// SPDX-License-Identifier: GPL-2.0
// ChromeOS EC communication protocol helper functions
//
// Copyright (C) 2015 Google, Inc
#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
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];
request->checksum = -csum;
return sizeof(*request) + msg->outsize;
}
static int prepare_tx_legacy(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
u8 *out;
u8 csum;
int i;
if (msg->outsize > EC_PROTO2_MAX_PARAM_SIZE)
return -EINVAL;
out = ec_dev->dout;
out[0] = EC_CMD_VERSION0 + msg->version;
out[1] = msg->command;
out[2] = msg->outsize;
csum = out[0] + out[1] + out[2];
for (i = 0; i < msg->outsize; i++)
csum += out[EC_MSG_TX_HEADER_BYTES + i] = msg->data[i];
out[EC_MSG_TX_HEADER_BYTES + msg->outsize] = csum;
return EC_MSG_TX_PROTO_BYTES + msg->outsize;
}
static int cros_ec_xfer_command(struct cros_ec_device *ec_dev, struct cros_ec_command *msg)
{
int ret;
int (*xfer_fxn)(struct cros_ec_device *ec, struct cros_ec_command *msg);
if (ec_dev->proto_version > 2)
xfer_fxn = ec_dev->pkt_xfer;
else
xfer_fxn = ec_dev->cmd_xfer;
if (!xfer_fxn) {
/*
* This error can happen if a communication error happened and
* the EC is trying to use protocol v2, on an underlying
* communication mechanism that does not support v2.
*/
dev_err_once(ec_dev->dev, "missing EC transfer API, cannot send command\n");
return -EIO;
}
trace_cros_ec_request_start(msg);
ret = (*xfer_fxn)(ec_dev, msg);
trace_cros_ec_request_done(msg, ret);
return ret;
}
static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t *result)
{
struct {
struct cros_ec_command msg;
struct ec_response_get_comms_status status;
} __packed buf;
struct cros_ec_command *msg = &buf.msg;
struct ec_response_get_comms_status *status = &buf.status;
int ret = 0, i;
msg->version = 0;
msg->command = EC_CMD_GET_COMMS_STATUS;
msg->insize = sizeof(*status);
msg->outsize = 0;
/* Query the EC's status until it's no longer busy or we encounter an error. */
for (i = 0; i < EC_COMMAND_RETRIES; ++i) {
usleep_range(10000, 11000);
ret = cros_ec_xfer_command(ec_dev, msg);
if (ret == -EAGAIN)
continue;
if (ret < 0)
return ret;
*result = msg->result;
if (msg->result != EC_RES_SUCCESS)
return ret;
if (ret == 0) {
ret = -EPROTO;
break;
}
if (!(status->flags & EC_COMMS_STATUS_PROCESSING))
return ret;
}
if (i >= EC_COMMAND_RETRIES)
ret = -EAGAIN;
return ret;
}
static int cros_ec_send_command(struct cros_ec_device *ec_dev, struct cros_ec_command *msg)
{
int ret = cros_ec_xfer_command(ec_dev, msg);
if (msg->result == EC_RES_IN_PROGRESS)
ret = cros_ec_wait_until_complete(ec_dev, &msg->result);
return ret;
}
/**
* cros_ec_prepare_tx() - Prepare an outgoing message in the output buffer.
* @ec_dev: Device to register.
* @msg: Message to write.
*
* This is used by all ChromeOS EC drivers to prepare the outgoing message
* according to different protocol versions.
*
* Return: number of prepared bytes on success or negative error code.
*/
int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
if (ec_dev->proto_version > 2)
return prepare_tx(ec_dev, msg);
return prepare_tx_legacy(ec_dev, msg);
}
EXPORT_SYMBOL(cros_ec_prepare_tx);
/**
* cros_ec_check_result() - Check ec_msg->result.
* @ec_dev: EC device.
* @msg: Message to check.
*
* This is used by ChromeOS EC drivers to check the ec_msg->result for
* EC_RES_IN_PROGRESS and to warn about them.
*
* The function should not check for furthermore error codes. Otherwise,
* it would break the ABI.
*
* Return: -EAGAIN if ec_msg->result == EC_RES_IN_PROGRESS. Otherwise, 0.
