8 files changed, 161 insertions, 3 deletions
diff --git a/zephyr/shim/CMakeLists.txt b/zephyr/shim/CMakeLists.txt
new file mode 100644
index 0000000000..3add679c23
--- /dev/null
+++ b/zephyr/shim/CMakeLists.txt
@@ -0,0 +1,6 @@
+# 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.
+
+add_subdirectory("src")
+add_subdirectory("chip")
diff --git a/zephyr/shim/chip/CMakeLists.txt b/zephyr/shim/chip/CMakeLists.txt
new file mode 100644
index 0000000000..7a77febaa1
--- /dev/null
+++ b/zephyr/shim/chip/CMakeLists.txt
@@ -0,0 +1,35 @@
+# 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.
+
+# Translate Zephyr CONFIG_SOC_* values to platform/ec CHIP_* values.
+if (DEFINED CONFIG_SOC_NPCX7M6FB)
+	set(CHIP_FAMILY "NPCX7")
+	set(CHIP_VARIANT "NPCX7M6FB")
+endif()
+
+# Add compile definitions for CHIP_FAMILY_ and CHIP_VARIANT_, these are used
+# through the platform/ec code and are often used to branch header definitions
+# which are still being used. It is possible that eventually (when we also no
+# longer require the platform/ec/chip/... headers) that we'll be able to get
+# rid of this.
+zephyr_compile_definitions("CHIP_FAMILY_${CHIP_FAMILY}")
+zephyr_compile_definitions("CHIP_VARIANT_${CHIP_VARIANT}")
+
+if ("${CHIP_FAMILY}" MATCHES "^NPCX[0-9]$")
+	add_subdirectory(npcx)
+	zephyr_include_directories("${PLATFORM_EC}/chip/npcx")
+	string(TOLOWER "npcx/i2c-${CHIP_FAMILY}.c" chip_specific_i2c_impl)
+endif()
+
+# Adding chip specific i2c implementation here. These contain the specific
+# code used to implement generic information about platform/ec
+# port numbers and their properties. As such they're basically the
+# platform/ec's abstraction of devicetree and aren't worth replacing
+# quite yet until a cleaner picture of how the full migration for i2c
+# will be done.
+if (DEFINED chip_specific_i2c_impl)
+	zephyr_sources_ifdef(CONFIG_PLATFORM_EC_I2C
+		"${PLATFORM_EC}/chip/${chip_specific_i2c_impl}")
+endif()
+
diff --git a/zephyr/shim/chip/npcx/CMakeLists.txt b/zephyr/shim/chip/npcx/CMakeLists.txt
new file mode 100644
index 0000000000..377cb652b4
--- /dev/null
+++ b/zephyr/shim/chip/npcx/CMakeLists.txt
@@ -0,0 +1,5 @@
+# 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.
+
+zephyr_sources(i2c.c)
diff --git a/zephyr/shim/chip/npcx/i2c.c b/zephyr/shim/chip/npcx/i2c.c
new file mode 100644
index 0000000000..1f6fe6336d
--- /dev/null
+++ b/zephyr/shim/chip/npcx/i2c.c
@@ -0,0 +1,44 @@
+/* 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 <sys/util.h>
+
+#include "registers.h"
+#include "i2c/i2c.h"
+
+/* Shorthand for getting the device binding for a given devicetree label. */
+#define BINDING_FOR(label)                                                 \
+	device_get_binding(                                                \
+		COND_CODE_1(DT_NODE_HAS_STATUS(DT_NODELABEL(label), okay), \
+			    (DT_LABEL(DT_NODELABEL(label))), ("")))
+
+static const struct device *i2c_devices[NPCX_I2C_COUNT];
+
+static int init_device_bindings(const struct device *device)
+{
+	ARG_UNUSED(device);
+	i2c_devices[NPCX_I2C_PORT0_0] = BINDING_FOR(i2c0_0);
+	i2c_devices[NPCX_I2C_PORT1_0] = BINDING_FOR(i2c1_0);
+	i2c_devices[NPCX_I2C_PORT2_0] = BINDING_FOR(i2c2_0);
+	i2c_devices[NPCX_I2C_PORT3_0] = BINDING_FOR(i2c3_0);
+#ifdef CHIP_VARIANT_NPCX7M6G
+	i2c_devices[NPCX_I2C_PORT4_0] = BINDING_FOR(i2c4_0);
+#endif
+	i2c_devices[NPCX_I2C_PORT4_1] = BINDING_FOR(i2c4_1);
+	i2c_devices[NPCX_I2C_PORT5_0] = BINDING_FOR(i2c5_0);
+	i2c_devices[NPCX_I2C_PORT5_1] = BINDING_FOR(i2c5_1);
+	i2c_devices[NPCX_I2C_PORT6_0] = BINDING_FOR(i2c6_0);
+	i2c_devices[NPCX_I2C_PORT6_1] = BINDING_FOR(i2c6_1);
+	i2c_devices[NPCX_I2C_PORT7_0] = BINDING_FOR(i2c7_0);
+	return 0;
+}
+SYS_INIT(init_device_bindings, POST_KERNEL, 51);
+
+const struct device *i2c_get_device_for_port(const int port)
+{
+	if (port < 0 || port >= NPCX_I2C_COUNT)
+		return NULL;
+	return i2c_devices[port];
+}
diff --git a/zephyr/shim/include/config_chip.h b/zephyr/shim/include/config_chip.h
index 511d934bc5..d767b5ad90 100644
--- a/zephyr/shim/include/config_chip.h
+++ b/zephyr/shim/include/config_chip.h
@@ -51,4 +51,19 @@
 
