Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / drivers / gpu / drm / drm_dp_helper.c

diff --git a/kernel/drivers/gpu/drm/drm_dp_helper.c b/kernel/drivers/gpu/drm/drm_dp_helper.c
index 9535c5b..7e5a972 100644 (file)
--- a/kernel/drivers/gpu/drm/drm_dp_helper.c
+++ b/kernel/drivers/gpu/drm/drm_dp_helper.c
@@ -178,7 +178,7 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
 {
        struct drm_dp_aux_msg msg;
        unsigned int retry;
-       int err;
+       int err = 0;
 
        memset(&msg, 0, sizeof(msg));
        msg.address = offset;
@@ -186,6 +186,8 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
        msg.buffer = buffer;
        msg.size = size;
 
+       mutex_lock(&aux->hw_mutex);
+
        /*
         * The specification doesn't give any recommendation on how often to
         * retry native transactions. We used to retry 7 times like for
@@ -194,25 +196,24 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
         */
        for (retry = 0; retry < 32; retry++) {
 
-               mutex_lock(&aux->hw_mutex);
                err = aux->transfer(aux, &msg);
-               mutex_unlock(&aux->hw_mutex);
                if (err < 0) {
                        if (err == -EBUSY)
                                continue;
 
-                       return err;
+                       goto unlock;
                }
 
 
                switch (msg.reply & DP_AUX_NATIVE_REPLY_MASK) {
                case DP_AUX_NATIVE_REPLY_ACK:
                        if (err < size)
-                               return -EPROTO;
-                       return err;
+                               err = -EPROTO;
+                       goto unlock;
 
                case DP_AUX_NATIVE_REPLY_NACK:
-                       return -EIO;
+                       err = -EIO;
+                       goto unlock;
 
                case DP_AUX_NATIVE_REPLY_DEFER:
                        usleep_range(AUX_RETRY_INTERVAL, AUX_RETRY_INTERVAL + 100);
@@ -221,7 +222,11 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
        }
 
        DRM_DEBUG_KMS("too many retries, giving up\n");
-       return -EIO;
+       err = -EIO;
+
+unlock:
+       mutex_unlock(&aux->hw_mutex);
+       return err;
 }
 
 /**
@@ -543,9 +548,7 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
        int max_retries = max(7, drm_dp_i2c_retry_count(msg, dp_aux_i2c_speed_khz));
 
        for (retry = 0, defer_i2c = 0; retry < (max_retries + defer_i2c); retry++) {
-               mutex_lock(&aux->hw_mutex);
                ret = aux->transfer(aux, msg);
-               mutex_unlock(&aux->hw_mutex);
                if (ret < 0) {
                        if (ret == -EBUSY)
                                continue;
@@ -684,6 +687,8 @@ static int drm_dp_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
 
        memset(&msg, 0, sizeof(msg));
 
+       mutex_lock(&aux->hw_mutex);
+
        for (i = 0; i < num; i++) {
                msg.address = msgs[i].addr;
                drm_dp_i2c_msg_set_request(&msg, &msgs[i]);
@@ -738,6 +743,8 @@ static int drm_dp_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
        msg.size = 0;
        (void)drm_dp_i2c_do_msg(aux, &msg);
 
+       mutex_unlock(&aux->hw_mutex);
+
        return err;
 }