regulator: add new lp8788 regulator driver

TI LP8788 PMU has 4 BUCKS and 22 LDOs.
The voltage of BUCK1 and BUCK2 can be controlled by external gpios.
And some LDOs also can be enabled by external gpios.
The regmap interface is used for regulator operations.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 629 insertions, 0 deletions

diff --git a/drivers/regulator/lp8788-buck.c b/drivers/regulator/lp8788-buck.c
new file mode 100644
index 000000000000..6356e821400f
--- /dev/null
+++ b/drivers/regulator/lp8788-buck.c
@@ -0,0 +1,629 @@
+/*
+ * TI LP8788 MFD - buck regulator driver
+ *
+ * Copyright 2012 Texas Instruments
+ *
+ * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/mfd/lp8788.h>
+#include <linux/gpio.h>
+
+/* register address */
+#define LP8788_EN_BUCK                  0x0C
+#define LP8788_BUCK_DVS_SEL             0x1D
+#define LP8788_BUCK1_VOUT0              0x1E
+#define LP8788_BUCK1_VOUT1              0x1F
+#define LP8788_BUCK1_VOUT2              0x20
+#define LP8788_BUCK1_VOUT3              0x21
+#define LP8788_BUCK2_VOUT0              0x22
+#define LP8788_BUCK2_VOUT1              0x23
+#define LP8788_BUCK2_VOUT2              0x24
+#define LP8788_BUCK2_VOUT3              0x25
+#define LP8788_BUCK3_VOUT               0x26
+#define LP8788_BUCK4_VOUT               0x27
+#define LP8788_BUCK1_TIMESTEP           0x28
+#define LP8788_BUCK_PWM                 0x2D
+
+/* mask/shift bits */
+#define LP8788_EN_BUCK1_M               BIT(0)  /* Addr 0Ch */
+#define LP8788_EN_BUCK2_M               BIT(1)
+#define LP8788_EN_BUCK3_M               BIT(2)
+#define LP8788_EN_BUCK4_M               BIT(3)
+#define LP8788_BUCK1_DVS_SEL_M          0x04    /* Addr 1Dh */
+#define LP8788_BUCK1_DVS_M              0x03
+#define LP8788_BUCK1_DVS_S              0
+#define LP8788_BUCK2_DVS_SEL_M          0x40
+#define LP8788_BUCK2_DVS_M              0x30
+#define LP8788_BUCK2_DVS_S              4
+#define LP8788_BUCK1_DVS_I2C            BIT(2)
+#define LP8788_BUCK2_DVS_I2C            BIT(6)
+#define LP8788_BUCK1_DVS_PIN            (0 << 2)
+#define LP8788_BUCK2_DVS_PIN            (0 << 6)
+#define LP8788_VOUT_M                   0x1F    /* Addr 1Eh ~ 27h */
+#define LP8788_STARTUP_TIME_M           0xF8    /* Addr 28h ~ 2Bh */
+#define LP8788_STARTUP_TIME_S           3
+#define LP8788_FPWM_BUCK1_M             BIT(0)  /* Addr 2Dh */
+#define LP8788_FPWM_BUCK1_S             0
+#define LP8788_FPWM_BUCK2_M             BIT(1)
+#define LP8788_FPWM_BUCK2_S             1
+#define LP8788_FPWM_BUCK3_M             BIT(2)
+#define LP8788_FPWM_BUCK3_S             2
+#define LP8788_FPWM_BUCK4_M             BIT(3)
+#define LP8788_FPWM_BUCK4_S             3
+
+#define INVALID_ADDR                    0xFF
+#define LP8788_FORCE_PWM                1
+#define LP8788_AUTO_PWM                 0
+#define PIN_LOW                         0
+#define PIN_HIGH                        1
+#define ENABLE_TIME_USEC                32
+
+enum lp8788_dvs_state {
+        DVS_LOW  = GPIOF_OUT_INIT_LOW,
+        DVS_HIGH = GPIOF_OUT_INIT_HIGH,
+};
+
+enum lp8788_dvs_mode {
+        REGISTER,
+        EXTPIN,
+};
+
+enum lp8788_buck_id {
+        BUCK1,
+        BUCK2,
+        BUCK3,
+        BUCK4,
+};
+
+struct lp8788_pwm_map {
+        u8 mask;
+        u8 shift;
+};
+
+struct lp8788_buck {
+        struct lp8788 *lp;
+        struct regulator_dev *regulator;
