regulator: ab8500-ext: New driver to control external regulators

The ABx500 is capable of controlling three external regulator supplies.
Most commonly on and off are supported, but if an external regulator
chipset or power supply supports high-power and low-power mode settings,
we can control those too.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 394 insertions, 0 deletions

diff --git a/drivers/regulator/ab8500-ext.c b/drivers/regulator/ab8500-ext.c
new file mode 100644
index 000000000000..95008dec5190
--- /dev/null
+++ b/drivers/regulator/ab8500-ext.c
@@ -0,0 +1,394 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License v2
+ *
+ * Authors: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
+ *
+ * This file is based on drivers/regulator/ab8500.c
+ *
+ * AB8500 external regulators
+ *
+ * ab8500-ext supports the following regulators:
+ * - VextSupply3
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/mfd/abx500.h>
+#include <linux/mfd/abx500/ab8500.h>
+#include <linux/regulator/ab8500.h>
+
+/**
+ * struct ab8500_ext_regulator_info - ab8500 regulator information
+ * @dev: device pointer
+ * @desc: regulator description
+ * @rdev: regulator device
+ * @is_enabled: status of regulator (on/off)
+ * @update_bank: bank to control on/off
+ * @update_reg: register to control on/off
+ * @update_mask: mask to enable/disable and set mode of regulator
+ * @update_val: bits holding the regulator current mode
+ * @update_val_en: bits to set EN pin active (LPn pin deactive)
+ *                 normally this means high power mode
+ * @update_val_en_lp: bits to set EN pin active and LPn pin active
+ *                    normally this means low power mode
+ * @delay: startup delay in ms
+ */
+struct ab8500_ext_regulator_info {
+        struct device *dev;
+        struct regulator_desc desc;
+        struct regulator_dev *rdev;
+        bool is_enabled;
+        u8 update_bank;
+        u8 update_reg;
+        u8 update_mask;
+        u8 update_val;
+        u8 update_val_en;
+        u8 update_val_en_lp;
+};
+
+static int ab8500_ext_regulator_enable(struct regulator_dev *rdev)
+{
+        int ret;
+        struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+
+        if (info == NULL) {
+                dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+                return -EINVAL;
+        }
+
+        ret = abx500_mask_and_set_register_interruptible(info->dev,
+                info->update_bank, info->update_reg,
+                info->update_mask, info->update_val);
+        if (ret < 0)
+                dev_err(rdev_get_dev(info->rdev),
+                        "couldn't set enable bits for regulator\n");
+
+        info->is_enabled = true;
+
+        dev_dbg(rdev_get_dev(rdev), "%s-enable (bank, reg, mask, value):"
+                " 0x%02x, 0x%02x, 0x%02x, 0x%02x\n",
+                info->desc.name, info->update_bank, info->update_reg,
+                info->update_mask, info->update_val);
+
+        return ret;
+}
+
+static int ab8500_ext_regulator_disable(struct regulator_dev *rdev)
+{
+        int ret;
+        struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+
+        if (info == NULL) {
+                dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+                return -EINVAL;
+        }
+
+        ret = abx500_mask_and_set_register_interruptible(info->dev,
+                info->update_bank, info->update_reg,
+                info->update_mask, 0x0);
+        if (ret < 0)
+                dev_err(rdev_get_dev(info->rdev),
+                        "couldn't set disable bits for regulator\n");
+
+        info->is_enabled = false;
+
+        dev_dbg(rdev_get_dev(rdev), "%s-disable (bank, reg, mask, value):"
+                " 0x%02x, 0x%02x, 0x%02x, 0x%02x\n",
+                info->desc.name, info->update_bank, info->update_reg,
+                info->update_mask, 0x0);
+
+        return ret;
+}
+
+static int ab8500_ext_regulator_is_enabled(struct regulator_dev *rdev)
+{
+        int ret;
+        struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+        u8 regval;
+
+        if (info == NULL) {
+                dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+                return -EINVAL;
+        }
+
+        ret = abx500_get_register_interruptible(info->dev,
+                info->update_bank, info->update_reg, &regval);
+        if (ret < 0) {
+                dev_err(rdev_get_dev(rdev),
+                        "couldn't read 0x%x register\n", info->update_reg);
+                return ret;
+        }
+
+        dev_dbg(rdev_get_dev(rdev), "%s-is_enabled (bank, reg, mask, value):"
+                " 0x%02x, 0x%02x, 0x%02x, 0x%02x\n",
+                info->desc.name, info->update_bank, info->update_reg,
+                info->update_mask, regval);
+
+        if (regval & info->update_mask)
