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platform/chrome: cros_ec_debugfs: Add debugfs entry to retrieve EC uptime

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The new debugfs entry 'uptime' is being made available to userspace so that
a userspace daemon can synchronize EC logs with host time.

Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
[rework based on Tim's first approach]
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Tested-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
This commit is contained in:
Tim Wawrzynczak 2019-06-13 11:57:36 -06:00 committed by Enric Balletbo i Serra
parent 74e80d81cc
commit e90716a661
2 changed files with 46 additions and 0 deletions
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8
Documentation/ABI/testing/debugfs-cros-ec Normal file
View File

@ -0,0 +1,8 @@
What: /sys/kernel/debug/<cros-ec-device>/uptime
Date: June 2019
KernelVersion: 5.3
Description:
A u32 providing the time since EC booted in ms. This is
is used for synchronizing the AP host time with the EC
log. An error is returned if the command is not supported
by the EC or there is a communication problem.

38
drivers/platform/chrome/cros_ec_debugfs.c
View File

@ -241,6 +241,34 @@ static ssize_t cros_ec_pdinfo_read(struct file *file,
read_buf, p - read_buf);
}
static ssize_t cros_ec_uptime_read(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
struct cros_ec_debugfs *debug_info = file->private_data;
struct cros_ec_device *ec_dev = debug_info->ec->ec_dev;
struct {
struct cros_ec_command cmd;
struct ec_response_uptime_info resp;
} __packed msg = {};
struct ec_response_uptime_info *resp;
char read_buf[32];
int ret;
resp = (struct ec_response_uptime_info *)&msg.resp;
msg.cmd.command = EC_CMD_GET_UPTIME_INFO;
msg.cmd.insize = sizeof(*resp);
ret = cros_ec_cmd_xfer_status(ec_dev, &msg.cmd);
if (ret < 0)
return ret;
ret = scnprintf(read_buf, sizeof(read_buf), "%u\n",
resp->time_since_ec_boot_ms);
return simple_read_from_buffer(user_buf, count, ppos, read_buf, ret);
}
static const struct file_operations cros_ec_console_log_fops = {
.owner = THIS_MODULE,
.open = cros_ec_console_log_open,
@ -257,6 +285,13 @@ static const struct file_operations cros_ec_pdinfo_fops = {
.llseek = default_llseek,
};
const struct file_operations cros_ec_uptime_fops = {
.owner = THIS_MODULE,
.open = simple_open,
.read = cros_ec_uptime_read,
.llseek = default_llseek,
};
static int ec_read_version_supported(struct cros_ec_dev *ec)
{
struct ec_params_get_cmd_versions_v1 *params;
@ -408,6 +443,9 @@ static int cros_ec_debugfs_probe(struct platform_device *pd)
debugfs_create_file("pdinfo", 0444, debug_info->dir, debug_info,
&cros_ec_pdinfo_fops);
debugfs_create_file("uptime", 0444, debug_info->dir, debug_info,
&cros_ec_uptime_fops);
ec->debug_info = debug_info;
dev_set_drvdata(&pd->dev, ec);