Re: [PATCH v2] drm/dp_mst: Fix W=1 warnings

From: Jani Nikula
Date: Thu Nov 28 2019 - 08:34:34 EST


On Thu, 28 Nov 2019, Benjamin GAIGNARD <benjamin.gaignard@xxxxxx> wrote:
> On 11/28/19 12:21 PM, Jani Nikula wrote:
>> 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?
>
> Because this commit is not merged (yet ?) in drm-misc-next which where I
> start.

I mean just leave the hunk out and the problem will fix itself once the
stuff gets backmerged to drm-misc-next.

BR,
Jani.


>
> Benjamin
>
>> 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