text: // SPDX-License-Identifier: GPL-2.0
  //
  // Device driver for regulators in Hisi IC
  //
  // Copyright (c) 2013 Linaro Ltd.
  // Copyright (c) 2011 HiSilicon Ltd.
  // Copyright (c) 2020-2021 Huawei Technologies Co., Ltd
  //
  // Guodong Xu <guodong.xu@linaro.org>
  
  #include <linux/delay.h>
  #include <linux/mfd/hi6421-spmi-pmic.h>
  #include <linux/module.h>
  #include <linux/platform_device.h>
  #include <linux/regmap.h>
  #include <linux/regulator/driver.h>
  #include <linux/spmi.h>
  
  struct hi6421_spmi_reg_info {
  	struct regulator_desc	desc;
  	struct hi6421_spmi_pmic *pmic;
  	u8			eco_mode_mask;
  	u32			eco_uA;
  
  	/* Serialize regulator enable logic */
  	struct mutex enable_mutex;
  };
  
  static const unsigned int ldo3_voltages[] = {
  	1500000, 1550000, 1600000, 1650000,
  	1700000, 1725000, 1750000, 1775000,
  	1800000, 1825000, 1850000, 1875000,
  	1900000, 1925000, 1950000, 2000000
  };
  
  static const unsigned int ldo4_voltages[] = {
  	1725000, 1750000, 1775000, 1800000,
  	1825000, 1850000, 1875000, 1900000
  };
  
  static const unsigned int ldo9_voltages[] = {
  	1750000, 1800000, 1825000, 2800000,
  	2850000, 2950000, 3000000, 3300000
  };
  
  static const unsigned int ldo15_voltages[] = {
  	1800000, 1850000, 2400000, 2600000,
  	2700000, 2850000, 2950000, 3000000
  };
  
  static const unsigned int ldo17_voltages[] = {
  	2500000, 2600000, 2700000, 2800000,
  	3000000, 3100000, 3200000, 3300000
  };
  
  static const unsigned int ldo34_voltages[] = {
  	2600000, 2700000, 2800000, 2900000,
  	3000000, 3100000, 3200000, 3300000
  };
  
  /**
   * HI6421V600_LDO() - specify a LDO power line
   * @_id: LDO id name string
   * @vtable: voltage table
   * @ereg: enable register
   * @emask: enable mask
   * @vreg: voltage select register
   * @odelay: off/on delay time in uS
   * @etime: enable time in uS
   * @ecomask: eco mode mask
   * @ecoamp: eco mode load uppler limit in uA
   */
  #define HI6421V600_LDO(_id, vtable, ereg, emask, vreg,			       \
  		       odelay, etime, ecomask, ecoamp)			       \
  	[HI6421V600_##_id] = {						       \
  		.desc = {						       \
  			.name		= #_id,				       \
  			.of_match        = of_match_ptr(#_id),		       \
  			.regulators_node = of_match_ptr("regulators"),	       \
  			.ops		= &hi6421_spmi_ldo_rops,	       \
  			.type		= REGULATOR_VOLTAGE,		       \
  			.id		= HI6421V600_##_id,		       \
  			.owner		= THIS_MODULE,			       \
  			.volt_table	= vtable,			       \
  			.n_voltages	= ARRAY_SIZE(vtable),		       \
  			.vsel_mask	= ARRAY_SIZE(vtable) - 1,	       \
  			.vsel_reg	= vreg,				       \
  			.enable_reg	= ereg,				       \
  			.enable_mask	= emask,			       \
  			.enable_time	= etime,			       \
  			.ramp_delay	= etime,			       \
  			.off_on_delay	= odelay,			       \
  		},							       \
  		.eco_mode_mask		= ecomask,			       \
  		.eco_uA			= ecoamp,			       \
  	}
  
  static int hi6421_spmi_regulator_enable(struct regulator_dev *rdev)
  {
  	struct hi6421_spmi_reg_info *sreg = rdev_get_drvdata(rdev);
  	struct hi6421_spmi_pmic *pmic = sreg->pmic;
  	int ret;
  
