlock(&hdrv->dyn_lock); } -static const struct hid_device_id *hid_match_device(struct hid_device *hdev, - struct hid_driver *hdrv) +const struct hid_device_id *hid_match_device(struct hid_device *hdev, + struct hid_driver *hdrv) { struct hid_dynid *dynid; @@ -1944,6 +1919,7 @@ static const struct hid_device_id *hid_match_device(struct hid_device *hdev, return hid_match_id(hdev, hdrv->id_table); } +EXPORT_SYMBOL_GPL(hid_match_device); static int hid_bus_match(struct device *dev, struct device_driver *drv) { @@ -1973,6 +1949,23 @@ static int hid_device_probe(struct device *dev) goto unlock; } + if (hdrv->match) { + if (!hdrv->match(hdev, hid_ignore_special_drivers)) { + ret = -ENODEV; + goto unlock; + } + } else { + /* + * hid-generic implements .match(), so if + * hid_ignore_special_drivers is set, we can safely + * return. + */ + if (hid_ignore_special_drivers) { + ret = -ENODEV; + goto unlock; + } + } + hdev->driver = hdrv; if (hdrv->probe) { ret = hdrv->probe(hdev, id); @@ -2069,7 +2062,7 @@ static int hid_uevent(struct device *dev, struct kobj_uevent_env *env) return 0; } -static struct bus_type hid_bus_type = { +struct bus_type hid_bus_type = { .name = "hid", .dev_groups = hid_dev_groups, .drv_groups = hid_drv_groups, @@ -2203,6 +2196,29 @@ void hid_destroy_device(struct hid_device *hdev) } EXPORT_SYMBOL_GPL(hid_destroy_device); + +static int __bus_add_driver(struct device_driver *drv, void *data) +{ + struct hid_driver *added_hdrv = data; + struct hid_driver *hdrv = to_hid_driver(drv); + + if (hdrv->bus_add_driver) + hdrv->bus_add_driver(added_hdrv); + + return 0; +} + +static int __bus_removed_driver(struct device_driver *drv, void *data) +{ + struct hid_driver *removed_hdrv = data; + struct hid_driver *hdrv = to_hid_driver(drv); + + if (hdrv->bus_removed_driver) + hdrv->bus_removed_driver(removed_hdrv); + + return 0; +} + int __hid_register_driver(struct hid_driver *hdrv, struct module *owner, const char *mod_name) { @@ -2214,6 +2230,8 @@ int __hid_register_driver(struct hid_driver *hdrv, struct module *owner, INIT_LIST_HEAD(&hdrv->dyn_list); spin_lock_init(&hdrv->dyn_lock); + bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_add_driver); + return driver_register(&hdrv->driver); } EXPORT_SYMBOL_GPL(__hid_register_driver); @@ -2222,6 +2240,8 @@ void hid_unregister_driver(struct hid_driver *hdrv) { driver_unregister(&hdrv->driver); hid_free_dynids(hdrv); + + bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver); } EXPORT_SYMBOL_GPL(hid_unregister_driver); -- cgit v1.2.3