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From:   Benjamin Gaignard <benjamin.gaignard@st.com>
To:     <maarten.lankhorst@linux.intel.com>, <mripard@kernel.org>,
        <sean@poorly.run>, <airlied@linux.ie>, <daniel@ffwll.ch>
CC:     <dri-devel@lists.freedesktop.org>, <linux-kernel@vger.kernel.org>,
        Benjamin Gaignard <benjamin.gaignard@st.com>,
        Jani Nikula <jani.nikula@linux.intel.com>
Subject: [PATCH v3] drm/dp_mst: Fix W=1 warnings
Date:   Thu, 28 Nov 2019 14:50:57 +0100
Message-ID: <20191128135057.20020-1-benjamin.gaignard@st.com>
MIME-Version: 1.0
Content-Type: text/plain
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Fix the warnings that show up with W=1.
They are all about unused but set variables.
If functions returns are not used anymore make them void.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
CC: Jani Nikula <jani.nikula@linux.intel.com>

changes in version 3:
- remove the hunk that may conflict with c485e2c97dae 
  ("drm/dp_mst: Refactor pdt setup/teardown, add more locking")

changes in version 2:
- fix indentations
- when possible change functions prototype to void

drivers/gpu/drm/drm_dp_mst_topology.c | 83 +++++++++++++----------------------
 1 file changed, 31 insertions(+), 52 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 1437bc46368b..d5cb5688b5dd 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -674,7 +674,6 @@ static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
 				      u8 *replybuf, u8 replybuflen, bool hdr)
 {
 	int ret;
-	u8 crc4;
 
 	if (hdr) {
 		u8 hdrlen;
@@ -716,8 +715,6 @@ static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
 	}
 
 	if (msg->curchunk_idx >= msg->curchunk_len) {
-		/* do CRC */
-		crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
 		/* copy chunk into bigger msg */
 		memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
 		msg->curlen += msg->curchunk_len - 1;
@@ -1014,7 +1011,7 @@ static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
 	}
 }
 
-static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
+static void build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
 {
 	struct drm_dp_sideband_msg_req_body req;
 
@@ -1024,17 +1021,14 @@ static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32
 	req.u.dpcd_write.num_bytes = num_bytes;
 	req.u.dpcd_write.bytes = bytes;
 	drm_dp_encode_sideband_req(&req, msg);
-
-	return 0;
 }
 
-static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
+static void build_link_address(struct drm_dp_sideband_msg_tx *msg)
 {
 	struct drm_dp_sideband_msg_req_body req;
 
 	req.req_type = DP_LINK_ADDRESS;
 	drm_dp_encode_sideband_req(&req, msg);
-	return 0;
 }
 
 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
@@ -1048,7 +1042,7 @@ static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int por
 	return 0;
 }
 
-static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
+static void build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
 				  u8 vcpi, uint16_t pbn,
 				  u8 number_sdp_streams,
 				  u8 *sdp_stream_sink)
@@ -1064,10 +1058,9 @@ static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_n
 		   number_sdp_streams);
 	drm_dp_encode_sideband_req(&req, msg);
 	msg->path_msg = true;
-	return 0;
 }
 
-static int build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg,
+static void build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg,
 				  int port_num, bool power_up)
 {
 	struct drm_dp_sideband_msg_req_body req;
@@ -1080,7 +1073,6 @@ static int build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg,
 	req.u.port_num.port_number = port_num;
 	drm_dp_encode_sideband_req(&req, msg);
 	msg->path_msg = true;
-	return 0;
 }
 
 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
@@ -1746,14 +1738,13 @@ static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
  */
 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
 {
-	int ret;
 	u8 rad[6], lct;
 	bool send_link = false;
 	switch (port->pdt) {
 	case DP_PEER_DEVICE_DP_LEGACY_CONV:
 	case DP_PEER_DEVICE_SST_SINK:
 		/* add i2c over sideband */
-		ret = drm_dp_mst_register_i2c_bus(&port->aux);
+		drm_dp_mst_register_i2c_bus(&port->aux);
 		break;
 	case DP_PEER_DEVICE_MST_BRANCHING:
 		lct = drm_dp_calculate_rad(port, rad);
@@ -1823,25 +1814,20 @@ ssize_t drm_dp_mst_dpcd_write(struct drm_dp_aux *aux,
 
 static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid)
 {
-	int ret;
-
 	memcpy(mstb->guid, guid, 16);
 
 	if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) {
 		if (mstb->port_parent) {
-			ret = drm_dp_send_dpcd_write(
-					mstb->mgr,
-					mstb->port_parent,
-					DP_GUID,
-					16,
-					mstb->guid);
+			drm_dp_send_dpcd_write(mstb->mgr,
+					       mstb->port_parent,
+					       DP_GUID,
+					       16,
+					       mstb->guid);
 		} else {
-
-			ret = drm_dp_dpcd_write(
-					mstb->mgr->aux,
-					DP_GUID,
-					mstb->guid,
-					16);
+			drm_dp_dpcd_write(mstb->mgr->aux,
+					  DP_GUID,
+					  mstb->guid,
+					  16);
 		}
 	}
 }
@@ -2197,7 +2183,7 @@ static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
 	return false;
 }
 
-static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
+static void build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
 {
 	struct drm_dp_sideband_msg_req_body req;
 
