[PATCH i-g-t v1] tests/kms_content_protection: Add force HDCP 1.4 subtest

[Santhosh Reddy Guddati]

If a Panel supports both HDCP1.4 and HDCP2.2 versions, the kernel will
always choose the HDCP2.2 protection path and if this fails, then
HDCP1.4 will be tried.

The subtest uses debugfs support to force hdcp1.4 on the connector and
verify content protection.

Signed-off-by: Santhosh Reddy Guddati <santhosh.reddy.guddati at intel.com>
---
 tests/kms_content_protection.c | 62 ++++++++++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)

diff --git a/tests/kms_content_protection.c b/tests/kms_content_protection.c
index 6fe1edbc4..aea842bdf 100644
--- a/tests/kms_content_protection.c
+++ b/tests/kms_content_protection.c
@@ -63,6 +63,9 @@
  * Description: Test to detect the HDCP status change when we are reading the
  *              uevent sent with the corresponding connector id and property id.
  *
+ * SUBTEST: force-hdcp14
+ * Description: Test to force hdcp1.4 on the connector and verify content protection.
+ *
  * SUBTEST: %s
  * Description: Test content protection with %arg[1]
  *
@@ -102,6 +105,7 @@ struct data {
 #define CP_MEI_RELOAD				(1 << 2)
 #define CP_TYPE_CHANGE				(1 << 3)
 #define CP_UEVENT				(1 << 4)
+#define CP_FORCE14				(1 << 5)
 
 #define CP_UNDESIRED				0
 #define CP_DESIRED				1
@@ -565,6 +569,51 @@ static bool output_hdcp_capable(igt_output_t *output, int content_type)
 		return true;
 }
 
+static void enable_force_hdcp14(igt_output_t *output)
+{
+	int fd, ret;
+	char buf[MAX_SINK_HDCP_CAP_BUF_LEN];
+
+	fd = igt_debugfs_connector_dir(data.drm_fd, output->name, O_RDONLY);
+	igt_require_f(fd >= 0, "Cannot open %s debugfs\n", output->name);
+
+	ret = igt_debugfs_simple_read(fd, "i915_force_hdcp14", buf, sizeof(buf));
+	if (ret <= 0) {
+		igt_info("force_hdcp14 not supported\n");
+		close(fd);
+		return;
+	}
+
+	ret = igt_sysfs_write(fd, "i915_force_hdcp14", "1", 2);
+	igt_require_f(ret > 0, "force hdcp is not enabled\n");
+
+	ret = igt_debugfs_simple_read(fd, "i915_force_hdcp14", buf, sizeof(buf));
+	igt_assert_f(ret > 0 && strstr(buf, "yes"),
+			 "force_hdcp14 is not set to 'yes' on %s debugfs\n",
+			 output->name);
+
+	close(fd);
+}
+
+static void disable_force_hdcp14(igt_output_t *output)
+{
+	int fd, ret;
+	char buf[MAX_SINK_HDCP_CAP_BUF_LEN];
+
+	fd = igt_debugfs_connector_dir(data.drm_fd, output->name, O_RDONLY);
+	igt_require_f(fd >= 0, "Cannot open %s debugfs\n", output->name);
+
+	ret = igt_sysfs_write(fd, "i915_force_hdcp14", "0", 2);
+	igt_require_f(ret > 0, "force hdcp is not disabled\n");
+
+	ret = igt_debugfs_simple_read(fd, "i915_force_hdcp14", buf, sizeof(buf));
+	igt_assert_f(ret > 0 && strstr(buf, "no"),
+			 "i915_force_hdcp14 is not set to 'no' on %s debugfs\n",
+			 "i915_force_hdcp14");
+
+	close(fd);
+}
+
 static void
 test_fini(igt_output_t *output, enum igt_commit_style commit_style)
 {
@@ -607,9 +656,15 @@ test_content_protection(enum igt_commit_style commit_style, int content_type)
 			if (!output_hdcp_capable(output, content_type))
 				continue;
 
+			if (data.cp_tests & CP_FORCE14)
+				enable_force_hdcp14(output);
+
 			igt_dynamic_f("pipe-%s-%s", kmstest_pipe_name(pipe), output->name)
 				test_content_protection_on_output(output, pipe, commit_style, content_type);
 
+			if (data.cp_tests & CP_FORCE14)
+				disable_force_hdcp14(output);
+
 			test_fini(output, commit_style);
 			/*
 			 * Testing a output with a pipe is enough for HDCP
@@ -830,6 +885,8 @@ static void create_fbs(void)
 			    0.f, 1.f, 0.f, &data.green);
 }
 
+
+
 static const struct {
 	const char *desc;
 	const char *name;
@@ -893,6 +950,11 @@ static const struct {
 	  .cp_tests = 0,
 	  .content_type = HDCP_CONTENT_TYPE_0,
 	},
+	{ .desc = "This test forces hdcp1.4 and tests the content protection.",
+	  .name = "force-hdcp14",
+	  .cp_tests = CP_FORCE14,
+	  .content_type = HDCP_CONTENT_TYPE_0,
+	},
 };
 
 static const struct {
-- 
2.34.1