feat(st-pmic): add STPMIC2 driver

The STPMIC2 embeds 15 regulators with various
properties, and is designed to supply the STM32MP2
SOC. This driver handles a minimal set of feature
to handle the boot of a board.

Signed-off-by: Pascal Paillet <p.paillet@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Signed-off-by: Maxime Méré <maxime.mere@foss.st.com>
Change-Id: Ibe0cacf8aec2871eb9a86ec16cbbd18d3745fe9e
diff --git a/drivers/st/pmic/stm32mp_pmic2.c b/drivers/st/pmic/stm32mp_pmic2.c
new file mode 100644
index 0000000..c19d36a
--- /dev/null
+++ b/drivers/st/pmic/stm32mp_pmic2.c
@@ -0,0 +1,499 @@
+/*
+ * Copyright (C) 2024, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+
+#include <common/debug.h>
+#include <drivers/delay_timer.h>
+#include <drivers/st/regulator.h>
+#include <drivers/st/stm32_i2c.h>
+#include <drivers/st/stm32mp_pmic2.h>
+#include <drivers/st/stpmic2.h>
+#include <lib/mmio.h>
+#include <lib/spinlock.h>
+#include <lib/utils_def.h>
+#include <libfdt.h>
+
+#include <platform_def.h>
+
+#define PMIC_NODE_NOT_FOUND	1
+
+struct regul_handle_s {
+	const uint32_t id;
+	uint16_t bypass_mv;
+};
+
+static struct pmic_handle_s pmic2_handle;
+static struct i2c_handle_s i2c_handle;
+
+/* This driver is monoinstance */
+static struct pmic_handle_s *pmic2;
+
+static int dt_get_pmic_node(void *fdt)
+{
+	static int node = -FDT_ERR_BADOFFSET;
+
+	if (node == -FDT_ERR_BADOFFSET) {
+		node = fdt_node_offset_by_compatible(fdt, -1, "st,stpmic2");
+	}
+
+	return node;
+}
+
+int dt_pmic_status(void)
+{
+	static int status = -FDT_ERR_BADVALUE;
+	int node;
+	void *fdt;
+
+	if (status != -FDT_ERR_BADVALUE) {
+		return status;
+	}
+
+	if (fdt_get_address(&fdt) == 0) {
+		return -ENOENT;
+	}
+
+	node = dt_get_pmic_node(fdt);
+	if (node <= 0) {
+		status = -FDT_ERR_NOTFOUND;
+
+		return status;
+	}
+
+	status = DT_SECURE;
+
+	return status;
+}
+
+/*
+ * Get PMIC and its I2C bus configuration from the device tree.
+ * Return 0 on success, negative on error, 1 if no PMIC node is defined.
+ */
+static int dt_pmic2_i2c_config(struct dt_node_info *i2c_info,
+			       struct stm32_i2c_init_s *init,
+			       uint32_t *i2c_addr)
+{
+	static int i2c_node = -FDT_ERR_NOTFOUND;
+	void *fdt;
+
+	if (fdt_get_address(&fdt) == 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	if (i2c_node == -FDT_ERR_NOTFOUND) {
+		int pmic_node;
+		const fdt32_t *cuint;
+
+		pmic_node = dt_get_pmic_node(fdt);
+		if (pmic_node < 0) {
+			return PMIC_NODE_NOT_FOUND;
+		}
+
+		cuint = fdt_getprop(fdt, pmic_node, "reg", NULL);
+		if (cuint == NULL) {
+			return -FDT_ERR_NOTFOUND;
+		}
+
+		*i2c_addr = fdt32_to_cpu(*cuint) << 1;
+		if (*i2c_addr > UINT16_MAX) {
+			return -FDT_ERR_BADVALUE;
+		}
+
+		i2c_node = fdt_parent_offset(fdt, pmic_node);
+		if (i2c_node < 0) {
+			return -FDT_ERR_NOTFOUND;
+		}
+	}
+
+	dt_fill_device_info(i2c_info, i2c_node);
+	if (i2c_info->base == 0U) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	i2c_info->status = DT_SECURE;
+
+	return stm32_i2c_get_setup_from_fdt(fdt, i2c_node, init);
+}
+
+bool initialize_pmic_i2c(void)
+{
+	int ret;
+	struct dt_node_info i2c_info;
+	struct i2c_handle_s *i2c = &i2c_handle;
+	uint32_t i2c_addr = 0U;
