[PATCH v4 2/5] drm: bridge: dw-hdmi: Report connector status using callback

From: Cheng-Yi Chiang
Date: Tue Jul 16 2019 - 07:57:54 EST


Allow codec driver register callback function for plug event.

The callback registration flow:
dw-hdmi <--- hw-hdmi-i2s-audio <--- hdmi-codec

dw-hdmi-i2s-audio implements hook_plugged_cb op
so codec driver can register the callback.

dw-hdmi exports a function dw_hdmi_set_plugged_cb so platform device
can register the callback.

When connector plug/unplug event happens, report this event using the
callback.

Make sure that audio and drm are using the single source of truth for
connector status.

Change the Kconfig of DRM_DW_HDMI so it selects SND_SOC_HDMI_CODEC.
This is for the typedef of hdmi_codec_plugged_cb to be used in dw-hdmi.c.

Signed-off-by: Cheng-Yi Chiang <cychiang@xxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/synopsys/Kconfig | 2 +-
.../drm/bridge/synopsys/dw-hdmi-i2s-audio.c | 11 +++++
drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 41 ++++++++++++++++++-
include/drm/bridge/dw_hdmi.h | 4 ++
4 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/Kconfig b/drivers/gpu/drm/bridge/synopsys/Kconfig
index 21a1be3ced0f..309da052db97 100644
--- a/drivers/gpu/drm/bridge/synopsys/Kconfig
+++ b/drivers/gpu/drm/bridge/synopsys/Kconfig
@@ -4,6 +4,7 @@ config DRM_DW_HDMI
select DRM_KMS_HELPER
select REGMAP_MMIO
select CEC_CORE if CEC_NOTIFIER
+ select SND_SOC_HDMI_CODEC

config DRM_DW_HDMI_AHB_AUDIO
tristate "Synopsys Designware AHB Audio interface"
@@ -20,7 +21,6 @@ config DRM_DW_HDMI_I2S_AUDIO
tristate "Synopsys Designware I2S Audio interface"
depends on SND_SOC
depends on DRM_DW_HDMI
- select SND_SOC_HDMI_CODEC
help
Support the I2S Audio interface which is part of the Synopsys
Designware HDMI block.
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..ca56783fae47 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 +104,21 @@ 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 device *codec_dev)
+{
+ struct dw_hdmi_i2s_audio_data *audio = data;
+ struct dw_hdmi *hdmi = audio->hdmi;
+
+ return dw_hdmi_set_plugged_cb(hdmi, fn, codec_dev);
+}
+
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..f32c66a6873d 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -185,6 +185,10 @@ struct dw_hdmi {
void (*disable_audio)(struct dw_hdmi *hdmi);

struct cec_notifier *cec_notifier;
+
+ hdmi_codec_plugged_cb plugged_cb;
+ struct device *codec_dev;
+ enum drm_connector_status last_connector_result;
};

#define HDMI_IH_PHY_STAT0_RX_SENSE \
@@ -209,6 +213,28 @@ static inline u8 hdmi_readb(struct dw_hdmi *hdmi, int offset)
return val;
}

+static void handle_plugged_change(struct dw_hdmi *hdmi, bool plugged)
+{
+ if (hdmi->plugged_cb && hdmi->codec_dev)
+ hdmi->plugged_cb(hdmi->codec_dev, plugged);
+}
+
+int dw_hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn,
+ struct device *codec_dev)
+{
+ bool plugged;
+
+ mutex_lock(&hdmi->mutex);
+ hdmi->plugged_cb = fn;
+ hdmi->codec_dev = codec_dev;
+ plugged = hdmi->last_connector_result == connector_status_connected;
+ handle_plugged_change(hdmi, plugged);
+ mutex_unlock(&hdmi->mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dw_hdmi_set_plugged_cb);
+
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 +2070,7 @@ 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 +2078,18 @@ 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);
+ handle_plugged_change(hdmi,
+ result == connector_status_connected);
+ hdmi->last_connector_result = result;
+ }
+ mutex_unlock(&hdmi->mutex);
+
+ return result;
}

static int dw_hdmi_connector_get_modes(struct drm_connector *connector)
@@ -2460,6 +2498,7 @@ __dw_hdmi_probe(struct platform_device *pdev,
hdmi->rxsense = true;
hdmi->phy_mask = (u8)~(HDMI_PHY_HPD | HDMI_PHY_RX_SENSE);
hdmi->mc_clkdis = 0x7f;
+ hdmi->last_connector_result = connector_status_disconnected;

mutex_init(&hdmi->mutex);
mutex_init(&hdmi->audio_mutex);
diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h
index b4ca970a5b75..d6c925236c55 100644
--- a/include/drm/bridge/dw_hdmi.h
+++ b/include/drm/bridge/dw_hdmi.h
@@ -6,6 +6,8 @@
#ifndef __DW_HDMI__
#define __DW_HDMI__

+#include <sound/hdmi-codec.h>
+
struct drm_connector;
struct drm_display_mode;
struct drm_encoder;
@@ -152,6 +154,8 @@ struct dw_hdmi *dw_hdmi_bind(struct platform_device *pdev,

void dw_hdmi_setup_rx_sense(struct dw_hdmi *hdmi, bool hpd, bool rx_sense);

+int dw_hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn,
+ struct device *codec_dev);
void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate);
void dw_hdmi_audio_enable(struct dw_hdmi *hdmi);
void dw_hdmi_audio_disable(struct dw_hdmi *hdmi);
--
2.22.0.510.g264f2c817a-goog