bloonchipper: Add transport and sensor detection

bloonchipper (aka hatch_fp aka dragonclaw) has a voltage divider that
can be used to select the sensor and the transport type.

Supported designs:
* Dragonclaw rev 0.2 (green with Google logo):
  go/dragonclaw-schematic-rev-0.2
* Hatch reference v3.0:
  go/hatch-schematic-rev-3.0

The selection lines are connected to ADC inputs, so a future change will
use the ADC to allow more than two transports or sensors.

BRANCH=none
BUG=b:147113851
TEST=flash dragonclaw rev 0.2 and view console output

Change-Id: If2e4b150d34cfe41477be528c70e1645043d4d82
Signed-off-by: Tom Hughes <tomhughes@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1986322
Reviewed-by: Craig Hesling <hesling@chromium.org>

board/hatch_fp/build.mk

@@ -9,6 +9,6 @@ CHIP:=stm32
 CHIP_FAMILY:=stm32f4
 CHIP_VARIANT:=stm32f412
 
-board-y=board.o
+board-y=board.o fpsensor_detect.o
 
 test-list-y=aes sha256 sha256_unrolled

board/hatch_fp/fpsensor_detect.c

@@ -0,0 +1,50 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "fpsensor_detect.h"
+#include "gpio.h"
+#include "timer.h"
+
+enum fp_sensor_type get_fp_sensor_type(void)
+{
+	enum fp_sensor_type ret;
+
+	gpio_set_level(GPIO_DIVIDER_HIGHSIDE, 1);
+	usleep(1);
+	switch (gpio_get_level(GPIO_FP_SENSOR_SEL)) {
+	case 0:
+		ret = FP_SENSOR_TYPE_ELAN;
+		break;
+	case 1:
+		ret = FP_SENSOR_TYPE_FPC;
+		break;
+	default:
+		ret = FP_SENSOR_TYPE_UNKNOWN;
+		break;
+	}
+	gpio_set_level(GPIO_DIVIDER_HIGHSIDE, 0);
+	return ret;
+}
+
+enum fp_transport_type get_fp_transport_type(void)
+{
+	enum fp_transport_type ret;
+
+	gpio_set_level(GPIO_DIVIDER_HIGHSIDE, 1);
+	usleep(1);
+	switch (gpio_get_level(GPIO_TRANSPORT_SEL)) {
+	case 0:
+		ret = FP_TRANSPORT_TYPE_UART;
+		break;
+	case 1:
+		ret = FP_TRANSPORT_TYPE_SPI;
+		break;
+	default:
+		ret = FP_TRANSPORT_TYPE_UNKNOWN;
+		break;
+	}
+	gpio_set_level(GPIO_DIVIDER_HIGHSIDE, 0);
+	return ret;
+}

board/nocturne_fp/build.mk

@@ -9,6 +9,6 @@ CHIP:=stm32
 CHIP_FAMILY:=stm32h7
 CHIP_VARIANT:=stm32h7x3
 
-board-y=board.o
+board-y=board.o fpsensor_detect.o
 
 test-list-y=aes sha256 sha256_unrolled

board/nocturne_fp/fpsensor_detect.c

@@ -0,0 +1,16 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "fpsensor_detect.h"
+
+enum fp_sensor_type get_fp_sensor_type(void)
+{
+	return FP_SENSOR_TYPE_FPC;
+}
+
+enum fp_transport_type get_fp_transport_type(void)
+{
+	return FP_TRANSPORT_TYPE_SPI;
+}

common/fpsensor/build.mk

@@ -10,3 +10,4 @@ _fpsensor_dir:=$(dir $(lastword $(MAKEFILE_LIST)))
 all-obj-$(HAS_TASK_FPSENSOR)+=$(_fpsensor_dir)fpsensor_state.o
 all-obj-$(HAS_TASK_FPSENSOR)+=$(_fpsensor_dir)fpsensor_crypto.o
 all-obj-$(HAS_TASK_FPSENSOR)+=$(_fpsensor_dir)fpsensor.o
+all-obj-$(HAS_TASK_FPSENSOR)+=$(_fpsensor_dir)fpsensor_detect_common.o

common/fpsensor/fpsensor.c

@@ -11,6 +11,7 @@
 #include "ec_commands.h"
 #include "fpsensor.h"
 #include "fpsensor_crypto.h"
+#include "fpsensor_detect.h"
 #include "fpsensor_private.h"
 #include "fpsensor_state.h"
 #include "gpio.h"
@@ -203,6 +204,11 @@ void fp_task(void)
 	gpio_config_module(MODULE_SPI_MASTER, 1);
 	spi_enable(CONFIG_SPI_FP_PORT, 1);
 