*/
int cros_ec_check_result(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
switch (msg->result) {
case EC_RES_SUCCESS:
return 0;
case EC_RES_IN_PROGRESS:
dev_dbg(ec_dev->dev, "command 0x%02x in progress\n",
msg->command);
return -EAGAIN;
default:
dev_dbg(ec_dev->dev, "command 0x%02x returned %d\n",
msg->command, msg->result);
return 0;
}
}
EXPORT_SYMBOL(cros_ec_check_result);
/**
* cros_ec_get_host_event_wake_mask
*
* Get the mask of host events that cause wake from suspend.
*
* @ec_dev: EC device to call
* @mask: result when function returns 0.
*
* LOCKING:
* the caller has ec_dev->lock mutex, or the caller knows there is
* no other command in progress.
*/
static int cros_ec_get_host_event_wake_mask(struct cros_ec_device *ec_dev, uint32_t *mask)
{
struct cros_ec_command *msg;
struct ec_response_host_event_mask *r;
int ret, mapped;
msg = kzalloc(sizeof(*msg) + sizeof(*r), GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->command = EC_CMD_HOST_EVENT_GET_WAKE_MASK;
msg->insize = sizeof(*r);
ret = cros_ec_send_command(ec_dev, msg);
if (ret < 0)
goto exit;
mapped = cros_ec_map_error(msg->result);
if (mapped) {
ret = mapped;
goto exit;
}
if (ret == 0) {
ret = -EPROTO;
goto exit;
}
r = (struct ec_response_host_event_mask *)msg->data;
*mask = r->mask;
ret = 0;
exit:
kfree(msg);
return ret;
}
static int cros_ec_get_proto_info(struct cros_ec_device *ec_dev, int devidx)
{
struct cros_ec_command *msg;
struct ec_response_get_protocol_info *info;
int ret, mapped;
ec_dev->proto_version = 3;
if (devidx > 0)
ec_dev->max_passthru = 0;
msg = kzalloc(sizeof(*msg) + sizeof(*info), GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->command = EC_CMD_PASSTHRU_OFFSET(devidx) | EC_CMD_GET_PROTOCOL_INFO;
msg->insize = sizeof(*info);
ret = cros_ec_send_command(ec_dev, msg);
/*
* Send command once again when timeout occurred.
* Fingerprint MCU (FPMCU) is restarted during system boot which
* introduces small window in which FPMCU won't respond for any
* messages sent by kernel. There is no need to wait before next
* attempt because we waited at least EC_MSG_DEADLINE_MS.
*/
if (ret == -ETIMEDOUT)
ret = cros_ec_send_command(ec_dev, msg);
if (ret < 0) {
dev_dbg(ec_dev->dev,
"failed to check for EC[%d] protocol version: %d\n",
devidx, ret);
goto exit;
}
mapped = cros_ec_map_error(msg->result);
if (mapped) {
ret = mapped;
goto exit;
}
if (ret == 0) {
ret = -EPROTO;
goto exit;
}
info = (struct ec_response_get_protocol_info *)msg->data;
switch (devidx) {
case CROS_EC_DEV_EC_INDEX:
ec_dev->max_request = info->max_request_packet_size -
sizeof(struct ec_host_request);
ec_dev->max_response = info->max_response_packet_size -
sizeof(struct ec_host_response);
ec_dev->proto_version = min(EC_HOST_REQUEST_VERSION,
fls(info->protocol_versions) - 1);
ec_dev->din_size = info->max_response_packet_size + EC_MAX_RESPONSE_OVERHEAD;
ec_dev->dout_size = info->max_request_packet_size + EC_MAX_REQUEST_OVERHEAD;
dev_dbg(ec_dev->dev, "using proto v%u\n", ec_dev->proto_version);
break;
case CROS_EC_DEV_PD_INDEX:
ec_dev->max_passthru = info->max_request_packet_size -
sizeof(struct ec_host_request);
dev_dbg(ec_dev->dev, "found PD chip\n");
break;
default:
dev_dbg(ec_dev->dev, "unknown passthru index: %d\n", devidx);
break;
}
ret = 0;
exit:
kfree(msg);
return ret;
}
