HID: uhid: reintroduce uhid_hid_get_raw()

This reverts commit 4a76d370f0c0508b5d6580d15eae3d40b47d837c. Removing
it was a mistake, as we need a means to access GET_REPORT.

Reported-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c
index 49fbe97..b6de903 100644 (file)
--- a/drivers/hid/uhid.c
+++ b/drivers/hid/uhid.c
@@ -123,6 +123,89 @@ static int uhid_hid_parse(struct hid_device *hid)
        return hid_parse_report(hid, uhid->rd_data, uhid->rd_size);
 }
 
+static int uhid_hid_get_raw(struct hid_device *hid, unsigned char rnum,
+                           __u8 *buf, size_t count, unsigned char rtype)
+{
+       struct uhid_device *uhid = hid->driver_data;
+       __u8 report_type;
+       struct uhid_event *ev;
+       unsigned long flags;
+       int ret;
+       size_t uninitialized_var(len);
+       struct uhid_feature_answer_req *req;
+
+       if (!uhid->running)
+               return -EIO;
+
+       switch (rtype) {
+       case HID_FEATURE_REPORT:
+               report_type = UHID_FEATURE_REPORT;
+               break;
+       case HID_OUTPUT_REPORT:
+               report_type = UHID_OUTPUT_REPORT;
+               break;
+       case HID_INPUT_REPORT:
+               report_type = UHID_INPUT_REPORT;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       ret = mutex_lock_interruptible(&uhid->report_lock);
+       if (ret)
+               return ret;
+
+       ev = kzalloc(sizeof(*ev), GFP_KERNEL);
+       if (!ev) {
+               ret = -ENOMEM;
+               goto unlock;
+       }
+
+       spin_lock_irqsave(&uhid->qlock, flags);
+       ev->type = UHID_FEATURE;
+       ev->u.feature.id = atomic_inc_return(&uhid->report_id);
+       ev->u.feature.rnum = rnum;
+       ev->u.feature.rtype = report_type;
+
+       atomic_set(&uhid->report_done, 0);
+       uhid_queue(uhid, ev);
+       spin_unlock_irqrestore(&uhid->qlock, flags);
+
+       ret = wait_event_interruptible_timeout(uhid->report_wait,
+                               atomic_read(&uhid->report_done), 5 * HZ);
+
+       /*
+        * Make sure "uhid->running" is cleared on shutdown before
+        * "uhid->report_done" is set.
+        */
+       smp_rmb();
+       if (!ret || !uhid->running) {
+               ret = -EIO;
+       } else if (ret < 0) {
+               ret = -ERESTARTSYS;
+       } else {
+               spin_lock_irqsave(&uhid->qlock, flags);
+               req = &uhid->report_buf.u.feature_answer;
+
+               if (req->err) {
+                       ret = -EIO;
+               } else {
+                       ret = 0;
+                       len = min(count,
+                               min_t(size_t, req->size, UHID_DATA_MAX));
+                       memcpy(buf, req->data, len);
+               }
+
+               spin_unlock_irqrestore(&uhid->qlock, flags);
+       }
+
+       atomic_set(&uhid->report_done, 1);
+
+unlock:
+       mutex_unlock(&uhid->report_lock);
+       return ret ? ret : len;
+}
+
 static int uhid_hid_output_raw(struct hid_device *hid, __u8 *buf, size_t count,
                               unsigned char report_type)
 {