[PATCH RESEND RFC v4 5/6] drm/display: dp-mst-topology: use new DCPD access helpers

[Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>]

From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Switch drm_dp_mst_topology.c to use new set of DPCD read / write helpers.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/display/drm_dp_mst_topology.c | 105 +++++++++++++-------------
 1 file changed, 51 insertions(+), 54 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index 3a1f1ffc7b5528b940485e7d96b1913bd85b0153..de3fc6090c906efce3dbaa8462d736ebf9094b34 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -2201,15 +2201,12 @@ static int drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, guid_t *guid)
 						     mstb->port_parent,
 						     DP_GUID, sizeof(buf), buf);
 		} else {
-			ret = drm_dp_dpcd_write(mstb->mgr->aux,
-						DP_GUID, buf, sizeof(buf));
+			ret = drm_dp_dpcd_write_data(mstb->mgr->aux,
+						     DP_GUID, buf, sizeof(buf));
 		}
 	}
 
-	if (ret < 16 && ret > 0)
-		return -EPROTO;
-
-	return ret == 16 ? 0 : ret;
+	return ret;
 }
 
 static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
@@ -2744,14 +2741,13 @@ static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
 	do {
 		tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
 
-		ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
-					&msg[offset],
-					tosend);
-		if (ret != tosend) {
-			if (ret == -EIO && retries < 5) {
-				retries++;
-				goto retry;
-			}
+		ret = drm_dp_dpcd_write_data(mgr->aux, regbase + offset,
+					     &msg[offset],
+					     tosend);
+		if (ret == -EIO && retries < 5) {
+			retries++;
+			goto retry;
+		} else if (ret < 0) {
 			drm_dbg_kms(mgr->dev, "failed to dpcd write %d %d\n", tosend, ret);
 
 			return -EIO;
@@ -3624,7 +3620,7 @@ enum drm_dp_mst_mode drm_dp_read_mst_cap(struct drm_dp_aux *aux,
 	if (dpcd[DP_DPCD_REV] < DP_DPCD_REV_12)
 		return DRM_DP_SST;
 
-	if (drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &mstm_cap) != 1)
+	if (drm_dp_dpcd_read_byte(aux, DP_MSTM_CAP, &mstm_cap) < 0)
 		return DRM_DP_SST;
 
 	if (mstm_cap & DP_MST_CAP)
@@ -3679,10 +3675,10 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
 		mgr->mst_primary = mstb;
 		drm_dp_mst_topology_get_mstb(mgr->mst_primary);
 
-		ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
-					 DP_MST_EN |
-					 DP_UP_REQ_EN |
-					 DP_UPSTREAM_IS_SRC);
+		ret = drm_dp_dpcd_write_byte(mgr->aux, DP_MSTM_CTRL,
+					     DP_MST_EN |
+					     DP_UP_REQ_EN |
+					     DP_UPSTREAM_IS_SRC);
 		if (ret < 0)
 			goto out_unlock;
 
@@ -3697,7 +3693,7 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
 		mstb = mgr->mst_primary;
 		mgr->mst_primary = NULL;
 		/* this can fail if the device is gone */
-		drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
+		drm_dp_dpcd_write_byte(mgr->aux, DP_MSTM_CTRL, 0);
 		ret = 0;
 		mgr->payload_id_table_cleared = false;
 
@@ -3763,8 +3759,8 @@ EXPORT_SYMBOL(drm_dp_mst_topology_queue_probe);
 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
 {
 	mutex_lock(&mgr->lock);
-	drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
-			   DP_MST_EN | DP_UPSTREAM_IS_SRC);
+	drm_dp_dpcd_write_byte(mgr->aux, DP_MSTM_CTRL,
+			       DP_MST_EN | DP_UPSTREAM_IS_SRC);
 	mutex_unlock(&mgr->lock);
 	flush_work(&mgr->up_req_work);
 	flush_work(&mgr->work);
@@ -3813,18 +3809,18 @@ int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr,
 		goto out_fail;
 	}
 
-	ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
-				 DP_MST_EN |
-				 DP_UP_REQ_EN |
-				 DP_UPSTREAM_IS_SRC);
+	ret = drm_dp_dpcd_write_byte(mgr->aux, DP_MSTM_CTRL,
+				     DP_MST_EN |
+				     DP_UP_REQ_EN |
+				     DP_UPSTREAM_IS_SRC);
 	if (ret < 0) {
 		drm_dbg_kms(mgr->dev, "mst write failed - undocked during suspend?\n");
 		goto out_fail;
 	}
 
