@@ -176,7 +176,7 @@ 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;
@@ -184,6 +184,8 @@ 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
@@ -192,25 +194,24 @@ 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(400, 500);
@@ -219,7 +220,11 @@ 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;
}
/**
@@ -408,9 +413,7 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
* before giving up the AUX transaction.
*/
for (retry = 0; retry < 7; retry++) {
- mutex_lock(&aux->hw_mutex);
err = aux->transfer(aux, msg);
- mutex_unlock(&aux->hw_mutex);
if (err < 0) {
if (err == -EBUSY)
continue;
@@ -492,6 +495,8 @@ 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;
msg.request = (msgs[i].flags & I2C_M_RD) ?
@@ -536,6 +541,8 @@ 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;
}