Merge remote-tracking branch 'regulator/topic/abb' into regulator-next

3 files changed, 921 insertions, 0 deletions

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 9744437afe32..f1e6ad98eeba 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -481,6 +481,16 @@ config REGULATOR_TWL4030
           This driver supports the voltage regulators provided by
           this family of companion chips.
 
+config REGULATOR_TI_ABB
+        bool "TI Adaptive Body Bias on-chip LDO"
+        depends on ARCH_OMAP
+        help
+          Select this option to support Texas Instruments' on-chip Adaptive Body
+          Bias (ABB) LDO regulators. It is recommended that this option be
+          enabled on required TI SoC. Certain Operating Performance Points
+          on TI SoCs may be unstable without enabling this as it provides
+          device specific optimized bias to allow/optimize functionality.
+
 config REGULATOR_VEXPRESS
         tristate "Versatile Express regulators"
         depends on VEXPRESS_CONFIG
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index c4b50fc7f44f..ba4a3cf3afec 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -64,6 +64,7 @@ obj-$(CONFIG_REGULATOR_TPS65910) += tps65910-regulator.o
 obj-$(CONFIG_REGULATOR_TPS65912) += tps65912-regulator.o
 obj-$(CONFIG_REGULATOR_TPS80031) += tps80031-regulator.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o
+obj-$(CONFIG_REGULATOR_TI_ABB) += ti-abb-regulator.o
 obj-$(CONFIG_REGULATOR_VEXPRESS) += vexpress.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o
diff --git a/drivers/regulator/ti-abb-regulator.c b/drivers/regulator/ti-abb-regulator.c
new file mode 100644
index 000000000000..3753ed05e719
--- /dev/null
+++ b/drivers/regulator/ti-abb-regulator.c
@@ -0,0 +1,910 @@
+/*
+ * Texas Instruments SoC Adaptive Body Bias(ABB) Regulator
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Mike Turquette <mturquette@ti.com>
+ *
+ * Copyright (C) 2012-2013 Texas Instruments, Inc.
+ * Andrii Tseglytskyi <andrii.tseglytskyi@ti.com>
+ * Nishanth Menon <nm@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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+
+/*
+ * ABB LDO operating states:
+ * NOMINAL_OPP: bypasses the ABB LDO
+ * FAST_OPP:    sets ABB LDO to Forward Body-Bias
+ * SLOW_OPP:    sets ABB LDO to Reverse Body-Bias
+ */
+#define TI_ABB_NOMINAL_OPP      0
+#define TI_ABB_FAST_OPP         1
+#define TI_ABB_SLOW_OPP         3
+
+/**
+ * struct ti_abb_info - ABB information per voltage setting
+ * @opp_sel:    one of TI_ABB macro
+ * @vset:       (optional) vset value that LDOVBB needs to be overriden with.
+ *
+ * Array of per voltage entries organized in the same order as regulator_desc's
+ * volt_table list. (selector is used to index from this array)
+ */
+struct ti_abb_info {
+        u32 opp_sel;
+        u32 vset;
+};
+
+/**
+ * struct ti_abb_reg - Register description for ABB block
+ * @setup_reg:                  setup register offset from base
+ * @control_reg:                control register offset from base
+ * @sr2_wtcnt_value_mask:       setup register- sr2_wtcnt_value mask
+ * @fbb_sel_mask:               setup register- FBB sel mask
+ * @rbb_sel_mask:               setup register- RBB sel mask
+ * @sr2_en_mask:                setup register- enable mask
+ * @opp_change_mask:            control register - mask to trigger LDOVBB change
+ * @opp_sel_mask:               control register - mask for mode to operate
+ */
+struct ti_abb_reg {
+        u32 setup_reg;
+        u32 control_reg;
+
+        /* Setup register fields */
+        u32 sr2_wtcnt_value_mask;
+        u32 fbb_sel_mask;
+        u32 rbb_sel_mask;
+        u32 sr2_en_mask;
+
+        /* Control register fields */
+        u32 opp_change_mask;
+        u32 opp_sel_mask;
+};
+
+/**
+ * struct ti_abb - ABB instance data
+ * @rdesc:                      regulator descriptor
+ * @clk:                        clock(usually sysclk) supplying ABB block
+ * @base:                       base address of ABB block
