Re: [PATCH v2] drm/dp_mst: Fix W=1 warnings
From: Jani Nikula
Date: Thu Nov 28 2019 - 06:21:47 EST
On Thu, 28 Nov 2019, Benjamin Gaignard <benjamin.gaignard@xxxxxx> wrote:
> 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@xxxxxx>
> CC: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
> ---
> changes in version 2:
> - fix indentations
> - when possible change functions prototype to void
>
> Note: this patch may conflict with c485e2c97dae ("drm/dp_mst: Refactor pdt
> setup/teardown, add more locking") when it will hit drm-misc-next
Well, why create an unnecessary conflict when the referenced commit also
fixes the same warnings as a side-effect?
BR,
Jani.
>
> 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 b854a422a523..ff2d81db0778 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -672,7 +672,6 @@ 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;
> @@ -714,8 +713,6 @@ 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;
> @@ -1012,7 +1009,7 @@ 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;
>
> @@ -1022,17 +1019,14 @@ 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)
> @@ -1046,7 +1040,7 @@ 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)
> @@ -1062,10 +1056,9 @@ 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;
> @@ -1078,7 +1071,6 @@ 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,
> @@ -1744,14 +1736,13 @@ 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);
> @@ -1821,25 +1812,20 @@ 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);
> }
> }
> }
> @@ -2195,7 +2181,7 @@ 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;
>
> @@ -2204,8 +2190,6 @@ 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,
> @@ -2427,14 +2411,14 @@ 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);
> @@ -2476,7 +2460,6 @@ 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);
> @@ -2484,7 +2467,7 @@ 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);
>
> @@ -2567,7 +2550,7 @@ 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;
>
> @@ -2592,9 +2575,9 @@ 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);
>
> @@ -2623,7 +2606,7 @@ 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)
> @@ -2636,7 +2619,7 @@ 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);
> @@ -2856,7 +2839,6 @@ 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;
> @@ -2871,7 +2853,7 @@ 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);
> @@ -2909,7 +2891,6 @@ 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;
> @@ -2924,7 +2905,7 @@ 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);
> @@ -3147,7 +3128,7 @@ 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;
> @@ -3167,7 +3148,6 @@ 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) {
> @@ -3959,17 +3939,16 @@ 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]);
--
Jani Nikula, Intel Open Source Graphics Center