static int cros_ec_get_proto_info_legacy(struct cros_ec_device *ec_dev)
{
struct cros_ec_command *msg;
struct ec_params_hello *params;
struct ec_response_hello *response;
int ret, mapped;
ec_dev->proto_version = 2;
msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*response)), GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->command = EC_CMD_HELLO;
msg->insize = sizeof(*response);
msg->outsize = sizeof(*params);
params = (struct ec_params_hello *)msg->data;
params->in_data = 0xa0b0c0d0;
ret = cros_ec_send_command(ec_dev, msg);
if (ret < 0) {
dev_dbg(ec_dev->dev, "EC failed to respond to v2 hello: %d\n", ret);
goto exit;
}
mapped = cros_ec_map_error(msg->result);
if (mapped) {
ret = mapped;
dev_err(ec_dev->dev, "EC responded to v2 hello with error: %d\n", msg->result);
goto exit;
}
if (ret == 0) {
ret = -EPROTO;
goto exit;
}
response = (struct ec_response_hello *)msg->data;
if (response->out_data != 0xa1b2c3d4) {
dev_err(ec_dev->dev,
"EC responded to v2 hello with bad result: %u\n",
response->out_data);
ret = -EBADMSG;
goto exit;
}
ec_dev->max_request = EC_PROTO2_MAX_PARAM_SIZE;
ec_dev->max_response = EC_PROTO2_MAX_PARAM_SIZE;
ec_dev->max_passthru = 0;
ec_dev->pkt_xfer = NULL;
ec_dev->din_size = EC_PROTO2_MSG_BYTES;
ec_dev->dout_size = EC_PROTO2_MSG_BYTES;
dev_dbg(ec_dev->dev, "falling back to proto v2\n");
ret = 0;
exit:
kfree(msg);
return ret;
}
/**
* cros_ec_get_host_command_version_mask
*
* Get the version mask of a given command.
*
* @ec_dev: EC device to call
* @cmd: command to get the version of.
* @mask: result when function returns 0.
*
* @return 0 on success, error code otherwise
*
* LOCKING:
* the caller has ec_dev->lock mutex or the caller knows there is
* no other command in progress.
*/
static int cros_ec_get_host_command_version_mask(struct cros_ec_device *ec_dev, u16 cmd, u32 *mask)
{
struct ec_params_get_cmd_versions *pver;
struct ec_response_get_cmd_versions *rver;
struct cros_ec_command *msg;
int ret, mapped;
msg = kmalloc(sizeof(*msg) + max(sizeof(*rver), sizeof(*pver)),
GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->version = 0;
msg->command = EC_CMD_GET_CMD_VERSIONS;
msg->insize = sizeof(*rver);
msg->outsize = sizeof(*pver);
pver = (struct ec_params_get_cmd_versions *)msg->data;
pver->cmd = cmd;
ret = cros_ec_send_command(ec_dev, msg);
if (ret < 0)
goto exit;
mapped = cros_ec_map_error(msg->result);
if (mapped) {
ret = mapped;
goto exit;
}
if (ret == 0) {
ret = -EPROTO;
goto exit;
}
rver = (struct ec_response_get_cmd_versions *)msg->data;
*mask = rver->version_mask;
ret = 0;
exit:
kfree(msg);
return ret;
}
/**
* cros_ec_query_all() - Query the protocol version supported by the
* ChromeOS EC.
* @ec_dev: Device to register.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_query_all(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
u32 ver_mask;
int ret;
/* First try sending with proto v3. */
if (!cros_ec_get_proto_info(ec_dev, CROS_EC_DEV_EC_INDEX)) {
/* Check for PD. */
cros_ec_get_proto_info(ec_dev, CROS_EC_DEV_PD_INDEX);
} else {
/* Try querying with a v2 hello message. */
ret = cros_ec_get_proto_info_legacy(ec_dev);
if (ret) {
/*
* It's possible for a test to occur too early when
* the EC isn't listening. If this happens, we'll
* test later when the first command is run.