+	struct stm32_i2c_init_s i2c_init;
+
+	ret = dt_pmic2_i2c_config(&i2c_info, &i2c_init, &i2c_addr);
+	if (ret < 0) {
+		ERROR("I2C configuration failed %d\n", ret);
+		panic();
+	}
+
+	if (ret != 0) {
+		return false;
+	}
+
+	/* Initialize PMIC I2C */
+	i2c->i2c_base_addr		= i2c_info.base;
+	i2c->dt_status			= i2c_info.status;
+	i2c->clock			= i2c_info.clock;
+	i2c->i2c_state			= I2C_STATE_RESET;
+	i2c_init.own_address1		= i2c_addr;
+	i2c_init.addressing_mode	= I2C_ADDRESSINGMODE_7BIT;
+	i2c_init.dual_address_mode	= I2C_DUALADDRESS_DISABLE;
+	i2c_init.own_address2		= 0;
+	i2c_init.own_address2_masks	= I2C_OAR2_OA2NOMASK;
+	i2c_init.general_call_mode	= I2C_GENERALCALL_DISABLE;
+	i2c_init.no_stretch_mode	= I2C_NOSTRETCH_DISABLE;
+	i2c_init.analog_filter		= 1;
+	i2c_init.digital_filter_coef	= 0;
+
+	ret = stm32_i2c_init(i2c, &i2c_init);
+	if (ret != 0) {
+		ERROR("Cannot initialize I2C %x (%d)\n",
+		      i2c->i2c_base_addr, ret);
+		panic();
+	}
+
+	if (!stm32_i2c_is_device_ready(i2c, i2c_addr, 1,
+				       I2C_TIMEOUT_BUSY_MS)) {
+		ERROR("I2C device not ready\n");
+		panic();
+	}
+
+	pmic2 = &pmic2_handle;
+	pmic2->i2c_handle = &i2c_handle;
+	pmic2->i2c_addr = i2c_addr;
+
+	return true;
+}
+
+static int pmic2_set_state(const struct regul_description *desc, bool enable)
+{
+	struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+
+	VERBOSE("%s: set state to %d\n", desc->node_name, enable);
+
+	return stpmic2_regulator_set_state(pmic2, regul->id, enable);
+}
+
+static int pmic2_get_state(const struct regul_description *desc)
+{
+	struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+	bool enabled;
+
+	VERBOSE("%s: get state\n", desc->node_name);
+
+	if (stpmic2_regulator_get_state(pmic2, regul->id, &enabled) < 0) {
+		panic();
+	}
+
+	return enabled;
+}
+
+static int pmic2_get_voltage(const struct regul_description *desc)
+{
+	struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+	uint16_t mv;
+
+	VERBOSE("%s: get volt\n", desc->node_name);
+
+	if (regul->bypass_mv != 0U) {
+		int ret;
+
+		/* If the regul is in bypass mode, return bypass value */
+		ret = stpmic2_regulator_get_prop(pmic2, regul->id, STPMIC2_BYPASS);
+		if (ret < 0) {
+			return ret;
+		}
+
+		if (ret == 1) {
+			return regul->bypass_mv;
+		}
+	};
+
+	if (stpmic2_regulator_get_voltage(pmic2, regul->id, &mv) < 0) {
+		panic();
+	}
+
+	return mv;
+}
+
+static int pmic2_set_voltage(const struct regul_description *desc, uint16_t mv)
+{
+	struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+
+	VERBOSE("%s: set volt\n", desc->node_name);
+
+	if (regul->bypass_mv != 0U) {
+		int ret;
+
+		/* If the regul is in bypass mode, authorize bypass mV */
+		ret = stpmic2_regulator_get_prop(pmic2, regul->id, STPMIC2_BYPASS);
+		if (ret < 0) {
+			return ret;
+		}
+
+		if ((ret == 1) && (mv != regul->bypass_mv)) {
+			return -EPERM;
+		}
+	};
+
+	return stpmic2_regulator_set_voltage(pmic2, regul->id, mv);
+}
+
+static int pmic2_list_voltages(const struct regul_description *desc,
+			       const uint16_t **levels, size_t *count)
+{
+	struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+
+	VERBOSE("%s: list volt\n", desc->node_name);
+
+	if (regul->bypass_mv != 0U) {
+		int ret;