+ * @int_base:                   interrupt register base address
+ * @efuse_base:                 (optional) efuse base address for ABB modes
+ * @ldo_base:                   (optional) LDOVBB vset override base address
+ * @regs:                       pointer to struct ti_abb_reg for ABB block
+ * @txdone_mask:                mask on int_base for tranxdone interrupt
+ * @ldovbb_override_mask:       mask to ldo_base for overriding default LDO VBB
+ *                              vset with value from efuse
+ * @ldovbb_vset_mask:           mask to ldo_base for providing the VSET override
+ * @info:                       array to per voltage ABB configuration
+ * @current_info_idx:           current index to info
+ * @settling_time:              SoC specific settling time for LDO VBB
+ */
+struct ti_abb {
+        struct regulator_desc rdesc;
+        struct clk *clk;
+        void __iomem *base;
+        void __iomem *int_base;
+        void __iomem *efuse_base;
+        void __iomem *ldo_base;
+
+        const struct ti_abb_reg *regs;
+        u32 txdone_mask;
+        u32 ldovbb_override_mask;
+        u32 ldovbb_vset_mask;
+
+        struct ti_abb_info *info;
+        int current_info_idx;
+
+        u32 settling_time;
+};
+
+/**
+ * ti_abb_rmw() - handy wrapper to set specific register bits
+ * @mask:       mask for register field
+ * @value:      value shifted to mask location and written
+ * @offset:     offset of register
+ * @base:       base address
+ *
+ * Return: final register value (may be unused)
+ */
+static inline u32 ti_abb_rmw(u32 mask, u32 value, u32 offset,
+                             void __iomem *base)
+{
+        u32 val;
+
+        val = readl(base + offset);
+        val &= ~mask;
+        val |= (value << __ffs(mask)) & mask;
+        writel(val, base + offset);
+
+        return val;
+}
+
+/**
+ * ti_abb_check_txdone() - handy wrapper to check ABB tranxdone status
+ * @abb:        pointer to the abb instance
+ *
+ * Return: true or false
+ */
+static inline bool ti_abb_check_txdone(const struct ti_abb *abb)
+{
+        return !!(readl(abb->int_base) & abb->txdone_mask);
+}
+
+/**
+ * ti_abb_clear_txdone() - handy wrapper to clear ABB tranxdone status
+ * @abb:        pointer to the abb instance
+ */
+static inline void ti_abb_clear_txdone(const struct ti_abb *abb)
+{
+        writel(abb->txdone_mask, abb->int_base);
+};
+
+/**
+ * ti_abb_wait_tranx() - waits for ABB tranxdone event
+ * @dev:        device
+ * @abb:        pointer to the abb instance
+ *
+ * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
+ */
+static int ti_abb_wait_txdone(struct device *dev, struct ti_abb *abb)
+{
+        int timeout = 0;
+        bool status;
+
+        while (timeout++ <= abb->settling_time) {
+                status = ti_abb_check_txdone(abb);
+                if (status)
+                        break;
+
+                udelay(1);
+        }
+
+        if (timeout > abb->settling_time) {
+                dev_warn_ratelimited(dev,
+                                     "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
+                                     __func__, timeout, readl(abb->int_base));
+                return -ETIMEDOUT;
+        }
+
+        return 0;
+}
+
+/**
+ * ti_abb_clear_all_txdone() - clears ABB tranxdone event
+ * @dev:        device
+ * @abb:        pointer to the abb instance
+ *
+ * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
+ */
+static int ti_abb_clear_all_txdone(struct device *dev, const struct ti_abb *abb)
+{
+        int timeout = 0;
+        bool status;
+
+        while (timeout++ <= abb->settling_time) {
+                ti_abb_clear_txdone(abb);
+
+                status = ti_abb_check_txdone(abb);
+                if (!status)
+                        break;
+
+                udelay(1);
+        }
+
+        if (timeout > abb->settling_time) {
+                dev_warn_ratelimited(dev,
+                                     "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
