[PATCH V2 3/4] regulator: Add a regulator driver for the PM8008 PMIC

From: Satya Priya
Date: Fri Oct 01 2021 - 00:01:48 EST

From: satya priya <skakit@xxxxxxxxxxxxxx>

Qualcomm Technologies, Inc. PM8008 is an I2C controlled PMIC
containing 7 LDO regulators. Add a PM8008 regulator driver to
support PMIC regulator management via the regulator framework.

Signed-off-by: satya priya <skakit@xxxxxxxxxxxxxx>
---
Changes in V2:
- As per Mark's comments
- Using regmap helpers for regulator enable/disable and is_enabled APIs
- Changed pr_err to dev_err wherever possible.
- Removed init_voltage property as it is not used.
- Removed if check for registering LDOs
- Other minor changes.

drivers/regulator/Kconfig | 9 +
drivers/regulator/Makefile | 1 +
drivers/regulator/qcom-pm8008-regulator.c | 320 ++++++++++++++++++++++++++++++
3 files changed, 330 insertions(+)
create mode 100644 drivers/regulator/qcom-pm8008-regulator.c

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 27578e9..95d234f 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -916,6 +916,15 @@ config REGULATOR_PWM
This driver supports PWM controlled voltage regulators. PWM
duty cycle can increase or decrease the voltage.

