On Tue, Dec 17, 2024 at 10:29:05AM +0100, Francesco Dolcini wrote:
> On Tue, Dec 17, 2024 at 05:12:08PM +0800, Xu Yang wrote:
> > With edge irq support, the ALERT event may be missed currently. The reason
> > is that ALERT_MASK register is written before devm_request_threaded_irq().
> > If ALERT event happens in this time gap, it will be missed and ALERT line
> > will not recover to high level. However, we don't meet this issue with
> > level irq. To avoid the issue, this will set ALERT_MASK register after
> > devm_request_threaded_irq() return.
> >
> > Fixes: 77e85107a771 ("usb: typec: tcpci: support edge irq")
> > Cc: stable@xxxxxxxxxxxxxxx
> > Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
> >
> > ---
> > Changes in v3:
> > - remove set_alert_mask flag
> > Changes in v2:
> > - new patch
> > ---
> > drivers/usb/typec/tcpm/tcpci.c | 17 ++++++++++++-----
> > 1 file changed, 12 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
> > index db42f4bf3632..48762508cc86 100644
> > --- a/drivers/usb/typec/tcpm/tcpci.c
> > +++ b/drivers/usb/typec/tcpm/tcpci.c
> > @@ -700,7 +700,7 @@ static int tcpci_init(struct tcpc_dev *tcpc)
> >
> > tcpci->alert_mask = reg;
> >
> > - return tcpci_write16(tcpci, TCPC_ALERT_MASK, reg);
> > + return 0;
>
> Should we set the alert mask to 0 at the beginning of tcpci_init() ?
>
> Just wondering if some bind/unbind or module reload use case would need
> it.
Maybe not needed.
tcpci = devm_kzalloc(dev, sizeof(*tcpci), GFP_KERNEL);
tcpci will be reset to all 0 when allocate the memory. So alert_mask is 0
by default.
Thanks,
Xu Yang
