HID: make .raw_request mandatory

SET_REPORT and GET_REPORT are mandatory in the HID specification.
Make the corresponding API in hid-core mandatory too, which removes the
need to test against it in some various places.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

4 files changed, 12 insertions, 11 deletions

diff --git a/Documentation/hid/hid-transport.txt b/Documentation/hid/hid-transport.txt
index 9dbbceaef4f3..3dcba9fd4a3a 100644
--- a/Documentation/hid/hid-transport.txt
+++ b/Documentation/hid/hid-transport.txt
@@ -283,7 +283,8 @@ The available HID callbacks are:
                        int reqtype)
    Same as ->request() but provides the report as raw buffer. This request shall
    be synchronous. A transport driver must not use ->wait() to complete such
-   requests.
+   requests. This request is mandatory and hid core will reject the device if
+   it is missing.
 
  - int (*output_report) (struct hid_device *hdev, __u8 *buf, size_t len)
    Send raw output report via intr channel. Used by some HID device drivers
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index b6ae69711d2a..0b57babe3f9f 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1330,9 +1330,6 @@ void __hid_request(struct hid_device *hid, struct hid_report *report,
         int ret;
         int len;
 
-        if (!hid->ll_driver->raw_request)
-                return;
-
         buf = hid_alloc_report_buf(report, GFP_KERNEL);
         if (!buf)
                 return;
@@ -2472,6 +2469,14 @@ int hid_add_device(struct hid_device *hdev)
                 return -ENODEV;
 
         /*
+         * Check for the mandatory transport channel.
+         */
+         if (!hdev->ll_driver->raw_request) {
+                hid_err(hdev, "transport driver missing .raw_request()\n");
+                return -EINVAL;
+         }
+
+        /*
          * Read the device report descriptor once and use as template
          * for the driver-specific modifications.
          */
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 310b96779e8e..f5aef792f13b 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -1266,9 +1266,7 @@ static struct hid_input *hidinput_allocate(struct hid_device *hid)
         }
 
         input_set_drvdata(input_dev, hid);
-        if (hid->ll_driver->request || hid->ll_driver->output_report ||
-            hid->ll_driver->raw_request)
-                input_dev->event = hidinput_input_event;
+        input_dev->event = hidinput_input_event;
         input_dev->open = hidinput_open;
         input_dev->close = hidinput_close;
         input_dev->setkeycode = hidinput_setkeycode;
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 60f3ff762376..5eb282e0dff7 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -992,11 +992,8 @@ static inline int hid_hw_raw_request(struct hid_device *hdev,
         if (len < 1 || len > HID_MAX_BUFFER_SIZE || !buf)
                 return -EINVAL;
 
-        if (hdev->ll_driver->raw_request)
-                return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
+        return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
                                                     rtype, reqtype);
-
-        return -ENOSYS;
 }
 
 /**