zephyr: test: Add stub isl923x emulator

Add the skeleton code needed to emulate the isl923x charger.

BRANCH=none
BUG=b:201602829
TEST=zmake configure --test zephyr/test/drivers

Signed-off-by: Yuval Peress <peress@google.com>
Change-Id: Ic9af555ccd7ff6a0be2e7a0818b5e566816a0c13
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3195202
Reviewed-by: Aaron Massey <aaronmassey@google.com>
Reviewed-by: Wai-Hong Tam <waihong@google.com>

7 files changed, 116 insertions, 0 deletions

diff --git a/zephyr/dts/bindings/emul/cros,isl923x_emul.yaml b/zephyr/dts/bindings/emul/cros,isl923x_emul.yaml
new file mode 100644
index 0000000000..be8b1183a2
--- /dev/null
+++ b/zephyr/dts/bindings/emul/cros,isl923x_emul.yaml
@@ -0,0 +1,12 @@
+# Copyright 2021 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.
+
+description: ISL923X Charger emulator
+
+compatible: "cros,isl923x_emul"
+
+include: base.yaml
+properties:
+   reg:
+     required: true
diff --git a/zephyr/emul/CMakeLists.txt b/zephyr/emul/CMakeLists.txt
index 02b176b942..8bf15666ab 100644
--- a/zephyr/emul/CMakeLists.txt
+++ b/zephyr/emul/CMakeLists.txt
@@ -15,3 +15,4 @@ 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)
 zephyr_library_sources_ifdef(CONFIG_I2C_MOCK		i2c_mock.c)
+zephyr_library_sources_ifdef(CONFIG_EMUL_ISL923X	emul_isl923x.c)
diff --git a/zephyr/emul/Kconfig b/zephyr/emul/Kconfig
index 8d9c8e42ea..e47232bdd1 100644
--- a/zephyr/emul/Kconfig
+++ b/zephyr/emul/Kconfig
@@ -70,3 +70,4 @@ config EMUL_BB_RETIMER
 rsource "Kconfig.ln9310"
 rsource "Kconfig.lis2dw12"
 rsource "Kconfig.i2c_mock"
+rsource "Kconfig.isl923x"
diff --git a/zephyr/emul/Kconfig.isl923x b/zephyr/emul/Kconfig.isl923x
new file mode 100644
index 0000000000..bf124ec0a9
--- /dev/null
+++ b/zephyr/emul/Kconfig.isl923x
@@ -0,0 +1,22 @@
+# Copyright 2021 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.
+
+DT_COMPAT_ISL923X_EMUL := cros,isl923x-emul
+
+menuconfig EMUL_ISL923X
+	bool "ISL923X switchcap emulator"
+	default $(dt_compat_enabled,$(DT_COMPAT_ISL923X_EMUL))
+	depends on I2C_EMUL
+	help
+	  Enable the ISL923X emulator. This driver uses the emulated I2C bus. It
+	  is used to test the isl923x driver. Emulator API is available in
+	  zephyr/include/emul/emul_isl923x.h
+
+if EMUL_ISL923X
+
+module = ISL923X_EMUL
+module-str = isl923x_emul
+source "subsys/logging/Kconfig.template.log_config"
+
+endif # EMUL_ISL923X
diff --git a/zephyr/emul/emul_isl923x.c b/zephyr/emul/emul_isl923x.c
new file mode 100644
index 0000000000..2a76c08d74
--- /dev/null
+++ b/zephyr/emul/emul_isl923x.c
@@ -0,0 +1,64 @@
+/* Copyright 2021 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.
+ */
+
+#define DT_DRV_COMPAT cros_isl923x_emul
+
+#include <device.h>
+#include <drivers/i2c.h>
+#include <drivers/i2c_emul.h>
+#include <emul.h>
+#include <errno.h>
+#include <sys/__assert.h>
+
+#include "driver/charger/isl923x.h"
+#include "driver/charger/isl923x_public.h"
+#include "emul/emul_common_i2c.h"
+#include "emul/emul_isl923x.h"
+#include "i2c.h"
+
+#include <logging/log.h>
+LOG_MODULE_REGISTER(isl923x_emul, CONFIG_ISL923X_EMUL_LOG_LEVEL);
+
+struct isl923x_emul_data {
+	/** Common I2C data */
+	struct i2c_common_emul_data common;
+};
+
+struct isl923x_emul_cfg {
+	/** Common I2C config */
+	const struct i2c_common_emul_cfg common;
+};
+
+static int emul_isl923x_init(const struct emul *emul,
+			     const struct device *parent)
+{
+	const struct isl923x_emul_cfg *cfg = emul->cfg;
+	struct isl923x_emul_data *data = emul->data;
+
+	data->common.emul.api = &i2c_common_emul_api;
+	data->common.emul.addr = cfg->common.addr;
+	data->common.emul.parent = emul;
+	data->common.i2c = parent;
+	data->common.cfg = &cfg->common;
+	i2c_common_emul_init(&data->common);
+
+	return i2c_emul_register(parent, emul->dev_label, &data->common.emul);
+}
+
+#define INIT_ISL923X(n)                                                        \
+	static struct isl923x_emul_data isl923x_emul_data_##n = {              \
+		.common = {},                                                  \
+	};                                                                     \
+	static struct isl923x_emul_cfg isl923x_emul_cfg_##n = {                \
+	.common = {                                                            \
+		.i2c_label = DT_INST_BUS_LABEL(n),                             \
+		.dev_label = DT_INST_LABEL(n),                                 \
+		.addr = DT_INST_REG_ADDR(n),                                   \
+		},                                                             \
+	};                                                                     \
+	EMUL_DEFINE(emul_isl923x_init, DT_DRV_INST(n), &isl923x_emul_cfg_##n,  \
+		    &isl923x_emul_data_##n)
+
+DT_INST_FOREACH_STATUS_OKAY(INIT_ISL923X)
diff --git a/zephyr/include/emul/emul_isl923x.h b/zephyr/include/emul/emul_isl923x.h
new file mode 100644
index 0000000000..659b87d59e
--- /dev/null
+++ b/zephyr/include/emul/emul_isl923x.h
@@ -0,0 +1,9 @@
+/* Copyright 2021 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 ZEPHYR_INCLUDE_EMUL_EMUL_ISL923X_H_
+#define ZEPHYR_INCLUDE_EMUL_EMUL_ISL923X_H_
+
+#endif /* ZEPHYR_INCLUDE_EMUL_EMUL_ISL923X_H_ */
diff --git a/zephyr/test/drivers/overlay.dts b/zephyr/test/drivers/overlay.dts
index b211d77caa..782345a7be 100644
--- a/zephyr/test/drivers/overlay.dts
+++ b/zephyr/test/drivers/overlay.dts
@@ -541,6 +541,13 @@
 		reg = <0x84>;
 		label = "I2C_MOCK";
 	};
+
+	isl923x_emul: isl923x@9 {
+		compatible = "cros,isl923x-emul";
+		status = "okay";
+		reg = <0x9>;
+		label = "ISL923X_EMUL";
+	};
 };
 
 /* Enable all thermistors for testing */