regulator: add a regulator driver for the AS3711 PMIC

This driver supports the 4 DCDC and 8 LDO regulators on the AS3711 PMIC.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 379 insertions, 0 deletions

diff --git a/drivers/regulator/as3711-regulator.c b/drivers/regulator/as3711-regulator.c
new file mode 100644
index 000000000000..81578bf7e352
--- /dev/null
+++ b/drivers/regulator/as3711-regulator.c
@@ -0,0 +1,379 @@
+/*
+ * AS3711 PMIC regulator driver, using DCDC Step Down and LDO supplies
+ *
+ * Copyright (C) 2012 Renesas Electronics Corporation
+ * Author: Guennadi Liakhovetski, <g.liakhovetski@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the version 2 of the GNU General Public License as
+ * published by the Free Software Foundation
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/mfd/as3711.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/slab.h>
+
+struct as3711_regulator_info {
+        struct regulator_desc   desc;
+        unsigned int            max_uV;
+};
+
+struct as3711_regulator {
+        struct as3711_regulator_info *reg_info;
+        struct regulator_dev *rdev;
+};
+
+static int as3711_list_voltage_sd(struct regulator_dev *rdev,
+                                  unsigned int selector)
+{
+        if (selector >= rdev->desc->n_voltages)
+                return -EINVAL;
+
+        if (!selector)
+                return 0;
+        if (selector < 0x41)
+                return 600000 + selector * 12500;
+        if (selector < 0x71)
+                return 1400000 + (selector - 0x40) * 25000;
+        return 2600000 + (selector - 0x70) * 50000;
+}
+
+static int as3711_list_voltage_aldo(struct regulator_dev *rdev,
+                                    unsigned int selector)
+{
+        if (selector >= rdev->desc->n_voltages)
+                return -EINVAL;
+
+        if (selector < 0x10)
+                return 1200000 + selector * 50000;
+        return 1800000 + (selector - 0x10) * 100000;
+}
+
+static int as3711_list_voltage_dldo(struct regulator_dev *rdev,
+                                    unsigned int selector)
+{
+        if (selector >= rdev->desc->n_voltages ||
+            (selector > 0x10 && selector < 0x20))
+                return -EINVAL;
+
+        if (selector < 0x11)
+                return 900000 + selector * 50000;
+        return 1750000 + (selector - 0x20) * 50000;
+}
+
+static int as3711_bound_check(struct regulator_dev *rdev,
+                              int *min_uV, int *max_uV)
+{
+        struct as3711_regulator_info *info = container_of(rdev->desc,
+                                        struct as3711_regulator_info, desc);
+        struct as3711_regulator *reg = rdev->reg_data;
+
+        WARN_ON(reg->reg_info != info);
+
+        dev_dbg(&rdev->dev, "%s(), %d, %d, %d\n", __func__,
+                *min_uV, rdev->desc->min_uV, info->max_uV);
+
+        if (*max_uV < *min_uV ||
+            *min_uV >= info->max_uV || rdev->desc->min_uV >= *max_uV)
+                return -EINVAL;
+
+        if (rdev->desc->n_voltages == 1)
+                return 0;
+
+        if (*max_uV > info->max_uV)
+                *max_uV = info->max_uV;
+
+        if (*min_uV < rdev->desc->min_uV)
+                *min_uV = rdev->desc->min_uV;
+
+        return *min_uV;
+}
+
+static int as3711_sel_check(int min, int max, int bottom, int step)
+{
+        int ret, voltage;
+
+        /* Round up min, when dividing: keeps us within the range */
+        ret = (min - bottom + step - 1) / step;
+        voltage = ret * step + bottom;
+        pr_debug("%s(): select %d..%d in %d+N*%d: %d\n", __func__,
+               min, max, bottom, step, ret);
+        if (voltage > max) {
+                /*
+                 * Try 1 down. It will take us below min, but as long we stay
+                 * above bottom, we're fine.
