From: Tim Wawrzynczak <[email protected]> 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 <[email protected]> --- Changelist: - Moved uptime file from sysfs to debugfs (/sys/kernel/debug/cros_ec/uptime) - Fixed ordering of local variables in cros_ec_uptime_read. Tested against ChromeOS kernel v4.14 --- Documentation/ABI/testing/debugfs-cros-ec | 10 +++++ drivers/platform/chrome/cros_ec_debugfs.c | 54 +++++++++++++++++++++++ 2 files changed, 64 insertions(+) create mode 100644 Documentation/ABI/testing/debugfs-cros-ec diff --git a/Documentation/ABI/testing/debugfs-cros-ec b/Documentation/ABI/testing/debugfs-cros-ec new file mode 100644 index 000000000000..24b781c67a4c --- /dev/null +++ b/Documentation/ABI/testing/debugfs-cros-ec @@ -0,0 +1,10 @@ +What: /sys/kernel/debug/cros_ec/uptime +Date: March 2019 +KernelVersion: 5.1 +Description: + Read-only. + Reads the EC's current uptime information + (using EC_CMD_GET_UPTIME_INFO) and prints + time_since_ec_boot_ms into the file. + This is used for synchronizing AP host time + with the cros_ec log. diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c index 71308766e891..3ea42008a59e 100644 --- a/drivers/platform/chrome/cros_ec_debugfs.c +++ b/drivers/platform/chrome/cros_ec_debugfs.c @@ -201,6 +201,40 @@ static int cros_ec_console_log_release(struct inode *inode, struct file *file) return 0; } +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 msg; + struct ec_response_uptime_info resp; + } __packed ec_buf; + struct ec_response_uptime_info *resp; + struct cros_ec_command *msg; + char read_buf[32]; + int ret; + + msg = &ec_buf.msg; + resp = (struct ec_response_uptime_info *)msg->data; + + msg->command = EC_CMD_GET_UPTIME_INFO; + msg->version = 0; + msg->insize = sizeof(*resp); + msg->outsize = 0; + + ret = cros_ec_cmd_xfer_status(ec_dev, msg); + 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 ssize_t cros_ec_pdinfo_read(struct file *file, char __user *user_buf, size_t count, @@ -269,6 +303,13 @@ 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; @@ -413,6 +454,15 @@ static int cros_ec_create_pdinfo(struct cros_ec_debugfs *debug_info) return 0; } +static int cros_ec_create_uptime(struct cros_ec_debugfs *debug_info) +{ + if (!debugfs_create_file("uptime", 0444, debug_info->dir, debug_info, + &cros_ec_uptime_fops)) + return -ENOMEM; + + return 0; +} + static int cros_ec_debugfs_probe(struct platform_device *pd) { struct cros_ec_dev *ec = dev_get_drvdata(pd->dev.parent); @@ -442,6 +492,10 @@ static int cros_ec_debugfs_probe(struct platform_device *pd) if (ret) goto remove_log; + ret = cros_ec_create_uptime(debug_info); + if (ret) + goto remove_log; + ec->debug_info = debug_info; dev_set_drvdata(&pd->dev, ec); -- 2.20.1