+        struct lp8788_pwm_map *pmap;
+        void *dvs;
+};
+
+/* BUCK 1 ~ 4 voltage table */
+static const int lp8788_buck_vtbl[] = {
+         500000,  800000,  850000,  900000,  950000, 1000000, 1050000, 1100000,
+        1150000, 1200000, 1250000, 1300000, 1350000, 1400000, 1450000, 1500000,
+        1550000, 1600000, 1650000, 1700000, 1750000, 1800000, 1850000, 1900000,
+        1950000, 2000000,
+};
+
+/* buck pwm mode selection : used for set/get_mode in regulator ops
+ * @forced pwm : fast mode
+ * @auto pwm   : normal mode
+ */
+static struct lp8788_pwm_map buck_pmap[] = {
+        [BUCK1] = {
+                .mask = LP8788_FPWM_BUCK1_M,
+                .shift = LP8788_FPWM_BUCK1_S,
+        },
+        [BUCK2] = {
+                .mask = LP8788_FPWM_BUCK2_M,
+                .shift = LP8788_FPWM_BUCK2_S,
+        },
+        [BUCK3] = {
+                .mask = LP8788_FPWM_BUCK3_M,
+                .shift = LP8788_FPWM_BUCK3_S,
+        },
+        [BUCK4] = {
+                .mask = LP8788_FPWM_BUCK4_M,
+                .shift = LP8788_FPWM_BUCK4_S,
+        },
+};
+
+static const u8 buck1_vout_addr[] = {
+        LP8788_BUCK1_VOUT0, LP8788_BUCK1_VOUT1,
+        LP8788_BUCK1_VOUT2, LP8788_BUCK1_VOUT3,
+};
+
+static const u8 buck2_vout_addr[] = {
+        LP8788_BUCK2_VOUT0, LP8788_BUCK2_VOUT1,
+        LP8788_BUCK2_VOUT2, LP8788_BUCK2_VOUT3,
+};
+
+static void lp8788_buck1_set_dvs(struct lp8788_buck *buck)
+{
+        struct lp8788_buck1_dvs *dvs = (struct lp8788_buck1_dvs *)buck->dvs;
+        enum lp8788_dvs_state pinstate;
+
+        if (!dvs)
+                return;
+
+        pinstate = dvs->vsel == DVS_SEL_V0 ? DVS_LOW : DVS_HIGH;
+        if (gpio_is_valid(dvs->gpio))
+                gpio_set_value(dvs->gpio, pinstate);
+}
+
+static void lp8788_buck2_set_dvs(struct lp8788_buck *buck)
+{
+        struct lp8788_buck2_dvs *dvs = (struct lp8788_buck2_dvs *)buck->dvs;
+        enum lp8788_dvs_state pin1, pin2;
+
+        if (!dvs)
+                return;
+
+        switch (dvs->vsel) {
+        case DVS_SEL_V0:
+                pin1 = DVS_LOW;
+                pin2 = DVS_LOW;
+                break;
+        case DVS_SEL_V1:
+                pin1 = DVS_HIGH;
+                pin2 = DVS_LOW;
+                break;
+        case DVS_SEL_V2:
+                pin1 = DVS_LOW;
+                pin2 = DVS_HIGH;
+                break;
+        case DVS_SEL_V3:
+                pin1 = DVS_HIGH;
+                pin2 = DVS_HIGH;
+                break;
+        default:
+                return;
+        }
+
+        if (gpio_is_valid(dvs->gpio[0]))
+                gpio_set_value(dvs->gpio[0], pin1);
+
+        if (gpio_is_valid(dvs->gpio[1]))
+                gpio_set_value(dvs->gpio[1], pin2);
+}
+
+static void lp8788_set_dvs(struct lp8788_buck *buck, enum lp8788_buck_id id)
+{
+        switch (id) {
+        case BUCK1:
+                lp8788_buck1_set_dvs(buck);
+                break;
+        case BUCK2:
+                lp8788_buck2_set_dvs(buck);
+                break;
+        default:
+                break;
+        }
+}
+
+static enum lp8788_dvs_mode
+lp8788_get_buck_dvs_ctrl_mode(struct lp8788_buck *buck, enum lp8788_buck_id id)
+{
+        u8 val, mask;
+
+        switch (id) {
+        case BUCK1:
+                mask = LP8788_BUCK1_DVS_SEL_M;
+                break;