+config REGULATOR_QCOM_PM8008
+ tristate "Qualcomm Technologies, Inc. PM8008 PMIC regulators"
+ depends on MFD_QCOM_PM8008
+ help
+ Select this option to get support for the voltage regulators
+ of Qualcomm Technologies, Inc. PM8008 PMIC chip. PM8008 has 7 LDO
+ regulators. This driver provides support for basic operations like
+ set/get voltage and enable/disable.
+
config REGULATOR_QCOM_RPM
tristate "Qualcomm RPM regulator driver"
depends on MFD_QCOM_RPM
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 9e382b5..5e935ff 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -100,6 +100,7 @@ obj-$(CONFIG_REGULATOR_MT6380) += mt6380-regulator.o
obj-$(CONFIG_REGULATOR_MT6397) += mt6397-regulator.o
obj-$(CONFIG_REGULATOR_MTK_DVFSRC) += mtk-dvfsrc-regulator.o
obj-$(CONFIG_REGULATOR_QCOM_LABIBB) += qcom-labibb-regulator.o
+obj-$(CONFIG_REGULATOR_QCOM_PM8008) += qcom-pm8008-regulator.o
obj-$(CONFIG_REGULATOR_QCOM_RPM) += qcom_rpm-regulator.o
obj-$(CONFIG_REGULATOR_QCOM_RPMH) += qcom-rpmh-regulator.o
obj-$(CONFIG_REGULATOR_QCOM_SMD_RPM) += qcom_smd-regulator.o
diff --git a/drivers/regulator/qcom-pm8008-regulator.c b/drivers/regulator/qcom-pm8008-regulator.c
new file mode 100644
index 0000000..5dacaa4
--- /dev/null
+++ b/drivers/regulator/qcom-pm8008-regulator.c
@@ -0,0 +1,320 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2021, The Linux Foundation. All rights reserved. */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/string.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+
+#define STARTUP_DELAY_USEC 20
+#define VSET_STEP_MV 8
+#define VSET_STEP_UV (VSET_STEP_MV * 1000)
+
+#define LDO_ENABLE_REG(base) (base + 0x46)
+#define ENABLE_BIT BIT(7)
+
+#define LDO_STATUS1_REG(base) (base + 0x08)
+#define VREG_READY_BIT BIT(7)
+
+#define LDO_VSET_LB_REG(base) (base + 0x40)
+
+#define LDO_STEPPER_CTL_REG(base) (base + 0x3b)
+#define STEP_RATE_MASK GENMASK(1, 0)
+
+#define PM8008_MAX_LDO 7
+
+struct regulator_data {
+ char *name;
+ char *supply_name;
+ int min_uv;
+ int max_uv;
+ int min_dropout_uv;
+};
+
+struct pm8008_regulator {
+ struct device *dev;
+ struct regmap *regmap;
+ struct regulator_desc rdesc;
+ struct regulator_dev *rdev;
+ struct device_node *of_node;
+ u16 base;
+ int step_rate;
+};
+
+static const struct regulator_data reg_data[PM8008_MAX_LDO] = {
+ /* name parent min_uv max_uv headroom_uv */
+ {"l1", "vdd_l1_l2", 528000, 1504000, 225000},
+ {"l2", "vdd_l1_l2", 528000, 1504000, 225000},
+ {"l3", "vdd_l3_l4", 1504000, 3400000, 200000},
+ {"l4", "vdd_l3_l4", 1504000, 3400000, 200000},
+ {"l5", "vdd_l5", 1504000, 3400000, 300000},
+ {"l6", "vdd_l6", 1504000, 3400000, 300000},
+ {"l7", "vdd_l7", 1504000, 3400000, 300000},
+};
+
+static int pm8008_read(struct regmap *regmap, u16 reg, u8 *val, int count)
+{
+ int rc;
+
+ rc = regmap_bulk_read(regmap, reg, val, count);
+ if (rc < 0)
+ pr_err("failed to read %#x, rc=%d\n", reg, rc);
+
+ return rc;
+}
+
+static int pm8008_write(struct regmap *regmap, u16 reg, u8 *val, int count)
+{
+ int rc;
+
+ pr_debug("Writing [%*ph] from address %#x\n", count, val, reg);
+ rc = regmap_bulk_write(regmap, reg, val, count);
+ if (rc < 0)
+ pr_err("failed to write %#x rc=%d\n", reg, rc);
+
+ return rc;
+}
+
+static int pm8008_regulator_get_voltage(struct regulator_dev *rdev)
+{
+ struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
+ u8 vset_raw[2];
+ int rc;
+
+ rc = pm8008_read(pm8008_reg->regmap,
+ LDO_VSET_LB_REG(pm8008_reg->base),
+ vset_raw, 2);
+ if (rc < 0) {
+ dev_err(pm8008_reg->dev, "failed to read regulator voltage rc=%d\n", rc);
+ return rc;
+ }
+
+ return (vset_raw[1] << 8 | vset_raw[0]) * 1000;
+}
+
+static inline int pm8008_write_voltage(struct pm8008_regulator *pm8008_reg, int min_uv,
+ int max_uv)
+{
+ int rc = 0, mv;
+ u8 vset_raw[2];
+
+ mv = DIV_ROUND_UP(min_uv, 1000);
+
+ /*
+ * Each LSB of regulator is 1mV and the voltage setpoint
+ * should be multiple of 8mV(step).
+ */
+ mv = DIV_ROUND_UP(mv, VSET_STEP_MV) * VSET_STEP_MV;
+ if (mv * 1000 > max_uv) {
+ dev_err(pm8008_reg->dev,
+ "requested voltage (%d uV) above maximum limit (%d uV)\n",
+ mv*1000, max_uv);
+ return -EINVAL;
+ }
+
+ vset_raw[0] = mv & 0xff;
+ vset_raw[1] = (mv & 0xff00) >> 8;
+ rc = pm8008_write(pm8008_reg->regmap, LDO_VSET_LB_REG(pm8008_reg->base),
+ vset_raw, 2);
+ if (rc < 0) {
+ dev_err(pm8008_reg->dev, "failed to write voltage rc=%d\n", rc);
+ return rc;
+ }
+
+ return 0;
+}
+
+static int pm8008_regulator_set_voltage_time(struct regulator_dev *rdev,
+ int old_uV, int new_uv)
+{
+ struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
+
+ return DIV_ROUND_UP(abs(new_uv - old_uV), pm8008_reg->step_rate);
+}
+
+static int pm8008_regulator_set_voltage(struct regulator_dev *rdev,
+ int min_uv, int max_uv, unsigned int *selector)
+{
+ struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
+ int rc;
+
+ rc = pm8008_write_voltage(pm8008_reg, min_uv, max_uv);
+ if (rc < 0)
+ return rc;
+
+ *selector = DIV_ROUND_UP(min_uv - pm8008_reg->rdesc.min_uV,
+ VSET_STEP_UV);
+
+ dev_dbg(pm8008_reg->dev, "voltage set to %d\n", min_uv);
+ return 0;
+}
+
+static const struct regulator_ops pm8008_regulator_ops = {
+ .enable = regulator_enable_regmap,
+ .disable = regulator_disable_regmap,
+ .is_enabled = regulator_is_enabled_regmap,
+ .set_voltage = pm8008_regulator_set_voltage,
+ .get_voltage = pm8008_regulator_get_voltage,
+ .list_voltage = regulator_list_voltage_linear,
+ .set_voltage_time = pm8008_regulator_set_voltage_time,
+};
+
+static int pm8008_register_ldo(struct pm8008_regulator *pm8008_reg,
+ const char *name)
+{
+ struct regulator_config reg_config = {};
+ struct regulator_init_data *init_data;
+ struct device *dev = pm8008_reg->dev;
+ struct device_node *reg_node = pm8008_reg->of_node;
+ int rc, i;
+ u32 base = 0;
+ u8 reg;
+
+ /* get regulator data */
+ for (i = 0; i < PM8008_MAX_LDO; i++)
+ if (strstr(name, reg_data[i].name))
+ break;
+
+ if (i == PM8008_MAX_LDO) {
+ dev_err(dev, "Invalid regulator name %s\n", name);
+ return -EINVAL;
+ }
+
+ rc = of_property_read_u32(reg_node, "reg", &base);
+ if (rc < 0) {
+ dev_err(dev, "%s: failed to get regulator base rc=%d\n", name, rc);
+ return rc;
+ }
+ pm8008_reg->base = base;
+
+ /* get slew rate */
+ rc = pm8008_read(pm8008_reg->regmap,
+ LDO_STEPPER_CTL_REG(pm8008_reg->base), &reg, 1);
+ if (rc < 0) {
+ dev_err(dev, "%s: failed to read step rate configuration rc=%d\n",
+ name, rc);
+ return rc;
+ }
+ pm8008_reg->step_rate = 38400 >> (reg & STEP_RATE_MASK);
+
+ init_data = of_get_regulator_init_data(dev, reg_node,
+ &pm8008_reg->rdesc);
+ if (init_data == NULL) {
+ dev_err(dev, "%s: failed to get regulator data\n", name);
+ return -ENODATA;
+ }
+
+ init_data->constraints.input_uV = init_data->constraints.max_uV;
+ reg_config.dev = dev;
+ reg_config.init_data = init_data;
+ reg_config.driver_data = pm8008_reg;
+ reg_config.of_node = reg_node;
+
+ pm8008_reg->rdesc.type = REGULATOR_VOLTAGE;
+ pm8008_reg->rdesc.ops = &pm8008_regulator_ops;
+ pm8008_reg->rdesc.name = init_data->constraints.name;
+ pm8008_reg->rdesc.supply_name = reg_data[i].supply_name;
+ pm8008_reg->rdesc.uV_step = VSET_STEP_UV;
+ pm8008_reg->rdesc.min_uV = reg_data[i].min_uv;
+ pm8008_reg->rdesc.n_voltages
+ = ((reg_data[i].max_uv - reg_data[i].min_uv)
+ / pm8008_reg->rdesc.uV_step) + 1;
+
+ pm8008_reg->rdesc.enable_reg = LDO_ENABLE_REG(base);
+ pm8008_reg->rdesc.enable_mask = ENABLE_BIT;
+ pm8008_reg->rdesc.min_dropout_uV = reg_data[i].min_dropout_uv;
+ of_property_read_u32(reg_node, "qcom,min-dropout-voltage",
+ &pm8008_reg->rdesc.min_dropout_uV);
+
+ pm8008_reg->rdev = devm_regulator_register(dev, &pm8008_reg->rdesc,
+ &reg_config);
+ if (IS_ERR(pm8008_reg->rdev)) {
+ rc = PTR_ERR(pm8008_reg->rdev);
+ dev_err(dev, "%s: failed to register regulator rc=%d\n",
+ pm8008_reg->rdesc.name, rc);
+ return rc;
+ }
+
+ dev_dbg(dev, "%s regulator registered\n", name);
+
+ return 0;
+}
+
+static int pm8008_parse_regulator(struct regmap *regmap, struct device *dev)
+{
+ int rc = 0;
+ const char *name;
+ struct device_node *child;
+ struct pm8008_regulator *pm8008_reg;
+
+ /* parse each subnode and register regulator for regulator child */
+ for_each_available_child_of_node(dev->of_node, child) {
+ pm8008_reg = devm_kzalloc(dev, sizeof(*pm8008_reg), GFP_KERNEL);
+
+ pm8008_reg->regmap = regmap;
+ pm8008_reg->of_node = child;
+ pm8008_reg->dev = dev;
+
+ rc = of_property_read_string(child, "regulator-name", &name);
+ if (rc)
+ continue;
+
+ rc = pm8008_register_ldo(pm8008_reg, name);
+ if (rc < 0) {
+ dev_err(dev, "failed to register regulator %s rc=%d\n",
+ name, rc);
+ return rc;
+ }
+ }
+
+ return 0;
+}
+
+static int pm8008_regulator_probe(struct platform_device *pdev)
+{
+ int rc = 0;
+ struct regmap *regmap;
+
+ regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!regmap) {
+ dev_err(&pdev->dev, "parent regmap is missing\n");
+ return -EINVAL;
+ }
+
+ rc = pm8008_parse_regulator(regmap, &pdev->dev);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "failed to parse device tree rc=%d\n", rc);
+ return rc;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id pm8008_regulator_match_table[] = {
+ { .compatible = "qcom,pm8008-regulator", },
+ { },
+};
+
+static struct platform_driver pm8008_regulator_driver = {
+ .driver = {
+ .name = "qcom,pm8008-regulator",
+ .of_match_table = pm8008_regulator_match_table,
+ },
+ .probe = pm8008_regulator_probe,
+};
+
+module_platform_driver(pm8008_regulator_driver);
+
+MODULE_DESCRIPTION("Qualcomm PM8008 PMIC Regulator Driver");
+MODULE_LICENSE("GPL v2");
--
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