Re: [PATCH] usb: typec: tcpci: add alert.fault handling
From: Heikki Krogerus
Date: Wed Aug 12 2026 - 04:45:38 EST
On Wed, Aug 05, 2026 at 03:45:20PM +0200, Marco Felsch wrote:
> On 26-08-05, Heikki Krogerus wrote:
> > On Fri, Jul 31, 2026 at 10:34:59AM +0200, Marco Felsch wrote:
> > > Add minimal handling to clear the ALERT.Fault bit which may be set in
> > > case of an over-current or over-voltage detection. At the moment only
> > > the IRQ clear support is added since the TCPC Spec mentions that the
> > > handling of such events is vendor specific.
> > >
> > > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> > > ---
> > > drivers/usb/typec/tcpm/tcpci.c | 16 +++++++++++++++-
> > > 1 file changed, 15 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
> > > index a56e31b20c21..d2d5bf7ca618 100644
> > > --- a/drivers/usb/typec/tcpm/tcpci.c
> > > +++ b/drivers/usb/typec/tcpm/tcpci.c
> > > @@ -692,7 +692,8 @@ static int tcpci_init(struct tcpc_dev *tcpc)
> > >
> > > reg = TCPC_ALERT_TX_SUCCESS | TCPC_ALERT_TX_FAILED |
> > > TCPC_ALERT_TX_DISCARDED | TCPC_ALERT_RX_STATUS |
> > > - TCPC_ALERT_RX_HARD_RST | TCPC_ALERT_CC_STATUS;
> > > + TCPC_ALERT_RX_HARD_RST | TCPC_ALERT_CC_STATUS |
> > > + TCPC_ALERT_FAULT;
> > > if (tcpci->controls_vbus)
> > > reg |= TCPC_ALERT_POWER_STATUS;
> > > /* Enable VSAFE0V status interrupt when detecting VSAFE0V is supported */
> > > @@ -720,6 +721,19 @@ irqreturn_t tcpci_irq(struct tcpci *tcpci)
> > > irq_ret = status & tcpci->alert_mask;
> > >
> > > process_status:
> > > + /*
> > > + * Handle nested fault before clearing the alert status to not
> > > + * re-trigger a fault alert immediately again.
> > > + */
> >
> > Shouldn't that explanation in the comment be also in the commit
> > message? That sounds like the "why" part to me.
>
> I don't think so, it's just a comment for $dev that this ordering is
> important. The commit message clearly states that an over-current or
> over-voltage may trigger this.
Fair enough. Let's wait for Badhri, but FWIW:
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
--
heikki