3 files changed, 37 insertions, 0 deletions
diff --git a/src/ec/purism/librem-ec/Makefile.inc b/src/ec/purism/librem-ec/Makefile.inc
index 5e2b2dfac8..464371f272 100644
--- a/src/ec/purism/librem-ec/Makefile.inc
+++ b/src/ec/purism/librem-ec/Makefile.inc
@@ -2,6 +2,7 @@
 ifeq ($(CONFIG_EC_LIBREM_EC),y)
 
 all-y += ../../system76/ec/system76_ec.c
+all-y += librem_ec.c
 smm-$(CONFIG_DEBUG_SMI) += ../../system76/ec/system76_ec.c
 
 endif
diff --git a/src/ec/purism/librem-ec/librem_ec.c b/src/ec/purism/librem-ec/librem_ec.c
new file mode 100644
index 0000000000..8298b73644
--- /dev/null
+++ b/src/ec/purism/librem-ec/librem_ec.c
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include "librem_ec.h"
+#include "../../system76/ec/system76_ec.h"
+#include <stddef.h>
+
+#define CMD_PROBE 1
+
+bool librem_ec_has_jack_detect(void)
+{
+	/* The 'flags' field in the probe command reply was added in an update.
+	   Send 4 bytes of zeroes in the "request" to zero out the field if the
+	   EC does not set it for its reply. */
+	const uint8_t request_data[4] = {0};
+	uint8_t reply_data[4] = {0};
+	bool ec_cmd_success = system76_ec_cmd(CMD_PROBE, request_data,
+		ARRAY_SIZE(request_data), reply_data, ARRAY_SIZE(reply_data));
+	if (!ec_cmd_success)
+		return false;
+	/* Byte 3 is flags, bit 0 is the jack detect flag */
+	return reply_data[3] & 0x01;
+}
diff --git a/src/ec/purism/librem-ec/librem_ec.h b/src/ec/purism/librem-ec/librem_ec.h
new file mode 100644
index 0000000000..f3a6a78fd9
--- /dev/null
+++ b/src/ec/purism/librem-ec/librem_ec.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef LIBREM_EC_H
+#define LIBREM_EC_H
+
+#include <stdbool.h>
+
+/*
+ * Check whether librem-ec has working jack detect.  This was fixed in librem-ec
+ * 1.13, so we only use the verbs with jack detect if the EC has been updated.
+ */
+bool librem_ec_has_jack_detect(void);
+
+#endif