diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/hid/usbhid/hid-core.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c index c1a1dd54601c..aa1c503a9526 100644 --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -28,6 +28,7 @@ #include <linux/input.h> #include <linux/wait.h> #include <linux/workqueue.h> +#include <linux/string.h> #include <linux/usb.h> @@ -1364,7 +1365,34 @@ static int hid_post_reset(struct usb_interface *intf) struct usb_device *dev = interface_to_usbdev (intf); struct hid_device *hid = usb_get_intfdata(intf); struct usbhid_device *usbhid = hid->driver_data; + struct usb_host_interface *interface = intf->cur_altsetting; int status; + char *rdesc; + + /* Fetch and examine the HID report descriptor. If this + * has changed, then rebind. Since usbcore's check of the + * configuration descriptors passed, we already know that + * the size of the HID report descriptor has not changed. + */ + rdesc = kmalloc(hid->rsize, GFP_KERNEL); + if (!rdesc) { + dbg_hid("couldn't allocate rdesc memory (post_reset)\n"); + return 1; + } + status = hid_get_class_descriptor(dev, + interface->desc.bInterfaceNumber, + HID_DT_REPORT, rdesc, hid->rsize); + if (status < 0) { + dbg_hid("reading report descriptor failed (post_reset)\n"); + kfree(rdesc); + return 1; + } + status = memcmp(rdesc, hid->rdesc, hid->rsize); + kfree(rdesc); + if (status != 0) { + dbg_hid("report descriptor changed\n"); + return 1; + } spin_lock_irq(&usbhid->lock); clear_bit(HID_RESET_PENDING, &usbhid->iofl); |