@@ -2206,8 +2192,6 @@ static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32
 	req.u.dpcd_read.dpcd_address = offset;
 	req.u.dpcd_read.num_bytes = num_bytes;
 	drm_dp_encode_sideband_req(&req, msg);
-
-	return 0;
 }
 
 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
@@ -2429,14 +2413,14 @@ static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
 {
 	struct drm_dp_sideband_msg_tx *txmsg;
 	struct drm_dp_link_address_ack_reply *reply;
-	int i, len, ret;
+	int i, ret;
 
 	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
 	if (!txmsg)
 		return;
 
 	txmsg->dst = mstb;
-	len = build_link_address(txmsg);
+	build_link_address(txmsg);
 
 	mstb->link_address_sent = true;
 	drm_dp_queue_down_tx(mgr, txmsg);
@@ -2478,7 +2462,6 @@ drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
 {
 	struct drm_dp_enum_path_resources_ack_reply *path_res;
 	struct drm_dp_sideband_msg_tx *txmsg;
-	int len;
 	int ret;
 
 	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
@@ -2486,7 +2469,7 @@ drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
 		return -ENOMEM;
 
 	txmsg->dst = mstb;
-	len = build_enum_path_resources(txmsg, port->port_num);
+	build_enum_path_resources(txmsg, port->port_num);
 
 	drm_dp_queue_down_tx(mgr, txmsg);
 
@@ -2569,7 +2552,7 @@ static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
 {
 	struct drm_dp_sideband_msg_tx *txmsg;
 	struct drm_dp_mst_branch *mstb;
-	int len, ret, port_num;
+	int ret, port_num;
 	u8 sinks[DRM_DP_MAX_SDP_STREAMS];
 	int i;
 
@@ -2594,9 +2577,9 @@ static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
 		sinks[i] = i;
 
 	txmsg->dst = mstb;
-	len = build_allocate_payload(txmsg, port_num,
-				     id,
-				     pbn, port->num_sdp_streams, sinks);
+	build_allocate_payload(txmsg, port_num,
+			       id,
+			       pbn, port->num_sdp_streams, sinks);
 
 	drm_dp_queue_down_tx(mgr, txmsg);
 
@@ -2625,7 +2608,7 @@ int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr,
 				 struct drm_dp_mst_port *port, bool power_up)
 {
 	struct drm_dp_sideband_msg_tx *txmsg;
-	int len, ret;
+	int ret;
 
 	port = drm_dp_mst_topology_get_port_validated(mgr, port);
 	if (!port)
@@ -2638,7 +2621,7 @@ int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr,
 	}
 
 	txmsg->dst = port->parent;
-	len = build_power_updown_phy(txmsg, port->port_num, power_up);
+	build_power_updown_phy(txmsg, port->port_num, power_up);
 	drm_dp_queue_down_tx(mgr, txmsg);
 
 	ret = drm_dp_mst_wait_tx_reply(port->parent, txmsg);
@@ -2858,7 +2841,6 @@ static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
 				 struct drm_dp_mst_port *port,
 				 int offset, int size, u8 *bytes)
 {
-	int len;
 	int ret = 0;
 	struct drm_dp_sideband_msg_tx *txmsg;
 	struct drm_dp_mst_branch *mstb;
@@ -2873,7 +2855,7 @@ static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
 		goto fail_put;
 	}
 
-	len = build_dpcd_read(txmsg, port->port_num, offset, size);
+	build_dpcd_read(txmsg, port->port_num, offset, size);
 	txmsg->dst = port->parent;
 
 	drm_dp_queue_down_tx(mgr, txmsg);
@@ -2911,7 +2893,6 @@ static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
 				  struct drm_dp_mst_port *port,
 				  int offset, int size, u8 *bytes)
 {
-	int len;
 	int ret;
 	struct drm_dp_sideband_msg_tx *txmsg;
 	struct drm_dp_mst_branch *mstb;
@@ -2926,7 +2907,7 @@ static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
 		goto fail_put;
 	}
 
-	len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
+	build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
 	txmsg->dst = mstb;
 
 	drm_dp_queue_down_tx(mgr, txmsg);
@@ -3149,7 +3130,7 @@ static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
 {
 	int len;
 	u8 replyblock[32];
-	int replylen, origlen, curreply;
+	int replylen, curreply;
 	int ret;
 	struct drm_dp_sideband_msg_rx *msg;
 	int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
@@ -3169,7 +3150,6 @@ static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
 	}
 	replylen = msg->curchunk_len + msg->curchunk_hdrlen;
 
-	origlen = replylen;
 	replylen -= len;
 	curreply = len;
 	while (replylen > 0) {
@@ -3961,17 +3941,16 @@ void drm_dp_mst_dump_topology(struct seq_file *m,
 	mutex_lock(&mgr->lock);
 	if (mgr->mst_primary) {
 		u8 buf[DP_PAYLOAD_TABLE_SIZE];
-		int ret;
 
-		ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
+		drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
 		seq_printf(m, "dpcd: %*ph\n", DP_RECEIVER_CAP_SIZE, buf);
-		ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
+		drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
 		seq_printf(m, "faux/mst: %*ph\n", 2, buf);
-		ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
+		drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
 		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);
+		drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE);
 		seq_printf(m, "branch oui: %*phN devid: ", 3, buf);
 		for (i = 0x3; i < 0x8 && buf[i]; i++)
 			seq_printf(m, "%c", buf[i]);
-- 
2.15.0