+        case BUCK2:
+                mask = LP8788_BUCK2_DVS_SEL_M;
+                break;
+        default:
+                return REGISTER;
+        }
+
+        lp8788_read_byte(buck->lp, LP8788_BUCK_DVS_SEL, &val);
+
+        return val & mask ? REGISTER : EXTPIN;
+}
+
+static bool lp8788_is_valid_buck_addr(u8 addr)
+{
+        switch (addr) {
+        case LP8788_BUCK1_VOUT0:
+        case LP8788_BUCK1_VOUT1:
+        case LP8788_BUCK1_VOUT2:
+        case LP8788_BUCK1_VOUT3:
+        case LP8788_BUCK2_VOUT0:
+        case LP8788_BUCK2_VOUT1:
+        case LP8788_BUCK2_VOUT2:
+        case LP8788_BUCK2_VOUT3:
+                return true;
+        default:
+                return false;
+        }
+}
+
+static u8 lp8788_select_buck_vout_addr(struct lp8788_buck *buck,
+                                        enum lp8788_buck_id id)
+{
+        enum lp8788_dvs_mode mode = lp8788_get_buck_dvs_ctrl_mode(buck, id);
+        struct lp8788_buck1_dvs *b1_dvs;
+        struct lp8788_buck2_dvs *b2_dvs;
+        u8 val, idx, addr;
+        int pin1, pin2;
+
+        switch (id) {
+        case BUCK1:
+                if (mode == EXTPIN) {
+                        b1_dvs = (struct lp8788_buck1_dvs *)buck->dvs;
+                        if (!b1_dvs)
+                                goto err;
+
+                        idx = gpio_get_value(b1_dvs->gpio) ? 1 : 0;
+                } else {
+                        lp8788_read_byte(buck->lp, LP8788_BUCK_DVS_SEL, &val);
+                        idx = (val & LP8788_BUCK1_DVS_M) >> LP8788_BUCK1_DVS_S;
+                }
+                addr = buck1_vout_addr[idx];
+                break;
+        case BUCK2:
+                if (mode == EXTPIN) {
+                        b2_dvs = (struct lp8788_buck2_dvs *)buck->dvs;
+                        if (!b2_dvs)
+                                goto err;
+
+                        pin1 = gpio_get_value(b2_dvs->gpio[0]);
+                        pin2 = gpio_get_value(b2_dvs->gpio[1]);
+
+                        if (pin1 == PIN_LOW && pin2 == PIN_LOW)
+                                idx = 0;
+                        else if (pin1 == PIN_LOW && pin2 == PIN_HIGH)
+                                idx = 2;
+                        else if (pin1 == PIN_HIGH && pin2 == PIN_LOW)
+                                idx = 1;
+                        else
+                                idx = 3;
+                } else {
+                        lp8788_read_byte(buck->lp, LP8788_BUCK_DVS_SEL, &val);
+                        idx = (val & LP8788_BUCK2_DVS_M) >> LP8788_BUCK2_DVS_S;
+                }
+                addr = buck2_vout_addr[idx];
+                break;
+        default:
+                goto err;
+        }
+
+        return addr;
+err:
+        return INVALID_ADDR;
+}
+
+static int lp8788_buck12_set_voltage_sel(struct regulator_dev *rdev,
+                                        unsigned selector)
+{
+        struct lp8788_buck *buck = rdev_get_drvdata(rdev);
+        enum lp8788_buck_id id = rdev_get_id(rdev);
+        u8 addr;
+
+        if (buck->dvs)
+                lp8788_set_dvs(buck, id);
+
+        addr = lp8788_select_buck_vout_addr(buck, id);
+        if (!lp8788_is_valid_buck_addr(addr))
+                return -EINVAL;
+
+        return lp8788_update_bits(buck->lp, addr, LP8788_VOUT_M, selector);
+}
+
