iwlwifi: LTR updates

New FW versions introduces LTR feature enablement by default.
For such FW versions, driver (mvm/xvt) should not send
host command to enable LTR feature, also it should be possible to
override LTR configuration through the debugfs.

1. Send LTR feature enablement command only for FW versions
which does not advertises SET_LTR_GEN2 capability.
2. Implement ltr_config file in debugfs for LTR configuration override.
Signed-off-by: Alex Malamud <alex.malamud@intel.com>

drivers/net/wireless/intel/iwlwifi/fw/file.h

@@ -441,9 +441,10 @@ enum iwl_ucode_tlv_capa {
 	IWL_UCODE_TLV_CAPA_DYNAMIC_QUOTA                = (__force iwl_ucode_tlv_capa_t)44,
 	IWL_UCODE_TLV_CAPA_COEX_SCHEMA_2		= (__force iwl_ucode_tlv_capa_t)45,
 	IWL_UCODE_TLV_CAPA_CHANNEL_SWITCH_CMD		= (__force iwl_ucode_tlv_capa_t)46,
-	IWL_UCODE_TLV_CAPA_ULTRA_HB_CHANNELS		= (__force iwl_ucode_tlv_capa_t)48,
 	IWL_UCODE_TLV_CAPA_FTM_CALIBRATED		= (__force iwl_ucode_tlv_capa_t)47,
+	IWL_UCODE_TLV_CAPA_ULTRA_HB_CHANNELS		= (__force iwl_ucode_tlv_capa_t)48,
 	IWL_UCODE_TLV_CAPA_CS_MODIFY			= (__force iwl_ucode_tlv_capa_t)49,
+	IWL_UCODE_TLV_CAPA_SET_LTR_GEN2			= (__force iwl_ucode_tlv_capa_t)50,
 
 	/* set 2 */
 	IWL_UCODE_TLV_CAPA_EXTENDED_DTS_MEASURE		= (__force iwl_ucode_tlv_capa_t)64,

drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c

@@ -1758,6 +1758,38 @@ iwl_dbgfs_uapsd_noagg_bssids_read(struct file *file, char __user *user_buf,
 	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 }
 
+static ssize_t
+iwl_dbgfs_ltr_config_write(struct iwl_mvm *mvm,
+			   char *buf, size_t count, loff_t *ppos)
+{
+	int ret;
+	struct iwl_ltr_config_cmd ltr_config = {0};
+
+	if (!iwl_mvm_firmware_running(mvm))
+		return -EIO;
+
+	if (sscanf(buf, "%x,%x,%x,%x,%x,%x,%x",
+		   &ltr_config.flags,
+		   &ltr_config.static_long,
+		   &ltr_config.static_short,
+		   &ltr_config.ltr_cfg_values[0],
+		   &ltr_config.ltr_cfg_values[1],
+		   &ltr_config.ltr_cfg_values[2],
+		   &ltr_config.ltr_cfg_values[3]) != 7) {
+		return -EINVAL;
+	}
+
+	mutex_lock(&mvm->mutex);
+	ret = iwl_mvm_send_cmd_pdu(mvm, LTR_CONFIG, 0, sizeof(ltr_config),
+				   &ltr_config);
+	mutex_unlock(&mvm->mutex);
+
+	if (ret)
+		IWL_ERR(mvm, "failed to send ltr configuration cmd\n");
+
+	return ret ?: count;
+}
+
 MVM_DEBUGFS_READ_WRITE_FILE_OPS(prph_reg, 64);
 
 /* Device wide debugfs entries */
@@ -1806,6 +1838,8 @@ MVM_DEBUGFS_READ_WRITE_STA_FILE_OPS(amsdu_len, 16);
 
 MVM_DEBUGFS_READ_WRITE_FILE_OPS(he_sniffer_params, 32);
 
+MVM_DEBUGFS_WRITE_FILE_OPS(ltr_config, 512);
+
 static ssize_t iwl_dbgfs_mem_read(struct file *file, char __user *user_buf,
 				  size_t count, loff_t *ppos)
 {
@@ -1993,6 +2027,9 @@ void iwl_mvm_dbgfs_register(struct iwl_mvm *mvm, struct dentry *dbgfs_dir)
 #endif
 	MVM_DEBUGFS_ADD_FILE(he_sniffer_params, mvm->debugfs_dir, 0600);
 
+	if (fw_has_capa(&mvm->fw->ucode_capa, IWL_UCODE_TLV_CAPA_SET_LTR_GEN2))
+		MVM_DEBUGFS_ADD_FILE(ltr_config, mvm->debugfs_dir, 0200);
+
 	debugfs_create_bool("enable_scan_iteration_notif", 0600,
 			    mvm->debugfs_dir, &mvm->scan_iter_notif_enabled);
 	debugfs_create_bool("drop_bcn_ap_mode", 0600, mvm->debugfs_dir,

drivers/net/wireless/intel/iwlwifi/mvm/fw.c

@@ -1302,7 +1302,8 @@ int iwl_mvm_up(struct iwl_mvm *mvm)
 	iwl_mvm_tt_tx_backoff(mvm, 0);
 #endif
 
-	WARN_ON(iwl_mvm_config_ltr(mvm));
+	if (!fw_has_capa(&mvm->fw->ucode_capa, IWL_UCODE_TLV_CAPA_SET_LTR_GEN2))
+		WARN_ON(iwl_mvm_config_ltr(mvm));
 
 	ret = iwl_mvm_power_update_device(mvm);
 	if (ret)