Re: [PATCH] platform/chrome: cros_ec_typec: Poll for role swap completion

[Tzung-Bi Shih <tzungbi@kernel.org>]

On Wed, Sep 23, 2026 at 07:44:19PM +0200, Marek Maslanka wrote:
> @@ -104,27 +127,41 @@ static int cros_typec_perform_role_swap(struct typec_port *tc_port, int target_r
>  	if (ret < 0)
>  		return ret;
>  
> -	switch (swap_type) {
> -	case USB_PD_CTRL_SWAP_DATA:
> -		role = resp.role & PD_CTRL_RESP_ROLE_DATA ? TYPEC_HOST : TYPEC_DEVICE;
> -		if (role != target_role) {
> -			dev_err(data->dev, "Data role swap failed despite EC returning success\n");
> -			return -EIO;
> +	/*
> +	 * Depending on the EC USB-C stack (TCPMv2 vs PDC), EC_CMD_USB_PD_CONTROL
> +	 * may either block until the swap completes or queue the request
> +	 * asynchronously and return the pre-swap role. Poll until the target
> +	 * role is reached while connected, or until the timeout expires.
> +	 */
> +	req.swap = USB_PD_CTRL_SWAP_NONE;
> +	end = jiffies + msecs_to_jiffies(ROLE_SWAP_TIMEOUT_MS);
> +	for (;;) {
> +		if ((resp.enabled & PD_CTRL_RESP_ENABLED_CONNECTED) &&

Shouldn't PD_CTRL_RESP_ENABLED_CONNECTED remain set during the entire poll?

> +		    cros_typec_resp_to_role(&resp, swap_type) == target_role)
> +			break;
> +
> +		if (time_after_eq(jiffies, end)) {
> +			if (!(resp.enabled & PD_CTRL_RESP_ENABLED_CONNECTED)) {
> +				dev_err(data->dev, "Port disconnected during role swap\n");
> +				return -ENOTCONN;

Same here: if PD_CTRL_RESP_ENABLED_CONNECTED isn't set in the loop, should
it return -ENOTCONN early (i.e., out of this if-block)?