1 files changed, 149 insertions, 0 deletions
diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi_common.c b/drivers/gpu/drm/omapdrm/dss/hdmi_common.c
new file mode 100644
index 000000000..3ecde23ac
--- /dev/null
+++ b/drivers/gpu/drm/omapdrm/dss/hdmi_common.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define DSS_SUBSYS_NAME "HDMI"
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/of.h>
+
+#include "omapdss.h"
+#include "hdmi.h"
+
+int hdmi_parse_lanes_of(struct platform_device *pdev, struct device_node *ep,
+	struct hdmi_phy_data *phy)
+{
+	struct property *prop;
+	int r, len;
+
+	prop = of_find_property(ep, "lanes", &len);
+	if (prop) {
+		u32 lanes[8];
+
+		if (len / sizeof(u32) != ARRAY_SIZE(lanes)) {
+			dev_err(&pdev->dev, "bad number of lanes\n");
+			return -EINVAL;
+		}
+
+		r = of_property_read_u32_array(ep, "lanes", lanes,
+			ARRAY_SIZE(lanes));
+		if (r) {
+			dev_err(&pdev->dev, "failed to read lane data\n");
+			return r;
+		}
+
+		r = hdmi_phy_parse_lanes(phy, lanes);
+		if (r) {
+			dev_err(&pdev->dev, "failed to parse lane data\n");
+			return r;
+		}
+	} else {
+		static const u32 default_lanes[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
+
+		r = hdmi_phy_parse_lanes(phy, default_lanes);
+		if (WARN_ON(r)) {
+			dev_err(&pdev->dev, "failed to parse lane data\n");
+			return r;
+		}
+	}
+
+	return 0;
+}
+
+int hdmi_compute_acr(u32 pclk, u32 sample_freq, u32 *n, u32 *cts)
+{
+	u32 deep_color;
+	bool deep_color_correct = false;
+
+	if (n == NULL || cts == NULL)
+		return -EINVAL;
+
+	/* TODO: When implemented, query deep color mode here. */
+	deep_color = 100;
+
+	/*
+	 * When using deep color, the default N value (as in the HDMI
+	 * specification) yields to an non-integer CTS. Hence, we
+	 * modify it while keeping the restrictions described in
+	 * section 7.2.1 of the HDMI 1.4a specification.
+	 */
+	switch (sample_freq) {
+	case 32000:
+	case 48000:
+	case 96000:
+	case 192000:
+		if (deep_color == 125)
+			if (pclk == 27027000 || pclk == 74250000)
+				deep_color_correct = true;
+		if (deep_color == 150)
+			if (pclk == 27027000)
+				deep_color_correct = true;
+		break;
+	case 44100:
+	case 88200:
+	case 176400:
+		if (deep_color == 125)
+			if (pclk == 27027000)
+				deep_color_correct = true;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (deep_color_correct) {
+		switch (sample_freq) {
+		case 32000:
+			*n = 8192;
+			break;
+		case 44100:
+			*n = 12544;
+			break;
+		case 48000:
+			*n = 8192;
+			break;
+		case 88200:
+			*n = 25088;
+			break;
+		case 96000:
+			*n = 16384;
+			break;
+		case 176400:
+			*n = 50176;
+			break;
+		case 192000:
+			*n = 32768;
+			break;
+		default:
+			return -EINVAL;
+		}
+	} else {
+		switch (sample_freq) {
+		case 32000:
+			*n = 4096;
+			break;
+		case 44100:
+			*n = 6272;
+			break;
+		case 48000:
+			*n = 6144;
+			break;
+		case 88200:
+			*n = 12544;
+			break;
+		case 96000:
+			*n = 12288;
+			break;
+		case 176400:
+			*n = 25088;
+			break;
+		case 192000:
+			*n = 24576;
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+	/* Calculate CTS. See HDMI 1.3a or 1.4a specifications */
+	*cts = (pclk/1000) * (*n / 128) * deep_color / (sample_freq / 10);
+
+	return 0;
+}