*/
ec_dev->proto_version = EC_PROTO_VERSION_UNKNOWN;
dev_dbg(ec_dev->dev, "EC query failed: %d\n", ret);
return ret;
}
}
devm_kfree(dev, ec_dev->din);
devm_kfree(dev, ec_dev->dout);
ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
if (!ec_dev->din) {
ret = -ENOMEM;
goto exit;
}
ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
if (!ec_dev->dout) {
devm_kfree(dev, ec_dev->din);
ret = -ENOMEM;
goto exit;
}
/* Probe if MKBP event is supported */
ret = cros_ec_get_host_command_version_mask(ec_dev, EC_CMD_GET_NEXT_EVENT, &ver_mask);
if (ret < 0 || ver_mask == 0) {
ec_dev->mkbp_event_supported = 0;
} else {
ec_dev->mkbp_event_supported = fls(ver_mask);
dev_dbg(ec_dev->dev, "MKBP support version %u\n", ec_dev->mkbp_event_supported - 1);
}
/* Probe if host sleep v1 is supported for S0ix failure detection. */
ret = cros_ec_get_host_command_version_mask(ec_dev, EC_CMD_HOST_SLEEP_EVENT, &ver_mask);
ec_dev->host_sleep_v1 = (ret == 0 && (ver_mask & EC_VER_MASK(1)));
/* Get host event wake mask. */
ret = cros_ec_get_host_event_wake_mask(ec_dev, &ec_dev->host_event_wake_mask);
if (ret < 0) {
/*
* If the EC doesn't support EC_CMD_HOST_EVENT_GET_WAKE_MASK,
* use a reasonable default. Note that we ignore various
* battery, AC status, and power-state events, because (a)
* those can be quite common (e.g., when sitting at full
* charge, on AC) and (b) these are not actionable wake events;
* if anything, we'd like to continue suspending (to save
* power), not wake up.
*/
ec_dev->host_event_wake_mask = U32_MAX &
~(EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_CLOSED) |
EC_HOST_EVENT_MASK(EC_HOST_EVENT_AC_DISCONNECTED) |
EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_LOW) |
EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_CRITICAL) |
EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY) |
EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU) |
EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_STATUS));
/*
* Old ECs may not support this command. Complain about all
* other errors.
*/
if (ret != -EOPNOTSUPP)
dev_err(ec_dev->dev,
"failed to retrieve wake mask: %d\n", ret);
}
ret = 0;
exit:
return ret;
}
EXPORT_SYMBOL(cros_ec_query_all);
/**
* cros_ec_cmd_xfer() - Send a command to the ChromeOS EC.
* @ec_dev: EC device.
* @msg: Message to write.
*
* Call this to send a command to the ChromeOS EC. This should be used instead
* of calling the EC's cmd_xfer() callback directly. This function does not
* convert EC command execution error codes to Linux error codes. Most
* in-kernel users will want to use cros_ec_cmd_xfer_status() instead since
* that function implements the conversion.
*
* Return:
* >0 - EC command was executed successfully. The return value is the number
* of bytes returned by the EC (excluding the header).
* =0 - EC communication was successful. EC command execution results are
* reported in msg->result. The result will be EC_RES_SUCCESS if the
* command was executed successfully or report an EC command execution
* error.
* <0 - EC communication error. Return value is the Linux error code.
*/
int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, struct cros_ec_command *msg)
{
int ret;
mutex_lock(&ec_dev->lock);
if (ec_dev->proto_version == EC_PROTO_VERSION_UNKNOWN) {
ret = cros_ec_query_all(ec_dev);
if (ret) {
dev_err(ec_dev->dev,
"EC version unknown and query failed; aborting command\n");
mutex_unlock(&ec_dev->lock);
return ret;
}
}
if (msg->insize > ec_dev->max_response) {
dev_dbg(ec_dev->dev, "clamping message receive buffer\n");
msg->insize = ec_dev->max_response;
}
if (msg->command < EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX)) {
if (msg->outsize > ec_dev->max_request) {
dev_err(ec_dev->dev,
"request of size %u is too big (max: %u)\n",
msg->outsize,
ec_dev->max_request);
mutex_unlock(&ec_dev->lock);
return -EMSGSIZE;
}
} else {
if (msg->outsize > ec_dev->max_passthru) {
dev_err(ec_dev->dev,
"passthru rq of size %u is too big (max: %u)\n",
msg->outsize,
ec_dev->max_passthru);
mutex_unlock(&ec_dev->lock);
return -EMSGSIZE;
}
}
ret = cros_ec_send_command(ec_dev, msg);
mutex_unlock(&ec_dev->lock);
return ret;
}
EXPORT_SYMBOL(cros_ec_cmd_xfer);
/**
* cros_ec_cmd_xfer_status() - Send a command to the ChromeOS EC.
* @ec_dev: EC device.
* @msg: Message to write.
*
* Call this to send a command to the ChromeOS EC. This should be used instead of calling the EC's
* cmd_xfer() callback directly. It returns success status only if both the command was transmitted
* successfully and the EC replied with success status.
*
* Return:
* >=0 - The number of bytes transferred.