+                                     __func__, timeout, readl(abb->int_base));
+                return -ETIMEDOUT;
+        }
+
+        return 0;
+}
+
+/**
+ * ti_abb_program_ldovbb() - program LDOVBB register for override value
+ * @dev:        device
+ * @abb:        pointer to the abb instance
+ * @info:       ABB info to program
+ */
+static void ti_abb_program_ldovbb(struct device *dev, const struct ti_abb *abb,
+                                  struct ti_abb_info *info)
+{
+        u32 val;
+
+        val = readl(abb->ldo_base);
+        /* clear up previous values */
+        val &= ~(abb->ldovbb_override_mask | abb->ldovbb_vset_mask);
+
+        switch (info->opp_sel) {
+        case TI_ABB_SLOW_OPP:
+        case TI_ABB_FAST_OPP:
+                val |= abb->ldovbb_override_mask;
+                val |= info->vset << __ffs(abb->ldovbb_vset_mask);
+                break;
+        }
+
+        writel(val, abb->ldo_base);
+}
+
+/**
+ * ti_abb_set_opp() - Setup ABB and LDO VBB for required bias
+ * @rdev:       regulator device
+ * @abb:        pointer to the abb instance
+ * @info:       ABB info to program
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_set_opp(struct regulator_dev *rdev, struct ti_abb *abb,
+                          struct ti_abb_info *info)
+{
+        const struct ti_abb_reg *regs = abb->regs;
+        struct device *dev = &rdev->dev;
+        int ret;
+
+        ret = ti_abb_clear_all_txdone(dev, abb);
+        if (ret)
+                goto out;
+
+        ti_abb_rmw(regs->fbb_sel_mask | regs->rbb_sel_mask, 0, regs->setup_reg,
+                   abb->base);
+
+        switch (info->opp_sel) {
+        case TI_ABB_SLOW_OPP:
+                ti_abb_rmw(regs->rbb_sel_mask, 1, regs->setup_reg, abb->base);
+                break;
+        case TI_ABB_FAST_OPP:
+                ti_abb_rmw(regs->fbb_sel_mask, 1, regs->setup_reg, abb->base);
+                break;
+        }
+
+        /* program next state of ABB ldo */
+        ti_abb_rmw(regs->opp_sel_mask, info->opp_sel, regs->control_reg,
+                   abb->base);
+
+        /* program LDO VBB vset override if needed */
+        if (abb->ldo_base)
+                ti_abb_program_ldovbb(dev, abb, info);
+
+        /* Initiate ABB ldo change */
+        ti_abb_rmw(regs->opp_change_mask, 1, regs->control_reg, abb->base);
+
+        /* Wait for ABB LDO to complete transition to new Bias setting */
+        ret = ti_abb_wait_txdone(dev, abb);
+        if (ret)
+                goto out;
+
+        ret = ti_abb_clear_all_txdone(dev, abb);
+        if (ret)
+                goto out;
+
+out:
+        return ret;
+}
+
+/**
+ * ti_abb_set_voltage_sel() - regulator accessor function to set ABB LDO
+ * @rdev:       regulator device
+ * @sel:        selector to index into required ABB LDO settings (maps to
+ *              regulator descriptor's volt_table)
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_set_voltage_sel(struct regulator_dev *rdev, unsigned sel)
+{
+        const struct regulator_desc *desc = rdev->desc;
+        struct ti_abb *abb = rdev_get_drvdata(rdev);
+        struct device *dev = &rdev->dev;
+        struct ti_abb_info *info, *oinfo;
+        int ret = 0;
+
+        if (!abb) {
+                dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
+                                    __func__);
+                return -ENODEV;
+        }
+
+        if (!desc->n_voltages || !abb->info) {
+                dev_err_ratelimited(dev,
+                                    "%s: No valid voltage table entries?\n",
+                                    __func__);
+                return -EINVAL;
+        }
+
+        if (sel >= desc->n_voltages) {
+                dev_err(dev, "%s: sel idx(%d) >= n_voltages(%d)\n", __func__,
+                        sel, desc->n_voltages);
+                return -EINVAL;
+        }
+
+        /* If we are in the same index as we were, nothing to do here! */
+        if (sel == abb->current_info_idx) {
