HID: wiimote: Add write-register helpers

Add helpers to synchronously write registers of the wiimote. This is heavily
used by initialization functions for wiimote peripherals.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 27 insertions, 1 deletions

diff --git a/drivers/hid/hid-wiimote.c b/drivers/hid/hid-wiimote.c
index 0a5e458820b2..59a08933c73c 100644
--- a/drivers/hid/hid-wiimote.c
+++ b/drivers/hid/hid-wiimote.c
@@ -39,6 +39,9 @@ struct wiimote_state {
         struct completion ready;
         int cmd;
         __u32 opt;
+
+        /* results of synchronous requests */
+        __u8 cmd_err;
 };
 
 struct wiimote_data {
@@ -394,6 +397,25 @@ static void wiiproto_req_wmem(struct wiimote_data *wdata, bool eeprom,
         wiimote_queue(wdata, cmd, sizeof(cmd));
 }
 
+/* requries the cmd-mutex to be held */
+static int wiimote_cmd_write(struct wiimote_data *wdata, __u32 offset,
+                                                const __u8 *wmem, __u8 size)
+{
+        unsigned long flags;
+        int ret;
+
+        spin_lock_irqsave(&wdata->state.lock, flags);
+        wiimote_cmd_set(wdata, WIIPROTO_REQ_WMEM, 0);
+        wiiproto_req_wreg(wdata, offset, wmem, size);
+        spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+        ret = wiimote_cmd_wait(wdata);
+        if (!ret && wdata->state.cmd_err)
+                ret = -EIO;
+
+        return ret;
+}
+
 static enum led_brightness wiimote_leds_get(struct led_classdev *led_dev)
 {
         struct wiimote_data *wdata;
@@ -635,9 +657,13 @@ static void handler_return(struct wiimote_data *wdata, const __u8 *payload)
 
         handler_keys(wdata, payload);
 
-        if (err)
+        if (wiimote_cmd_pending(wdata, cmd, 0)) {
+                wdata->state.cmd_err = err;
+                wiimote_cmd_complete(wdata);
+        } else if (err) {
                 hid_warn(wdata->hdev, "Remote error %hhu on req %hhu\n", err,
                                                                         cmd);
+        }
 }
 
 static void handler_drm_KA(struct wiimote_data *wdata, const __u8 *payload)