[PATCH i-g-t v1 1/2] lib/igt_whitelist: Add Hdcp Whitelist support

[Santhosh Reddy Guddati]

This introduces a mechanism to handle specific panels
like emulators/dummies that are known to face issues with certain
features like HDCP.

Tests are skipped for those outputs connected to prevent false negatives
and unnecessary debugging,

Signed-off-by: Santhosh Reddy Guddati <santhosh.reddy.guddati at intel.com>
---
 lib/igt_edid.c      | 27 ++++++++++++++++++++
 lib/igt_edid.h      |  1 +
 lib/igt_whitelist.c | 61 +++++++++++++++++++++++++++++++++++++++++++++
 lib/igt_whitelist.h | 15 +++++++++++
 lib/meson.build     |  1 +
 5 files changed, 105 insertions(+)
 create mode 100644 lib/igt_whitelist.c
 create mode 100644 lib/igt_whitelist.h

diff --git a/lib/igt_edid.c b/lib/igt_edid.c
index 80dcea112..627201c34 100644
--- a/lib/igt_edid.c
+++ b/lib/igt_edid.c
@@ -210,6 +210,33 @@ void edid_get_mfg(const struct edid *edid, char out[static 3])
 	out[2] = (edid->mfg_id[1] & 0x1F) + '@';
 }
 
+void edid_get_monitor_name(const struct edid *edid, char *name, size_t name_size)
+{
+	const struct detailed_timing *dt;
+	const struct detailed_non_pixel *np;
+	const struct detailed_data_string *ds;
+	size_t i;
+
+	assert(name_size > 0);
+	name[0] = '\0';
+
+	for (i = 0; i < DETAILED_TIMINGS_LEN; i++) {
+		dt = &edid->detailed_timings[i];
+		np = &dt->data.other_data;
+
+		if (np->type != EDID_DETAIL_MONITOR_NAME)
+			continue;
+
+		ds = &np->data.string;
+		strncpy(name, ds->str, name_size - 1);
+		name[name_size - 1] = '\0';
+		igt_debug("Monitor name: %s\n", name);
+		return;
+	}
+	igt_debug("No monitor name found in EDID\n");
+	name[0] = '\0';
+}
+
 static void edid_set_mfg(struct edid *edid, const char mfg[static 3])
 {
 	edid->mfg_id[0] = (mfg[0] - '@') << 2 | (mfg[1] - '@') >> 3;
diff --git a/lib/igt_edid.h b/lib/igt_edid.h
index 02645345f..be0ccf529 100644
--- a/lib/igt_edid.h
+++ b/lib/igt_edid.h
@@ -456,5 +456,6 @@ void *dispid_block_tiled(void *ptr,
 			 int htile, int vtile,
 			 int hsize, int vsize,
 			 const char *topology_id);
+void edid_get_monitor_name(const struct edid *edid, char *name, size_t name_size);
 
 #endif
diff --git a/lib/igt_whitelist.c b/lib/igt_whitelist.c
new file mode 100644
index 000000000..6a210406f
--- /dev/null
+++ b/lib/igt_whitelist.c
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#include <stdbool.h>
+#include <string.h>
+
+#include "drmtest.h"
+#include "igt_whitelist.h"
+
+/**
+ * Blacklist array for HDCP.
+ *
+ * This array is used to identify and handle scenarios where the test is
+ * executed on dummy monitors, such as those found on shard machines.
+ * Since these dummy monitors are not real and always the test is not consistent,
+ * the test is skipped in such cases to avoid false negatives or
+ * irrelevant test results.
+ */
+static const char *const hdcp_blacklist[] = {
+	"DPF90435", // Example monitor name
+	// Add more monitor names here as needed
+};
+
+/**
+ * is_in_blacklist - Checks if a given vendor name is present in a blacklist.
+ *
+ * @vendor_name: The name of the vendor to check for in the blacklist.
+ * @blacklist: An array of strings representing the blacklist.
+ * @blacklist_size: The number of entries in the blacklist array.
+ *
+ * Returns:
+ * true if the vendor name is found in the blacklist, false otherwise.
+ */
+static bool is_in_blacklist(const char *vendor_name,
+			    const char *const blacklist[],
+			    size_t blacklist_size)
+{
+	int i;
+
+	for (i = 0; i < blacklist_size; i++) {
+		if (strstr(blacklist[i], vendor_name) != NULL)
+			return true;
+	}
+
+	return false;
+}
+
+/**
+ * is_panel_blacklisted_hdcp - Checks if a panel vendor is blacklisted for HDCP.
+ * @vendor_name: The name of the panel vendor to check.
+ *
+ * Returns:
+ * true if the vendor is blacklisted for HDCP, false otherwise.
+ */
+bool is_panel_blacklisted_hdcp(const char *vendor_name)
+{
+	return is_in_blacklist(vendor_name, hdcp_blacklist,
+			       ARRAY_SIZE(hdcp_blacklist));
+}
diff --git a/lib/igt_whitelist.h b/lib/igt_whitelist.h
new file mode 100644
index 000000000..3ffa35db9
--- /dev/null
+++ b/lib/igt_whitelist.h
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#ifndef IGT_WHITELIST_H
+#define IGT_WHITELIST_H
+
+#include <stdbool.h>
+#include <string.h>
+
+bool is_panel_blacklisted_hdcp(const char *vendor_name);
+
+#endif
+
diff --git a/lib/meson.build b/lib/meson.build
index b58976a43..130c01336 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -112,6 +112,7 @@ lib_sources = [
 	'igt_msm.c',
 	'igt_dsc.c',
 	'igt_hook.c',
+	'igt_whitelist.c',
 	'xe/xe_gt.c',
 	'xe/xe_ioctl.c',
 	'xe/xe_mmio.c',
-- 
2.34.1