mlxsw: core_linecards: Expose HW revision and INI version

Implement info_get() to expose HW revision of a linecard and loaded INI
version.

Example:

$ devlink dev info auxiliary/mlxsw_core.lc.0
auxiliary/mlxsw_core.lc.0:
  versions:
      fixed:
        hw.revision 0
      running:
        ini.version 4
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/networking/devlink/mlxsw.rst

@@ -58,6 +58,24 @@ The ``mlxsw`` driver reports the following versions
      - running
      - Three digit firmware version
 
+Line card auxiliary device info versions
+========================================
+
+The ``mlxsw`` driver reports the following versions for line card auxiliary device
+
+.. list-table:: devlink info versions implemented
+   :widths: 5 5 90
+
+   * - Name
+     - Type
+     - Description
+   * - ``hw.revision``
+     - fixed
+     - The hardware revision for this line card
+   * - ``ini.version``
+     - running
+     - Version of line card INI loaded
+
 Driver-specific Traps
 =====================
 

drivers/net/ethernet/mellanox/mlxsw/core.h

@@ -601,6 +601,10 @@ mlxsw_linecard_get(struct mlxsw_linecards *linecards, u8 slot_index)
 	return &linecards->linecards[slot_index - 1];
 }
 
+int mlxsw_linecard_devlink_info_get(struct mlxsw_linecard *linecard,
+				    struct devlink_info_req *req,
+				    struct netlink_ext_ack *extack);
+
 int mlxsw_linecards_init(struct mlxsw_core *mlxsw_core,
 			 const struct mlxsw_bus_info *bus_info);
 void mlxsw_linecards_fini(struct mlxsw_core *mlxsw_core);

drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c

@@ -98,7 +98,18 @@ void mlxsw_linecard_bdev_del(struct mlxsw_linecard *linecard)
 	linecard->bdev = NULL;
 }
 
+static int mlxsw_linecard_dev_devlink_info_get(struct devlink *devlink,
+					       struct devlink_info_req *req,
+					       struct netlink_ext_ack *extack)
+{
+	struct mlxsw_linecard_dev *linecard_dev = devlink_priv(devlink);
+	struct mlxsw_linecard *linecard = linecard_dev->linecard;
+
+	return mlxsw_linecard_devlink_info_get(linecard, req, extack);
+}
+
 static const struct devlink_ops mlxsw_linecard_dev_devlink_ops = {
+	.info_get			= mlxsw_linecard_dev_devlink_info_get,
 };
 
 static int mlxsw_linecard_bdev_probe(struct auxiliary_device *adev,

drivers/net/ethernet/mellanox/mlxsw/core_linecards.c

@@ -226,6 +226,34 @@ void mlxsw_linecards_event_ops_unregister(struct mlxsw_core *mlxsw_core,
 }
 EXPORT_SYMBOL(mlxsw_linecards_event_ops_unregister);
 
+int mlxsw_linecard_devlink_info_get(struct mlxsw_linecard *linecard,
+				    struct devlink_info_req *req,
+				    struct netlink_ext_ack *extack)
+{
+	char buf[32];
+	int err;
+
+	mutex_lock(&linecard->lock);
+	if (WARN_ON(!linecard->provisioned)) {
+		err = -EOPNOTSUPP;
+		goto unlock;
+	}
+
+	sprintf(buf, "%d", linecard->hw_revision);
+	err = devlink_info_version_fixed_put(req, "hw.revision", buf);
+	if (err)
+		goto unlock;
+
+	sprintf(buf, "%d", linecard->ini_version);
+	err = devlink_info_version_running_put(req, "ini.version", buf);
+	if (err)
+		goto unlock;
+
+unlock:
+	mutex_unlock(&linecard->lock);
+	return err;
+}
+
 static int
 mlxsw_linecard_provision_set(struct mlxsw_linecard *linecard, u8 card_type,
 			     u16 hw_revision, u16 ini_version)