+                info->is_enabled = true;
+        else
+                info->is_enabled = false;
+
+        return info->is_enabled;
+}
+
+static int ab8500_ext_regulator_set_mode(struct regulator_dev *rdev,
+                                         unsigned int mode)
+{
+        int ret = 0;
+        struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+
+        if (info == NULL) {
+                dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+                return -EINVAL;
+        }
+
+        switch (mode) {
+        case REGULATOR_MODE_NORMAL:
+                info->update_val = info->update_val_hp;
+                break;
+        case REGULATOR_MODE_IDLE:
+                info->update_val = info->update_val_lp;
+                break;
+
+        default:
+                return -EINVAL;
+        }
+
+        if (info->is_enabled) {
+                u8 regval;
+
+                ret = enable(info, &regval);
+                if (ret < 0)
+                        dev_err(rdev_get_dev(rdev),
+                                "Could not set regulator mode.\n");
+
+                dev_dbg(rdev_get_dev(rdev),
+                        "%s-set_mode (bank, reg, mask, value): "
+                        "0x%x, 0x%x, 0x%x, 0x%x\n",
+                        info->desc.name, info->update_bank, info->update_reg,
+                        info->update_mask, regval);
+        }
+
+        return ret;
+}
+
+static unsigned int ab8500_ext_regulator_get_mode(struct regulator_dev *rdev)
+{
+        struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+        int ret;
+
+        if (info == NULL) {
+                dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+                return -EINVAL;
+        }
+
+        if (info->update_val == info->update_val_hp)
+                ret = REGULATOR_MODE_NORMAL;
+        else if (info->update_val == info->update_val_lp)
+                ret = REGULATOR_MODE_IDLE;
+        else
+                ret = -EINVAL;
+
+        return ret;
+}
+
+static int ab8500_ext_fixed_get_voltage(struct regulator_dev *rdev)
+{
+        struct regulation_constraints *regu_constraints = rdev->constraints;
+
+        if (regu_constraints == NULL) {
+                dev_err(rdev_get_dev(rdev), "regulator constraints null pointer\n");
+                return -EINVAL;
+        }
+        if (regu_constraints->min_uV && regu_constraints->max_uV) {
+                if (regu_constraints->min_uV == regu_constraints->max_uV)
+                        return regu_constraints->min_uV;
+        }
+        return -EINVAL;
+}
+
+static int ab8500_ext_list_voltage(struct regulator_dev *rdev,
+                                   unsigned selector)
+{
+        struct regulation_constraints *regu_constraints = rdev->constraints;
+
+        if (regu_constraints == NULL) {
+                dev_err(rdev_get_dev(rdev), "regulator constraints null pointer\n");
+                return -EINVAL;
+        }
+        /* return the uV for the fixed regulators */
+        if (regu_constraints->min_uV && regu_constraints->max_uV) {
+                if (regu_constraints->min_uV == regu_constraints->max_uV)
+                        return regu_constraints->min_uV;
+        }
+        return -EINVAL;
+}
+
+static struct regulator_ops ab8500_ext_regulator_ops = {
+        .enable                 = ab8500_ext_regulator_enable,
+        .disable                = ab8500_ext_regulator_disable,
+        .is_enabled             = ab8500_ext_regulator_is_enabled,
+        .set_mode               = ab8500_ext_regulator_set_mode,
+        .get_mode               = ab8500_ext_regulator_get_mode,
+        .get_voltage            = ab8500_ext_fixed_get_voltage,
+        .list_voltage           = ab8500_ext_list_voltage,
+};
+
+
+static struct ab8500_ext_regulator_info
+                ab8500_ext_regulator_info[AB8500_NUM_EXT_REGULATORS] = {
+        [AB8500_EXT_SUPPLY1] = {
+                .desc = {
+                        .name           = "VEXTSUPPLY1",
+                        .ops            = &ab8500_ext_regulator_ops,
+                        .type           = REGULATOR_VOLTAGE,
+                        .id             = AB8500_EXT_SUPPLY1,
+                        .owner          = THIS_MODULE,
+                        .n_voltages     = 1,
+                },
+                .update_bank            = 0x04,
+                .update_reg             = 0x08,
+                .update_mask            = 0x03,
+                .update_val             = 0x01,
+                .update_val_hp          = 0x01,
+                .update_val_lp          = 0x03,
+                .update_val_hw          = 0x02,
+        },
+        [AB8500_EXT_SUPPLY2] = {
+                .desc = {
+                        .name           = "VEXTSUPPLY2",
+                        .ops            = &ab8500_ext_regulator_ops,
