Re: [PATCH v3] drm/dp_mst: Fix W=1 warnings

Le ven. 24 janv. 2020 à 23:08, Lyude Paul lyude@redhat.com a écrit :

On Tue, 2020-01-07 at 14:11 +0100, Benjamin Gaignard wrote:

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Le ven. 20 déc. 2019 à 15:03, Benjamin Gaignard benjamin.gaignard@linaro.org a écrit :

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Le lun. 16 déc. 2019 à 09:28, Benjamin Gaignard benjamin.gaignard@linaro.org a écrit :

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Le mer. 4 déc. 2019 à 17:47, Jani Nikula jani.nikula@linux.intel.com a écrit :

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On Thu, 28 Nov 2019, Benjamin Gaignard benjamin.gaignard@st.com wrote:

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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);

Again, someone needs to check if crc4 should be *used* instead of thrown away. Blindly throwing stuff out is not the way to go.

Hi Dave,

• Lyude who has been hacking in this code recently

gentle ping for the reviewers,

hi-actually yes, we should probably be using this instead of just dropping this. Also, I didn't write this code originally I just refactored a bunch of it - Dave Airlied is the original author, but the original version of this code was written ages ago. tbh, I think it's a safe bet to say that they probably did mean to use this but forgot to and no one noticed until now.

Hi,

Any clue about how to use crc value ? Does it have to be checked against something else ? If crc are not matching what should we do of the data copied just before ?

Benjamin

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Thanks, Benjamin

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Your are the original writer of this code, could you tell us if we can drop crc4 ao if there is something else that I have misunderstood ?

Thanks, Benjamin

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BR, Jani.

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          /* 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]);

-- Jani Nikula, Intel Open Source Graphics Center _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- Cheers, Lyude Paul