  	/* cannot enable more than one regulator at one time */
  	mutex_lock(&sreg->enable_mutex);
  
  	ret = regmap_update_bits(pmic->regmap, rdev->desc->enable_reg,
  				 rdev->desc->enable_mask,
  				 rdev->desc->enable_mask);
  
  	/* Avoid powering up multiple devices at the same time */
  	usleep_range(rdev->desc->off_on_delay, rdev->desc->off_on_delay + 60);
  
  	mutex_unlock(&sreg->enable_mutex);
  
  	return ret;
  }
  
  static int hi6421_spmi_regulator_disable(struct regulator_dev *rdev)
  {
  	struct hi6421_spmi_reg_info *sreg = rdev_get_drvdata(rdev);
  	struct hi6421_spmi_pmic *pmic = sreg->pmic;
  
  	return regmap_update_bits(pmic->regmap, rdev->desc->enable_reg,
  				  rdev->desc->enable_mask, 0);
  }
  
  static unsigned int hi6421_spmi_regulator_get_mode(struct regulator_dev *rdev)
  {
  	struct hi6421_spmi_reg_info *sreg = rdev_get_drvdata(rdev);
  	struct hi6421_spmi_pmic *pmic = sreg->pmic;
  	unsigned int reg_val;
  
  	regmap_read(pmic->regmap, rdev->desc->enable_reg, &reg_val);
  
  	if (reg_val & sreg->eco_mode_mask)
  		return REGULATOR_MODE_IDLE;
  
  	return REGULATOR_MODE_NORMAL;
  }
  
  static int hi6421_spmi_regulator_set_mode(struct regulator_dev *rdev,
  					  unsigned int mode)
  {
  	struct hi6421_spmi_reg_info *sreg = rdev_get_drvdata(rdev);
  	struct hi6421_spmi_pmic *pmic = sreg->pmic;
  	unsigned int val;
  
  	switch (mode) {
  	case REGULATOR_MODE_NORMAL:
  		val = 0;
  		break;
  	case REGULATOR_MODE_IDLE:
  		if (!sreg->eco_mode_mask)
  			return -EINVAL;
  
  		val = sreg->eco_mode_mask;
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	return regmap_update_bits(pmic->regmap, rdev->desc->enable_reg,
  				  sreg->eco_mode_mask, val);
  }
  
  static unsigned int
  hi6421_spmi_regulator_get_optimum_mode(struct regulator_dev *rdev,
  				       int input_uV, int output_uV,
  				       int load_uA)
  {
  	struct hi6421_spmi_reg_info *sreg = rdev_get_drvdata(rdev);
  
  	if (!sreg->eco_uA || ((unsigned int)load_uA > sreg->eco_uA))
  		return REGULATOR_MODE_NORMAL;
  
  	return REGULATOR_MODE_IDLE;
  }
  
  static const struct regulator_ops hi6421_spmi_ldo_rops = {
  	.is_enabled = regulator_is_enabled_regmap,
  	.enable = hi6421_spmi_regulator_enable,
  	.disable = hi6421_spmi_regulator_disable,
  	.list_voltage = regulator_list_voltage_table,
  	.map_voltage = regulator_map_voltage_iterate,
  	.get_voltage_sel = regulator_get_voltage_sel_regmap,
  	.set_voltage_sel = regulator_set_voltage_sel_regmap,
  	.get_mode = hi6421_spmi_regulator_get_mode,
  	.set_mode = hi6421_spmi_regulator_set_mode,
  	.get_optimum_mode = hi6421_spmi_regulator_get_optimum_mode,
  };
  