+                dev_dbg(dev, "%s: Already at sel=%d\n", __func__, sel);
+                return ret;
+        }
+
+        /* If data is exactly the same, then just update index, no change */
+        info = &abb->info[sel];
+        oinfo = &abb->info[abb->current_info_idx];
+        if (!memcmp(info, oinfo, sizeof(*info))) {
+                dev_dbg(dev, "%s: Same data new idx=%d, old idx=%d\n", __func__,
+                        sel, abb->current_info_idx);
+                goto out;
+        }
+
+        ret = ti_abb_set_opp(rdev, abb, info);
+
+out:
+        if (!ret)
+                abb->current_info_idx = sel;
+        else
+                dev_err_ratelimited(dev,
+                                    "%s: Volt[%d] idx[%d] mode[%d] Fail(%d)\n",
+                                    __func__, desc->volt_table[sel], sel,
+                                    info->opp_sel, ret);
+        return ret;
+}
+
+/**
+ * ti_abb_get_voltage_sel() - Regulator accessor to get current ABB LDO setting
+ * @rdev:       regulator device
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_get_voltage_sel(struct regulator_dev *rdev)
+{
+        const struct regulator_desc *desc = rdev->desc;
+        struct ti_abb *abb = rdev_get_drvdata(rdev);
+        struct device *dev = &rdev->dev;
+
+        if (!abb) {
+                dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
+                                    __func__);
+                return -ENODEV;
+        }
+
+        if (!desc->n_voltages || !abb->info) {
+                dev_err_ratelimited(dev,
+                                    "%s: No valid voltage table entries?\n",
+                                    __func__);
+                return -EINVAL;
+        }
+
+        if (abb->current_info_idx >= (int)desc->n_voltages) {
+                dev_err(dev, "%s: Corrupted data? idx(%d) >= n_voltages(%d)\n",
+                        __func__, abb->current_info_idx, desc->n_voltages);
+                return -EINVAL;
+        }
+
+        return abb->current_info_idx;
+}
+
+/**
+ * ti_abb_init_timings() - setup ABB clock timing for the current platform
+ * @dev:        device
+ * @abb:        pointer to the abb instance
+ *
+ * Return: 0 if timing is updated, else returns error result.
+ */
+static int ti_abb_init_timings(struct device *dev, struct ti_abb *abb)
+{
+        u32 clock_cycles;
+        u32 clk_rate, sr2_wt_cnt_val, cycle_rate;
+        const struct ti_abb_reg *regs = abb->regs;
+        int ret;
+        char *pname = "ti,settling-time";
+
+        /* read device tree properties */
+        ret = of_property_read_u32(dev->of_node, pname, &abb->settling_time);
+        if (ret) {
+                dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
+                return ret;
+        }
+
+        /* ABB LDO cannot be settle in 0 time */
+        if (!abb->settling_time) {
+                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+                return -EINVAL;
+        }
+
+        pname = "ti,clock-cycles";
+        ret = of_property_read_u32(dev->of_node, pname, &clock_cycles);
+        if (ret) {
+                dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
+                return ret;
+        }
+        /* ABB LDO cannot be settle in 0 clock cycles */
+        if (!clock_cycles) {
+                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+                return -EINVAL;
+        }
+
+        abb->clk = devm_clk_get(dev, NULL);
+        if (IS_ERR(abb->clk)) {
+                ret = PTR_ERR(abb->clk);
+                dev_err(dev, "%s: Unable to get clk(%d)\n", __func__, ret);
+                return ret;
+        }
+
+        /*
+         * SR2_WTCNT_VALUE is the settling time for the ABB ldo after a
+         * transition and must be programmed with the correct time at boot.
+         * The value programmed into the register is the number of SYS_CLK
+         * clock cycles that match a given wall time profiled for the ldo.
