// SPDX-License-Identifier: GPL-2.0
// ChromeOS EC communication protocol helper functions
//
// Copyright (C) 2015 Google, Inc
#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/limits.h>
#include <linux/module.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/slab.h>
#include <linux/unaligned.h>
#include "cros_ec_trace.h"
#define EC_COMMAND_RETRIES 50
#define RWSIG_CONTINUE_RETRIES 8
#define RWSIG_CONTINUE_MAX_ERRORS_IN_ROW 3
static const int cros_ec_error_map[] = {
[EC_RES_INVALID_COMMAND] = -EOPNOTSUPP,
[EC_RES_ERROR] = -EIO,
[EC_RES_INVALID_PARAM] = -EINVAL,
[EC_RES_ACCESS_DENIED] = -EACCES,
[EC_RES_INVALID_RESPONSE] = -EPROTO,
[EC_RES_INVALID_VERSION] = -ENOPROTOOPT,
[EC_RES_INVALID_CHECKSUM] = -EBADMSG,
[EC_RES_IN_PROGRESS] = -EINPROGRESS,
[EC_RES_UNAVAILABLE] = -ENODATA,
[EC_RES_TIMEOUT] = -ETIMEDOUT,
[EC_RES_OVERFLOW] = -EOVERFLOW,
[EC_RES_INVALID_HEADER] = -EBADR,
[EC_RES_REQUEST_TRUNCATED] = -EBADR,
[EC_RES_RESPONSE_TOO_BIG] = -EFBIG,
[EC_RES_BUS_ERROR] = -EFAULT,
[EC_RES_BUSY] = -EBUSY,
[EC_RES_INVALID_HEADER_VERSION] = -EBADMSG,
[EC_RES_INVALID_HEADER_CRC] = -EBADMSG,
[EC_RES_INVALID_DATA_CRC] = -EBADMSG,
[EC_RES_DUP_UNAVAILABLE] = -ENODATA,
};
static int cros_ec_map_error(uint32_t result)
{
int ret = 0;
if (result != EC_RES_SUCCESS) {
if (result < ARRAY_SIZE(cros_ec_error_map) && cros_ec_error_map[result])
ret = cros_ec_error_map[result];
else
ret = -EPROTO;
}
return ret;
}
static int prepare_tx(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
struct ec_host_request *request;
u8 *out;
int i;
u8 csum = 0;
if (msg->outsize + sizeof(*request) > ec_dev->dout_size)
return -EINVAL;
out = ec_dev->dout;
request = (struct ec_host_request *)out;
request->struct_version = EC_HOST_REQUEST_VERSION;
request->checksum = 0;
request->command = msg->command;
request->command_version = msg->version;
request->reserved = 0;
request->data_len = msg->outsize;
for (i = 0; i < sizeof(*request); i++)
csum += out[i];
/* Copy data and update checksum */
memcpy(out + sizeof(*request), msg->data, msg->outsize);
for (i = 0; i < msg->outsize; i++)
csum += msg->data[i];
