2020-05-26 18:58:07

by Gwendal Grignou

Subject: [PATCH v2] platform: cros_ec_debugfs: control uptime information request

When EC does not support uptime command (EC_CMD_GET_UPTIME_INFO),
do not create the uptime sysfs entry point.
User space application will not probe the file needlessly.

The EC console log will not contain EC_CMD_GET_UPTIME_INFO anymore.

Signed-off-by: Gwendal Grignou <[email protected]>
---
drivers/platform/chrome/cros_ec_debugfs.c | 24 +++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c
index 6ae484989d1f5..303a8c4686f89 100644
--- a/drivers/platform/chrome/cros_ec_debugfs.c
+++ b/drivers/platform/chrome/cros_ec_debugfs.c
@@ -243,6 +243,25 @@ static ssize_t cros_ec_pdinfo_read(struct file *file,
read_buf, p - read_buf);
}

+static bool cros_ec_uptime_is_supported(struct cros_ec_device *ec_dev)
+{
+ struct {
+ struct cros_ec_command cmd;
+ struct ec_response_uptime_info resp;
+ } __packed msg = {};
+ int ret;
+
+ msg.cmd.command = EC_CMD_GET_UPTIME_INFO;
+ msg.cmd.insize = sizeof(msg.resp);
+
+ ret = cros_ec_cmd_xfer_status(ec_dev, &msg.cmd);
+ if (ret == -EPROTO && msg.cmd.result == EC_RES_INVALID_COMMAND)
+ return false;
+
+ /* Other errors maybe a transient error, do not rule about support. */
+ return true;
+}
+
static ssize_t cros_ec_uptime_read(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
@@ -445,8 +464,9 @@ 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);
+ if (cros_ec_uptime_is_supported(ec->ec_dev))
+ debugfs_create_file("uptime", 0444, debug_info->dir, debug_info,
+ &cros_ec_uptime_fops);

debugfs_create_x32("last_resume_result", 0444, debug_info->dir,
&ec->ec_dev->last_resume_result);
--
2.27.0.rc0.183.gde8f92d652-goog

2020-06-25 11:55:39

by Enric Balletbo i Serra

Subject: Re: [PATCH v2] platform: cros_ec_debugfs: control uptime information request

Hi Gwendal,

Thank you for your patch.

On 26/5/20 20:53, Gwendal Grignou wrote:
> When EC does not support uptime command (EC_CMD_GET_UPTIME_INFO),
> do not create the uptime sysfs entry point.
> User space application will not probe the file needlessly.
>
> The EC console log will not contain EC_CMD_GET_UPTIME_INFO anymore.
>
> Signed-off-by: Gwendal Grignou <[email protected]>

Applied for 5.9

> ---
> drivers/platform/chrome/cros_ec_debugfs.c | 24 +++++++++++++++++++++--
> 1 file changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c
> index 6ae484989d1f5..303a8c4686f89 100644
> --- a/drivers/platform/chrome/cros_ec_debugfs.c
> +++ b/drivers/platform/chrome/cros_ec_debugfs.c
> @@ -243,6 +243,25 @@ static ssize_t cros_ec_pdinfo_read(struct file *file,
> read_buf, p - read_buf);
> }
>
> +static bool cros_ec_uptime_is_supported(struct cros_ec_device *ec_dev)
> +{
> + struct {
> + struct cros_ec_command cmd;
> + struct ec_response_uptime_info resp;
> + } __packed msg = {};
> + int ret;
> +
> + msg.cmd.command = EC_CMD_GET_UPTIME_INFO;
> + msg.cmd.insize = sizeof(msg.resp);
> +
> + ret = cros_ec_cmd_xfer_status(ec_dev, &msg.cmd);
> + if (ret == -EPROTO && msg.cmd.result == EC_RES_INVALID_COMMAND)
> + return false;
> +
> + /* Other errors maybe a transient error, do not rule about support. */
> + return true;
> +}
> +
> static ssize_t cros_ec_uptime_read(struct file *file, char __user *user_buf,
> size_t count, loff_t *ppos)
> {
> @@ -445,8 +464,9 @@ 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);
> + if (cros_ec_uptime_is_supported(ec->ec_dev))
> + debugfs_create_file("uptime", 0444, debug_info->dir, debug_info,
> + &cros_ec_uptime_fops);
>
> debugfs_create_x32("last_resume_result", 0444, debug_info->dir,
> &ec->ec_dev->last_resume_result);
>