RE: [PATCH v3 1/4] phy: core: add notify_connect and notify_disconnect callback

["Stanley Chang[昌育德]" <stanley_chang@realtek.com>]

Hi Kishon,

> -----Original Message-----
> From: Kishon Vijay Abraham I <kvijayab@amd.com>
> Sent: Tuesday, November 21, 2023 1:47 PM
> To: Stanley Chang[昌育德] <stanley_chang@realtek.com>; Greg
> Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Vinod Koul <vkoul@kernel.org>; Johan Hovold <johan@kernel.org>; Kishon
> Vijay Abraham I <kishon@kernel.org>; Geert Uytterhoeven
> <geert+renesas@glider.be>; Jinjie Ruan <ruanjinjie@huawei.com>; Rob
> Herring <robh@kernel.org>; Alan Stern <stern@rowland.harvard.edu>; Yang
> Yingliang <yangyingliang@huawei.com>; Flavio Suligoi <f.suligoi@asem.it>;
> Roy Luo <royluo@google.com>; Heikki Krogerus
> <heikki.krogerus@linux.intel.com>; Ricardo Cañuelo
> <ricardo.canuelo@collabora.com>; linux-kernel@vger.kernel.org;
> linux-phy@lists.infradead.org; linux-usb@vger.kernel.org
> Subject: Re: [PATCH v3 1/4] phy: core: add notify_connect and
> notify_disconnect callback
> 
> 
> External mail.
> 
> 
> 
> Hi Stanley,
> 
> On 11/10/2023 11:15 AM, Stanley Chang wrote:
> > In Realtek SoC, the parameter of usb phy is designed to can dynamic
> > tuning base on port status. Therefore, add a notify callback of phy
> > driver when usb connection/disconnection change.
> >
> > Signed-off-by: Stanley Chang <stanley_chang@realtek.com>
> > ---
> > v1 to v2:
> >      No change
> > v2 to v3:
> >      No change
> > ---
> >   drivers/phy/phy-core.c  | 47
> +++++++++++++++++++++++++++++++++++++++++
> >   include/linux/phy/phy.h | 18 ++++++++++++++++
> >   2 files changed, 65 insertions(+)
> >
> > diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c index
> > 96a0b1e111f3..a84ad4896b7f 100644
> > --- a/drivers/phy/phy-core.c
> > +++ b/drivers/phy/phy-core.c
> > @@ -489,6 +489,53 @@ int phy_calibrate(struct phy *phy)
> >   }
> >   EXPORT_SYMBOL_GPL(phy_calibrate);
> >
> > +/**
> > + * phy_notify_connect() - phy connect notify
> > + * @phy: the phy returned by phy_get()
> > + * @port: the port index for connect
> > + *
> > + * If phy need the get connection status, the callback can be used.
> > + * Returns: %0 if successful, a negative error code otherwise  */ int
> > +phy_notify_connect(struct phy *phy, int port) {
> > +     int ret;
> > +
> > +     if (!phy || !phy->ops->connect)
> > +             return 0;
> > +
> > +     mutex_lock(&phy->mutex);
> > +     ret = phy->ops->connect(phy, port);
> > +     mutex_unlock(&phy->mutex);
> > +
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(phy_notify_connect);
> > +
> > +/**
> > + * phy_notify_disconnect() - phy disconnect notify
> > + * @phy: the phy returned by phy_get()
> > + * @port: the port index for disconnect
> > + *
> > + * If phy need the get disconnection status, the callback can be used.
> > + *
> > + * Returns: %0 if successful, a negative error code otherwise  */ int
> > +phy_notify_disconnect(struct phy *phy, int port) {
> > +     int ret;
> > +
> > +     if (!phy || !phy->ops->disconnect)
> > +             return 0;
> > +
> > +     mutex_lock(&phy->mutex);
> > +     ret = phy->ops->disconnect(phy, port);
> > +     mutex_unlock(&phy->mutex);
> > +
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(phy_notify_disconnect);
> 
> Please use EXTCON framework for notifying connect/disconnect.

Do you mean registering notifications via extcon_register_notifier?

But there is no extcon device provided in the USB framework to notify connect and disconnect.
Therefore, I added the notification connection/disconnection based on the generic phy. 
[v3,4/4] usb: core: add phy notify connect and disconnect
https://patchwork.kernel.org/project/linux-usb/patch/20231110054738.23515-4-stanley_chang@realtek.com/

Thanks,
Stanley