+                 */
+                ret--;
+                voltage = ret * step + bottom;
+                if (voltage < bottom)
+                        return -EINVAL;
+        }
+        return ret;
+}
+
+static int as3711_map_voltage_sd(struct regulator_dev *rdev,
+                                 int min_uV, int max_uV)
+{
+        int ret;
+
+        ret = as3711_bound_check(rdev, &min_uV, &max_uV);
+        if (ret <= 0)
+                return ret;
+
+        if (min_uV <= 1400000)
+                return as3711_sel_check(min_uV, max_uV, 600000, 12500);
+
+        if (min_uV <= 2600000)
+                return as3711_sel_check(min_uV, max_uV, 1400000, 25000) + 0x40;
+
+        return as3711_sel_check(min_uV, max_uV, 2600000, 50000) + 0x70;
+}
+
+/*
+ * The regulator API supports 4 modes of operataion: FAST, NORMAL, IDLE and
+ * STANDBY. We map them in the following way to AS3711 SD1-4 DCDC modes:
+ * FAST:        sdX_fast=1
+ * NORMAL:      low_noise=1
+ * IDLE:        low_noise=0
+ */
+
+static int as3711_set_mode_sd(struct regulator_dev *rdev, unsigned int mode)
+{
+        unsigned int fast_bit = rdev->desc->enable_mask,
+                low_noise_bit = fast_bit << 4;
+        u8 val;
+
+        switch (mode) {
+        case REGULATOR_MODE_FAST:
+                val = fast_bit | low_noise_bit;
+                break;
+        case REGULATOR_MODE_NORMAL:
+                val = low_noise_bit;
+                break;
+        case REGULATOR_MODE_IDLE:
+                val = 0;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        return regmap_update_bits(rdev->regmap, AS3711_SD_CONTROL_1,
+                                  low_noise_bit | fast_bit, val);
+}
+
+static unsigned int as3711_get_mode_sd(struct regulator_dev *rdev)
+{
+        unsigned int fast_bit = rdev->desc->enable_mask,
+                low_noise_bit = fast_bit << 4, mask = fast_bit | low_noise_bit;
+        unsigned int val;
+        int ret = regmap_read(rdev->regmap, AS3711_SD_CONTROL_1, &val);
+
+        if (ret < 0)
+                return ret;
+
+        if ((val & mask) == mask)
+                return REGULATOR_MODE_FAST;
+
+        if ((val & mask) == low_noise_bit)
+                return REGULATOR_MODE_NORMAL;
+
+        if (!(val & mask))
+                return REGULATOR_MODE_IDLE;
+
+        return -EINVAL;
+}
+
+static int as3711_map_voltage_aldo(struct regulator_dev *rdev,
+                                  int min_uV, int max_uV)
+{
+        int ret;
+
+        ret = as3711_bound_check(rdev, &min_uV, &max_uV);
+        if (ret <= 0)
+                return ret;
+
+        if (min_uV <= 1800000)
+                return as3711_sel_check(min_uV, max_uV, 1200000, 50000);
+
+        return as3711_sel_check(min_uV, max_uV, 1800000, 100000) + 0x10;
+}
+
+static int as3711_map_voltage_dldo(struct regulator_dev *rdev,
+                                  int min_uV, int max_uV)
+{
+        int ret;
+
+        ret = as3711_bound_check(rdev, &min_uV, &max_uV);
+        if (ret <= 0)
+                return ret;
+
+        if (min_uV <= 1700000)
+                return as3711_sel_check(min_uV, max_uV, 900000, 50000);
+
+        return as3711_sel_check(min_uV, max_uV, 1750000, 50000) + 0x20;
+}
+
+static struct regulator_ops as3711_sd_ops = {
+        .is_enabled             = regulator_is_enabled_regmap,
+        .enable                 = regulator_enable_regmap,
+        .disable                = regulator_disable_regmap,
+        .get_voltage_sel        = regulator_get_voltage_sel_regmap,
+        .set_voltage_sel        = regulator_set_voltage_sel_regmap,
+        .list_voltage           = as3711_list_voltage_sd,
+        .map_voltage            = as3711_map_voltage_sd,
+        .get_mode               = as3711_get_mode_sd,
+        .set_mode               = as3711_set_mode_sd,
+};
+
+static struct regulator_ops as3711_aldo_ops = {
+        .is_enabled             = regulator_is_enabled_regmap,
+        .enable                 = regulator_enable_regmap,
+        .disable                = regulator_disable_regmap,
+        .get_voltage_sel        = regulator_get_voltage_sel_regmap,
+        .set_voltage_sel        = regulator_set_voltage_sel_regmap,
+        .list_voltage           = as3711_list_voltage_aldo,
+        .map_voltage            = as3711_map_voltage_aldo,
+};
+
+static struct regulator_ops as3711_dldo_ops = {
+        .is_enabled             = regulator_is_enabled_regmap,
+        .enable                 = regulator_enable_regmap,
+        .disable                = regulator_disable_regmap,
+        .get_voltage_sel        = regulator_get_voltage_sel_regmap,
+        .set_voltage_sel        = regulator_set_voltage_sel_regmap,
+        .list_voltage           = as3711_list_voltage_dldo,
+        .map_voltage            = as3711_map_voltage_dldo,
+};
+
+#define AS3711_REG(_id, _en_reg, _en_bit, _vmask, _vshift, _min_uV, _max_uV, _sfx)      \
+        [AS3711_REGULATOR_ ## _id] = {                                                  \
+        .desc = {                                                                       \
+                .name = "as3711-regulator-" # _id,                                      \
