Re: [PATCH] drm/dp_mst: Fix W=1 warnings
From: Jani Nikula
Date: Thu Nov 28 2019 - 05:03:42 EST
On Tue, 12 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.
>
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxx>
> ---
> drivers/gpu/drm/drm_dp_mst_topology.c | 50 +++++++++++++----------------------
> 1 file changed, 19 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
> index b854a422a523..6ff554be8000 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);
Someone who knows this code really needs to check if we should be using
crc4 instead of just throwing this away as unused.
> /* copy chunk into bigger msg */
> memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
> msg->curlen += msg->curchunk_len - 1;
> @@ -1744,14 +1741,13 @@ 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)
The function changed in c485e2c97dae ("drm/dp_mst: Refactor pdt
setup/teardown, add more locking").
> {
> - 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);
> @@ -1821,21 +1817,18 @@ 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(
> + drm_dp_send_dpcd_write(
> mstb->mgr,
> mstb->port_parent,
> DP_GUID,
> 16,
> mstb->guid);
Indentation could be fixed while at it.
> } else {
> -
> - ret = drm_dp_dpcd_write(
> + drm_dp_dpcd_write(
> mstb->mgr->aux,
> DP_GUID,
> mstb->guid,
> @@ -2427,14 +2420,14 @@ 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);
Maybe you should make the function void while at it?
>
> mstb->link_address_sent = true;
> drm_dp_queue_down_tx(mgr, txmsg);
> @@ -2476,7 +2469,6 @@ 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 +2476,7 @@ 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);
Maybe you should make the function void while at it?
> drm_dp_queue_down_tx(mgr, txmsg);
>
> @@ -2567,7 +2559,7 @@ 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 +2584,9 @@ 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);
Maybe you should make the function void while at it?
>
> drm_dp_queue_down_tx(mgr, txmsg);
>
> @@ -2623,7 +2615,7 @@ 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 +2628,7 @@ 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);
Maybe you should make the function void while at it?
> drm_dp_queue_down_tx(mgr, txmsg);
>
> ret = drm_dp_mst_wait_tx_reply(port->parent, txmsg);
> @@ -2856,7 +2848,6 @@ 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 +2862,7 @@ 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);
Maybe you should make the function void while at it?
> txmsg->dst = port->parent;
>
> drm_dp_queue_down_tx(mgr, txmsg);
> @@ -2909,7 +2900,6 @@ 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 +2914,7 @@ 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);
Maybe you should make the function void while at it?
> txmsg->dst = mstb;
>
> drm_dp_queue_down_tx(mgr, txmsg);
> @@ -3147,7 +3137,7 @@ 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 +3157,6 @@ 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 +3948,16 @@ 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