On Mon, Jan 09, 2023 at 03:19:50PM +0800, cy_huang@xxxxxxxxxxx wrote:
> From: ChiYuan Huang <cy_huang@xxxxxxxxxxx>
>
> There's the altmode re-registeration issue after data role
> swap (DR_SWAP).
>
> Comparing to USBPD 2.0, in USBPD 3.0, it loose the limit that only DFP
> can initiate the VDM command to get partner identity information.
>
> For a USBPD 3.0 UFP device, it may already get the identity information
> from its port partner before DR_SWAP. If DR_SWAP send or receive at the
> mean time, 'send_discover' flag will be raised again. It causes discover
> identify action restart while entering ready state. And after all
> discover actions are done, the 'tcpm_register_altmodes' will be called.
> If old altmode is not unregistered, this sysfs create fail can be found.
>
> In 'DR_SWAP_CHANGE_DR' state case, only DFP will unregister altmodes.
> For UFP, the original altmodes keep registered.
>
> This patch fix the logic that after DR_SWAP, 'tcpm_unregister_altmodes'
> must be called whatever the current data role is.
>
> Reviewed-by: Macpaul Lin <macpaul.lin@xxxxxxxxxxxx>
> Fixes: ae8a2ca8a221 ("usb: typec: Group all TCPCI/TCPM code together)
> Reported-by: TommyYl Chen <tommyyl.chen@xxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: ChiYuan Huang <cy_huang@xxxxxxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> ---
> Since v2:
> - Correct the mail sent from Richtek.
> - Add 'Reviewed-by' tag.
>
> Hi, Greg:
>
> Please check this one. I have strongly requested our MIS to remove the confidential string.
>
> ChiYuan Huang.
> ---
> drivers/usb/typec/tcpm/tcpm.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 904c7b4..59b366b 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4594,14 +4594,13 @@ static void run_state_machine(struct tcpm_port *port)
> tcpm_set_state(port, ready_state(port), 0);
> break;
> case DR_SWAP_CHANGE_DR:
> - if (port->data_role == TYPEC_HOST) {
> - tcpm_unregister_altmodes(port);
> + tcpm_unregister_altmodes(port);
> + if (port->data_role == TYPEC_HOST)
> tcpm_set_roles(port, true, port->pwr_role,
> TYPEC_DEVICE);
> - } else {
> + else
> tcpm_set_roles(port, true, port->pwr_role,
> TYPEC_HOST);
> - }
> tcpm_ams_finish(port);
> tcpm_set_state(port, ready_state(port), 0);
> break;
> --
> 2.7.4
--
heikki