  /* HI6421v600 regulators with known registers */
  enum hi6421_spmi_regulator_id {
  	HI6421V600_LDO3,
  	HI6421V600_LDO4,
  	HI6421V600_LDO9,
  	HI6421V600_LDO15,
  	HI6421V600_LDO16,
  	HI6421V600_LDO17,
  	HI6421V600_LDO33,
  	HI6421V600_LDO34,
  };
  
  static struct hi6421_spmi_reg_info regulator_info[] = {
  	HI6421V600_LDO(LDO3, ldo3_voltages,
  		       0x16, 0x01, 0x51,
  		       20000, 120,
  		       0, 0),
  	HI6421V600_LDO(LDO4, ldo4_voltages,
  		       0x17, 0x01, 0x52,
  		       20000, 120,
  		       0x10, 10000),
  	HI6421V600_LDO(LDO9, ldo9_voltages,
  		       0x1c, 0x01, 0x57,
  		       20000, 360,
  		       0x10, 10000),
  	HI6421V600_LDO(LDO15, ldo15_voltages,
  		       0x21, 0x01, 0x5c,
  		       20000, 360,
  		       0x10, 10000),
  	HI6421V600_LDO(LDO16, ldo15_voltages,
  		       0x22, 0x01, 0x5d,
  		       20000, 360,
  		       0x10, 10000),
  	HI6421V600_LDO(LDO17, ldo17_voltages,
  		       0x23, 0x01, 0x5e,
  		       20000, 120,
  		       0x10, 10000),
  	HI6421V600_LDO(LDO33, ldo17_voltages,
  		       0x32, 0x01, 0x6d,
  		       20000, 120,
  		       0, 0),
  	HI6421V600_LDO(LDO34, ldo34_voltages,
  		       0x33, 0x01, 0x6e,
  		       20000, 120,
  		       0, 0),
  };
  
  static int hi6421_spmi_regulator_probe(struct platform_device *pdev)
  {
  	struct device *pmic_dev = pdev->dev.parent;
  	struct regulator_config config = { };
  	struct hi6421_spmi_reg_info *sreg;
  	struct hi6421_spmi_reg_info *info;
  	struct device *dev = &pdev->dev;
  	struct hi6421_spmi_pmic *pmic;
  	struct regulator_dev *rdev;
  	int i;
  
  	/*
  	 * This driver is meant to be called by hi6421-spmi-core,
  	 * which should first set drvdata. If this doesn't happen, hit
  	 * a warn on and return.
  	 */
  	pmic = dev_get_drvdata(pmic_dev);
  	if (WARN_ON(!pmic))
  		return -ENODEV;
  
  	sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
  	if (!sreg)
  		return -ENOMEM;
  
  	sreg->pmic = pmic;
  	mutex_init(&sreg->enable_mutex);
  
  	for (i = 0; i < ARRAY_SIZE(regulator_info); i++) {
  		info = &regulator_info[i];
  
  		config.dev = pdev->dev.parent;
  		config.driver_data = sreg;
  		config.regmap = pmic->regmap;
  
  		rdev = devm_regulator_register(dev, &info->desc, &config);
  		if (IS_ERR(rdev)) {
  			dev_err(dev, "failed to register %s\n",
  				info->desc.name);
  			return PTR_ERR(rdev);
  		}
  	}
  
  	return 0;
  }
  
  static const struct platform_device_id hi6421_spmi_regulator_table[] = {
  	{ .name = "hi6421v600-regulator" },
  	{},
  };
  MODULE_DEVICE_TABLE(platform, hi6421_spmi_regulator_table);
  
  static struct platform_driver hi6421_spmi_regulator_driver = {
  	.id_table = hi6421_spmi_regulator_table,
  	.driver = {
  		.name = "hi6421v600-regulator",
  	},
  	.probe	= hi6421_spmi_regulator_probe,
  };
  module_platform_driver(hi6421_spmi_regulator_driver);
  
  MODULE_DESCRIPTION("Hi6421v600 SPMI regulator driver");
  MODULE_LICENSE("GPL v2");
  
  