zephyr/test: add tusb1064 usb mux emulator

Implemented tusb1064 usb mux emulator with basic i2c read/write, and
export peek reg functions.

BUG=b:229340646
TEST=none
BRANCH=none

Signed-off-by: lschyi <lschyi@google.com>
Change-Id: Ie91c216a6d1fb9ffc1decbb07c2b082b02bf8cda
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3965888
Reviewed-by: Ting Shen <phoenixshen@chromium.org>
Tested-by: Sung-Chi Li <lschyi@chromium.org>
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>
Commit-Queue: Sung-Chi Li <lschyi@chromium.org>

7 files changed, 140 insertions, 0 deletions

diff --git a/zephyr/dts/bindings/emul/zephyr,tusb1064.yaml b/zephyr/dts/bindings/emul/zephyr,tusb1064.yaml
new file mode 100644
index 0000000000..3cab1dd5a6
--- /dev/null
+++ b/zephyr/dts/bindings/emul/zephyr,tusb1064.yaml
@@ -0,0 +1,9 @@
+# Copyright 2022 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+#
+description: Zephyr TUSB1064 Emulator
+
+compatible: "zephyr,tusb1064-emul"
+
+include: "ti,tusb1064.yaml"
diff --git a/zephyr/emul/CMakeLists.txt b/zephyr/emul/CMakeLists.txt
index f8e4bae15b..377be11792 100644
--- a/zephyr/emul/CMakeLists.txt
+++ b/zephyr/emul/CMakeLists.txt
@@ -13,6 +13,7 @@ zephyr_library_sources_ifdef(CONFIG_EMUL_BMI		emul_bmi.c)
 zephyr_library_sources_ifdef(CONFIG_EMUL_BMI		emul_bmi160.c)
 zephyr_library_sources_ifdef(CONFIG_EMUL_BMI		emul_bmi260.c)
 zephyr_library_sources_ifdef(CONFIG_EMUL_TCS3400	emul_tcs3400.c)
+zephyr_library_sources_ifdef(CONFIG_EMUL_TUSB1064	emul_tusb1064.c)
 zephyr_library_sources_ifdef(CONFIG_EMUL_BB_RETIMER	emul_bb_retimer.c)
 zephyr_library_sources_ifdef(CONFIG_EMUL_LN9310		emul_ln9310.c)
 zephyr_library_sources_ifdef(CONFIG_EMUL_LIS2DW12	emul_lis2dw12.c)
diff --git a/zephyr/emul/Kconfig b/zephyr/emul/Kconfig
index 3cabd96b6f..e445e30154 100644
--- a/zephyr/emul/Kconfig
+++ b/zephyr/emul/Kconfig
@@ -60,6 +60,13 @@ config EMUL_TCS3400
 	  of proper access to reserved bits. Emulators API is available in
 	  zephyr/include/emul/emul_tcs3400.h
 