+static int lp8788_buck12_get_voltage_sel(struct regulator_dev *rdev)
+{
+        struct lp8788_buck *buck = rdev_get_drvdata(rdev);
+        enum lp8788_buck_id id = rdev_get_id(rdev);
+        int ret;
+        u8 val, addr;
+
+        addr = lp8788_select_buck_vout_addr(buck, id);
+        if (!lp8788_is_valid_buck_addr(addr))
+                return -EINVAL;
+
+        ret = lp8788_read_byte(buck->lp, addr, &val);
+        if (ret)
+                return ret;
+
+        return val & LP8788_VOUT_M;
+}
+
+static int lp8788_buck_enable_time(struct regulator_dev *rdev)
+{
+        struct lp8788_buck *buck = rdev_get_drvdata(rdev);
+        enum lp8788_buck_id id = rdev_get_id(rdev);
+        u8 val, addr = LP8788_BUCK1_TIMESTEP + id;
+
+        if (lp8788_read_byte(buck->lp, addr, &val))
+                return -EINVAL;
+
+        val = (val & LP8788_STARTUP_TIME_M) >> LP8788_STARTUP_TIME_S;
+
+        return ENABLE_TIME_USEC * val;
+}
+
+static int lp8788_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+        struct lp8788_buck *buck = rdev_get_drvdata(rdev);
+        struct lp8788_pwm_map *pmap = buck->pmap;
+        u8 val;
+
+        if (!pmap)
+                return -EINVAL;
+
+        switch (mode) {
+        case REGULATOR_MODE_FAST:
+                val = LP8788_FORCE_PWM << pmap->shift;
+                break;
+        case REGULATOR_MODE_NORMAL:
+                val = LP8788_AUTO_PWM << pmap->shift;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        return lp8788_update_bits(buck->lp, LP8788_BUCK_PWM, pmap->mask, val);
+}
+
+static unsigned int lp8788_buck_get_mode(struct regulator_dev *rdev)
+{
+        struct lp8788_buck *buck = rdev_get_drvdata(rdev);
+        struct lp8788_pwm_map *pmap = buck->pmap;
+        u8 val;
+        int ret;
+
+        if (!pmap)
+                return -EINVAL;
+
+        ret = lp8788_read_byte(buck->lp, LP8788_BUCK_PWM, &val);
+        if (ret)
+                return ret;
+
+        return val & pmap->mask ? REGULATOR_MODE_FAST : REGULATOR_MODE_NORMAL;
+}
+
+static struct regulator_ops lp8788_buck12_ops = {
+        .list_voltage = regulator_list_voltage_table,
+        .set_voltage_sel = lp8788_buck12_set_voltage_sel,
+        .get_voltage_sel = lp8788_buck12_get_voltage_sel,
+        .enable = regulator_enable_regmap,
+        .disable = regulator_disable_regmap,
+        .is_enabled = regulator_is_enabled_regmap,
+        .enable_time = lp8788_buck_enable_time,
+        .set_mode = lp8788_buck_set_mode,
+        .get_mode = lp8788_buck_get_mode,
+};
+
+static struct regulator_ops lp8788_buck34_ops = {
+        .list_voltage = regulator_list_voltage_table,
+        .set_voltage_sel = regulator_set_voltage_sel_regmap,
+        .get_voltage_sel = regulator_get_voltage_sel_regmap,
+        .enable = regulator_enable_regmap,
+        .disable = regulator_disable_regmap,
+        .is_enabled = regulator_is_enabled_regmap,
+        .enable_time = lp8788_buck_enable_time,
+        .set_mode = lp8788_buck_set_mode,
+        .get_mode = lp8788_buck_get_mode,
+};
+
+static struct regulator_desc lp8788_buck_desc[] = {
+        {
+                .name = "buck1",
+                .id = BUCK1,
+                .ops = &lp8788_buck12_ops,
+                .n_voltages = ARRAY_SIZE(lp8788_buck_vtbl),
+                .volt_table = lp8788_buck_vtbl,
