1 files changed, 54 insertions, 0 deletions
diff --git a/src/ec/lenovo/h8/sense.c b/src/ec/lenovo/h8/sense.c
new file mode 100644
index 0000000000..b929d7ede3
--- /dev/null
+++ b/src/ec/lenovo/h8/sense.c
@@ -0,0 +1,54 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2018 Patrick Rudolph <siro@das-labor.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <ec/acpi/ec.h>
+
+#include "h8.h"
+
+/**
+ * Return the EC sense status register state.
+ *
+ * Observations showed the sense registers are all zero until the EC populates
+ * them after some time. Likely the EC sets all bits to it's valid state at
+ * once, but there's no prove as the firmware isn't available.
+ *
+ * Wait for any register having at least one bit set.
+ * Unlikely that all register will be zero after booting has finished.
+ *
+ * @return 1 if the EC provides valid data in sense status registers
+ */
+int h8_get_sense_ready(void)
+{
+	static const u8 regs[] = { H8_STATUS0, H8_STATUS1, H8_STATUS2,
+			H8_STATUS3};
+
+	for (size_t i = 0; i < ARRAY_SIZE(regs); i++) {
+		if (ec_read(regs[i]))
+			return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * Return the state of Fn key.
+ * Only valid if h8_get_sense_ready (see above) returns true.
+ *
+ * @return 1 if the key is pressed.
+ */
+int h8_get_fn_key(void)
+{
+	return ec_read(H8_STATUS0) & H8_STATUS0_FN_KEY_DOWN;
+}