drivers: Added fuel gauge max17048

Added support for fuel gauge max17048

Signed-off-by: Alvaro Garcia <maxpowel@gmail.com>

drivers/fuel_gauge/CMakeLists.txt

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: Apache-2.0
 
 add_subdirectory_ifdef(CONFIG_SBS_GAUGE_NEW_API		sbs_gauge)
+add_subdirectory_ifdef(CONFIG_MAX17048		max17048)
 
 zephyr_library_sources_ifdef(CONFIG_USERSPACE fuel_gauge_syscall_handlers.c)

drivers/fuel_gauge/Kconfig

@@ -19,6 +19,8 @@ config FUEL_GAUGE_INIT_PRIORITY
 	help
 	  Battery fuel gauge initialization priority.
 
+source "drivers/fuel_gauge/max17048/Kconfig"
+
 source "drivers/fuel_gauge/sbs_gauge/Kconfig"
 
 endif # FUEL_GAUGE

drivers/fuel_gauge/max17048/CMakeLists.txt

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_library()
+
+zephyr_library_sources(max17048.c)
+
+zephyr_include_directories_ifdef(CONFIG_EMUL_MAX17048 .)
+zephyr_library_sources_ifdef(CONFIG_EMUL_MAX17048 ./emul_max17048.c)

drivers/fuel_gauge/max17048/Kconfig

@@ -0,0 +1,20 @@
+# MAX17048 Li-Ion battery fuel gauge
+
+# Copyright (c) 2023, Alvaro Garcia <maxpowel@gmail.com>
+# SPDX-License-Identifier: Apache-2.0
+
+
+config MAX17048
+	bool "MAX17048 Li-Po fuel gauge"
+	default y
+	depends on DT_HAS_MAXIM_MAX17048_ENABLED
+	select I2C
+	help
+	  Enable driver for the MAX17048 fuel gauge device.
+
+config EMUL_MAX17048
+	bool "Emulate an MAX17048 fuel gague"
+	depends on EMUL
+	help
+	  It provides readings which follow a simple sequence, thus allowing
+	  test code to check that things are working as expected.

drivers/fuel_gauge/max17048/emul_max17048.c

@@ -0,0 +1,152 @@
+/*
+ * Copyright 2023, Alvaro Garcia <maxpowel@gmail.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Emulator for max17048 fuel gauge
+ */
+
+
+#define DT_DRV_COMPAT maxim_max17048
+
+
+#include <zephyr/logging/log.h>
+LOG_MODULE_REGISTER(maxim_max17048);
+
+#include <zephyr/device.h>
+#include <zephyr/drivers/emul.h>
+#include <zephyr/drivers/i2c.h>
+#include <zephyr/drivers/i2c_emul.h>
+#include <zephyr/sys/byteorder.h>
+
+#include "max17048.h"
+
+/** Static configuration for the emulator */
+struct max17048_emul_cfg {
+	/** I2C address of emulator */
+	uint16_t addr;
+};
+
+static int emul_max17048_reg_write(const struct emul *target, int reg, int val)
+{
+
+	return -EIO;
+}
+
+static int emul_max17048_reg_read(const struct emul *target, int reg, int *val)
+{
+
+	switch (reg) {
+	case REGISTER_VERSION:
+	*val = 0x1000;
+		break;
+	case REGISTER_CRATE:
+	*val = 0x4000;
+	break;
+	case REGISTER_SOC:
+	*val = 0x3525;
+		break;
+	case REGISTER_VCELL:
+	*val = 0x4387;
+		break;
+	default:
+		LOG_ERR("Unknown register 0x%x read", reg);
+		return -EIO;
+	}
+	LOG_INF("read 0x%x = 0x%x", reg, *val);
+
+	return 0;
+}
+
+static int max17048_emul_transfer_i2c(const struct emul *target, struct i2c_msg *msgs,
+				       int num_msgs, int addr)
+{
+	/* Largely copied from emul_bmi160.c */
+	struct max17048_emul_data *data;
+	unsigned int val;
+	int reg;
+	int rc;
+
+	data = target->data;
+
+	__ASSERT_NO_MSG(msgs && num_msgs);
+
+	i2c_dump_msgs_rw("emul", msgs, num_msgs, addr, false);
+	switch (num_msgs) {
+	case 2:
+		if (msgs->flags & I2C_MSG_READ) {
+			LOG_ERR("Unexpected read");
+			return -EIO;
+		}
+		if (msgs->len != 1) {
+			LOG_ERR("Unexpected msg0 length %d", msgs->len);
+			return -EIO;
+		}
+		reg = msgs->buf[0];
+
+		/* Now process the 'read' part of the message */
+		msgs++;
+		if (msgs->flags & I2C_MSG_READ) {
+			switch (msgs->len - 1) {
+			case 1:
+				rc = emul_max17048_reg_read(target, reg, &val);
+				if (rc) {
+					/* Return before writing bad value to message buffer */
+					return rc;
+				}
+
+				/* SBS uses SMBus, which sends data in little-endian format. */
+				sys_put_le16(val, msgs->buf);
+				break;
+			default:
+				LOG_ERR("Unexpected msg1 length %d", msgs->len);
+				return -EIO;
+			}
+		} else {
+			/* We write a word (2 bytes by the SBS spec) */
+			if (msgs->len != 2) {
+				LOG_ERR("Unexpected msg1 length %d", msgs->len);
+			}
+			uint16_t value = sys_get_le16(msgs->buf);
+
+			rc = emul_max17048_reg_write(target, reg, value);
+		}
+		break;
+	default:
+		LOG_ERR("Invalid number of messages: %d", num_msgs);
+		return -EIO;
+	}
+
+	return rc;
+}
+
+static const struct i2c_emul_api max17048_emul_api_i2c = {
+	.transfer = max17048_emul_transfer_i2c,
+};
+
+/**
+ * Set up a new emulator (I2C)
+ *
+ * @param emul Emulation information
+ * @param parent Device to emulate
+ * @return 0 indicating success (always)
+ */
+static int emul_max17048_init(const struct emul *target, const struct device *parent)
+{
+	ARG_UNUSED(target);
+	ARG_UNUSED(parent);
+
+	return 0;
+}
+
+/*
+ * Main instantiation macro.
+ */
+#define MAX17048_EMUL(n)                                                                          \
+	static const struct max17048_emul_cfg max17048_emul_cfg_##n = {                          \
+		.addr = DT_INST_REG_ADDR(n),                                                       \
+	};                                                                                         \
+	EMUL_DT_INST_DEFINE(n, emul_max17048_init, NULL,                  \
+			    &max17048_emul_cfg_##n, &max17048_emul_api_i2c, NULL)
+
+DT_INST_FOREACH_STATUS_OKAY(MAX17048_EMUL)