+                .type = REGULATOR_VOLTAGE,
+                .owner = THIS_MODULE,
+                .enable_reg = LP8788_EN_BUCK,
+                .enable_mask = LP8788_EN_BUCK1_M,
+        },
+        {
+                .name = "buck2",
+                .id = BUCK2,
+                .ops = &lp8788_buck12_ops,
+                .n_voltages = ARRAY_SIZE(lp8788_buck_vtbl),
+                .volt_table = lp8788_buck_vtbl,
+                .type = REGULATOR_VOLTAGE,
+                .owner = THIS_MODULE,
+                .enable_reg = LP8788_EN_BUCK,
+                .enable_mask = LP8788_EN_BUCK2_M,
+        },
+        {
+                .name = "buck3",
+                .id = BUCK3,
+                .ops = &lp8788_buck34_ops,
+                .n_voltages = ARRAY_SIZE(lp8788_buck_vtbl),
+                .volt_table = lp8788_buck_vtbl,
+                .type = REGULATOR_VOLTAGE,
+                .owner = THIS_MODULE,
+                .vsel_reg = LP8788_BUCK3_VOUT,
+                .vsel_mask = LP8788_VOUT_M,
+                .enable_reg = LP8788_EN_BUCK,
+                .enable_mask = LP8788_EN_BUCK3_M,
+        },
+        {
+                .name = "buck4",
+                .id = BUCK4,
+                .ops = &lp8788_buck34_ops,
+                .n_voltages = ARRAY_SIZE(lp8788_buck_vtbl),
+                .volt_table = lp8788_buck_vtbl,
+                .type = REGULATOR_VOLTAGE,
+                .owner = THIS_MODULE,
+                .vsel_reg = LP8788_BUCK4_VOUT,
+                .vsel_mask = LP8788_VOUT_M,
+                .enable_reg = LP8788_EN_BUCK,
+                .enable_mask = LP8788_EN_BUCK4_M,
+        },
+};
+
+static int lp8788_set_default_dvs_ctrl_mode(struct lp8788 *lp,
+                                        enum lp8788_buck_id id)
+{
+        u8 mask, val;
+
+        switch (id) {
+        case BUCK1:
+                mask = LP8788_BUCK1_DVS_SEL_M;
+                val  = LP8788_BUCK1_DVS_I2C;
+                break;
+        case BUCK2:
+                mask = LP8788_BUCK2_DVS_SEL_M;
+                val  = LP8788_BUCK2_DVS_I2C;
+                break;
+        default:
+                return 0;
+        }
+
+        return lp8788_update_bits(lp, LP8788_BUCK_DVS_SEL, mask, val);
+}
+
+static int _gpio_request(struct lp8788_buck *buck, int gpio, char *name)
+{
+        struct device *dev = buck->lp->dev;
+
+        if (!gpio_is_valid(gpio)) {
+                dev_err(dev, "invalid gpio: %d\n", gpio);
+                return -EINVAL;
+        }
+
+        return devm_gpio_request_one(dev, gpio, DVS_LOW, name);
+}
+
+static int lp8788_dvs_gpio_request(struct lp8788_buck *buck,
+                                enum lp8788_buck_id id)
+{
+        struct lp8788_platform_data *pdata = buck->lp->pdata;
+        char *b1_name = "LP8788_B1_DVS";
+        char *b2_name[] = { "LP8788_B2_DVS1", "LP8788_B2_DVS2" };
+        int i, gpio, ret;
+
+        switch (id) {
+        case BUCK1:
+                gpio = pdata->buck1_dvs->gpio;
+                ret = _gpio_request(buck, gpio, b1_name);
+                if (ret)
+                        return ret;
+
+                buck->dvs = pdata->buck1_dvs;
+                break;
+        case BUCK2:
+                for (i = 0 ; i < LP8788_NUM_BUCK2_DVS ; i++) {
+                        gpio = pdata->buck2_dvs->gpio[i];
+                        ret = _gpio_request(buck, gpio, b2_name[i]);
