OpenCloudOS-Kernel/drivers/platform/chrome/cros_ec_proto.c

948 lines
25 KiB
C
Raw Normal View History

// 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/module.h>
mfd / platform: cros_ec: Reorganize platform and mfd includes There is a bit of mess between cros-ec mfd includes and platform includes. For example, we have a linux/mfd/cros_ec.h include that exports the interface implemented in platform/chrome/cros_ec_proto.c. Or we have a linux/mfd/cros_ec_commands.h file that is non related to the multifunction device (in the sense that is not exporting any function of the mfd device). This causes crossed includes between mfd and platform/chrome subsystems and makes the code difficult to read, apart from creating 'curious' situations where a platform/chrome driver includes a linux/mfd/cros_ec.h file just to get the exported functions that are implemented in another platform/chrome driver. In order to have a better separation on what the cros-ec multifunction driver does and what the cros-ec core provides move and rework the affected includes doing: - Move cros_ec_commands.h to include/linux/platform_data/cros_ec_commands.h - Get rid of the parts that are implemented in the platform/chrome/cros_ec_proto.c driver from include/linux/mfd/cros_ec.h to a new file include/linux/platform_data/cros_ec_proto.h - Update all the drivers with the new includes, so - Drivers that only need to know about the protocol include - linux/platform_data/cros_ec_proto.h - linux/platform_data/cros_ec_commands.h - Drivers that need to know about the cros-ec mfd device also include - linux/mfd/cros_ec.h Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Series changes: 3 - Fix dereferencing pointer to incomplete type 'struct cros_ec_dev' (lkp) Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 17:53:05 +08:00
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/slab.h>
#include <asm/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_packet(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
struct ec_host_request *request;
u8 *out;
int i;
u8 csum = 0;
BUG_ON(ec_dev->proto_version != EC_HOST_REQUEST_VERSION);
BUG_ON(msg->outsize + sizeof(*request) > ec_dev->dout_size);
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 send_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);
if (msg->result == EC_RES_IN_PROGRESS) {
int i;
struct cros_ec_command *status_msg;
struct ec_response_get_comms_status *status;
status_msg = kmalloc(sizeof(*status_msg) + sizeof(*status),
GFP_KERNEL);
if (!status_msg)
return -ENOMEM;
status_msg->version = 0;
status_msg->command = EC_CMD_GET_COMMS_STATUS;
status_msg->insize = sizeof(*status);
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);
trace_cros_ec_request_start(status_msg);
ret = (*xfer_fxn)(ec_dev, status_msg);
trace_cros_ec_request_done(status_msg, ret);
mfd: cros_ec: Retry commands when EC is known to be busy Commit 001dde9400d5 ("mfd: cros ec: spi: Fix "in progress" error signaling") pointed out some bad code, but its analysis and conclusion was not 100% correct. It *is* correct that we should not propagate result==EC_RES_IN_PROGRESS for transport errors, because this has a special meaning -- that we should follow up with EC_CMD_GET_COMMS_STATUS until the EC is no longer busy. This is definitely the wrong thing for many commands, because among other problems, EC_CMD_GET_COMMS_STATUS doesn't actually retrieve any RX data from the EC, so commands that expected some data back will instead start processing junk. For such commands, the right answer is to either propagate the error (and return that error to the caller) or resend the original command (*not* EC_CMD_GET_COMMS_STATUS). Unfortunately, commit 001dde9400d5 forgets a crucial point: that for some long-running operations, the EC physically cannot respond to commands any more. For example, with EC_CMD_FLASH_ERASE, the EC may be re-flashing its own code regions, so it can't respond to SPI interrupts. Instead, the EC prepares us ahead of time for being busy for a "long" time, and fills