> From: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> Sent: Wednesday, April 13, 2022 8:09 PM
> To: Linyu Yuan (QUIC) <quic_linyyuan@xxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; linux-
> usb@xxxxxxxxxxxxxxx; Jack Pham (QUIC) <quic_jackp@xxxxxxxxxxx>
> Subject: Re: [PATCH v3 2/4] usb: typec: ucsi: add a common function
> ucsi_unregister_connectors()
>
> On Wed, Apr 13, 2022 at 05:58:09PM +0800, Linyu Yuan wrote:
> > In error path of ucsi_init(), it will unregister all valid ucsi connector,
> > and samiliar operation also happen in ucsi_unregister(),
>
> Sorry but I have to confirm this: with "samiliar" you mean "the same",
> right?
Only one small difference for original code which is no cancel_work_sync() of each connector in ucsi _init(),
But in ucsi_register_port(), we get role switch after connector work initialized,
So I think it is safe to call cancel_work_sync() to connector work if role switch return -EPROBE_DEFER.
>
> > add a common function for two places.
> >
> > Signed-off-by: Linyu Yuan <quic_linyyuan@xxxxxxxxxxx>
> > ---
> > v2: improve ucsi_connector_clean(), check total number of connector.
> > v3: rename to ucsi_unregister_connectors(), suggest by maintainer
> >
> > drivers/usb/typec/ucsi/ucsi.c | 51 ++++++++++++++++++++++++-----------
> --------
> > 1 file changed, 28 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> > index 77ac0b7..af9a2a1 100644
> > --- a/drivers/usb/typec/ucsi/ucsi.c
> > +++ b/drivers/usb/typec/ucsi/ucsi.c
> > @@ -1187,6 +1187,32 @@ static int ucsi_register_port(struct ucsi *ucsi, int
> index)
> > return ret;
> > }
> >
> > +static void ucsi_unregister_connectors(struct ucsi *ucsi)
> > +{
> > + struct ucsi_connector *con;
> > + int i;
> > +
> > + if (!ucsi->connector)
> > + return;
>
> Can that actually ever happen?
Consider a case, ucsi_init() failed, we will call ucsi_unregister_connectors() to free all connectors,
After that the UCSI implementation like ucsi_acpi call ucsi_unregister() again,
It should not unregister connectors again.
>
> > + for (i = 0; i < ucsi->cap.num_connectors; i++) {
> > + con = &ucsi->connector[i];
> > + if (!con->port)
> > + break;
> > +
> > + cancel_work_sync(&con->work);
> > + ucsi_unregister_partner(con);
> > + ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
> > + ucsi_unregister_port_psy(con);
> > + if (con->wq)
> > + destroy_workqueue(con->wq);
> > + typec_unregister_port(con->port);
> > + }
> > +
> > + kfree(ucsi->connector);
> > + ucsi->connector = NULL;
> > +}
>
> Another way of doing this would be to just remove a single connector
> in the function, and leave the loops to the callers.
>
> static void ucsi_unregister_connector(struct ucsi_connector *con)
> {
> cancel_work_sync(&con->work);
> ucsi_unregister_partner(con);
> ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
> ucsi_unregister_port_psy(con);
> if (con->wq)
> destroy_workqueue(con->wq);
> typec_unregister_port(con->port);
> }
>
> I wonder would it actually be a bit more clearer to do it like that...
> I'll leave the decision to you.
I will keep it,
There will be no duplicate loop entry in two function, a little lazy.
>
> > /**
> > * ucsi_init - Initialize UCSI interface
> > * @ucsi: UCSI to be initialized
> > @@ -1195,7 +1221,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int
> index)
> > */
> > static int ucsi_init(struct ucsi *ucsi)
> > {
> > - struct ucsi_connector *con;
> > u64 command;
> > int ret;
> > int i;
> > @@ -1250,15 +1275,7 @@ static int ucsi_init(struct ucsi *ucsi)
> > return 0;
> >
> > err_unregister:
> > - for (con = ucsi->connector; con->port; con++) {
> > - ucsi_unregister_partner(con);
> > - ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
> > - ucsi_unregister_port_psy(con);
> > - if (con->wq)
> > - destroy_workqueue(con->wq);
> > - typec_unregister_port(con->port);
> > - con->port = NULL;
> > - }
> > + ucsi_unregister_connectors(ucsi);
> >
> > err_reset:
> > memset(&ucsi->cap, 0, sizeof(ucsi->cap));
> > @@ -1364,7 +1381,6 @@ EXPORT_SYMBOL_GPL(ucsi_register);
> > void ucsi_unregister(struct ucsi *ucsi)
> > {
> > u64 cmd = UCSI_SET_NOTIFICATION_ENABLE;
> > - int i;
> >
> > /* Make sure that we are not in the middle of driver initialization */
> > cancel_work_sync(&ucsi->work);
> > @@ -1372,18 +1388,7 @@ void ucsi_unregister(struct ucsi *ucsi)
> > /* Disable notifications */
> > ucsi->ops->async_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
> >
> > - for (i = 0; i < ucsi->cap.num_connectors; i++) {
> > - cancel_work_sync(&ucsi->connector[i].work);
> > - ucsi_unregister_partner(&ucsi->connector[i]);
> > - ucsi_unregister_altmodes(&ucsi->connector[i],
> > - UCSI_RECIPIENT_CON);
> > - ucsi_unregister_port_psy(&ucsi->connector[i]);
> > - if (ucsi->connector[i].wq)
> > - destroy_workqueue(ucsi->connector[i].wq);
> > - typec_unregister_port(ucsi->connector[i].port);
> > - }
> > -
> > - kfree(ucsi->connector);
> > + ucsi_unregister_connectors(ucsi);
> > }
> > EXPORT_SYMBOL_GPL(ucsi_unregister);
>
> thanks,
>
> --
> heikki
