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 <20190705042623.129541-3-cychiang@chromium.org> <CA+Px+wWwudeG5BLOkgcq_sJqfTxmre1O=XqU8OM6oqC966TUuQ@mail.gmail.com>
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From:   Cheng-yi Chiang <cychiang@chromium.org>
Date:   Fri, 5 Jul 2019 15:35:22 +0800
Message-ID: <CAFv8NwJBSvN-7LRX8ZMOQ4hwQ1NA9y09L0tGOyCDvsXRbADUSA@mail.gmail.com>
Subject: Re: [PATCH 2/4] drm: bridge: dw-hdmi: Report connector status using callback
To:     Tzung-Bi Shih <tzungbi@google.com>
Cc:     linux-kernel <linux-kernel@vger.kernel.org>,
        Hans Verkuil <hverkuil@xs4all.nl>,
        Mark Brown <broonie@kernel.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Takashi Iwai <tiwai@suse.com>,
        Jaroslav Kysela <perex@perex.cz>,
        Russell King <rmk+kernel@armlinux.org.uk>,
        Andrzej Hajda <a.hajda@samsung.com>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Heiko Stuebner <heiko@sntech.de>,
        Doug Anderson <dianders@chromium.org>,
        Dylan Reid <dgreid@chromium.org>, tzungbi@chromium.org,
        ALSA development <alsa-devel@alsa-project.org>,
        dri-devel@lists.freedesktop.org,
        linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org
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On Fri, Jul 5, 2019 at 3:09 PM Tzung-Bi Shih <tzungbi@google.com> wrote:
>
> On Fri, Jul 5, 2019 at 12:26 PM Cheng-Yi Chiang <cychiang@chromium.org> wrote:
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-audio.h b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-audio.h
> > index 63b5756f463b..f523c590984e 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-audio.h
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-audio.h
> > @@ -2,6 +2,8 @@
> >  #ifndef DW_HDMI_AUDIO_H
> >  #define DW_HDMI_AUDIO_H
> >
> > +#include <sound/hdmi-codec.h>
> > +
> >  struct dw_hdmi;
> >
> >  struct dw_hdmi_audio_data {
> > @@ -17,6 +19,7 @@ struct dw_hdmi_i2s_audio_data {
> >
> >         void (*write)(struct dw_hdmi *hdmi, u8 val, int offset);
> >         u8 (*read)(struct dw_hdmi *hdmi, int offset);
> > +       int (*set_plugged_cb)(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn);
> >  };
> >
> >  #endif
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c
> > index 5cbb71a866d5..7b93cf05c985 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c
> > @@ -104,10 +104,20 @@ static int dw_hdmi_i2s_get_dai_id(struct snd_soc_component *component,
> >         return -EINVAL;
> >  }
> >
> > +static int dw_hdmi_i2s_hook_plugged_cb(struct device *dev, void *data,
> > +                                      hdmi_codec_plugged_cb fn)
> > +{
> > +       struct dw_hdmi_i2s_audio_data *audio = data;
> > +       struct dw_hdmi *hdmi = audio->hdmi;
> > +
> > +       return audio->set_plugged_cb(hdmi, fn);
> > +}
> > +
> The first parameter dev could be removed.  Not used.
>
Hi Tzungbi, thanks for the review.

I am not sure about this one.
I think it depends on the DRM driver so I need to keep both..
E.g.
drivers/gpu/drm/rockchip/cdn-dp-core.c
it needs dev to access the required data.
You can check this patch:

"efc9194bcff8  ASoC: hdmi-codec: callback function will be called with
private data"

It explains that some cases use *dev, some cases use *data.

> >  static struct hdmi_codec_ops dw_hdmi_i2s_ops = {
> >         .hw_params      = dw_hdmi_i2s_hw_params,
> >         .audio_shutdown = dw_hdmi_i2s_audio_shutdown,
> >         .get_dai_id     = dw_hdmi_i2s_get_dai_id,
> > +       .hook_plugged_cb = dw_hdmi_i2s_hook_plugged_cb,
> >  };
> >
> >  static int snd_dw_hdmi_probe(struct platform_device *pdev)
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > index 045b1b13fd0e..c69a399fc7ca 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > @@ -26,6 +26,8 @@
> >  #include <drm/drm_probe_helper.h>
> >  #include <drm/bridge/dw_hdmi.h>
> >
> > +#include <sound/hdmi-codec.h>
> > +
> >  #include <uapi/linux/media-bus-format.h>
> >  #include <uapi/linux/videodev2.h>
> >
> > @@ -185,6 +187,9 @@ struct dw_hdmi {
> >         void (*disable_audio)(struct dw_hdmi *hdmi);
> >
> >         struct cec_notifier *cec_notifier;
> > +
> > +       hdmi_codec_plugged_cb plugged_cb;
> > +       enum drm_connector_status last_connector_result;
> >  };
> >
> >  #define HDMI_IH_PHY_STAT0_RX_SENSE \
> > @@ -209,6 +214,17 @@ static inline u8 hdmi_readb(struct dw_hdmi *hdmi, int offset)
> >         return val;
> >  }
> >
> > +static int hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn)
> > +{
> > +       mutex_lock(&hdmi->mutex);
> > +       hdmi->plugged_cb = fn;
> > +       if (hdmi->audio && !IS_ERR(hdmi->audio))
> I would expect if IS_ERR(hdmi->audio), then this should not be called
> (i.e. should exit somewhere earlier).
>
ACK. I should fix that.
Thanks!
> > +               fn(hdmi->audio,
> > +                  hdmi->last_connector_result == connector_status_connected);
> > +       mutex_unlock(&hdmi->mutex);
> > +       return 0;
> > +}
> > +
> >  static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg)
> >  {
> >         regmap_update_bits(hdmi->regm, reg << hdmi->reg_shift, mask, data);
> > @@ -2044,6 +2060,7 @@ dw_hdmi_connector_detect(struct drm_connector *connector, bool force)
> >  {
> >         struct dw_hdmi *hdmi = container_of(connector, struct dw_hdmi,
> >                                              connector);
> > +       enum drm_connector_status result;
> >
> >         mutex_lock(&hdmi->mutex);
> >         hdmi->force = DRM_FORCE_UNSPECIFIED;
> > @@ -2051,7 +2068,20 @@ dw_hdmi_connector_detect(struct drm_connector *connector, bool force)
> >         dw_hdmi_update_phy_mask(hdmi);
> >         mutex_unlock(&hdmi->mutex);
> >
> > -       return hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
> > +       result = hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
> > +
> > +       mutex_lock(&hdmi->mutex);
> > +       if (result != hdmi->last_connector_result) {
> > +               dev_dbg(hdmi->dev, "read_hpd result: %d", result);
> > +               if (hdmi->plugged_cb && hdmi->audio && !IS_ERR(hdmi->audio)) {
> Share the same concern above.
ACK