+         * This value depends on:
+         * settling time of ldo in micro-seconds (varies per OMAP family)
+         * # of clock cycles per SYS_CLK period (varies per OMAP family)
+         * the SYS_CLK frequency in MHz (varies per board)
+         * The formula is:
+         *
+         *                      ldo settling time (in micro-seconds)
+         * SR2_WTCNT_VALUE = ------------------------------------------
+         *                   (# system clock cycles) * (sys_clk period)
+         *
+         * Put another way:
+         *
+         * SR2_WTCNT_VALUE = settling time / (# SYS_CLK cycles / SYS_CLK rate))
+         *
+         * To avoid dividing by zero multiply both "# clock cycles" and
+         * "settling time" by 10 such that the final result is the one we want.
+         */
+
+        /* Convert SYS_CLK rate to MHz & prevent divide by zero */
+        clk_rate = DIV_ROUND_CLOSEST(clk_get_rate(abb->clk), 1000000);
+
+        /* Calculate cycle rate */
+        cycle_rate = DIV_ROUND_CLOSEST(clock_cycles * 10, clk_rate);
+
+        /* Calulate SR2_WTCNT_VALUE */
+        sr2_wt_cnt_val = DIV_ROUND_CLOSEST(abb->settling_time * 10, cycle_rate);
+
+        dev_dbg(dev, "%s: Clk_rate=%ld, sr2_cnt=0x%08x\n", __func__,
+                clk_get_rate(abb->clk), sr2_wt_cnt_val);
+
+        ti_abb_rmw(regs->sr2_wtcnt_value_mask, sr2_wt_cnt_val, regs->setup_reg,
+                   abb->base);
+
+        return 0;
+}
+
+/**
+ * ti_abb_init_table() - Initialize ABB table from device tree
+ * @dev:        device
+ * @abb:        pointer to the abb instance
+ * @rinit_data: regulator initdata
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_init_table(struct device *dev, struct ti_abb *abb,
+                             struct regulator_init_data *rinit_data)
+{
+        struct ti_abb_info *info;
+        const struct property *prop;
+        const __be32 *abb_info;
+        const u32 num_values = 6;
+        char *pname = "ti,abb_info";
+        u32 num_entries, i;
+        unsigned int *volt_table;
+        int min_uV = INT_MAX, max_uV = 0;
+        struct regulation_constraints *c = &rinit_data->constraints;
+
+        prop = of_find_property(dev->of_node, pname, NULL);
+        if (!prop) {
+                dev_err(dev, "No '%s' property?\n", pname);
+                return -ENODEV;
+        }
+
+        if (!prop->value) {
+                dev_err(dev, "Empty '%s' property?\n", pname);
+                return -ENODATA;
+        }
+
+        /*
+         * Each abb_info is a set of n-tuple, where n is num_values, consisting
+         * of voltage and a set of detection logic for ABB information for that
+         * voltage to apply.
+         */
+        num_entries = prop->length / sizeof(u32);
+        if (!num_entries || (num_entries % num_values)) {
+                dev_err(dev, "All '%s' list entries need %d vals\n", pname,
+                        num_values);
+                return -EINVAL;
+        }
+        num_entries /= num_values;
+
+        info = devm_kzalloc(dev, sizeof(*info) * num_entries, GFP_KERNEL);
+        if (!info) {
+                dev_err(dev, "Can't allocate info table for '%s' property\n",
+                        pname);
+                return -ENOMEM;
+        }
+        abb->info = info;
+
+        volt_table = devm_kzalloc(dev, sizeof(unsigned int) * num_entries,
+                                  GFP_KERNEL);
+        if (!volt_table) {
+                dev_err(dev, "Can't allocate voltage table for '%s' property\n",
+                        pname);
+                return -ENOMEM;
+        }
+
+        abb->rdesc.n_voltages = num_entries;
+        abb->rdesc.volt_table = volt_table;
+        /* We do not know where the OPP voltage is at the moment */
+        abb->current_info_idx = -EINVAL;
+
+        abb_info = prop->value;
+        for (i = 0; i < num_entries; i++, info++, volt_table++) {
+                u32 efuse_offset, rbb_mask, fbb_mask, vset_mask;
+                u32 efuse_val;
+
+                /* NOTE: num_values should equal to entries picked up here */
+                *volt_table = be32_to_cpup(abb_info++);
+                info->opp_sel = be32_to_cpup(abb_info++);
+                efuse_offset = be32_to_cpup(abb_info++);
+                rbb_mask = be32_to_cpup(abb_info++);
+                fbb_mask = be32_to_cpup(abb_info++);
+                vset_mask = be32_to_cpup(abb_info++);