 	/* Some hubs forget their guids after they resume */
-	ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, buf, sizeof(buf));
-	if (ret != sizeof(buf)) {
+	ret = drm_dp_dpcd_read_data(mgr->aux, DP_GUID, buf, sizeof(buf));
+	if (ret < 0) {
 		drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n");
 		goto out_fail;
 	}
@@ -3883,8 +3879,8 @@ drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
 		*mstb = NULL;
 
 	len = min(mgr->max_dpcd_transaction_bytes, 16);
-	ret = drm_dp_dpcd_read(mgr->aux, basereg, replyblock, len);
-	if (ret != len) {
+	ret = drm_dp_dpcd_read_data(mgr->aux, basereg, replyblock, len);
+	if (ret < 0) {
 		drm_dbg_kms(mgr->dev, "failed to read DPCD down rep %d %d\n", len, ret);
 		return false;
 	}
@@ -3922,9 +3918,9 @@ drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
 	curreply = len;
 	while (replylen > 0) {
 		len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
-		ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
-				    replyblock, len);
-		if (ret != len) {
+		ret = drm_dp_dpcd_read_data(mgr->aux, basereg + curreply,
+					    replyblock, len);
+		if (ret < 0) {
 			drm_dbg_kms(mgr->dev, "failed to read a chunk (len %d, ret %d)\n",
 				    len, ret);
 			return false;
@@ -4881,9 +4877,9 @@ static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
 	int i;
 
 	for (i = 0; i < DP_PAYLOAD_TABLE_SIZE; i += 16) {
-		if (drm_dp_dpcd_read(mgr->aux,
-				     DP_PAYLOAD_TABLE_UPDATE_STATUS + i,
-				     &buf[i], 16) != 16)
+		if (drm_dp_dpcd_read_data(mgr->aux,
+					  DP_PAYLOAD_TABLE_UPDATE_STATUS + i,
+					  &buf[i], 16) < 0)
 			return false;
 	}
 	return true;
@@ -4972,23 +4968,24 @@ void drm_dp_mst_dump_topology(struct seq_file *m,
 		}
 		seq_printf(m, "dpcd: %*ph\n", DP_RECEIVER_CAP_SIZE, buf);
 
-		ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
-		if (ret != 2) {
+		ret = drm_dp_dpcd_read_data(mgr->aux, DP_FAUX_CAP, buf, 2);
+		if (ret < 0) {
 			seq_printf(m, "faux/mst read failed\n");
 			goto out;
 		}
 		seq_printf(m, "faux/mst: %*ph\n", 2, buf);
 
-		ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
-		if (ret != 1) {
+		ret = drm_dp_dpcd_read_data(mgr->aux, DP_MSTM_CTRL, buf, 1);
+		if (ret < 0) {
 			seq_printf(m, "mst ctrl read failed\n");
 			goto out;
 		}
 		seq_printf(m, "mst ctrl: %*ph\n", 1, buf);
 
 		/* dump the standard OUI branch header */
-		ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE);
-		if (ret != DP_BRANCH_OUI_HEADER_SIZE) {
+		ret = drm_dp_dpcd_read_data(mgr->aux, DP_BRANCH_OUI, buf,
+					    DP_BRANCH_OUI_HEADER_SIZE);
+		if (ret < 0) {
 			seq_printf(m, "branch oui read failed\n");
 			goto out;
 		}
@@ -6112,14 +6109,14 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port)
 
 	/* DP-to-DP peer device */
 	if (drm_dp_mst_is_virtual_dpcd(immediate_upstream_port)) {
-		if (drm_dp_dpcd_read(&port->aux,
-				     DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1)
+		if (drm_dp_dpcd_read_data(&port->aux,
+					  DP_DSC_SUPPORT, &endpoint_dsc, 1) < 0)
 			return NULL;
-		if (drm_dp_dpcd_read(&port->aux,
-				     DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1)
+		if (drm_dp_dpcd_read_data(&port->aux,
+					  DP_FEC_CAPABILITY, &endpoint_fec, 1) < 0)
 			return NULL;
-		if (drm_dp_dpcd_read(&immediate_upstream_port->aux,
-				     DP_DSC_SUPPORT, &upstream_dsc, 1) != 1)
+		if (drm_dp_dpcd_read_data(&immediate_upstream_port->aux,
+					  DP_DSC_SUPPORT, &upstream_dsc, 1) < 0)
 			return NULL;
 
 		/* Enpoint decompression with DP-to-DP peer device */
@@ -6157,8 +6154,8 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port)
 	if (drm_dp_has_quirk(&desc, DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD)) {
 		u8 dpcd_ext[DP_RECEIVER_CAP_SIZE];
 
-		if (drm_dp_dpcd_read(immediate_upstream_aux,
-				     DP_DSC_SUPPORT, &upstream_dsc, 1) != 1)
+		if (drm_dp_dpcd_read_data(immediate_upstream_aux,
+					  DP_DSC_SUPPORT, &upstream_dsc, 1) < 0)
 			return NULL;
 
 		if (!(upstream_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED))
@@ -6180,11 +6177,11 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port)
 	 * therefore the endpoint needs to be
 	 * both DSC and FEC capable.
 	 */
-	if (drm_dp_dpcd_read(&port->aux,
-	   DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1)
+	if (drm_dp_dpcd_read_data(&port->aux,
+				  DP_DSC_SUPPORT, &endpoint_dsc, 1) < 0)
 		return NULL;
-	if (drm_dp_dpcd_read(&port->aux,
-	   DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1)
+	if (drm_dp_dpcd_read_data(&port->aux,
+				  DP_FEC_CAPABILITY, &endpoint_fec, 1) < 0)
 		return NULL;
 	if ((endpoint_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED) &&
 	   (endpoint_fec & DP_FEC_CAPABLE))

-- 
2.39.5