tests/fbcon_fbt: Enable cursor blinking

If cursor blinking is disabled no screen updates will happen and
fbcon_fbt subtests will fail, so lets enable cursor blink while
running this test and restore to the previous value when exiting it.

v4:
- renaming restore fd (Dhinakaran)
- saving previous value as char (Dhinakaran)
- skipping test if not able to open cursor blink file (Dhinakaran)

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>

2 files changed, 44 insertions, 0 deletions

diff --git a/lib/igt_sysfs.c b/lib/igt_sysfs.c
index f806f4fc..c439944d 100644
--- a/lib/igt_sysfs.c
+++ b/lib/igt_sysfs.c
@@ -610,3 +610,46 @@ void kick_snd_hda_intel(void)
 out:
 	close(fd);
 }
+
+static int fbcon_cursor_blink_fd = -1;
+static char fbcon_cursor_blink_prev_value[2];
+
+static void fbcon_cursor_blink_restore(int sig)
+{
+	write(fbcon_cursor_blink_fd, fbcon_cursor_blink_prev_value,
+	      strlen(fbcon_cursor_blink_prev_value) + 1);
+	close(fbcon_cursor_blink_fd);
+}
+
+/**
+ * fbcon_blink_enable:
+ * @enable: if true enables the fbcon cursor blinking otherwise disables it
+ *
+ * Enables or disables the cursor blinking in fbcon, it also restores the
+ * previous blinking state when exiting test.
+ *
+ */
+void fbcon_blink_enable(bool enable)
+{
+	const char *cur_blink_path = "/sys/class/graphics/fbcon/cursor_blink";
+	int fd, r;
+	char buffer[2];
+
+	fd = open(cur_blink_path, O_RDWR);
+	igt_require(fd >= 0);
+
+	/* Restore original value on exit */
+	if (fbcon_cursor_blink_fd == -1) {
+		r = read(fd, fbcon_cursor_blink_prev_value,
+			 sizeof(fbcon_cursor_blink_prev_value));
+		if (r > 0) {
+			fbcon_cursor_blink_fd = dup(fd);
+			igt_assert(fbcon_cursor_blink_fd >= 0);
+			igt_install_exit_handler(fbcon_cursor_blink_restore);
+		}
+	}
+
+	r = snprintf(buffer, sizeof(buffer), enable ? "1" : "0");
+	write(fd, buffer, r + 1);
+	close(fd);
+}
diff --git a/lib/igt_sysfs.h b/lib/igt_sysfs.h
index c12e36d1..b646df30 100644
--- a/lib/igt_sysfs.h
+++ b/lib/igt_sysfs.h
@@ -57,5 +57,6 @@ bool igt_sysfs_set_boolean(int dir, const char *attr, bool value);
 
 void bind_fbcon(bool enable);
 void kick_snd_hda_intel(void);
+void fbcon_blink_enable(bool enable);
 
 #endif /* __IGT_SYSFS_H__ */