blob: 881db34a96b91e01fb588a05d73da6c7b78c01a0 [file] [log] [blame]
// Copyright 2019 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <base/check_op.h>
#include <base/logging.h>
#include <base/threading/thread.h>
#include <base/time/time.h>
#include "libec/ec_command.h"
namespace ec {
* Represents an "async" EC command. Note that the EC codebase does not
* support true asynchronous commands. All commands are expected to return
* within a certain deadline (currently 200 ms). To handle longer-running
* commands, the EC codebase has adopted a style where a command is first
* started and then the result is polled for by specifying an |action| in the
* command's request parameters. See EC_CMD_FLASH_ERASE and EC_CMD_ADD_ENTROPY
* for examples.
template <typename O, typename I>
class EcCommandAsync : public EcCommand<O, I> {
struct Options {
int poll_for_result_num_attempts = 20;
base::TimeDelta poll_interval = base::TimeDelta::FromMilliseconds(100);
* When polling for the result, the EC should normally return EC_RES_BUSY
* when the command is still being processed. However, some commands
* cause the EC to temporarily stop responding to EC commands and the ioctl
* times out. Those commands should set validate_poll_result to false to
* ignore that error and continue polling until the timeout is hit.
bool validate_poll_result = true;
EcCommandAsync(uint32_t cmd,
uint8_t async_result_action,
const Options& options,
uint32_t ver = 0,
const O& req = {})
: EcCommand<O, I>(cmd, ver, req),
options_(options) {}
bool Run(int fd) override {
CHECK_GT(options_.poll_for_result_num_attempts, 0);
if (!BaseCmd::Run(fd)) {
LOG(ERROR) << "Failed to start command";
return false;
int num_attempts = options_.poll_for_result_num_attempts;
while (num_attempts--) {
BaseCmd::Req()->action = async_result_action_;
auto ret = BaseCmd::Result();
if (ret == EC_RES_SUCCESS) {
return true;
if (options_.validate_poll_result && ret != EC_RES_BUSY) {
LOG(ERROR) << "Failed to get command result, ret: " << ret;
return false;
LOG(ERROR) << "Timed out polling for command 0x" << std::hex
<< BaseCmd::data_.cmd.command;
return false;
const Options& options() const { return options_; }
using BaseCmd = EcCommand<O, I>;
uint8_t async_result_action_ = 0;
Options options_;
} // namespace ec