[PATCH v5 2/6] drm: bridge/dw_hdmi: enable audio when sink device is HDMI and has audio

From: Yakir Yang
Date: Fri Jun 19 2015 - 12:24:18 EST


The original code only provide audio func when video code is a CEA mode,
but I found that No-CEA mode could also play sound when sink is HDMI mode
and has audio. So I think if sink device has the ability to play audio,
then source should enable audio support that set fc_invidconf to HDMI mode
and config n/cts rightly.

And actually we could know those information through parsing sink edid.
drm_detect_hdmi_monitor() could report whether sink is a HDMI monitor,
drm_detect_monitor_audio() could return whether sink has audio.

Signed-off-by: Yakir Yang <ykk@xxxxxxxxxxxxxx>
---
Changes in v5:
- Take Russell suggest that create "sink_has_audio" and "sink_is_hdmi" in
struct hdmi, and keep vmode's mdvi changeless.
- Config fc_invidconf to HDMI mode when sink device is HDMI monitor.

Changes in v4:
- Take Dainel suggest that introduce drm_detect_monitor_audio() to judge
whether source should config audio.

Changes in v3: None
Changes in v2: None

drivers/gpu/drm/bridge/dw_hdmi.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c
index f717a2a..417cc82 100644
--- a/drivers/gpu/drm/bridge/dw_hdmi.c
+++ b/drivers/gpu/drm/bridge/dw_hdmi.c
@@ -119,6 +119,8 @@ struct dw_hdmi {

u8 edid[HDMI_EDID_LEN];
bool cable_plugin;
+ bool sink_is_hdmi;
+ bool sink_has_audio;

bool phy_enabled;
struct drm_display_mode previous_mode;
@@ -1152,7 +1154,11 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi,
HDMI_FC_INVIDCONF_IN_I_P_INTERLACED :
HDMI_FC_INVIDCONF_IN_I_P_PROGRESSIVE;

- inv_val |= (vmode->mdvi ?
+ /*
+ * when sink device is hdmi monitor, then we can config
+ * this to hdmi_mode even if the video mode is No-CEA mode.
+ */
+ inv_val |= (hdmi->sink_is_hdmi ?
HDMI_FC_INVIDCONF_DVI_MODEZ_DVI_MODE :
HDMI_FC_INVIDCONF_DVI_MODEZ_HDMI_MODE);

@@ -1330,11 +1336,10 @@ static int dw_hdmi_setup(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
/* HDMI Initialization Step B.3 */
dw_hdmi_enable_video_path(hdmi);

- /* not for DVI mode */
- if (hdmi->hdmi_data.video_mode.mdvi) {
- dev_dbg(hdmi->dev, "%s DVI mode\n", __func__);
+ if (!hdmi->sink_has_audio) {
+ dev_info(hdmi->dev, "sink device does not support audio\n");
} else {
- dev_dbg(hdmi->dev, "%s CEA mode\n", __func__);
+ dev_dbg(hdmi->dev, "sink device support audio\n");

/* HDMI Initialization Step E - Configure audio */
hdmi_clk_regenerator_update_pixel_clock(hdmi);
@@ -1500,6 +1505,9 @@ static int dw_hdmi_connector_get_modes(struct drm_connector *connector)
dev_dbg(hdmi->dev, "got edid: width[%d] x height[%d]\n",
edid->width_cm, edid->height_cm);

+ hdmi->sink_is_hdmi = drm_detect_hdmi_monitor(edid);
+ hdmi->sink_has_audio = drm_detect_monitor_audio(edid);
+
drm_mode_connector_update_edid_property(connector, edid);
ret = drm_add_edid_modes(connector, edid);
/* Store the ELD */
--
2.1.2


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
Please read the FAQ at http://www.tux.org/lkml/