+config EMUL_TUSB1064
+	bool "TCS3400 emulator"
+	select EMUL_COMMON_I2C
+	help
+	  Enable the TUSB1064 usb mux. This driver use emulated I2C bus.
+	  Emulator API is available in zephyr/include/emul/emul_tusb1064.h.
+
 config EMUL_BB_RETIMER
 	bool "BB retimer emulator"
 	select EMUL_COMMON_I2C
diff --git a/zephyr/emul/emul_tusb1064.c b/zephyr/emul/emul_tusb1064.c
new file mode 100644
index 0000000000..4396cc5fc5
--- /dev/null
+++ b/zephyr/emul/emul_tusb1064.c
@@ -0,0 +1,108 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <zephyr/device.h>
+
+#include "driver/usb_mux/tusb1064.h"
+#include "emul/emul_common_i2c.h"
+#include "emul/emul_stub_device.h"
+#include "util.h"
+
+#define DT_DRV_COMPAT zephyr_tusb1064_emul
+
+#define TUSB1064_REG_MAX 255
+
+struct tusb1064_data {
+	struct i2c_common_emul_data common;
+	uint8_t regs[TUSB1064_REG_MAX + 1];
+};
+
+static const uint8_t default_values[TUSB1064_REG_MAX + 1] = {
+	[TUSB1064_REG_GENERAL] = 0x01,
+	[TUSB1064_REG_DP1DP3EQ_SEL] = 0x00,
+	[TUSB1064_REG_DP0DP2EQ_SEL] = 0x00,
+};
+
+void tusb1064_emul_reset_regs(const struct emul *emul)
+{
+	struct tusb1064_data *data = (struct tusb1064_data *)emul->data;
+
+	memcpy(data->regs, default_values, TUSB1064_REG_MAX + 1);
+}
+
+int tusb1064_emul_peek_reg(const struct emul *emul, int reg)
+{
+	struct tusb1064_data *data = (struct tusb1064_data *)emul->data;
+	uint8_t *regs = data->regs;
+
+	if (!IN_RANGE(reg, 0, TUSB1064_REG_MAX)) {
+		return -1;
+	}
+	return regs[reg];
+}
+
+static int tusb1064_emul_read(const struct emul *emul, int reg, uint8_t *val,
+			      int bytes, void *unused_data)
+{
+	struct tusb1064_data *data = (struct tusb1064_data *)emul->data;
+	uint8_t *regs = data->regs;
+	int pos = reg + bytes;
+
+	if (!IN_RANGE(pos, 0, TUSB1064_REG_MAX)) {
+		return -1;
+	}
+	*val = regs[pos];
+
+	return 0;
+}
+
+static int tusb1064_emul_write(const struct emul *emul, int reg, uint8_t val,
+			       int bytes, void *unused_data)
+{
+	struct tusb1064_data *data = (struct tusb1064_data *)emul->data;
+	uint8_t *regs = data->regs;
+	int pos = reg + bytes - 1;
+
+	if (!IN_RANGE(pos, 0, TUSB1064_REG_MAX) ||
+	    !IN_RANGE(val, 0, UINT8_MAX)) {
+		return -1;
+	}
+	regs[pos] = val;
+
+	return 0;
+}
+
+static int tusb1064_emul_init(const struct emul *emul,
+			      const struct device *parent)
+{
+	struct tusb1064_data *data = (struct tusb1064_data *)emul->data;
+	struct i2c_common_emul_data *common_data = &data->common;
+
+	i2c_common_emul_init(common_data);
+	i2c_common_emul_set_read_func(common_data, tusb1064_emul_read, NULL);
+	i2c_common_emul_set_write_func(common_data, tusb1064_emul_write, NULL);
+
+	tusb1064_emul_reset_regs(emul);
+
+	return 0;
+}
+
+#define INIT_TUSB1064_EMUL(n)                                          \
+	static struct i2c_common_emul_cfg common_cfg_##n;              \
+	static struct tusb1064_data tusb1064_data_##n;                 \
+	static struct i2c_common_emul_cfg common_cfg_##n = {           \
+		.dev_label = DT_NODE_FULL_NAME(DT_DRV_INST(n)),        \
+		.data = &tusb1064_data_##n.common,                     \
+		.addr = DT_INST_REG_ADDR(n)                            \
+	};                                                             \
+	static struct tusb1064_data tusb1064_data_##n = {              \
+		.common = { .cfg = &common_cfg_##n }                   \
+	};                                                             \
+	EMUL_DT_INST_DEFINE(n, tusb1064_emul_init, &tusb1064_data_##n, \
+			    &common_cfg_##n, &i2c_common_emul_api)
+
+DT_INST_FOREACH_STATUS_OKAY(INIT_TUSB1064_EMUL)
+
+DT_INST_FOREACH_STATUS_OKAY(EMUL_STUB_DEVICE);
diff --git a/zephyr/include/emul/emul_tusb1064.h b/zephyr/include/emul/emul_tusb1064.h
new file mode 100644
index 0000000000..99732e36c9
--- /dev/null
+++ b/zephyr/include/emul/emul_tusb1064.h
@@ -0,0 +1,13 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef EMUL_TUSB1064_H
+#define EMUL_TUSB1064_H
+
+#include <zephyr/drivers/emul.h>
+
+int tusb1064_emul_peek_reg(const struct emul *emul, int reg);
+
+#endif
diff --git a/zephyr/shim/include/usbc/tusb1064_usb_mux.h b/zephyr/shim/include/usbc/tusb1064_usb_mux.h
index 55dc8d4645..4dfdcaff18 100644
--- a/zephyr/shim/include/usbc/tusb1064_usb_mux.h
+++ b/zephyr/shim/include/usbc/tusb1064_usb_mux.h
@@ -9,6 +9,7 @@
 #include "driver/usb_mux/tusb1064.h"
 
 #define TUSB1064_USB_MUX_COMPAT ti_tusb1064
+#define TUSB1064_EMUL_COMPAT zephyr_tusb1064_emul
 
 #if defined(CONFIG_USB_MUX_TUSB1044)
 #define USB_MUX_CONFIG_TUSB1064(mux_id)                        \
diff --git a/zephyr/shim/include/usbc/usb_muxes.h b/zephyr/shim/include/usbc/usb_muxes.h
index d161b72b08..f94aed488d 100644
--- a/zephyr/shim/include/usbc/usb_muxes.h
+++ b/zephyr/shim/include/usbc/usb_muxes.h
@@ -36,6 +36,7 @@
 		(PS8XXX_USB_MUX_COMPAT, USB_MUX_CONFIG_TCPCI_TCPM),     \
 		(TCPCI_TCPM_USB_MUX_COMPAT, USB_MUX_CONFIG_TCPCI_TCPM), \
 		(TUSB1064_USB_MUX_COMPAT, USB_MUX_CONFIG_TUSB1064),     \
+		(TUSB1064_EMUL_COMPAT, USB_MUX_CONFIG_TUSB1064),        \
 		(VIRTUAL_USB_MUX_COMPAT, USB_MUX_CONFIG_VIRTUAL)
 
 /**