iwlwifi: mvm: allow firmware crashes to wake system for debug

When the D3 firmware crashes, it can be helpful for debugging to
resume the system to get the SRAM snapshot to see why it crashed.
Allow enabling this with a debugfs option.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/iwlwifi/mvm/d3.c

@@ -1026,6 +1026,12 @@ static int __iwl_mvm_suspend(struct ieee80211_hw *hw,
 	if (ret)
 		goto out;
 
+#ifdef CONFIG_IWLWIFI_DEBUGFS
+	if (mvm->d3_wake_sysassert)
+		d3_cfg_cmd_data.wakeup_flags |=
+			cpu_to_le32(IWL_WAKEUP_D3_CONFIG_FW_ERROR);
+#endif
+
 	/* must be last -- this switches firmware state */
 	ret = iwl_mvm_send_cmd(mvm, &d3_cfg_cmd);
 	if (ret)

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

@@ -939,6 +939,9 @@ int iwl_mvm_dbgfs_register(struct iwl_mvm *mvm, struct dentry *dbgfs_dir)
 #ifdef CONFIG_PM_SLEEP
 	MVM_DEBUGFS_ADD_FILE(d3_sram, mvm->debugfs_dir, S_IRUSR | S_IWUSR);
 	MVM_DEBUGFS_ADD_FILE(d3_test, mvm->debugfs_dir, S_IRUSR);
+	if (!debugfs_create_bool("d3_wake_sysassert", S_IRUSR | S_IWUSR,
+				 mvm->debugfs_dir, &mvm->d3_wake_sysassert))
+		goto err;
 #endif
 
 	/*

drivers/net/wireless/iwlwifi/mvm/mvm.h

@@ -460,6 +460,7 @@ struct iwl_mvm {
 #ifdef CONFIG_PM_SLEEP
 	int gtk_ivlen, gtk_icvlen, ptk_ivlen, ptk_icvlen;
 #ifdef CONFIG_IWLWIFI_DEBUGFS
+	u32 d3_wake_sysassert; /* must be u32 for debugfs_create_bool */
 	bool d3_test_active;
 	bool store_d3_resume_sram;
 	void *d3_resume_sram;