HID: thingm: improve locking

[deliverable/linux.git] / drivers / hid / hid-thingm.c

diff --git a/drivers/hid/hid-thingm.c b/drivers/hid/hid-thingm.c
index 5e35ec1b6d8a3d2bf0834b308805f9ad6469b98d..f4196ac25a649c7287470f7b581d82e1101faa7c 100644 (file)
--- a/drivers/hid/hid-thingm.c
+++ b/drivers/hid/hid-thingm.c
@@ -77,9 +77,13 @@ static int thingm_send(struct thingm_device *tdev, u8 buf[REPORT_SIZE])
                        buf[0], buf[1], buf[2], buf[3], buf[4],
                        buf[5], buf[6], buf[7], buf[8]);
 
+       mutex_lock(&tdev->lock);
+
        ret = hid_hw_raw_request(tdev->hdev, buf[0], buf, REPORT_SIZE,
                        HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
 
+       mutex_unlock(&tdev->lock);
+
        return ret < 0 ? ret : 0;
 }
 
@@ -87,16 +91,31 @@ static int thingm_recv(struct thingm_device *tdev, u8 buf[REPORT_SIZE])
 {
        int ret;
 
+       /*
+        * A read consists of two operations: sending the read command
+        * and the actual read from the device. Use the mutex to protect
+        * the full sequence of both operations.
+        */
+       mutex_lock(&tdev->lock);
+
+       ret = hid_hw_raw_request(tdev->hdev, buf[0], buf, REPORT_SIZE,
+                       HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+       if (ret < 0)
+               goto err;
+
        ret = hid_hw_raw_request(tdev->hdev, buf[0], buf, REPORT_SIZE,
                        HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
        if (ret < 0)
-               return ret;
+               goto err;
+
+       ret = 0;
 
        hid_dbg(tdev->hdev, "<- %d %c %02hhx %02hhx %02hhx %02hhx %02hhx %02hhx %02hhx\n",
                        buf[0], buf[1], buf[2], buf[3], buf[4],
                        buf[5], buf[6], buf[7], buf[8]);
-
-       return 0;
+err:
+       mutex_unlock(&tdev->lock);
+       return ret;
 }
 
 static int thingm_version(struct thingm_device *tdev)
@@ -104,10 +123,6 @@ static int thingm_version(struct thingm_device *tdev)
        u8 buf[REPORT_SIZE] = { REPORT_ID, 'v', 0, 0, 0, 0, 0, 0, 0 };
        int err;
 
-       err = thingm_send(tdev, buf);
-       if (err)
-               return err;
-
        err = thingm_recv(tdev, buf);
        if (err)
                return err;
@@ -135,14 +150,10 @@ static int thingm_led_set(struct led_classdev *ldev,
        struct thingm_led *led = container_of(ldev, struct thingm_led, ldev);
        int ret;
 
-       mutex_lock(&led->rgb->tdev->lock);
-
        ret = thingm_write_color(led->rgb);
        if (ret)
                hid_err(led->rgb->tdev->hdev, "failed to write color\n");
 
-       mutex_unlock(&led->rgb->tdev->lock);
-
        return ret;
 }