+
+		ret = stpmic2_regulator_get_prop(pmic2, regul->id, STPMIC2_BYPASS);
+		if (ret < 0) {
+			return ret;
+		}
+
+		/* bypass is enabled, return a list with only bypass mV */
+		if (ret == 1) {
+			if (count != NULL) {
+				*count = 1U;
+			}
+			if (levels != NULL) {
+				*levels = &regul->bypass_mv;
+			}
+			return 0;
+		}
+	};
+
+	return stpmic2_regulator_levels_mv(pmic2, regul->id, levels, count);
+}
+
+static int pmic2_set_flag(const struct regul_description *desc, uint16_t flag)
+{
+	struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+	uint32_t id = regul->id;
+	int ret = -EPERM;
+
+	VERBOSE("%s: set_flag 0x%x\n", desc->node_name, flag);
+
+	switch (flag) {
+	case REGUL_PULL_DOWN:
+		ret = stpmic2_regulator_set_prop(pmic2, id, STPMIC2_PULL_DOWN, 1U);
+		break;
+	case REGUL_OCP:
+		ret = stpmic2_regulator_set_prop(pmic2, id, STPMIC2_OCP, 1U);
+		break;
+	case REGUL_SINK_SOURCE:
+		ret = stpmic2_regulator_set_prop(pmic2, id, STPMIC2_SINK_SOURCE, 1U);
+		break;
+	case REGUL_ENABLE_BYPASS:
+		ret = stpmic2_regulator_set_prop(pmic2, id, STPMIC2_BYPASS, 1U);
+		break;
+	case REGUL_MASK_RESET:
+		ret = stpmic2_regulator_set_prop(pmic2, id, STPMIC2_MASK_RESET, 1U);
+		break;
+	default:
+		ERROR("Invalid flag %u", flag);
+		panic();
+	}
+
+	if (ret != 0) {
+		return -EPERM;
+	}
+
+	return 0;
+}
+
+int stpmic2_set_prop(const struct regul_description *desc, uint16_t prop, uint32_t value)
+{
+	struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+	int ret;
+
+	VERBOSE("%s: set_prop 0x%x val=%u\n", desc->node_name, prop, value);
+
+	ret = stpmic2_regulator_set_prop(pmic2, regul->id, prop, value);
+	if (ret != 0)
+		return -EPERM;
+
+	return 0;
+}
+
+static struct regul_ops pmic2_ops = {
+	.set_state = pmic2_set_state,
+	.get_state = pmic2_get_state,
+	.set_voltage = pmic2_set_voltage,
+	.get_voltage = pmic2_get_voltage,
+	.list_voltages = pmic2_list_voltages,
+	.set_flag = pmic2_set_flag,
+};
+
+#define DEFINE_PMIC_REGUL_HANDLE(rid) \
+[(rid)] = { \
+	.id = (rid), \
+}
+
+static struct regul_handle_s pmic2_regul_handles[STPMIC2_NB_REG] = {
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_BUCK1),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_BUCK2),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_BUCK3),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_BUCK4),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_BUCK5),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_BUCK6),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_BUCK7),
+
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO1),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO2),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO3),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO4),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO5),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO6),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO7),
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_LDO8),
+
+	DEFINE_PMIC_REGUL_HANDLE(STPMIC2_REFDDR),
+};
+
+#define DEFINE_REGUL(rid, name) \
+[rid] = { \
+	.node_name = name, \
+	.ops = &pmic2_ops, \
+	.driver_data = &pmic2_regul_handles[rid], \
+}
+