+
+                dev_dbg(dev,
+                        "[%d]v=%d ABB=%d ef=0x%x rbb=0x%x fbb=0x%x vset=0x%x\n",
+                        i, *volt_table, info->opp_sel, efuse_offset, rbb_mask,
+                        fbb_mask, vset_mask);
+
+                /* Find min/max for voltage set */
+                if (min_uV > *volt_table)
+                        min_uV = *volt_table;
+                if (max_uV < *volt_table)
+                        max_uV = *volt_table;
+
+                if (!abb->efuse_base) {
+                        /* Ignore invalid data, but warn to help cleanup */
+                        if (efuse_offset || rbb_mask || fbb_mask || vset_mask)
+                                dev_err(dev, "prop '%s': v=%d,bad efuse/mask\n",
+                                        pname, *volt_table);
+                        goto check_abb;
+                }
+
+                efuse_val = readl(abb->efuse_base + efuse_offset);
+
+                /* Use ABB recommendation from Efuse */
+                if (efuse_val & rbb_mask)
+                        info->opp_sel = TI_ABB_SLOW_OPP;
+                else if (efuse_val & fbb_mask)
+                        info->opp_sel = TI_ABB_FAST_OPP;
+                else if (rbb_mask || fbb_mask)
+                        info->opp_sel = TI_ABB_NOMINAL_OPP;
+
+                dev_dbg(dev,
+                        "[%d]v=%d efusev=0x%x final ABB=%d\n",
+                        i, *volt_table, efuse_val, info->opp_sel);
+
+                /* Use recommended Vset bits from Efuse */
+                if (!abb->ldo_base) {
+                        if (vset_mask)
+                                dev_err(dev, "prop'%s':v=%d vst=%x LDO base?\n",
+                                        pname, *volt_table, vset_mask);
+                        continue;
+                }
+                info->vset = efuse_val & vset_mask >> __ffs(vset_mask);
+                dev_dbg(dev, "[%d]v=%d vset=%x\n", i, *volt_table, info->vset);
+check_abb:
+                switch (info->opp_sel) {
+                case TI_ABB_NOMINAL_OPP:
+                case TI_ABB_FAST_OPP:
+                case TI_ABB_SLOW_OPP:
+                        /* Valid values */
+                        break;
+                default:
+                        dev_err(dev, "%s:[%d]v=%d, ABB=%d is invalid! Abort!\n",
+                                __func__, i, *volt_table, info->opp_sel);
+                        return -EINVAL;
+                }
+        }
+
+        /* Setup the min/max voltage constraints from the supported list */
+        c->min_uV = min_uV;
+        c->max_uV = max_uV;
+
+        return 0;
+}
+
+static struct regulator_ops ti_abb_reg_ops = {
+        .list_voltage = regulator_list_voltage_table,
+
+        .set_voltage_sel = ti_abb_set_voltage_sel,
+        .get_voltage_sel = ti_abb_get_voltage_sel,
+};
+
+/* Default ABB block offsets, IF this changes in future, create new one */
+static const struct ti_abb_reg abb_regs_v1 = {
+        /* WARNING: registers are wrongly documented in TRM */
+        .setup_reg              = 0x04,
+        .control_reg            = 0x00,
+
+        .sr2_wtcnt_value_mask   = (0xff << 8),
+        .fbb_sel_mask           = (0x01 << 2),
+        .rbb_sel_mask           = (0x01 << 1),
+        .sr2_en_mask            = (0x01 << 0),
+
+        .opp_change_mask        = (0x01 << 2),
+        .opp_sel_mask           = (0x03 << 0),
+};
+
+static const struct ti_abb_reg abb_regs_v2 = {
+        .setup_reg              = 0x00,
+        .control_reg            = 0x04,
+
+        .sr2_wtcnt_value_mask   = (0xff << 8),
+        .fbb_sel_mask           = (0x01 << 2),
+        .rbb_sel_mask           = (0x01 << 1),
+        .sr2_en_mask            = (0x01 << 0),
+
+        .opp_change_mask        = (0x01 << 2),
+        .opp_sel_mask           = (0x03 << 0),
+};
+
+static const struct of_device_id ti_abb_of_match[] = {
+        {.compatible = "ti,abb-v1", .data = &abb_regs_v1},
+        {.compatible = "ti,abb-v2", .data = &abb_regs_v2},
+        { },
+};
+
+MODULE_DEVICE_TABLE(of, ti_abb_of_match);
+
+/**
+ * ti_abb_probe() - Initialize an ABB ldo instance
+ * @pdev: ABB platform device
+ *
+ * Initializes an individual ABB LDO for required Body-Bias. ABB is used to
+ * addional bias supply to SoC modules for power savings or mandatory stability
+ * configuration at certain Operating Performance Points(OPPs).