 #endif  /* CONFIG_PLATFORM_EC_TIMER */
 
+/*
+ * Load the chip family specific header. Normally for npcx, this would be done
+ * by chip/npcx/config_chip.h but since this file is replacing that header
+ * we'll need (for now) to load it ourselves. Long term, the functions, enums,
+ * and constants in this header will be replaced by more Zephyr/devicetree
+ * specific code.
+ */
+#ifdef CHIP_FAMILY_NPCX7
+#include "config_chip-npcx7.h"
+#endif /* CHIP_FAMILY_NPCX7 */
+
+#ifdef CONFIG_PLATFORM_EC_I2C
+#define CONFIG_I2C
+#endif /* CONFIG_PLATFORM_EC_I2C */
+
 #endif  /* __CROS_EC_CONFIG_CHIP_H */
diff --git a/zephyr/shim/include/i2c/i2c.h b/zephyr/shim/include/i2c/i2c.h
new file mode 100644
index 0000000000..289f8b753e
--- /dev/null
+++ b/zephyr/shim/include/i2c/i2c.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.
+ */
+
+#ifndef ZEPHYR_CHROME_I2C_I2C_H
+#define ZEPHYR_CHROME_I2C_I2C_H
+
+#include <device.h>
+#include <devicetree.h>
+
+/**
+ * @brief Adaptation of platform/ec's port IDs which map a port/bus to a device.
+ *
+ * This function should be implemented per chip and should map the enum value
+ * defined for the chip for encoding each valid port/bus combination. For
+ * example, the npcx chip defines the port/bus combinations NPCX_I2C_PORT* under
+ * chip/npcx/registers-npcx7.h.
+ *
+ * Thus, the npcx shim should implement this function to map the enum values
+ * to the correct devicetree device.
+ *
+ * @param port The port to get the device for.
+ * @return Pointer to the device struct or {@code NULL} if none are available.
+ */
+const struct device *i2c_get_device_for_port(const int port);
+
+#endif /* ZEPHYR_CHROME_I2C_I2C_H */
diff --git a/zephyr/shim/src/CMakeLists.txt b/zephyr/shim/src/CMakeLists.txt
index 3d7f4b3099..8273ba80a5 100644
--- a/zephyr/shim/src/CMakeLists.txt
+++ b/zephyr/shim/src/CMakeLists.txt
@@ -3,9 +3,11 @@
 # found in the LICENSE file.
 
 zephyr_sources(console.c)
-zephyr_sources(util.c)
 zephyr_sources(gpio.c)
+zephyr_sources(util.c)
+
 zephyr_sources_ifdef(CONFIG_PLATFORM_EC_HOOKS hooks.c)
-zephyr_sources_ifdef(CONFIG_CROS_EC system.c)
-zephyr_sources_ifdef(CONFIG_SHIMMED_TASKS tasks.c)
 zephyr_sources_ifdef(CONFIG_PLATFORM_EC_TIMER hwtimer.c)
+zephyr_sources_ifdef(CONFIG_PLATFORM_EC_I2C   i2c.c)
+zephyr_sources_ifdef(CONFIG_CROS_EC           system.c)
+zephyr_sources_ifdef(CONFIG_SHIMMED_TASKS     tasks.c)
diff --git a/zephyr/shim/src/i2c.c b/zephyr/shim/src/i2c.c
new file mode 100644
index 0000000000..4420cec41c
--- /dev/null
+++ b/zephyr/shim/src/i2c.c
@@ -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.
+ */
+
+#include "i2c.h"
+#include "i2c/i2c.h"
+
+/*
+ * Long term we will not need these, for now they're needed to get things to
+ * build since these extern symbols are usually defined in
+ * board/${BOARD}/board.c.
+ *
+ * Since all the ports will eventually be handled by device tree. This will
+ * be removed at that point.
+ */
+const struct i2c_port_t i2c_ports[] = {};
+const unsigned int i2c_ports_used = ARRAY_SIZE(i2c_ports);
+
+int i2c_get_line_levels(int port)
+{
+	return I2C_LINE_IDLE;
+}