its hardware buffer with EC_SPI_PAST_END. Thus, we expect to see several "transport" errors (or, messages filled with EC_SPI_PAST_END). So we should really translate that to a retryable error (-EAGAIN) and continue sending EC_CMD_GET_COMMS_STATUS until we get a ready status. IOW, it is actually important to treat some of these "junk" values as retryable errors. Together with commit 001dde9400d5, this resolves bugs like the following: 1. EC_CMD_FLASH_ERASE now works again (with commit 001dde9400d5, we would abort the first time we saw EC_SPI_PAST_END) 2. Before commit 001dde9400d5, transport errors (e.g., EC_SPI_RX_BAD_DATA) seen in other commands (e.g., EC_CMD_RTC_GET_VALUE) used to yield junk data in the RX buffer; they will now yield -EAGAIN return values, and tools like 'hwclock' will simply fail instead of retrieving and re-programming undefined time values Fixes: 001dde9400d5 ("mfd: cros ec: spi: Fix "in progress" error signaling") Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-05-23 08:23:10 +08:00
if (ret == -EAGAIN)
continue;
if (ret < 0)
break;
msg->result = status_msg->result;
if (status_msg->result != EC_RES_SUCCESS)
break;
status = (struct ec_response_get_comms_status *)
status_msg->data;
if (!(status->flags & EC_COMMS_STATUS_PROCESSING))
break;
}
kfree(status_msg);
}
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 intended to be used by all ChromeOS EC drivers, but at present
* only SPI uses it. Once LPC uses the same protocol it can start using it.
* I2C could use it now, with a refactor of the existing code.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
u8 *out;
u8 csum;
int i;
if (ec_dev->proto_version > 2)
return prepare_packet(ec_dev, msg);
BUG_ON(msg->outsize > EC_PROTO2_MAX_PARAM_SIZE);
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;
}
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
* errors and to warn about them.
*
* Return: 0 on success or negative error code.
*/
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
* @msg: message structure to use
* @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,
struct cros_ec_command *msg,
uint32_t *mask)
{
struct ec_response_host_event_mask *r;
int ret;
msg->command = EC_CMD_HOST_EVENT_GET_WAKE_MASK;
msg->version = 0;
msg->outsize = 0;
msg->insize = sizeof(*r);
ret = send_command(ec_dev, msg);
if (ret >= 0) {
if (msg->result == EC_RES_INVALID_COMMAND)
return -EOPNOTSUPP;
if (msg->result != EC_RES_SUCCESS)
return -EPROTO;
}
if (ret > 0) {
r = (struct ec_response_host_event_mask *)msg->data;
*mask = r->mask;
}
return ret;
}
static int cros_ec_host_command_proto_query(struct cros_ec_device *ec_dev,
int devidx,
struct cros_ec_command *msg)
{
/*
* Try using v3+ to query for supported protocols. If this
* command fails, fall back to v2. Returns the highest protocol
* supported by the EC.
* Also sets the max request/response/passthru size.
*/
int ret;
if (!ec_dev->pkt_xfer)
return -EPROTONOSUPPORT;
memset(msg, 0, sizeof(*msg));
msg->command = EC_CMD_PASSTHRU_OFFSET(devidx) | EC_CMD_GET_PROTOCOL_INFO;
msg->insize = sizeof(struct ec_response_get_protocol_info);
ret = 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 = 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);
return ret;
}
if (devidx > 0 && msg->result == EC_RES_INVALID_COMMAND)
return -ENODEV;
else if (msg->result != EC_RES_SUCCESS)
return msg->result;
return 0;
}
static int cros_ec_host_command_proto_query_v2(struct cros_ec_device *ec_dev)
{
struct cros_ec_command *msg;
struct ec_params_hello *hello_params;
struct ec_response_hello *hello_response;
int ret;
int len = max(sizeof(*hello_params), sizeof(*hello_response));
msg = kmalloc(sizeof(*msg) + len, GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->version = 0;
msg->command = EC_CMD_HELLO;
hello_params = (struct ec_params_hello *)msg->data;
msg->outsize = sizeof(*hello_params);
hello_response = (struct ec_response_hello *)msg->data;
msg->insize = sizeof(*hello_response);
hello_params->in_data = 0xa0b0c0d0;
ret = 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;