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        const struct of_device_id *match;
+        struct resource *res;
+        struct ti_abb *abb;
+        struct regulator_init_data *initdata = NULL;
+        struct regulator_dev *rdev = NULL;
+        struct regulator_desc *desc;
+        struct regulation_constraints *c;
+        struct regulator_config config = { };
+        char *pname;
+        int ret = 0;
+
+        match = of_match_device(ti_abb_of_match, dev);
+        if (!match) {
+                /* We do not expect this to happen */
+                ret = -ENODEV;
+                dev_err(dev, "%s: Unable to match device\n", __func__);
+                goto err;
+        }
+        if (!match->data) {
+                ret = -EINVAL;
+                dev_err(dev, "%s: Bad data in match\n", __func__);
+                goto err;
+        }
+
+        abb = devm_kzalloc(dev, sizeof(struct ti_abb), GFP_KERNEL);
+        if (!abb) {
+                dev_err(dev, "%s: Unable to allocate ABB struct\n", __func__);
+                ret = -ENOMEM;
+                goto err;
+        }
+        abb->regs = match->data;
+
+        /* Map ABB resources */
+        pname = "base-address";
+        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+        if (!res) {
+                dev_err(dev, "Missing '%s' IO resource\n", pname);
+                ret = -ENODEV;
+                goto err;
+        }
+        abb->base = devm_ioremap_resource(dev, res);
+        if (IS_ERR(abb->base)) {
+                ret = PTR_ERR(abb->base);
+                goto err;
+        }
+
+        pname = "int-address";
+        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+        if (!res) {
+                dev_err(dev, "Missing '%s' IO resource\n", pname);
+                ret = -ENODEV;
+                goto err;
+        }
+        /*
+         * We may have shared interrupt register offsets which are
+         * write-1-to-clear between domains ensuring exclusivity.