* <0 - Linux error code
*/
int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
int ret, mapped;
ret = cros_ec_cmd_xfer(ec_dev, msg);
if (ret < 0)
return ret;
mapped = cros_ec_map_error(msg->result);
if (mapped) {
dev_dbg(ec_dev->dev, "Command result (err: %d [%d])\n",
msg->result, mapped);
ret = mapped;
}
return ret;
}
EXPORT_SYMBOL(cros_ec_cmd_xfer_status);
static int get_next_event_xfer(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg,
struct ec_response_get_next_event_v3 *event,
int version, uint32_t size)
{
int ret;
msg->version = version;
msg->command = EC_CMD_GET_NEXT_EVENT;
msg->insize = size;
msg->outsize = 0;
ret = cros_ec_cmd_xfer_status(ec_dev, msg);
if (ret > 0) {
ec_dev->event_size = ret - 1;
ec_dev->event_data = *event;
}
return ret;
}
static int get_next_event(struct cros_ec_device *ec_dev)
{
struct {
struct cros_ec_command msg;
struct ec_response_get_next_event_v3 event;
} __packed buf;
struct cros_ec_command *msg = &buf.msg;
struct ec_response_get_next_event_v3 *event = &buf.event;
int cmd_version = ec_dev->mkbp_event_supported - 1;
u32 size;
memset(msg, 0, sizeof(*msg));
if (ec_dev->suspended) {
dev_dbg(ec_dev->dev, "Device suspended.\n");
return -EHOSTDOWN;
}
if (cmd_version == 0) {
size = sizeof(struct ec_response_get_next_event);
} else if (cmd_version < 3) {
size = sizeof(struct ec_response_get_next_event_v1);
} else {
/*
* The max version we support is v3. So, we speak v3 even if the
* EC says it supports v4+.
*/
cmd_version = 3;
size = sizeof(struct ec_response_get_next_event_v3);
}
return get_next_event_xfer(ec_dev, msg, event, cmd_version, size);
}
static int get_keyboard_state_event(struct cros_ec_device *ec_dev)
{
u8 buffer[sizeof(struct cros_ec_command) +
sizeof(ec_dev->event_data.data)];
struct cros_ec_command *msg = (struct cros_ec_command *)&buffer;
msg->version = 0;
msg->command = EC_CMD_MKBP_STATE;
msg->insize = sizeof(ec_dev->event_data.data);
msg->outsize = 0;
ec_dev->event_size = cros_ec_cmd_xfer_status(ec_dev, msg);
ec_dev->event_data.event_type = EC_MKBP_EVENT_KEY_MATRIX;
memcpy(&ec_dev->event_data.data, msg->data,
sizeof(ec_dev->event_data.data));
return ec_dev->event_size;
}
/**
* cros_ec_get_next_event() - Fetch next event from the ChromeOS EC.
* @ec_dev: Device to fetch event from.
* @wake_event: Pointer to a bool set to true upon return if the event might be
* treated as a wake event. Ignored if null.
* @has_more_events: Pointer to bool set to true if more than one event is
* pending.
* Some EC will set this flag to indicate cros_ec_get_next_event()
* can be called multiple times in a row.
* It is an optimization to prevent issuing a EC command for
* nothing or wait for another interrupt from the EC to process
* the next message.
* Ignored if null.
*
* Return: negative error code on errors; 0 for no data; or else number of
* bytes received (i.e., an event was retrieved successfully). Event types are
* written out to @ec_dev->event_data.event_type on success.
*/
int cros_ec_get_next_event(struct cros_ec_device *ec_dev,
bool *wake_event,
bool *has_more_events)
{
u8 event_type;
u32 host_event;
int ret;
u32 ver_mask;
/*
* Default value for wake_event.
* Wake up on keyboard event, wake up for spurious interrupt or link
* error to the EC.
*/
if (wake_event)
*wake_event = true;
/*
* Default value for has_more_events.
* EC will raise another interrupt if AP does not process all events
* anyway.
*/
if (has_more_events)
*has_more_events = false;
if (!ec_dev->mkbp_event_supported)
return get_keyboard_state_event(ec_dev);
ret = get_next_event(ec_dev);
/*
* -ENOPROTOOPT is returned when EC returns EC_RES_INVALID_VERSION.
* This can occur when EC based device (e.g. Fingerprint MCU) jumps to
* the RO image which doesn't support newer version of the command. In
* this case we will attempt to update maximum supported version of the
* EC_CMD_GET_NEXT_EVENT.
