[PATCH v3 2/2] drm/rockchip: cdn-dp: send audio infoframe to sink

From: Chris Zhong
Date: Wed Jul 26 2017 - 08:37:50 EST


Some DP/HDMI sink need to receive the audio infoframe to play sound,
especially some multi-channel AV receiver, they need the
channel_allocation from infoframe to config the speakers. Send the
audio infoframe via SDP will make them work properly.

Signed-off-by: Chris Zhong <zyw@xxxxxxxxxxxxxx>

---

Changes in v3: None
Changes in v2:
- According to the advice of Sean Paul and Doug
use hdmi_audio_infoframe_pack_payload to pack the buffer
define a SDP_HEADER_SIZE

drivers/gpu/drm/rockchip/cdn-dp-core.c | 20 ++++++++++++++++++++
drivers/gpu/drm/rockchip/cdn-dp-reg.c | 27 +++++++++++++++++++++++++++
drivers/gpu/drm/rockchip/cdn-dp-reg.h | 6 ++++++
include/drm/drm_dp_helper.h | 1 +
4 files changed, 54 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.c b/drivers/gpu/drm/rockchip/cdn-dp-core.c
index 9b0b058..6a4fc66 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-core.c
+++ b/drivers/gpu/drm/rockchip/cdn-dp-core.c
@@ -802,6 +802,7 @@ static int cdn_dp_audio_hw_params(struct device *dev, void *data,
.sample_rate = params->sample_rate,
.channels = params->channels,
};
+ u8 buffer[HDMI_AUDIO_INFOFRAME_SIZE + EDP_SDP_HEADER_SIZE] = { 0 };
int ret;

mutex_lock(&dp->lock);
@@ -823,6 +824,25 @@ static int cdn_dp_audio_hw_params(struct device *dev, void *data,
goto out;
}

+ /*
+ * Prepare the infoframe header to SDP header per DP 1.3 spec, Table
+ * 2-98.
+ */
+ buffer[0] = 0;
+ buffer[1] = HDMI_INFOFRAME_TYPE_AUDIO;
+ buffer[2] = 0x1b;
+ buffer[3] = 0x48;
+
+ ret = hdmi_audio_infoframe_pack_payload(&params->cea,
+ &buffer[EDP_SDP_HEADER_SIZE],
+ HDMI_AUDIO_INFOFRAME_SIZE);
+ if (ret < 0) {
+ DRM_DEV_ERROR(dev, "Failed to pack audio infoframe: %d\n", ret);
+ goto out;
+ }
+
+ cdn_dp_sdp_write(dp, 0, buffer, sizeof(buffer));
+
ret = cdn_dp_audio_config(dp, &audio);
if (!ret)
dp->audio_info = audio;
diff --git a/drivers/gpu/drm/rockchip/cdn-dp-reg.c b/drivers/gpu/drm/rockchip/cdn-dp-reg.c
index b14d211..4a818e4 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-reg.c
+++ b/drivers/gpu/drm/rockchip/cdn-dp-reg.c
@@ -286,6 +286,33 @@ int cdn_dp_dpcd_write(struct cdn_dp_device *dp, u32 addr, u8 value)
return ret;
}

+void cdn_dp_sdp_write(struct cdn_dp_device *dp, int entry_id, u8 *buf,
+ u32 buf_len)
+{
+ int idx;
+ u32 *packet = (u32 *)buf;
+ u32 num_packets = buf_len / 4;
+ u8 type;
+
+ if (buf_len < EDP_SDP_HEADER_SIZE) {
+ DRM_DEV_ERROR(dp->dev, "sdp buffer length: %d\n", buf_len);
+ return;
+ }
+
+ type = buf[1];
+
+ for (idx = 0; idx < num_packets; idx++)
+ writel(cpu_to_le32(*packet++), dp->regs + SOURCE_PIF_DATA_WR);
+
+ writel(entry_id, dp->regs + SOURCE_PIF_WR_ADDR);
+
+ writel(F_HOST_WR, dp->regs + SOURCE_PIF_WR_REQ);
+
+ writel(PIF_PKT_TYPE_VALID | F_PACKET_TYPE(type) | entry_id,
+ dp->regs + SOURCE_PIF_PKT_ALLOC_REG);
+ writel(PIF_PKT_ALLOC_WR_EN, dp->regs + SOURCE_PIF_PKT_ALLOC_WR_EN);
+}
+
int cdn_dp_load_firmware(struct cdn_dp_device *dp, const u32 *i_mem,
u32 i_size, const u32 *d_mem, u32 d_size)
{
diff --git a/drivers/gpu/drm/rockchip/cdn-dp-reg.h b/drivers/gpu/drm/rockchip/cdn-dp-reg.h
index c4bbb4a83..6ec0e81 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-reg.h
+++ b/drivers/gpu/drm/rockchip/cdn-dp-reg.h
@@ -424,6 +424,11 @@
/* Reference cycles when using lane clock as reference */
#define LANE_REF_CYC 0x8000

+#define F_HOST_WR BIT(0)
+#define PIF_PKT_ALLOC_WR_EN BIT(0)
+#define PIF_PKT_TYPE_VALID (3 << 16)
+#define F_PACKET_TYPE(x) (((x) & 0xff) << 8)
+
enum voltage_swing_level {
VOLTAGE_LEVEL_0,
VOLTAGE_LEVEL_1,
@@ -478,5 +483,6 @@ int cdn_dp_set_video_status(struct cdn_dp_device *dp, int active);
int cdn_dp_config_video(struct cdn_dp_device *dp);
int cdn_dp_audio_stop(struct cdn_dp_device *dp, struct audio_info *audio);
int cdn_dp_audio_mute(struct cdn_dp_device *dp, bool enable);
+void cdn_dp_sdp_write(struct cdn_dp_device *dp, int entry_id, u8 *buf, u32 len);
int cdn_dp_audio_config(struct cdn_dp_device *dp, struct audio_info *audio);
#endif /* _CDN_DP_REG_H */
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index b17476a..5d5dd07 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -878,6 +878,7 @@ struct edp_sdp_header {
u8 HB3; /* 7:5 reserved, 4:0 number of valid data bytes */
} __packed;

+#define EDP_SDP_HEADER_SIZE 4
#define EDP_SDP_HEADER_REVISION_MASK 0x1F
#define EDP_SDP_HEADER_VALID_PAYLOAD_BYTES 0x1F

--
2.7.4