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

[Chris Zhong]

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 <z...@rock-chips.com>
---

 drivers/gpu/drm/rockchip/cdn-dp-core.c | 20 ++++++++++++++++++++
 drivers/gpu/drm/rockchip/cdn-dp-reg.c  | 19 +++++++++++++++++++
 drivers/gpu/drm/rockchip/cdn-dp-reg.h  |  6 ++++++
 3 files changed, 45 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.c 
b/drivers/gpu/drm/rockchip/cdn-dp-core.c
index 9b0b058..e59ca47 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[14];
        int ret;
 
        mutex_lock(&dp->lock);
@@ -823,6 +824,25 @@ static int cdn_dp_audio_hw_params(struct device *dev,  
void *data,
                goto out;
        }
 
+       memset(buffer, 0, sizeof(buffer));
+
+       ret = hdmi_audio_infoframe_pack(&params->cea, buffer, sizeof(buffer));
+       if (ret < 0) {
+               DRM_DEV_ERROR(dev, "Failed to pack audio infoframe: %d\n", ret);
+               goto out;
+       }
+
+       /*
+        * Change 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;
+
+       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..8907db0 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-reg.c
+++ b/drivers/gpu/drm/rockchip/cdn-dp-reg.c
@@ -951,6 +951,25 @@ static void cdn_dp_audio_config_spdif(struct cdn_dp_device 
*dp)
        clk_set_rate(dp->spdif_clk, CDN_DP_SPDIF_CLK);
 }
 
+void cdn_dp_sdp_write(struct cdn_dp_device *dp, int entry_id, u8 *buf, u32 len)
+{
+       int idx;
+       u32 *packet = (u32 *)buf;
+       u32 length = len / 4;
+       u8 type = buf[1];
+
+       for (idx = 0; idx < length; 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_audio_config(struct cdn_dp_device *dp, struct audio_info *audio)
 {
        int ret;
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 */
-- 
2.6.3