+                .id = AS3711_REGULATOR_ ## _id,                                         \
+                .n_voltages = (_vmask + 1),                                             \
+                .ops = &as3711_ ## _sfx ## _ops,                                        \
+                .type = REGULATOR_VOLTAGE,                                              \
+                .owner = THIS_MODULE,                                                   \
+                .vsel_reg = AS3711_ ## _id ## _VOLTAGE,                                 \
+                .vsel_mask = _vmask << _vshift,                                         \
+                .enable_reg = AS3711_ ## _en_reg,                                       \
+                .enable_mask = BIT(_en_bit),                                            \
+                .min_uV = _min_uV,                                                      \
+        },                                                                              \
+        .max_uV = _max_uV,                                                              \
+}
+
+static struct as3711_regulator_info as3711_reg_info[] = {
+        AS3711_REG(SD_1, SD_CONTROL, 0, 0x7f, 0, 612500, 3350000, sd),
+        AS3711_REG(SD_2, SD_CONTROL, 1, 0x7f, 0, 612500, 3350000, sd),
+        AS3711_REG(SD_3, SD_CONTROL, 2, 0x7f, 0, 612500, 3350000, sd),
+        AS3711_REG(SD_4, SD_CONTROL, 3, 0x7f, 0, 612500, 3350000, sd),
+        AS3711_REG(LDO_1, LDO_1_VOLTAGE, 7, 0x1f, 0, 1200000, 3300000, aldo),
+        AS3711_REG(LDO_2, LDO_2_VOLTAGE, 7, 0x1f, 0, 1200000, 3300000, aldo),
+        AS3711_REG(LDO_3, LDO_3_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+        AS3711_REG(LDO_4, LDO_4_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+        AS3711_REG(LDO_5, LDO_5_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+        AS3711_REG(LDO_6, LDO_6_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+        AS3711_REG(LDO_7, LDO_7_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+        AS3711_REG(LDO_8, LDO_8_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+        /* StepUp output voltage depends on supplying regulator */
+};
+
+#define AS3711_REGULATOR_NUM ARRAY_SIZE(as3711_reg_info)
+
+static int as3711_regulator_probe(struct platform_device *pdev)
+{
+        struct as3711_regulator_pdata *pdata = dev_get_platdata(&pdev->dev);
+        struct as3711 *as3711 = dev_get_drvdata(pdev->dev.parent);
+        struct regulator_init_data *reg_data;
+        struct regulator_config config = {.dev = &pdev->dev,};
+        struct as3711_regulator *reg = NULL;
+        struct as3711_regulator *regs;
+        struct regulator_dev *rdev;
+        struct as3711_regulator_info *ri;
+        int ret;
+        int id;
+
+        if (!pdata)
+                dev_dbg(&pdev->dev, "No platform data...\n");
+
+        regs = devm_kzalloc(&pdev->dev, AS3711_REGULATOR_NUM *
+                        sizeof(struct as3711_regulator), GFP_KERNEL);
+        if (!regs) {
+                dev_err(&pdev->dev, "Memory allocation failed exiting..\n");
+                return -ENOMEM;
+        }
+
+        for (id = 0, ri = as3711_reg_info; id < AS3711_REGULATOR_NUM; ++id, ri++) {
+                reg_data = pdata ? pdata->init_data[id] : NULL;
+
+                /* No need to register if there is no regulator data */
+                if (!ri->desc.name)
+                        continue;
+
+                reg = &regs[id];
+                reg->reg_info = ri;
+
+                config.init_data = reg_data;
+                config.driver_data = reg;
+                config.regmap = as3711->regmap;
+
+                rdev = regulator_register(&ri->desc, &config);
+                if (IS_ERR(rdev)) {
+                        dev_err(&pdev->dev, "Failed to register regulator %s\n",
+                                ri->desc.name);
+                        ret = PTR_ERR(rdev);
+                        goto eregreg;
+                }
+                reg->rdev = rdev;
+        }
+        platform_set_drvdata(pdev, regs);
+        return 0;
+
+eregreg:
+        while (--id >= 0)
+                regulator_unregister(regs[id].rdev);
+
+        return ret;
+}
+
+static int as3711_regulator_remove(struct platform_device *pdev)
+{
+        struct as3711_regulator *regs = platform_get_drvdata(pdev);
+        int id;
+
+        for (id = 0; id < AS3711_REGULATOR_NUM; ++id)
+                regulator_unregister(regs[id].rdev);
+        return 0;
+}
+
+static struct platform_driver as3711_regulator_driver = {
+        .driver = {
+                .name   = "as3711-regulator",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = as3711_regulator_probe,
+        .remove         = as3711_regulator_remove,
+};
+
+static int __init as3711_regulator_init(void)
+{
+        return platform_driver_register(&as3711_regulator_driver);
+}
+subsys_initcall(as3711_regulator_init);
+
+static void __exit as3711_regulator_exit(void)
+{
+        platform_driver_unregister(&as3711_regulator_driver);
+}
+module_exit(as3711_regulator_exit);
+
+MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
+MODULE_DESCRIPTION("AS3711 regulator driver");
+MODULE_ALIAS("platform:as3711-regulator");
+MODULE_LICENSE("GPL v2");