*/
if (ret == -ENOPROTOOPT) {
dev_dbg(ec_dev->dev,
"GET_NEXT_EVENT returned invalid version error.\n");
mutex_lock(&ec_dev->lock);
ret = cros_ec_get_host_command_version_mask(ec_dev,
EC_CMD_GET_NEXT_EVENT,
&ver_mask);
mutex_unlock(&ec_dev->lock);
if (ret < 0 || ver_mask == 0)
/*
* Do not change the MKBP supported version if we can't
* obtain supported version correctly. Please note that
* calling EC_CMD_GET_NEXT_EVENT returned
* EC_RES_INVALID_VERSION which means that the command
* is present.
*/
return -ENOPROTOOPT;
ec_dev->mkbp_event_supported = fls(ver_mask);
dev_dbg(ec_dev->dev, "MKBP support version changed to %u\n",
ec_dev->mkbp_event_supported - 1);
/* Try to get next event with new MKBP support version set. */
ret = get_next_event(ec_dev);
}
if (ret <= 0)
return ret;
if (has_more_events)
*has_more_events = ec_dev->event_data.event_type &
EC_MKBP_HAS_MORE_EVENTS;
ec_dev->event_data.event_type &= EC_MKBP_EVENT_TYPE_MASK;
if (wake_event) {
event_type = ec_dev->event_data.event_type;
host_event = cros_ec_get_host_event(ec_dev);
/*
* Sensor events need to be parsed by the sensor sub-device.
* Defer them, and don't report the wakeup here.
*/
if (event_type == EC_MKBP_EVENT_SENSOR_FIFO) {
*wake_event = false;
} else if (host_event) {
/* rtc_update_irq() already handles wakeup events. */
if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_RTC))
*wake_event = false;
/* Masked host-events should not count as wake events. */
if (!(host_event & ec_dev->host_event_wake_mask))
*wake_event = false;
}
}
return ret;
}
EXPORT_SYMBOL(cros_ec_get_next_event);
/**
* cros_ec_get_host_event() - Return a mask of event set by the ChromeOS EC.
* @ec_dev: Device to fetch event from.
*
* When MKBP is supported, when the EC raises an interrupt, we collect the
* events raised and call the functions in the ec notifier. This function
* is a helper to know which events are raised.
*
* Return: 0 on error or non-zero bitmask of one or more EC_HOST_EVENT_*.
*/
u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev)
{
u32 host_event;
if (!ec_dev->mkbp_event_supported)
return 0;
if (ec_dev->event_data.event_type != EC_MKBP_EVENT_HOST_EVENT)
return 0;
if (ec_dev->event_size != sizeof(host_event)) {
dev_warn(ec_dev->dev, "Invalid host event size\n");
return 0;
}
host_event = get_unaligned_le32(&ec_dev->event_data.data.host_event);
return host_event;
}
EXPORT_SYMBOL(cros_ec_get_host_event);
/**
* cros_ec_check_features() - Test for the presence of EC features
*
* @ec: EC device, does not have to be connected directly to the AP,
* can be daisy chained through another device.
* @feature: One of ec_feature_code bit.
*
* Call this function to test whether the ChromeOS EC supports a feature.
*
* Return: true if supported, false if not (or if an error was encountered).
*/
bool cros_ec_check_features(struct cros_ec_dev *ec, int feature)
{
struct ec_response_get_features *features = &ec->features;
int ret;
if (features->flags[0] == -1U && features->flags[1] == -1U) {
/* features bitmap not read yet */
ret = cros_ec_cmd(ec->ec_dev, 0, EC_CMD_GET_FEATURES + ec->cmd_offset,
NULL, 0, features, sizeof(*features));
if (ret < 0) {
dev_warn(ec->dev, "cannot get EC features: %d\n", ret);
memset(features, 0, sizeof(*features));
}
dev_dbg(ec->dev, "EC features %08x %08x\n",
features->flags[0], features->flags[1]);
}
return !!(features->flags[feature / 32] & EC_FEATURE_MASK_0(feature));
}
EXPORT_SYMBOL_GPL(cros_ec_check_features);
/**
* cros_ec_get_sensor_count() - Return the number of MEMS sensors supported.
*
* @ec: EC device, does not have to be connected directly to the AP,
* can be daisy chained through another device.
* Return: < 0 in case of error.
*/
int cros_ec_get_sensor_count(struct cros_ec_dev *ec)
{
/*
* Issue a command to get the number of sensor reported.
* If not supported, check for legacy mode.
