[igt-dev] [PATCH i-g-t] tests/i915/i915_pm_backlight: Add new subtest to validate dual panel backlight

[Nidhi Gupta <nidhi1.gupta@intel.com>]

Since driver can now support multiple eDPs and Debugfs structure for
backlight changed per connector the test should then iterate through
all eDP connectors.

Signed-off-by: Nidhi Gupta <nidhi1.gupta@intel.com>
---
 tests/i915/i915_pm_backlight.c | 70 +++++++++++++++++++---------------
 1 file changed, 39 insertions(+), 31 deletions(-)

diff --git a/tests/i915/i915_pm_backlight.c b/tests/i915/i915_pm_backlight.c
index cafae7f7..1532193b 100644
--- a/tests/i915/i915_pm_backlight.c
+++ b/tests/i915/i915_pm_backlight.c
@@ -37,25 +37,26 @@
 
 struct context {
 	int max;
+	const char *path;
 };
 
 
 #define TOLERANCE 5 /* percent */
-#define BACKLIGHT_PATH "/sys/class/backlight/intel_backlight"
+#define BACKLIGHT_PATH "/sys/class/backlight"
 
 #define FADESTEPS 10
 #define FADESPEED 100 /* milliseconds between steps */
 
 IGT_TEST_DESCRIPTION("Basic backlight sysfs test");
 
-static int backlight_read(int *result, const char *fname)
+static int backlight_read(int *result, const char *fname, struct context *context)
 {
 	int fd;
 	char full[PATH_MAX];
 	char dst[64];
 	int r, e;
 
-	igt_assert(snprintf(full, PATH_MAX, "%s/%s", BACKLIGHT_PATH, fname) < PATH_MAX);
+	igt_assert(snprintf(full, PATH_MAX, "%s/%s/%s", BACKLIGHT_PATH, context->path, fname) < PATH_MAX);
 
 	fd = open(full, O_RDONLY);
 	if (fd == -1)
@@ -73,14 +74,14 @@ static int backlight_read(int *result, const char *fname)
 	return errno;
 }
 
-static int backlight_write(int value, const char *fname)
+static int backlight_write(int value, const char *fname, struct context *context)
 {
 	int fd;
 	char full[PATH_MAX];
 	char src[64];
 	int len;
 
-	igt_assert(snprintf(full, PATH_MAX, "%s/%s", BACKLIGHT_PATH, fname) < PATH_MAX);
+	igt_assert(snprintf(full, PATH_MAX, "%s/%s/%s", BACKLIGHT_PATH, context->path, fname) < PATH_MAX);
 	fd = open(full, O_WRONLY);
 	if (fd == -1)
 		return -errno;
@@ -100,12 +101,12 @@ static void test_and_verify(struct context *context, int val)
 	const int tolerance = val * TOLERANCE / 100;
 	int result;
 
-	igt_assert_eq(backlight_write(val, "brightness"), 0);
-	igt_assert_eq(backlight_read(&result, "brightness"), 0);
+	igt_assert_eq(backlight_write(val, "brightness", context), 0);
+	igt_assert_eq(backlight_read(&result, "brightness", context), 0);
 	/* Check that the exact value sticks */
 	igt_assert_eq(result, val);
 
-	igt_assert_eq(backlight_read(&result, "actual_brightness"), 0);
+	igt_assert_eq(backlight_read(&result, "actual_brightness", context), 0);
 	/* Some rounding may happen depending on hw */
 	igt_assert_f(result >= max(0, val - tolerance) &&
 		     result <= min(context->max, val + tolerance),
@@ -124,16 +125,16 @@ static void test_bad_brightness(struct context *context)
 {
 	int val;
 	/* First write some sane value */
-	backlight_write(context->max / 2, "brightness");
+	backlight_write(context->max / 2, "brightness", context);
 	/* Writing invalid values should fail and not change the value */
-	igt_assert_lt(backlight_write(-1, "brightness"), 0);
-	backlight_read(&val, "brightness");
+	igt_assert_lt(backlight_write(-1, "brightness", context), 0);
+	backlight_read(&val, "brightness", context);
 	igt_assert_eq(val, context->max / 2);
-	igt_assert_lt(backlight_write(context->max + 1, "brightness"), 0);
-	backlight_read(&val, "brightness");
+	igt_assert_lt(backlight_write(context->max + 1, "brightness", context), 0);
+	backlight_read(&val, "brightness", context);
 	igt_assert_eq(val, context->max / 2);
-	igt_assert_lt(backlight_write(INT_MAX, "brightness"), 0);
-	backlight_read(&val, "brightness");
+	igt_assert_lt(backlight_write(INT_MAX, "brightness", context), 0);
+	backlight_read(&val, "brightness", context);
 	igt_assert_eq(val, context->max / 2);
 }
 
@@ -186,6 +187,7 @@ igt_main
 	igt_display_t display;
 	igt_output_t *output;
 	struct igt_fb fb;
+	char paths[][50] = { "intel_backlight", "card0-eDP-2-backlight" };
 
 	igt_fixture {
 		enum pipe pipe;
@@ -203,11 +205,14 @@ igt_main
 		igt_display_require(&display, drm_open_driver(DRIVER_INTEL));
 
 		/* Get the max value and skip the whole test if sysfs interface not available */
-		igt_skip_on(backlight_read(&old, "brightness"));
-		igt_assert(backlight_read(&context.max, "max_brightness") > -1);
+		for (size_t i = 0; i < sizeof(paths) / sizeof(paths[0]); i++) {
+			context.path = paths[i];
+			igt_skip_on(backlight_read(&old, "brightness", &context));
+			igt_assert(backlight_read(&context.max, "max_brightness", &context) > -1);
+		}
 
 		/* should be ../../cardX-$output */
-		igt_assert_lt(12, readlink(BACKLIGHT_PATH "/device", full_name, sizeof(full_name) - 1));
+		igt_assert_lt(12, readlink(BACKLIGHT_PATH "/intel_backlight/device", full_name, sizeof(full_name) - 1));
 		name = basename(full_name);
 
 		for_each_pipe_with_valid_output(&display, pipe, output) {
@@ -234,22 +239,25 @@ igt_main
 		igt_display_commit2(&display, display.is_atomic ? COMMIT_ATOMIC : COMMIT_LEGACY);
 		igt_pm_enable_sata_link_power_management();
 	}
+	for (size_t j = 0; j < sizeof(paths) / sizeof(paths[0]); j++) {
+		context.path = paths[j];
+
+		igt_subtest("basic-brightness")
+			test_brightness(&context);
+		igt_subtest("bad-brightness")
+			test_bad_brightness(&context);
+		igt_subtest("fade")
+			test_fade(&context);
+		igt_subtest("fade_with_dpms")
+			test_fade_with_dpms(&context, output);
+		igt_subtest("fade_with_suspend")
+			test_fade_with_suspend(&context, output);
 
-	igt_subtest("basic-brightness")
-		test_brightness(&context);
-	igt_subtest("bad-brightness")
-		test_bad_brightness(&context);
-	igt_subtest("fade")
-		test_fade(&context);
-	igt_subtest("fade_with_dpms")
-		test_fade_with_dpms(&context, output);
-	igt_subtest("fade_with_suspend")
-		test_fade_with_suspend(&context, output);
-
-	igt_fixture {
 		/* Restore old brightness */
-		backlight_write(old, "brightness");
+                backlight_write(old, "brightness", &context);
+	}
 
+	igt_fixture {
 		igt_display_fini(&display);
 		igt_remove_fb(display.drm_fd, &fb);
 		igt_pm_restore_sata_link_power_management();
-- 
2.36.0