Re: [PATCH 7/9] media: cros-ec-cec: Allow specifying multiple HDMI connectors

[Reka Norman]

On Mon, Aug 21, 2023 at 11:15 PM Guenter Roeck <groeck@xxxxxxxxxx> wrote:
>
> On Mon, Aug 21, 2023 at 2:12 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
> >
> > Hi Reka,
> >
> > On 14/08/2023 06:29, Reka Norman wrote:
> > > Update the cec_dmi_match_table to allow specifying multiple HDMI
> > > connectors for each device.
> > >
> > > Signed-off-by: Reka Norman <rekanorman@xxxxxxxxxxxx>
> > > ---
> > >
> > >  .../media/cec/platform/cros-ec/cros-ec-cec.c  | 47 +++++++++++--------
> > >  1 file changed, 28 insertions(+), 19 deletions(-)
> > >
> > > diff --git a/drivers/media/cec/platform/cros-ec/cros-ec-cec.c b/drivers/media/cec/platform/cros-ec/cros-ec-cec.c
> > > index c68ed5d4bda0..f2f397d9a6d8 100644
> > > --- a/drivers/media/cec/platform/cros-ec/cros-ec-cec.c
> > > +++ b/drivers/media/cec/platform/cros-ec/cros-ec-cec.c
> > > @@ -284,38 +284,41 @@ static SIMPLE_DEV_PM_OPS(cros_ec_cec_pm_ops,
> > >  #if IS_ENABLED(CONFIG_PCI) && IS_ENABLED(CONFIG_DMI)
> > >
> > >  /*
> > > - * The Firmware only handles a single CEC interface tied to a single HDMI
> > > - * connector we specify along with the DRM device name handling the HDMI output
> > > + * Specify the DRM device name handling the HDMI output and the HDMI connector
> > > + * corresponding to each CEC port. The order of connectors must match the order
> > > + * in the EC (first connector is EC port 0, ...), and the number of connectors
> > > + * must match the number of ports in the EC (which can be queried using the
> > > + * EC_CMD_CEC_PORT_COUNT host command).
> > >   */
> > >
> > >  struct cec_dmi_match {
> > >       const char *sys_vendor;
> > >       const char *product_name;
> > >       const char *devname;
> > > -     const char *conn;
> > > +     const char *conns[EC_CEC_MAX_PORTS];
> >
> > Since EC_CEC_MAX_PORTS is 16, this will waste a lot of space here.
> >
> > I would suggest creating a separate define (CEC_MAX_PORTS?) that is set
> > to 2 and is the max port that is actually used.
> >
>
> Possibly it could also be declared as const char * const ** and be
> terminated with NULL (though that would require {{ "Port B", NULL } in
> the declarations). Not sure which one is better.

I went with Guenter's suggestion. Let me know what you think.

>
> Guenter
>
> > When you get the actual number of ports from the EC you can check if
> > CEC_MAX_PORTS isn't too small and return an error if it is.
> >
> > You can use CEC_MAX_PORTS here and in the ports array of struct cros_ec_cec.
> >
> > Regards,
> >
> >         Hans
> >
> > >  };
> > >
> > >  static const struct cec_dmi_match cec_dmi_match_table[] = {
> > >       /* Google Fizz */
> > > -     { "Google", "Fizz", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Fizz", "0000:00:02.0", { "Port B" } },
> > >       /* Google Brask */
> > > -     { "Google", "Brask", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Brask", "0000:00:02.0", { "Port B" } },
> > >       /* Google Moli */
> > > -     { "Google", "Moli", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Moli", "0000:00:02.0", { "Port B" } },
> > >       /* Google Kinox */
> > > -     { "Google", "Kinox", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Kinox", "0000:00:02.0", { "Port B" } },
> > >       /* Google Kuldax */
> > > -     { "Google", "Kuldax", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Kuldax", "0000:00:02.0", { "Port B" } },
> > >       /* Google Aurash */
> > > -     { "Google", "Aurash", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Aurash", "0000:00:02.0", { "Port B" } },
> > >       /* Google Gladios */
> > > -     { "Google", "Gladios", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Gladios", "0000:00:02.0", { "Port B" } },
> > >       /* Google Lisbon */
> > > -     { "Google", "Lisbon", "0000:00:02.0", "Port B" },
> > > +     { "Google", "Lisbon", "0000:00:02.0", { "Port B" } },
> > >  };
> > >
> > >  static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev,
> > > -                                             const char **conn)
> > > +                                             const char * const **conns)
> > >  {
> > >       int i;
> > >
> > > @@ -332,7 +335,7 @@ static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev,
> > >                       if (!d)
> > >                               return ERR_PTR(-EPROBE_DEFER);
> > >                       put_device(d);
> > > -                     *conn = m->conn;
> > > +                     *conns = m->conns;
> > >                       return d;
> > >               }
> > >       }
> > > @@ -346,7 +349,7 @@ static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev,
> > >  #else
> > >
> > >  static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev,
> > > -                                             const char **conn)
> > > +                                             const char * const **conns)
> > >  {
> > >       return ERR_PTR(-ENODEV);
> > >  }
> > > @@ -388,7 +391,7 @@ static int cros_ec_cec_get_write_cmd_version(struct cros_ec_cec *cros_ec_cec)
> > >  static int cros_ec_cec_init_port(struct device *dev,
> > >                                struct cros_ec_cec *cros_ec_cec,
> > >                                int port_num, struct device *hdmi_dev,
> > > -                              const char *conn)
> > > +                              const char * const *conns)
> > >  {
> > >       struct cros_ec_cec_port *port;
> > >       int ret;
> > > @@ -406,7 +409,13 @@ static int cros_ec_cec_init_port(struct device *dev,
> > >       if (IS_ERR(port->adap))
> > >               return PTR_ERR(port->adap);
> > >
> > > -     port->notify = cec_notifier_cec_adap_register(hdmi_dev, conn,
> > > +     if (!conns[port_num]) {
> > > +             dev_err(dev, "no conn for port %d\n", port_num);
> > > +             ret = -ENODEV;
> > > +             goto out_probe_adapter;
> > > +     }
> > > +
> > > +     port->notify = cec_notifier_cec_adap_register(hdmi_dev, conns[port_num],
> > >                                                     port->adap);
> > >       if (!port->notify) {
> > >               ret = -ENOMEM;
> > > @@ -435,10 +444,10 @@ static int cros_ec_cec_probe(struct platform_device *pdev)
> > >       struct cros_ec_cec *cros_ec_cec;
> > >       struct cros_ec_cec_port *port;
> > >       struct device *hdmi_dev;
> > > -     const char *conn = NULL;
> > > +     const char * const *conns = NULL;
> > >       int ret;
> > >
> > > -     hdmi_dev = cros_ec_cec_find_hdmi_dev(&pdev->dev, &conn);
> > > +     hdmi_dev = cros_ec_cec_find_hdmi_dev(&pdev->dev, &conns);
> > >       if (IS_ERR(hdmi_dev))
> > >               return PTR_ERR(hdmi_dev);
> > >
> > > @@ -460,7 +469,7 @@ static int cros_ec_cec_probe(struct platform_device *pdev)
> > >
> > >       for (int i = 0; i < cros_ec_cec->num_ports; i++) {
> > >               ret = cros_ec_cec_init_port(&pdev->dev, cros_ec_cec, i,
> > > -                                         hdmi_dev, conn);
> > > +                                         hdmi_dev, conns);
> > >               if (ret)
> > >                       goto unregister_ports;
> > >       }
> >