+	CPRINTS("TRANSPORT_SEL: %s",
+		fp_transport_type_to_str(get_fp_transport_type()));
+	CPRINTS("FP_SENSOR_SEL: %s",
+		fp_sensor_type_to_str(get_fp_sensor_type()));
+
 #ifdef HAVE_FP_PRIVATE_DRIVER
 	/* Reset and initialize the sensor IC */
 	fp_sensor_init();

common/fpsensor/fpsensor_detect_common.c

@@ -0,0 +1,32 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "fpsensor_detect.h"
+
+const char *fp_transport_type_to_str(enum fp_transport_type type)
+{
+	switch (type) {
+	case FP_TRANSPORT_TYPE_UNKNOWN:
+	default:
+		return "UNKNOWN";
+	case FP_TRANSPORT_TYPE_SPI:
+		return "SPI";
+	case FP_TRANSPORT_TYPE_UART:
+		return "UART";
+	}
+}
+
+const char *fp_sensor_type_to_str(enum fp_sensor_type type)
+{
+	switch (type) {
+	case FP_SENSOR_TYPE_UNKNOWN:
+	default:
+		return "UNKNOWN";
+	case FP_SENSOR_TYPE_FPC:
+		return "FPC";
+	case FP_SENSOR_TYPE_ELAN:
+		return "ELAN";
+	}
+}
+

common/mock/build.mk

@@ -5,6 +5,7 @@
 # See common/mock/README.md for more information.
 
 mock-$(HAS_MOCK_FP_SENSOR) += fp_sensor_mock.o
+mock-$(HAS_MOCK_FPSENSOR_DETECT) += fpsensor_detect_mock.o
 mock-$(HAS_MOCK_MKBP_EVENTS) += mkbp_events_mock.o
 mock-$(HAS_MOCK_ROLLBACK) += rollback_mock.o
 mock-$(HAS_MOCK_TCPC) += tcpc_mock.o

common/mock/fpsensor_detect_mock.c

@@ -0,0 +1,19 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "mock/fpsensor_detect_mock.h"
+
+struct mock_ctrl_fpsensor_detect mock_ctrl_fpsensor_detect =
+	MOCK_CTRL_DEFAULT_FPSENSOR_DETECT;
+
+enum fp_sensor_type get_fp_sensor_type(void)
+{
+	return mock_ctrl_fpsensor_detect.get_fp_sensor_type_return;
+}
+
+enum fp_transport_type get_fp_transport_type(void)
+{
+	return mock_ctrl_fpsensor_detect.get_fp_transport_type_return;
+}

driver/fingerprint/fpc/bep/fpc_private.c

@@ -8,6 +8,7 @@
 
 #include "fpc_bio_algorithm.h"
 #include "fpsensor.h"
+#include "gpio.h"
 #include "spi.h"
 #include "system.h"
 #include "util.h"
@@ -142,6 +143,12 @@ int fp_sensor_init(void)
 {
 	int rc;
 
+	/* The dragonclaw development board needs this enabled to enable the
+	 * AND gate (U10) to CS. Production boards could disable this to save
+	 * power since it's only needed for initial detection on those boards.
+	 */
+	gpio_set_level(GPIO_DIVIDER_HIGHSIDE, 1);
+
 	/* Print the binary libfpbep.a library version */
 	CPRINTS("FPC libfpbep.a %s", fp_sensor_get_version());
 

fuzz/host_command_fuzz.mocklist

@@ -5,5 +5,6 @@
 
  #define CONFIG_TEST_MOCK_LIST \
 	MOCK(FP_SENSOR)        \
+	MOCK(FPSENSOR_DETECT)  \
 	MOCK(MKBP_EVENTS)      \
 	MOCK(ROLLBACK)

include/fpsensor_detect.h

@@ -0,0 +1,28 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* Fingerprint sensor detection (transport and sensor). */
+
+#ifndef __CROS_EC_FPSENSOR_DETECT_H
+#define __CROS_EC_FPSENSOR_DETECT_H
+
+enum fp_sensor_type {
+	FP_SENSOR_TYPE_UNKNOWN = -1,
+	FP_SENSOR_TYPE_FPC,
+	FP_SENSOR_TYPE_ELAN,
+};
+
+enum fp_transport_type {
+	FP_TRANSPORT_TYPE_UNKNOWN = -1,
+	FP_TRANSPORT_TYPE_SPI,
+	FP_TRANSPORT_TYPE_UART
+};
+
+const char *fp_transport_type_to_str(enum fp_transport_type type);
+const char *fp_sensor_type_to_str(enum fp_sensor_type type);
+enum fp_sensor_type get_fp_sensor_type(void);
+enum fp_transport_type get_fp_transport_type(void);
+
+#endif /* __CROS_EC_FPSENSOR_DETECT_H */

include/mock/fpsensor_detect_mock.h

@@ -0,0 +1,23 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __MOCK_FPSENSOR_DETECT_MOCK_H
+#define __MOCK_FPSENSOR_DETECT_MOCK_H
+
+#include "fpsensor_detect.h"
+
+struct mock_ctrl_fpsensor_detect {
+	enum fp_sensor_type get_fp_sensor_type_return;
+	enum fp_transport_type get_fp_transport_type_return;
+};
+
+#define MOCK_CTRL_DEFAULT_FPSENSOR_DETECT {				\
+	.get_fp_sensor_type_return = FP_SENSOR_TYPE_UNKNOWN,		\
+	.get_fp_transport_type_return = FP_TRANSPORT_TYPE_UNKNOWN,	\
+}
+
+extern struct mock_ctrl_fpsensor_detect mock_ctrl_fpsensor_detect;
+
+#endif /* __MOCK_FPSENSOR_DETECT_MOCK_H */

test/fpsensor.mocklist

@@ -5,5 +5,6 @@
 
  #define CONFIG_TEST_MOCK_LIST \
         MOCK(FP_SENSOR)        \
+        MOCK(FPSENSOR_DETECT)  \
         MOCK(MKBP_EVENTS)      \
 	MOCK(TIMER)