Hi Tim,
On 14/6/19 13:15, Enric Balletbo i Serra wrote:
> From: Tim Wawrzynczak <twawrzync...@chromium.org>
>
> 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 <twawrzync...@chromium.org>
> [rework based on Tim's first approach]
> Signed-off-by: Enric Balletbo i Serra <enric.balle...@collabora.com>
Applied this patch and the others in the series for chrome-platform-5.3
Thanks,
~ Enric
> ---
> Hi Tim,
>
> Sorry for beating around the bush a bit. I did a small rework of the
> latest patch you sent and now is more close to the first versions you
> sent. I was spinning around the idea if we should expose the attribute
> when the command is supported or not and I ended with the conclusion,
> however, I think makes sense for sysfs attributes, but I'd prefer
> simplicity in the code for debugfs, at the end, if we try to read a file
> for a non supported command we will get an error which is also useful
> debug information.
>
> Could you recheck that the patch still works and that I didn't break
> anything, please?
>
> Cheers,
> ~ Enric
>
> Documentation/ABI/testing/debugfs-cros-ec | 8 +++++
> drivers/platform/chrome/cros_ec_debugfs.c | 38 +++++++++++++++++++++++
> 2 files changed, 46 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..c91da2d374aa
> --- /dev/null
> +++ b/Documentation/ABI/testing/debugfs-cros-ec
> @@ -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.
> diff --git a/drivers/platform/chrome/cros_ec_debugfs.c
> b/drivers/platform/chrome/cros_ec_debugfs.c
> index 4578eb3e0731..970ba13df9a1 100644
> --- a/drivers/platform/chrome/cros_ec_debugfs.c
> +++ b/drivers/platform/chrome/cros_ec_debugfs.c
> @@ -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);
>