+                        .type           = REGULATOR_VOLTAGE,
+                        .id             = AB8500_EXT_SUPPLY2,
+                        .owner          = THIS_MODULE,
+                        .n_voltages     = 1,
+                },
+                .update_bank            = 0x04,
+                .update_reg             = 0x08,
+                .update_mask            = 0x0c,
+                .update_val             = 0x04,
+                .update_val_hp          = 0x04,
+                .update_val_lp          = 0x0c,
+                .update_val_hw          = 0x08,
+        },
+        [AB8500_EXT_SUPPLY3] = {
+                .desc = {
+                        .name           = "VEXTSUPPLY3",
+                        .ops            = &ab8500_ext_regulator_ops,
+                        .type           = REGULATOR_VOLTAGE,
+                        .id             = AB8500_EXT_SUPPLY3,
+                        .owner          = THIS_MODULE,
+                        .n_voltages     = 1,
+                },
+                .update_bank            = 0x04,
+                .update_reg             = 0x08,
+                .update_mask            = 0x30,
+                .update_val             = 0x10,
+                .update_val_en          = 0x10,
+                .update_val_en_lp       = 0x30,
+        },
+};
+
+int ab8500_ext_regulator_init(struct platform_device *pdev)
+{
+        struct ab8500 *ab8500 = dev_get_drvdata(pdev->dev.parent);
+        struct ab8500_platform_data *ppdata;
+        struct ab8500_regulator_platform_data *pdata;
+        struct regulator_config config = { };
+        int i, err;
+
+        if (!ab8500) {
+                dev_err(&pdev->dev, "null mfd parent\n");
+                return -EINVAL;
+        }
+        ppdata = dev_get_platdata(ab8500->dev);
+        if (!ppdata) {
+                dev_err(&pdev->dev, "null parent pdata\n");
+                return -EINVAL;
+        }
+
+        pdata = ppdata->regulator;
+        if (!pdata) {
+                dev_err(&pdev->dev, "null pdata\n");
+                return -EINVAL;
+        }
+
+        /* make sure the platform data has the correct size */
+        if (pdata->num_ext_regulator != ARRAY_SIZE(ab8500_ext_regulator_info)) {
+                dev_err(&pdev->dev, "Configuration error: size mismatch.\n");
+                return -EINVAL;
+        }
+
+        /* check for AB8500 2.x */
+        if (abx500_get_chip_id(&pdev->dev) < 0x30) {
+                struct ab8500_ext_regulator_info *info;
+
+                /* VextSupply3LPn is inverted on AB8500 2.x */
+                info = &ab8500_ext_regulator_info[AB8500_EXT_SUPPLY3];
+                info->update_val = 0x30;
+                info->update_val_en = 0x30;
+                info->update_val_en_lp = 0x10;
+        }
+
+        /* register all regulators */
+        for (i = 0; i < ARRAY_SIZE(ab8500_ext_regulator_info); i++) {
+                struct ab8500_ext_regulator_info *info = NULL;
+
+                /* assign per-regulator data */
+                info = &ab8500_ext_regulator_info[i];
+                info->dev = &pdev->dev;
+
+                config.dev = &pdev->dev;
+                config.init_data = &pdata->ext_regulator[i];
+                config.driver_data = info;
+
+                /* register regulator with framework */
+                info->rdev = regulator_register(&info->desc, &config);
+
+                if (IS_ERR(info->rdev)) {
+                        err = PTR_ERR(info->rdev);
+                        dev_err(&pdev->dev, "failed to register regulator %s\n",
+                                        info->desc.name);
+                        /* when we fail, un-register all earlier regulators */
+                        while (--i >= 0) {
+                                info = &ab8500_ext_regulator_info[i];
+                                regulator_unregister(info->rdev);
+                        }
+                        return err;
+                }
+
+                dev_dbg(rdev_get_dev(info->rdev),
+                        "%s-probed\n", info->desc.name);
+        }
+
+        return 0;
+}
+
+int ab8500_ext_regulator_exit(struct platform_device *pdev)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(ab8500_ext_regulator_info); i++) {
+                struct ab8500_ext_regulator_info *info = NULL;
+                info = &ab8500_ext_regulator_info[i];
+
+                dev_vdbg(rdev_get_dev(info->rdev),
+                        "%s-remove\n", info->desc.name);
+
+                regulator_unregister(info->rdev);
+        }
+
+        return 0;
+}
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Bengt Jonsson <bengt.g.jonsson@stericsson.com>");
+MODULE_DESCRIPTION("AB8500 external regulator driver");
+MODULE_ALIAS("platform:ab8500-ext-regulator");