[Intel-gfx] [PATCH 3/5] drm/i915: Write AVI infoframes for MCA LSPCON

[Shashank Sharma]

As LSPCON is a DP branch device, LSPCON vendors define
specific methods to pass AVI infoframes to the the chip.
This patch adds:
- a generic wrapper function for writing AVI infoframes for
  all LSPCON devices.
- a vendor specific function to wrire AVI infoframes into
  MCA LSPCON devices.

Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
---
 drivers/gpu/drm/i915/intel_drv.h    |  4 ++
 drivers/gpu/drm/i915/intel_hdmi.c   |  2 +
 drivers/gpu/drm/i915/intel_lspcon.c | 80 +++++++++++++++++++++++++++++++++++++
 3 files changed, 86 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a7c1c19..a468dd6 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -2037,6 +2037,10 @@ void intel_color_load_luts(struct drm_crtc_state *crtc_state);
 bool lspcon_init(struct intel_digital_port *intel_dig_port);
 void lspcon_resume(struct intel_lspcon *lspcon);
 void lspcon_wait_pcon_mode(struct intel_lspcon *lspcon);
+void lspcon_write_infoframe(struct drm_encoder *encoder,
+			     const struct intel_crtc_state *crtc_state,
+			     enum hdmi_infoframe_type type,
+			     const void *buf, ssize_t len);
 void lspcon_set_infoframes(struct drm_encoder *encoder,
 			   bool enable,
 			   const struct intel_crtc_state *crtc_state,
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 023015c..0f42718ba 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -1995,6 +1995,8 @@ void intel_infoframe_init(struct intel_digital_port *intel_dig_port)
 		intel_dig_port->infoframe_enabled = g4x_infoframe_enabled;
 	} else if (HAS_DDI(dev_priv)) {
 		if (intel_dig_port->lspcon.active) {
+			intel_dig_port->write_infoframe =
+					lspcon_write_infoframe;
 			intel_dig_port->set_infoframes = lspcon_set_infoframes;
 			intel_dig_port->infoframe_enabled =
 						lspcon_infoframe_enabled;
diff --git a/drivers/gpu/drm/i915/intel_lspcon.c b/drivers/gpu/drm/i915/intel_lspcon.c
index bb1365a..1ac4c47 100644
--- a/drivers/gpu/drm/i915/intel_lspcon.c
+++ b/drivers/gpu/drm/i915/intel_lspcon.c
@@ -31,6 +31,12 @@
 #define LSPCON_VENDOR_PARADE_OUI 0x001CF8
 #define LSPCON_VENDOR_MCA_OUI 0x0060AD
 
+/* AUX addresses to write MCA AVI IF */
+#define LSPCON_MCA_AVI_IF_WRITE_OFFSET 0x5C0
+#define LSPCON_MCA_AVI_IF_CTRL 0x5DF
+#define  LSPCON_MCA_AVI_IF_KICKOFF (1 << 0)
+#define  LSPCON_MCA_AVI_IF_HANDLED (1 << 1)
+
 static struct intel_dp *lspcon_to_intel_dp(struct intel_lspcon *lspcon)
 {
 	struct intel_digital_port *dig_port =
@@ -235,6 +241,80 @@ static void lspcon_resume_in_pcon_wa(struct intel_lspcon *lspcon)
 	DRM_DEBUG_KMS("LSPCON DP descriptor mismatch after resume\n");
 }
 
+static bool _lspcon_write_avi_infoframe_mca(struct drm_dp_aux *aux,
+					     const uint8_t *buffer, ssize_t len)
+{
+	int ret;
+	uint32_t val = 0;
+	uint16_t reg;
+	const uint8_t *data = buffer;
+
+	reg = LSPCON_MCA_AVI_IF_WRITE_OFFSET;
+	while (val < len) {
+		ret = drm_dp_dpcd_write(aux, reg, (void *)data, 1);
+		if (ret < 0) {
+			DRM_ERROR("DPCD write failed, add:0x%x\n", reg);
+			return false;
+		}
+		val++; reg++; data++;
+	}
+
+	val = 0;
+	reg = LSPCON_MCA_AVI_IF_CTRL;
+	ret = drm_dp_dpcd_read(aux, reg, &val, 1);
+	if (ret < 0) {
+		DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
+		return false;
+	}
+
+	/* Indicate LSPCON chip about infoframe, clear bit 1 and set bit 0 */
+	val &= ~LSPCON_MCA_AVI_IF_HANDLED;
+	val |= LSPCON_MCA_AVI_IF_KICKOFF;
+
+	ret = drm_dp_dpcd_write(aux, reg, &val, 1);
+	if (ret < 0) {
+		DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
+		return false;
+	}
+
+	val = 0;
+	ret = drm_dp_dpcd_read(aux, reg, &val, 1);
+	if (ret < 0) {
+		DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
+		return false;
+	}
+
+	if (val == LSPCON_MCA_AVI_IF_HANDLED)
+		DRM_DEBUG_KMS("AVI IF handled by FW\n");
+
+	return true;
+}
+
+void lspcon_write_infoframe(struct drm_encoder *encoder,
+			     const struct intel_crtc_state *crtc_state,
+			     enum hdmi_infoframe_type type,
+			     const void *frame, ssize_t len)
+{
+	bool ret = true;
+	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
+	struct intel_lspcon *lspcon = enc_to_intel_lspcon(encoder);
+
+	/* LSPCON only needs AVI IF */
+	if (type != HDMI_INFOFRAME_TYPE_AVI)
+		return;
+
+	if (lspcon->vendor == LSPCON_VENDOR_MCA)
+		ret = _lspcon_write_avi_infoframe_mca(&intel_dp->aux,
+						      frame, len);
+	if (!ret) {
+		DRM_ERROR("Failed to write AVI infoframes\n");
+		return;
+	}
+
+	DRM_DEBUG_DRIVER("AVI infoframes updated successfully\n");
+}
+
+
 void lspcon_set_infoframes(struct drm_encoder *encoder,
 			   bool enable,
 			   const struct intel_crtc_state *crtc_state,
-- 
2.7.4