*/
int ret, sensor_count;
struct ec_params_motion_sense *params;
struct ec_response_motion_sense *resp;
struct cros_ec_command *msg;
struct cros_ec_device *ec_dev = ec->ec_dev;
u8 status;
msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)),
GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->version = 1;
msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
msg->outsize = sizeof(*params);
msg->insize = sizeof(*resp);
params = (struct ec_params_motion_sense *)msg->data;
params->cmd = MOTIONSENSE_CMD_DUMP;
ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
if (ret < 0) {
sensor_count = ret;
} else {
resp = (struct ec_response_motion_sense *)msg->data;
sensor_count = resp->dump.sensor_count;
}
kfree(msg);
/*
* Check legacy mode: Let's find out if sensors are accessible
* via LPC interface.
*/
if (sensor_count < 0 && ec->cmd_offset == 0 && ec_dev->cmd_readmem) {
ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS,
1, &status);
if (ret >= 0 &&
(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
/*
* We have 2 sensors, one in the lid, one in the base.
*/
sensor_count = 2;
} else {
/*
* EC uses LPC interface and no sensors are presented.
*/
sensor_count = 0;
}
}
return sensor_count;
}
EXPORT_SYMBOL_GPL(cros_ec_get_sensor_count);
/**
* cros_ec_cmd - Send a command to the EC.
*
* @ec_dev: EC device
* @version: EC command version
* @command: EC command
* @outdata: EC command output data
* @outsize: Size of outdata
* @indata: EC command input data
* @insize: Size of indata
*
* Return: >= 0 on success, negative error number on failure.
*/
int cros_ec_cmd(struct cros_ec_device *ec_dev,
unsigned int version,
int command,
const void *outdata,
size_t outsize,
void *indata,
size_t insize)
{
struct cros_ec_command *msg;
int ret;
msg = kzalloc(sizeof(*msg) + max(insize, outsize), GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->version = version;
msg->command = command;
msg->outsize = outsize;
msg->insize = insize;
if (outsize)
memcpy(msg->data, outdata, outsize);
ret = cros_ec_cmd_xfer_status(ec_dev, msg);
if (ret < 0)
goto error;
if (insize)
memcpy(indata, msg->data, insize);
error:
kfree(msg);
return ret;
}
EXPORT_SYMBOL_GPL(cros_ec_cmd);
/**
* cros_ec_cmd_readmem - Read from EC memory.
*
* @ec_dev: EC device
* @offset: Is within EC_LPC_ADDR_MEMMAP region.
* @size: Number of bytes to read.
* @dest: EC command output data
*
* Return: >= 0 on success, negative error number on failure.
*/
int cros_ec_cmd_readmem(struct cros_ec_device *ec_dev, u8 offset, u8 size, void *dest)
{
struct ec_params_read_memmap params = {};
if (!size)
return -EINVAL;
if (ec_dev->cmd_readmem)
return ec_dev->cmd_readmem(ec_dev, offset, size, dest);
params.offset = offset;
params.size = size;
return cros_ec_cmd(ec_dev, 0, EC_CMD_READ_MEMMAP,
¶ms, sizeof(params), dest, size);
}
EXPORT_SYMBOL_GPL(cros_ec_cmd_readmem);
/**
* cros_ec_get_cmd_versions - Get supported version mask.
*
* @ec_dev: EC device
* @cmd: Command to test
*
* Return: version mask on success, negative error number on failure.
*/
int cros_ec_get_cmd_versions(struct cros_ec_device *ec_dev, u16 cmd)
{
struct ec_params_get_cmd_versions req_v0;
struct ec_params_get_cmd_versions_v1 req_v1;
struct ec_response_get_cmd_versions resp;
int ret;
if (cmd <= U8_MAX) {
req_v0.cmd = cmd;
ret = cros_ec_cmd(ec_dev, 0, EC_CMD_GET_CMD_VERSIONS,
&req_v0, sizeof(req_v0), &resp, sizeof(resp));
} else {
req_v1.cmd = cmd;
ret = cros_ec_cmd(ec_dev, 1, EC_CMD_GET_CMD_VERSIONS,
&req_v1, sizeof(req_v1), &resp, sizeof(resp));
}
if (ret == -EINVAL)
return 0; /* Command not implemented */
else if (ret < 0)
return ret;
else
return resp.version_mask;
}
EXPORT_SYMBOL_GPL(cros_ec_get_cmd_versions);
Codebase Browser
linux