From 6d3bfb74341c2c1454fcf5ec9c4dd707011f78e5 Mon Sep 17 00:00:00 2001 From: Alan Ott Date: Sun, 23 Jan 2011 22:50:18 -0500 Subject: [PATCH] HID: Add HID Report Descriptor to sysfs Add a new binary sysfs entry called report_descriptor which contains the HID report descriptor. Signed-off-by: Alan Ott Signed-off-by: Jiri Kosina --- Documentation/ABI/testing/sysfs-driver-hid | 10 +++++++ drivers/hid/hid-core.c | 33 ++++++++++++++++++++++ 2 files changed, 43 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-driver-hid diff --git a/Documentation/ABI/testing/sysfs-driver-hid b/Documentation/ABI/testing/sysfs-driver-hid new file mode 100644 index 00000000000..b6490e14fe8 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-hid @@ -0,0 +1,10 @@ +What: For USB devices : /sys/bus/usb/devices/-:./::./report_descriptor + For BT devices : /sys/class/bluetooth/hci/::./report_descriptor + Symlink : /sys/class/hidraw/hidraw/device/report_descriptor +Date: Jan 2011 +KernelVersion: 2.0.39 +Contact: Alan Ott +Description: When read, this file returns the device's raw binary HID + report descriptor. + This file cannot be written. +Users: HIDAPI library (http://www.signal11.us/oss/hidapi) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 2dcdf9ff02e..5e0e4eea706 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1159,6 +1159,32 @@ static bool hid_hiddev(struct hid_device *hdev) return !!hid_match_id(hdev, hid_hiddev_list); } + +static ssize_t +read_report_descriptor(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t off, size_t count) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct hid_device *hdev = container_of(dev, struct hid_device, dev); + + if (off >= hdev->rsize) + return 0; + + if (off + count > hdev->rsize) + count = hdev->rsize - off; + + memcpy(buf, hdev->rdesc + off, count); + + return count; +} + +static struct bin_attribute dev_bin_attr_report_desc = { + .attr = { .name = "report_descriptor", .mode = 0444 }, + .read = read_report_descriptor, + .size = HID_MAX_DESCRIPTOR_SIZE, +}; + int hid_connect(struct hid_device *hdev, unsigned int connect_mask) { static const char *types[] = { "Device", "Pointer", "Mouse", "Device", @@ -1169,6 +1195,7 @@ int hid_connect(struct hid_device *hdev, unsigned int connect_mask) char buf[64]; unsigned int i; int len; + int ret; if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE) connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV); @@ -1230,6 +1257,11 @@ int hid_connect(struct hid_device *hdev, unsigned int connect_mask) bus = ""; } + ret = device_create_bin_file(&hdev->dev, &dev_bin_attr_report_desc); + if (ret) + hid_warn(hdev, + "can't create sysfs report descriptor attribute err: %d\n", ret); + hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n", buf, bus, hdev->version >> 8, hdev->version & 0xff, type, hdev->name, hdev->phys); @@ -1240,6 +1272,7 @@ EXPORT_SYMBOL_GPL(hid_connect); void hid_disconnect(struct hid_device *hdev) { + device_remove_bin_file(&hdev->dev, &dev_bin_attr_report_desc); if (hdev->claimed & HID_CLAIMED_INPUT) hidinput_disconnect(hdev); if (hdev->claimed & HID_CLAIMED_HIDDEV)