+static const struct regul_description pmic2_descs[STPMIC2_NB_REG] = {
+	DEFINE_REGUL(STPMIC2_BUCK1, "buck1"),
+	DEFINE_REGUL(STPMIC2_BUCK2, "buck2"),
+	DEFINE_REGUL(STPMIC2_BUCK3, "buck3"),
+	DEFINE_REGUL(STPMIC2_BUCK4, "buck4"),
+	DEFINE_REGUL(STPMIC2_BUCK5, "buck5"),
+	DEFINE_REGUL(STPMIC2_BUCK6, "buck6"),
+	DEFINE_REGUL(STPMIC2_BUCK7, "buck7"),
+
+	DEFINE_REGUL(STPMIC2_LDO1, "ldo1"),
+	DEFINE_REGUL(STPMIC2_LDO2, "ldo2"),
+	DEFINE_REGUL(STPMIC2_LDO3, "ldo3"),
+	DEFINE_REGUL(STPMIC2_LDO4, "ldo4"),
+	DEFINE_REGUL(STPMIC2_LDO5, "ldo5"),
+	DEFINE_REGUL(STPMIC2_LDO6, "ldo6"),
+	DEFINE_REGUL(STPMIC2_LDO7, "ldo7"),
+	DEFINE_REGUL(STPMIC2_LDO8, "ldo8"),
+
+	DEFINE_REGUL(STPMIC2_REFDDR, "refddr"),
+};
+
+static int register_pmic2(void)
+{
+	void *fdt;
+	int pmic_node, regulators_node, subnode;
+
+	VERBOSE("Register pmic2\n");
+
+	if (fdt_get_address(&fdt) == 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	pmic_node = dt_get_pmic_node(fdt);
+	if (pmic_node < 0) {
+		return pmic_node;
+	}
+
+	regulators_node = fdt_subnode_offset(fdt, pmic_node, "regulators");
+	if (regulators_node < 0) {
+		return -ENOENT;
+	}
+
+	fdt_for_each_subnode(subnode, fdt, regulators_node) {
+		const char *reg_name = fdt_get_name(fdt, subnode, NULL);
+		const struct regul_description *desc;
+		unsigned int i;
+		int ret;
+		const fdt32_t *cuint;
+
+		for (i = 0; i < STPMIC2_NB_REG; i++) {
+			desc = &pmic2_descs[i];
+			if (strcmp(desc->node_name, reg_name) == 0) {
+				break;
+			}
+		}
+		assert(i < STPMIC2_NB_REG);
+
+		ret = regulator_register(desc, subnode);
+		if (ret != 0) {
+			WARN("%s:%d failed to register %s\n", __func__,
+			     __LINE__, reg_name);
+			return ret;
+		}
+
+		cuint = fdt_getprop(fdt, subnode, "st,regulator-bypass-microvolt", NULL);
+		if (cuint != NULL) {
+			struct regul_handle_s *regul = (struct regul_handle_s *)desc->driver_data;
+
+			regul->bypass_mv = (uint16_t)(fdt32_to_cpu(*cuint) / 1000U);
+			VERBOSE("%s: bypass voltage=%umV\n", desc->node_name,
+				regul->bypass_mv);
+		}
+
+		if (fdt_getprop(fdt, subnode, "st,mask-reset", NULL)  != NULL) {
+			VERBOSE("%s: set mask-reset\n", desc->node_name);
+			ret = pmic2_set_flag(desc, REGUL_MASK_RESET);
+			if (ret != 0) {
+				ERROR("set mask-reset failed\n");
+				return ret;
+			}
+		}
+
+		if (fdt_getprop(fdt, subnode, "st,regulator-sink-source", NULL) != NULL) {
+			VERBOSE("%s: set regulator-sink-source\n", desc->node_name);
+			ret = pmic2_set_flag(desc, REGUL_SINK_SOURCE);
+			if (ret != 0) {
+				ERROR("set regulator-sink-source failed\n");
+				return ret;
+			}
+		}
+	}
+
+	return 0;
+}
+
+void initialize_pmic(void)
+{
+	int ret;
+	uint8_t val;
+
+	ret = initialize_pmic_i2c();
+	if (!ret) {
+		VERBOSE("No PMIC2\n");
+		return;
+	}
+
+	if (stpmic2_get_version(pmic2, &val) != 0) {
+		ERROR("Failed to access PMIC\n");
+		panic();
+	}
+	INFO("PMIC2 version = 0x%02x\n", val);
+
+	if (stpmic2_get_product_id(pmic2, &val) != 0) {
+		ERROR("Failed to access PMIC\n");
+		panic();
+	}
+	INFO("PMIC2 product ID = 0x%02x\n", val);
+
+	ret = register_pmic2();
+	if (ret < 0) {
+		ERROR("Register pmic2 failed\n");
+		panic();
+	}
+
+#if EVENT_LOG_LEVEL == LOG_LEVEL_VERBOSE
+	stpmic2_dump_regulators(pmic2);
+#endif
+}