+         */
+        abb->int_base = devm_ioremap_nocache(dev, res->start,
+                                             resource_size(res));
+        if (!abb->int_base) {
+                dev_err(dev, "Unable to map '%s'\n", pname);
+                ret = -ENOMEM;
+                goto err;
+        }
+
+        /* Map Optional resources */
+        pname = "efuse-address";
+        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+        if (!res) {
+                dev_dbg(dev, "Missing '%s' IO resource\n", pname);
+                ret = -ENODEV;
+                goto skip_opt;
+        }
+
+        /*
+         * We may have shared efuse register offsets which are read-only
+         * between domains
+         */
+        abb->efuse_base = devm_ioremap_nocache(dev, res->start,
+                                               resource_size(res));
+        if (!abb->efuse_base) {
+                dev_err(dev, "Unable to map '%s'\n", pname);
+                ret = -ENOMEM;
+                goto err;
+        }
+
+        pname = "ldo-address";
+        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+        if (!res) {
+                dev_dbg(dev, "Missing '%s' IO resource\n", pname);
+                ret = -ENODEV;
+                goto skip_opt;
+        }
+        abb->ldo_base = devm_ioremap_resource(dev, res);
+        if (IS_ERR(abb->ldo_base)) {
+                ret = PTR_ERR(abb->ldo_base);
+                goto err;
+        }
+
+        /* IF ldo_base is set, the following are mandatory */
+        pname = "ti,ldovbb-override-mask";
+        ret =
+            of_property_read_u32(pdev->dev.of_node, pname,
+                                 &abb->ldovbb_override_mask);
+        if (ret) {
+                dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
+                goto err;
+        }
+        if (!abb->ldovbb_override_mask) {
+                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+                ret = -EINVAL;
+                goto err;
+        }
+
+        pname = "ti,ldovbb-vset-mask";
+        ret =
+            of_property_read_u32(pdev->dev.of_node, pname,
+                                 &abb->ldovbb_vset_mask);
+        if (ret) {
+                dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
+                goto err;
+        }
+        if (!abb->ldovbb_vset_mask) {
+                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+                ret = -EINVAL;
+                goto err;
+        }
+
+skip_opt:
+        pname = "ti,tranxdone-status-mask";
+        ret =
+            of_property_read_u32(pdev->dev.of_node, pname,
+                                 &abb->txdone_mask);
+        if (ret) {
+                dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
+                goto err;
+        }
+        if (!abb->txdone_mask) {
+                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+                ret = -EINVAL;
+                goto err;
+        }
+
+        initdata = of_get_regulator_init_data(dev, pdev->dev.of_node);
+        if (!initdata) {
+                ret = -ENOMEM;
+                dev_err(dev, "%s: Unable to alloc regulator init data\n",
+                        __func__);
+                goto err;
+        }
+
+        /* init ABB opp_sel table */
+        ret = ti_abb_init_table(dev, abb, initdata);
+        if (ret)
+                goto err;
+
+        /* init ABB timing */
+        ret = ti_abb_init_timings(dev, abb);
+        if (ret)
+                goto err;
+
+        desc = &abb->rdesc;
+        desc->name = dev_name(dev);
+        desc->owner = THIS_MODULE;
+        desc->type = REGULATOR_VOLTAGE;
+        desc->ops = &ti_abb_reg_ops;
+
+        c = &initdata->constraints;
+        if (desc->n_voltages > 1)
+                c->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
+        c->always_on = true;
+
+        config.dev = dev;
+        config.init_data = initdata;
+        config.driver_data = abb;
+        config.of_node = pdev->dev.of_node;
+
+        rdev = regulator_register(desc, &config);
+        if (IS_ERR(rdev)) {
+                ret = PTR_ERR(rdev);
+                dev_err(dev, "%s: failed to register regulator(%d)\n",
+                        __func__, ret);
+                goto err;
+        }
+        platform_set_drvdata(pdev, rdev);
+
+        /* Enable the ldo if not already done by bootloader */
+        ti_abb_rmw(abb->regs->sr2_en_mask, 1, abb->regs->setup_reg, abb->base);
+
+        return 0;
+
+err:
+        dev_err(dev, "%s: Failed to initialize(%d)\n", __func__, ret);
+        return ret;
+}
+
+/**
+ * ti_abb_remove() - cleanups
+ * @pdev: ABB platform device
+ *
+ * Return: 0
+ */
+static int ti_abb_remove(struct platform_device *pdev)
+{
+        struct regulator_dev *rdev = platform_get_drvdata(pdev);
+
+        regulator_unregister(rdev);
+        return 0;
+}
+
+MODULE_ALIAS("platform:ti_abb");
+
+static struct platform_driver ti_abb_driver = {
+        .probe = ti_abb_probe,
+        .remove = ti_abb_remove,
+        .driver = {
+                   .name = "ti_abb",
+                   .owner = THIS_MODULE,
+                   .of_match_table = of_match_ptr(ti_abb_of_match),
+                   },
+};
+module_platform_driver(ti_abb_driver);
+
+MODULE_DESCRIPTION("Texas Instruments ABB LDO regulator driver");
+MODULE_AUTHOR("Texas Instruments Inc.");
+MODULE_LICENSE("GPL v2");