Re: [PATCH v2] usb: typec: tcpci: pass correct rx_type to tcpm_pd_receive()

On Wed, Aug 5, 2026 at 3:33 AM Heikki Krogerus
<[email protected]> wrote:
>
> On Thu, Jul 23, 2026 at 06:46:14PM +0800, Xu Yang wrote:
> > From: Xu Yang <[email protected]>
> >
> > Previously, tcpci_irq() always passed TCPC_TX_SOP as the receive type
> > to tcpm_pd_receive(), ignoring the actual frame type reported by the
> > TCPC_RX_BUF_FRAME_TYPE register.
> >
> > Cache the TCPC_RX_DETECT register value in rx_type_mask variable. When
> > a PD messageis received, read TCPC_RX_BUF_FRAME_TYPE register and handle
> > the message only if its frame type is enabled in mask.
> >
> > The TCPC_RX_BUF_FRAME_TYPE register records the received message type,
> > which has a 1:1 mapping to enum tcpm_transmit_type.
> >
> > Fixes: fb7ff25ae433 ("usb: typec: tcpm: add discover identity support for SOP'")
> > Cc: [email protected]
> > Signed-off-by: Xu Yang <[email protected]>
>
> Acked-by: Heikki Krogerus <[email protected]>

Reviewed-by: Badhri Jagan Sridharan <[email protected]>

>
> > ---
> > Changes in v2:
> >  - add fix tag
> >  - check return value when get RX SOP type
> >  - pass all possible RX message type to tcpm_pd_receive()
> >  - cache TCPC_RX_DETECT to filter out unallowed RX messages as suggested by Badhri
> > ---
> >  drivers/usb/typec/tcpm/tcpci.c | 12 +++++++++++-
> >  include/linux/usb/tcpci.h      |  1 +
> >  2 files changed, 12 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
> > index 7ac7000b2d13..6717ac914c6a 100644
> > --- a/drivers/usb/typec/tcpm/tcpci.c
> > +++ b/drivers/usb/typec/tcpm/tcpci.c
> > @@ -38,6 +38,7 @@ struct tcpci {
> >
> >       struct regmap *regmap;
> >       unsigned int alert_mask;
> > +     unsigned int rx_type_mask;
> >
> >       bool controls_vbus;
> >
> > @@ -488,6 +489,8 @@ static int tcpci_set_pd_rx(struct tcpc_dev *tcpc, bool enable)
> >               if (tcpci->data->cable_comm_capable)
> >                       reg |= TCPC_RX_DETECT_SOP1;
> >       }
> > +
> > +     tcpci->rx_type_mask = reg;
> >       ret = regmap_write(tcpci->regmap, TCPC_RX_DETECT, reg);
> >       if (ret < 0)
> >               return ret;
> > @@ -749,6 +752,7 @@ irqreturn_t tcpci_irq(struct tcpci *tcpci)
> >       if (status & TCPC_ALERT_RX_STATUS) {
> >               struct pd_message msg;
> >               unsigned int cnt, payload_cnt;
> > +             enum tcpm_transmit_type rx_type;
> >               u16 header;
> >
> >               regmap_read(tcpci->regmap, TCPC_RX_BYTE_CNT, &cnt);
> > @@ -773,10 +777,16 @@ irqreturn_t tcpci_irq(struct tcpci *tcpci)
> >                       regmap_raw_read(tcpci->regmap, TCPC_RX_DATA,
> >                                       &msg.payload, payload_cnt);
> >
> > +             ret = regmap_read(tcpci->regmap, TCPC_RX_BUF_FRAME_TYPE, &rx_type);
> > +             if (ret)
> > +                     return ret;
> > +
> >               /* Read complete, clear RX status alert bit */
> >               tcpci_write16(tcpci, TCPC_ALERT, TCPC_ALERT_RX_STATUS);
> >
> > -             tcpm_pd_receive(tcpci->port, &msg, TCPC_TX_SOP);
> > +             rx_type &= TCPC_RX_BUF_FRAME_TYPE_MASK;
> > +             if (tcpci->rx_type_mask & BIT(rx_type))
> > +                     tcpm_pd_receive(tcpci->port, &msg, rx_type);
> >       }
> >
> >       if (tcpci->data->vbus_vsafe0v && (status & TCPC_ALERT_EXTENDED_STATUS)) {
> > diff --git a/include/linux/usb/tcpci.h b/include/linux/usb/tcpci.h
> > index f7f5cfbdef12..9b46a6bc762c 100644
> > --- a/include/linux/usb/tcpci.h
> > +++ b/include/linux/usb/tcpci.h
> > @@ -144,6 +144,7 @@
> >  #define TCPC_RX_BUF_FRAME_TYPE               0x31
> >  #define TCPC_RX_BUF_FRAME_TYPE_SOP   0
> >  #define TCPC_RX_BUF_FRAME_TYPE_SOP1  1
> > +#define TCPC_RX_BUF_FRAME_TYPE_MASK  GENMASK(2, 0)
> >  #define TCPC_RX_HDR                  0x32
> >  #define TCPC_RX_DATA                 0x34 /* through 0x4f */
> >
> > --
> > 2.34.1
>
> --
> heikki