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 <alan@signal11.us>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 2dcdf9f..5e0e4ee 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1159,6 +1159,32 @@
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 @@
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 @@
bus = "<UNKNOWN>";
}
+ 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 @@
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)