Re: [PATCH 1/2] ASoC: codec: wcd938x: Add switch control for selecting CTIA/OMTP Headset

[Srinivasa Rao Mandadapu]

On 2/15/2022 3:17 AM, Stephen Boyd wrote:
Thanks for your time Stephen!!!
> Quoting Srinivasa Rao Mandadapu (2022-02-12 04:24:31)
> > diff --git a/sound/soc/codecs/wcd938x.c b/sound/soc/codecs/wcd938x.c
> > index eff200a..08d16a9 100644
> > --- a/sound/soc/codecs/wcd938x.c
> > +++ b/sound/soc/codecs/wcd938x.c
> > @@ -194,6 +194,7 @@ struct wcd938x_priv {
> >          int ear_rx_path;
> >          int variant;
> >          int reset_gpio;
> > +       int us_euro_gpio;
> >          u32 micb1_mv;
> >          u32 micb2_mv;
> >          u32 micb3_mv;
> > @@ -4196,6 +4197,33 @@ static void wcd938x_dt_parse_micbias_info(struct device *dev, struct wcd938x_pri
> >                  dev_info(dev, "%s: Micbias4 DT property not found\n", __func__);
> >   }
> >
> > +static bool wcd938x_swap_gnd_mic(struct snd_soc_component *component, bool active)
> > +{
> > +       int value;
> > +
> > +       struct wcd938x_priv *wcd938x;
> > +
> > +       if (!component) {
> So component is NULL
>
> > +               dev_err(component->dev, "%s component is NULL\n", __func__);
> And now we deref component. Great NULL pointer exception Batman! Please
> test your code and remove useless checks. It makes the code harder to
> read and slows things down.
Okay. In last minute, changed from pr_err to dev_err and overlooked this 
mistake. Will remove it.
> > +               return false;
> > +       }
> > +
> > +       wcd938x = snd_soc_component_get_drvdata(component);
> > +       if (!wcd938x) {
> > +               dev_err(component->dev, "%s private data is NULL\n", __func__);
> Is this possible? I doubt it so can we just remove it?
Okay. Will remove it.
> > +               return false;
> > +       }
> > +
> > +       value = gpio_get_value(wcd938x->us_euro_gpio);
> > +
> > +       gpio_set_value(wcd938x->us_euro_gpio, !value);
> > +       /* 20us sleep required after changing the gpio state*/
> Add a space before ending comment with */
Okay.
> > +       usleep_range(20, 30);
> > +
> > +       return true;
> > +}
> > +
> > +
> >   static int wcd938x_populate_dt_data(struct wcd938x_priv *wcd938x, struct device *dev)
> >   {
> >          struct wcd_mbhc_config *cfg = &wcd938x->mbhc_cfg;
> > @@ -4208,6 +4236,16 @@ static int wcd938x_populate_dt_data(struct wcd938x_priv *wcd938x, struct device
> >                  return wcd938x->reset_gpio;
> >          }
> >
> > +       wcd938x->us_euro_gpio = of_get_named_gpio(dev->of_node, "us-euro-gpios", 0);
> Why do we need to use of GPIO APIs here? Can this driver be converted to
> use GPIO descriptors via the gpiod APIs?
Okay.  will look into it and proceed accordingly!!!
> > +       if (wcd938x->us_euro_gpio < 0) {
> > +               dev_err(dev, "Failed to get us-euro-gpios gpio: err = %d\n", wcd938x->us_euro_gpio);
> > +       } else {
> > +               cfg->swap_gnd_mic = wcd938x_swap_gnd_mic;
> > +               gpio_direction_output(wcd938x->us_euro_gpio, 0);
> > +               /* 20us sleep required after pulling the reset gpio to LOW */
> > +               usleep_range(20, 30);
> > +       }
> > +