} else if (msg->result != EC_RES_SUCCESS) {
dev_err(ec_dev->dev,
"EC responded to v2 hello with error: %d\n",
msg->result);
ret = msg->result;
goto exit;
} else if (hello_response->out_data != 0xa1b2c3d4) {
dev_err(ec_dev->dev,
"EC responded to v2 hello with bad result: %u\n",
hello_response->out_data);
ret = -EBADMSG;
goto exit;
}
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
* @msg: message structure to use
* @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;
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 = send_command(ec_dev, msg);
if (ret > 0) {
rver = (struct ec_response_get_cmd_versions *)msg->data;
*mask = rver->version_mask;
}
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;
struct cros_ec_command *proto_msg;
struct ec_response_get_protocol_info *proto_info;
u32 ver_mask = 0;
int ret;
proto_msg = kzalloc(sizeof(*proto_msg) + sizeof(*proto_info),
GFP_KERNEL);
if (!proto_msg)
return -ENOMEM;
/* First try sending with proto v3. */
ec_dev->proto_version = 3;
ret = cros_ec_host_command_proto_query(ec_dev, 0, proto_msg);
if (ret == 0) {
proto_info = (struct ec_response_get_protocol_info *)
proto_msg->data;
ec_dev->max_request = proto_info->max_request_packet_size -
sizeof(struct ec_host_request);
ec_dev->max_response = proto_info->max_response_packet_size -
sizeof(struct ec_host_response);
ec_dev->proto_version =
min(EC_HOST_REQUEST_VERSION,
fls(proto_info->protocol_versions) - 1);
dev_dbg(ec_dev->dev,
"using proto v%u\n",
ec_dev->proto_version);
ec_dev->din_size = ec_dev->max_response +
sizeof(struct ec_host_response) +
EC_MAX_RESPONSE_OVERHEAD;
ec_dev->dout_size = ec_dev->max_request +
sizeof(struct ec_host_request) +
EC_MAX_REQUEST_OVERHEAD;
/*
* Check for PD
*/
ret = cros_ec_host_command_proto_query(ec_dev, 1, proto_msg);
if (ret) {
dev_dbg(ec_dev->dev, "no PD chip found: %d\n", ret);
ec_dev->max_passthru = 0;
} else {
dev_dbg(ec_dev->dev, "found PD chip\n");
ec_dev->max_passthru =
proto_info->max_request_packet_size -
sizeof(struct ec_host_request);
}
} else {
/* Try querying with a v2 hello message. */
ec_dev->proto_version = 2;
ret = cros_ec_host_command_proto_query_v2(ec_dev);
if (ret == 0) {
/* V2 hello succeeded. */
dev_dbg(ec_dev->dev, "falling back to proto v2\n");
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;
} else {
/*
* 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);
goto exit;
}
}
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, proto_msg,
&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:
kfree(proto_msg);
return ret;
}
EXPORT_SYMBOL(cros_ec_query_all);
/**
* 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;
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(1)) {
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 = send_command(ec_dev, msg);
mutex_unlock(&ec_dev->lock);
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_v1 *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_v1 event;
} __packed buf;
struct cros_ec_command *msg = &buf.msg;
struct ec_response_get_next_event_v1 *event = &buf.event;
const int cmd_version = ec_dev->mkbp_event_supported - 1;
memset(msg, 0, sizeof(*msg));
if (ec_dev->suspended) {
dev_dbg(ec_dev->dev, "Device suspended.\n");
return -EHOSTDOWN;
}
if (cmd_version == 0)
return get_next_event_xfer(ec_dev, msg, event, 0,
sizeof(struct ec_response_get_next_event));
return get_next_event_xfer(ec_dev, msg, event, cmd_version,
sizeof(struct ec_response_get_next_event_v1));
}
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;
/*
* 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);
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;
BUG_ON(!ec_dev->mkbp_event_supported);
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_command(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_command - 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_command(struct cros_ec_device *ec_dev,
unsigned int version,
int command,
void *outdata,
int outsize,
void *indata,
int 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_command);