From 4d53b8012f1f01ddb3f24db2031b042bb4cbd0d0 Mon Sep 17 00:00:00 2001 From: Henrik Rydberg Date: Mon, 23 Apr 2012 12:07:02 +0200 Subject: [PATCH] HID: Add device group to modalias HID devices are only partially presented to userland. Hotplugged devices emit events containing a modalias based on the basic bus, vendor and product entities. However, in practise a hid device can depend on details such as a single usb interface or a particular item in a report descriptor. This patch adds a device group to the hid device id, and broadcasts it using uevent and the device modalias. The module alias generation is modified to match. As a consequence, a device with a non-zero group will be processed by the corresponding group driver instead of by the generic hid driver. Signed-off-by: Henrik Rydberg Acked-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-core.c | 24 ++++++++++++++++++++++-- include/linux/hid.h | 1 + include/linux/mod_devicetable.h | 3 ++- scripts/mod/file2alias.c | 2 ++ 4 files changed, 27 insertions(+), 3 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 9ed4ff37dc2b..cfcb69eb17d6 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1222,6 +1222,7 @@ static bool hid_match_one_id(struct hid_device *hdev, const struct hid_device_id *id) { return id->bus == hdev->bus && + (id->group == HID_GROUP_ANY || id->group == hdev->group) && (id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) && (id->product == HID_ANY_ID || id->product == hdev->product); } @@ -1694,6 +1695,7 @@ static ssize_t store_new_id(struct device_driver *drv, const char *buf, return -ENOMEM; dynid->id.bus = bus; + dynid->id.group = HID_GROUP_ANY; dynid->id.vendor = vendor; dynid->id.product = product; dynid->id.driver_data = driver_data; @@ -1817,6 +1819,23 @@ static int hid_device_remove(struct device *dev) return 0; } +static ssize_t modalias_show(struct device *dev, struct device_attribute *a, + char *buf) +{ + struct hid_device *hdev = container_of(dev, struct hid_device, dev); + int len; + + len = snprintf(buf, PAGE_SIZE, "hid:b%04Xg%04Xv%08Xp%08X\n", + hdev->bus, hdev->group, hdev->vendor, hdev->product); + + return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; +} + +static struct device_attribute hid_dev_attrs[] = { + __ATTR_RO(modalias), + __ATTR_NULL, +}; + static int hid_uevent(struct device *dev, struct kobj_uevent_env *env) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); @@ -1834,8 +1853,8 @@ static int hid_uevent(struct device *dev, struct kobj_uevent_env *env) if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq)) return -ENOMEM; - if (add_uevent_var(env, "MODALIAS=hid:b%04Xv%08Xp%08X", - hdev->bus, hdev->vendor, hdev->product)) + if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X", + hdev->bus, hdev->group, hdev->vendor, hdev->product)) return -ENOMEM; return 0; @@ -1843,6 +1862,7 @@ static int hid_uevent(struct device *dev, struct kobj_uevent_env *env) static struct bus_type hid_bus_type = { .name = "hid", + .dev_attrs = hid_dev_attrs, .match = hid_bus_match, .probe = hid_device_probe, .remove = hid_device_remove, diff --git a/include/linux/hid.h b/include/linux/hid.h index d8e7cc7f894f..a0e27ddb887d 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -476,6 +476,7 @@ struct hid_device { /* device report descriptor */ unsigned maxcollection; /* Number of parsed collections */ unsigned maxapplication; /* Number of applications */ __u16 bus; /* BUS ID */ + __u16 group; /* Report group */ __u32 vendor; /* Vendor ID */ __u32 product; /* Product ID */ __u32 version; /* HID version */ diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index 501da4cb8a6d..55ed0b0dc610 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -132,10 +132,11 @@ struct usb_device_id { #define USB_DEVICE_ID_MATCH_INT_PROTOCOL 0x0200 #define HID_ANY_ID (~0) +#define HID_GROUP_ANY 0x0000 struct hid_device_id { __u16 bus; - __u16 pad1; + __u16 group; __u32 vendor; __u32 product; kernel_ulong_t driver_data diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 8e730ccc3f2b..fe967cee7371 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -336,10 +336,12 @@ static int do_hid_entry(const char *filename, struct hid_device_id *id, char *alias) { id->bus = TO_NATIVE(id->bus); + id->group = TO_NATIVE(id->group); id->vendor = TO_NATIVE(id->vendor); id->product = TO_NATIVE(id->product); sprintf(alias, "hid:b%04X", id->bus); + ADD(alias, "g", id->group != HID_GROUP_ANY, id->group); ADD(alias, "v", id->vendor != HID_ANY_ID, id->vendor); ADD(alias, "p", id->product != HID_ANY_ID, id->product); -- GitLab