regulator: arizona: Add support for microphone supplies on Arizona devices

The Wolfson Arizona platform is used for a range of low power audio hub
CODECs. Many of these devices feature an integrated power supply for the
microphone which is supported by this driver.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 184 insertions, 0 deletions

diff --git a/drivers/regulator/arizona-micsupp.c b/drivers/regulator/arizona-micsupp.c
new file mode 100644
index 000000000000..97d85b09a940
--- /dev/null
+++ b/drivers/regulator/arizona-micsupp.c
@@ -0,0 +1,184 @@
+/*
+ * arizona-micsupp.c  --  Microphone supply for Arizona devices
+ *
+ * Copyright 2012 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+
+#include <linux/mfd/arizona/core.h>
+#include <linux/mfd/arizona/pdata.h>
+#include <linux/mfd/arizona/registers.h>
+
+#define ARIZONA_MICSUPP_MAX_SELECTOR 0x1f
+
+struct arizona_micsupp {
+        struct regulator_dev *regulator;
+        struct arizona *arizona;
+
+        struct regulator_consumer_supply supply;
+        struct regulator_init_data init_data;
+};
+
+static int arizona_micsupp_list_voltage(struct regulator_dev *rdev,
+                                        unsigned int selector)
+{
+        if (selector > ARIZONA_MICSUPP_MAX_SELECTOR)
+                return -EINVAL;
+
+        if (selector == ARIZONA_MICSUPP_MAX_SELECTOR)
+                return 3300000;
+        else
+                return (selector * 50000) + 1700000;
+}
+
+static int arizona_micsupp_map_voltage(struct regulator_dev *rdev,
+                                       int min_uV, int max_uV)
+{
+        unsigned int voltage;
+        int selector;
+
+        if (min_uV < 1700000)
+                min_uV = 1700000;
+
+        if (min_uV >= 3300000)
+                selector = ARIZONA_MICSUPP_MAX_SELECTOR;
+        else
+                selector = DIV_ROUND_UP(min_uV - 1700000, 50000);
+
+        if (selector < 0)
+                return -EINVAL;
+
+        voltage = arizona_micsupp_list_voltage(rdev, selector);
+        if (voltage < min_uV || voltage > max_uV)
+                return -EINVAL;
+
+        return selector;
+}
+
+static struct regulator_ops arizona_micsupp_ops = {
+        .enable = regulator_enable_regmap,
+        .disable = regulator_disable_regmap,
+        .is_enabled = regulator_is_enabled_regmap,
+
+        .list_voltage = arizona_micsupp_list_voltage,
+        .map_voltage = arizona_micsupp_map_voltage,
+
+        .get_voltage_sel = regulator_get_voltage_sel_regmap,
+        .set_voltage_sel = regulator_set_voltage_sel_regmap,
+};
+
+static const struct regulator_desc arizona_micsupp = {
+        .name = "MICVDD",
+        .supply_name = "CPVDD",
+        .type = REGULATOR_VOLTAGE,
+        .n_voltages = ARIZONA_MICSUPP_MAX_SELECTOR + 1,
+        .ops = &arizona_micsupp_ops,
+
+        .vsel_reg = ARIZONA_LDO2_CONTROL_1,
+        .vsel_mask = ARIZONA_LDO2_VSEL_MASK,
+        .enable_reg = ARIZONA_MIC_CHARGE_PUMP_1,
+        .enable_mask = ARIZONA_CPMIC_ENA,
+
+        .owner = THIS_MODULE,
+};
+
+static const struct regulator_init_data arizona_micsupp_default = {
+        .constraints = {
+                .valid_ops_mask = REGULATOR_CHANGE_STATUS |
+                                REGULATOR_CHANGE_VOLTAGE,
+                .min_uV = 1700000,
+                .max_uV = 3300000,
+        },
+
+        .num_consumer_supplies = 1,
+};
+
+static __devinit int arizona_micsupp_probe(struct platform_device *pdev)
+{
+        struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
+        struct regulator_config config = { };
+        struct arizona_micsupp *micsupp;
+        int ret;
+
+        micsupp = devm_kzalloc(&pdev->dev, sizeof(*micsupp), GFP_KERNEL);
+        if (micsupp == NULL) {
+                dev_err(&pdev->dev, "Unable to allocate private data\n");
+                return -ENOMEM;
+        }
+
+        micsupp->arizona = arizona;
+
+        /*
+         * Since the chip usually supplies itself we provide some
+         * default init_data for it.  This will be overridden with
+         * platform data if provided.
+         */
+        micsupp->init_data = arizona_micsupp_default;
+        micsupp->init_data.consumer_supplies = &micsupp->supply;
+        micsupp->supply.supply = "MICVDD";
+        micsupp->supply.dev_name = dev_name(arizona->dev);
+
+        config.dev = arizona->dev;
+        config.driver_data = micsupp;
+        config.regmap = arizona->regmap;
+
+        if (arizona->pdata.micvdd)
+                config.init_data = arizona->pdata.micvdd;
+        else
+                config.init_data = &micsupp->init_data;
+
+        micsupp->regulator = regulator_register(&arizona_micsupp, &config);
+        if (IS_ERR(micsupp->regulator)) {
+                ret = PTR_ERR(micsupp->regulator);
+                dev_err(arizona->dev, "Failed to register mic supply: %d\n",
+                        ret);
+                return ret;
+        }
+
+        platform_set_drvdata(pdev, micsupp);
+
+        return 0;
+}
+
+static __devexit int arizona_micsupp_remove(struct platform_device *pdev)
+{
+        struct arizona_micsupp *micsupp = platform_get_drvdata(pdev);
+
+        regulator_unregister(micsupp->regulator);
+
+        return 0;
+}
+
+static struct platform_driver arizona_micsupp_driver = {
+        .probe = arizona_micsupp_probe,
+        .remove = __devexit_p(arizona_micsupp_remove),
+        .driver         = {
+                .name   = "arizona-micsupp",
+                .owner  = THIS_MODULE,
+        },
+};
+
+module_platform_driver(arizona_micsupp_driver);
+
+/* Module information */
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("Arizona microphone supply driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:arizona-micsupp");