Re: [PATCH] platform/chrome: cros_ec_debugfs: Support pd_info v2 format

From: Enric Balletbo i Serra
Date: Tue Sep 15 2020 - 08:59:11 EST


Hi Stephen, Prashant,

On 9/9/20 6:04, Stephen Boyd wrote:
> Let's try to read more information out of more modern cros_ec devices by
> using the v2 format first and then fall back to the v1 format. This
> gives us more information about things such as DP mode of the typec pins
> and the CC state, along with some more things.
>
> Cc: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
> Cc: Prashant Malani <pmalani@xxxxxxxxxxxx>
> Cc: Guenter Roeck <groeck@xxxxxxxxxxxx>
> Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
> ---
>

I saw some discussion going on in gerrit (a pity the discussion didn't happen in
mainline) Did you end with a conclusion? Can I remove this patch from my backlog?

Thanks,
Enric

> Should we move read_buf to the heap?
>
> drivers/platform/chrome/cros_ec_debugfs.c | 40 +++++++++++++++++------
> 1 file changed, 30 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c
> index 272c89837d74..4f8c902c0de6 100644
> --- a/drivers/platform/chrome/cros_ec_debugfs.c
> +++ b/drivers/platform/chrome/cros_ec_debugfs.c
> @@ -195,28 +195,31 @@ static ssize_t cros_ec_pdinfo_read(struct file *file,
> size_t count,
> loff_t *ppos)
> {
> - char read_buf[EC_USB_PD_MAX_PORTS * 40], *p = read_buf;
> + char read_buf[EC_USB_PD_MAX_PORTS * 64], *p = read_buf;
> 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;
> union {
> - struct ec_response_usb_pd_control_v1 resp;
> + struct ec_response_usb_pd_control_v2 resp_v2;
> + struct ec_response_usb_pd_control_v1 resp_v1;
> struct ec_params_usb_pd_control params;
> };
> } __packed ec_buf;
> struct cros_ec_command *msg;
> - struct ec_response_usb_pd_control_v1 *resp;
> + struct ec_response_usb_pd_control_v1 *resp_v1;
> + struct ec_response_usb_pd_control_v2 *resp_v2;
> struct ec_params_usb_pd_control *params;
> int i;
>
> msg = &ec_buf.msg;
> params = (struct ec_params_usb_pd_control *)msg->data;
> - resp = (struct ec_response_usb_pd_control_v1 *)msg->data;
> + resp_v1 = (struct ec_response_usb_pd_control_v1 *)msg->data;
> + resp_v2 = (struct ec_response_usb_pd_control_v2 *)msg->data;
>
> msg->command = EC_CMD_USB_PD_CONTROL;
> - msg->version = 1;
> - msg->insize = sizeof(*resp);
> + msg->version = 2;
> + msg->insize = sizeof(*resp_v2);
> msg->outsize = sizeof(*params);
>
> /*
> @@ -229,13 +232,30 @@ static ssize_t cros_ec_pdinfo_read(struct file *file,
> params->mux = 0;
> params->swap = 0;
>
> - if (cros_ec_cmd_xfer_status(ec_dev, msg) < 0)
> + if (cros_ec_cmd_xfer_status(ec_dev, msg) < 0) {
> + if (i == 0 && msg->version == 2) {
> + /* Try again with version 1 */
> + msg->version = 1;
> + msg->insize = sizeof(*resp_v1);
> + i = 0;
> + continue;
> + }
> +
> break;
> + }
>
> p += scnprintf(p, sizeof(read_buf) + read_buf - p,
> - "p%d: %s en:%.2x role:%.2x pol:%.2x\n", i,
> - resp->state, resp->enabled, resp->role,
> - resp->polarity);
> + "p%d: %s en:%.2x role:%.2x pol:%.2x", i,
> + resp_v1->state, resp_v1->enabled, resp_v1->role,
> + resp_v1->polarity);
> + if (msg->version == 2) {
> + p += scnprintf(p, sizeof(read_buf) + read_buf - p,
> + " cc:%.2x dp:%.2x ctrl:%.2x cs:%.2x gen:%.2x",
> + resp_v2->cc_state, resp_v2->dp_mode,
> + resp_v2->control_flags, resp_v2->cable_speed,
> + resp_v2->cable_gen);
> + }
> + p += scnprintf(p, sizeof(read_buf) + read_buf - p, "\n");
> }
>
> return simple_read_from_buffer(user_buf, count, ppos,
>