+                        if (ret)
+                                return ret;
+                }
+                buck->dvs = pdata->buck2_dvs;
+                break;
+        default:
+                break;
+        }
+
+        return 0;
+}
+
+static int lp8788_init_dvs(struct lp8788_buck *buck, enum lp8788_buck_id id)
+{
+        struct lp8788_platform_data *pdata = buck->lp->pdata;
+        u8 mask[] = { LP8788_BUCK1_DVS_SEL_M, LP8788_BUCK2_DVS_SEL_M };
+        u8 val[]  = { LP8788_BUCK1_DVS_PIN, LP8788_BUCK2_DVS_PIN };
+
+        /* no dvs for buck3, 4 */
+        if (id == BUCK3 || id == BUCK4)
+                return 0;
+
+        /* no dvs platform data, then dvs will be selected by I2C registers */
+        if (!pdata)
+                goto set_default_dvs_mode;
+
+        if ((id == BUCK1 && !pdata->buck1_dvs) ||
+                (id == BUCK2 && !pdata->buck2_dvs))
+                goto set_default_dvs_mode;
+
+        if (lp8788_dvs_gpio_request(buck, id))
+                goto set_default_dvs_mode;
+
+        return lp8788_update_bits(buck->lp, LP8788_BUCK_DVS_SEL, mask[id],
+                                val[id]);
+
+set_default_dvs_mode:
+        return lp8788_set_default_dvs_ctrl_mode(buck->lp, id);
+}
+
+static __devinit int lp8788_buck_probe(struct platform_device *pdev)
+{
+        struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
+        int id = pdev->id;
+        struct lp8788_buck *buck;
+        struct regulator_config cfg = { };
+        struct regulator_dev *rdev;
+        int ret;
+
+        buck = devm_kzalloc(lp->dev, sizeof(struct lp8788_buck), GFP_KERNEL);
+        if (!buck)
+                return -ENOMEM;
+
+        buck->lp = lp;
+        buck->pmap = &buck_pmap[id];
+
+        ret = lp8788_init_dvs(buck, id);
+        if (ret)
+                return ret;
+
+        cfg.dev = lp->dev;
+        cfg.init_data = lp->pdata ? lp->pdata->buck_data[id] : NULL;
+        cfg.driver_data = buck;
+        cfg.regmap = lp->regmap;
+
+        rdev = regulator_register(&lp8788_buck_desc[id], &cfg);
+        if (IS_ERR(rdev)) {
+                ret = PTR_ERR(rdev);
+                dev_err(lp->dev, "BUCK%d regulator register err = %d\n",
+                                id + 1, ret);
+                return ret;
+        }
+
+        buck->regulator = rdev;
+        platform_set_drvdata(pdev, buck);
+
+        return 0;
+}
+
+static int __devexit lp8788_buck_remove(struct platform_device *pdev)
+{
+        struct lp8788_buck *buck = platform_get_drvdata(pdev);
+
+        platform_set_drvdata(pdev, NULL);
+        regulator_unregister(buck->regulator);
+
+        return 0;
+}
+
+static struct platform_driver lp8788_buck_driver = {
+        .probe = lp8788_buck_probe,
+        .remove = __devexit_p(lp8788_buck_remove),
+        .driver = {
+                .name = LP8788_DEV_BUCK,
+                .owner = THIS_MODULE,
+        },
+};
+
+static int __init lp8788_buck_init(void)
+{
+        return platform_driver_register(&lp8788_buck_driver);
+}
+subsys_initcall(lp8788_buck_init);
+
+static void __exit lp8788_buck_exit(void)
+{
+        platform_driver_unregister(&lp8788_buck_driver);
+}
+module_exit(lp8788_buck_exit);
+
+MODULE_DESCRIPTION("TI LP8788 BUCK Driver");
+MODULE_AUTHOR("Milo Kim");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:lp8788-buck");