// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2013, Sony Mobile Communications AB.
 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
 */

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/slab.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/reboot.h>
#include <linux/pm.h>
#include <linux/log2.h>

#include "../core.h"
#include "../pinconf.h"
#include "pinctrl-msm.h"
#include "../pinctrl-utils.h"

#define MAX_NR_GPIO 300
#define MAX_NR_TILES 4
#define PS_HOLD_OFFSET 0x820

/**
 * struct msm_pinctrl - state for a pinctrl-msm device
 * @dev:            device handle.
 * @pctrl:          pinctrl handle.
 * @chip:           gpiochip handle.
 * @restart_nb:     restart notifier block.
 * @irq:            parent irq for the TLMM irq_chip.
 * @lock:           Spinlock to protect register resources as well
 *                  as msm_pinctrl data structures.
 * @enabled_irqs:   Bitmap of currently enabled irqs.
 * @dual_edge_irqs: Bitmap of irqs that need sw emulated dual edge
 *                  detection.
 * @soc;            Reference to soc_data of platform specific data.
 * @regs:           Base addresses for the TLMM tiles.
 */
struct msm_pinctrl {
        struct device *dev;
        struct pinctrl_dev *pctrl;
        struct gpio_chip chip;
        struct pinctrl_desc desc;
        struct notifier_block restart_nb;

        struct irq_chip irq_chip;
        int irq;

        raw_spinlock_t lock;

        DECLARE_BITMAP(dual_edge_irqs, MAX_NR_GPIO);
        DECLARE_BITMAP(enabled_irqs, MAX_NR_GPIO);

        const struct msm_pinctrl_soc_data *soc;
        void __iomem *regs[MAX_NR_TILES];
};

#define MSM_ACCESSOR(name) \
static u32 msm_readl_##name(struct msm_pinctrl *pctrl, \
                            const struct msm_pingroup *g) \
{ \
        return readl(pctrl->regs[g->tile] + g->name##_reg); \
} \
static void msm_writel_##name(u32 val, struct msm_pinctrl *pctrl, \
                              const struct msm_pingroup *g) \
{ \
        writel(val, pctrl->regs[g->tile] + g->name##_reg); \
}

MSM_ACCESSOR(ctl)
MSM_ACCESSOR(io)
MSM_ACCESSOR(intr_cfg)
MSM_ACCESSOR(intr_status)
MSM_ACCESSOR(intr_target)

static int msm_get_groups_count(struct pinctrl_dev *pctldev)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);

        return pctrl->soc->ngroups;
}

static const char *msm_get_group_name(struct pinctrl_dev *pctldev,
                                      unsigned group)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);

        return pctrl->soc->groups[group].name;
}

static int msm_get_group_pins(struct pinctrl_dev *pctldev,
                              unsigned group,
                              const unsigned **pins,
                              unsigned *num_pins)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);

        *pins = pctrl->soc->groups[group].pins;
        *num_pins = pctrl->soc->groups[group].npins;
        return 0;
}

static const struct pinctrl_ops msm_pinctrl_ops = {
        .get_groups_count       = msm_get_groups_count,
        .get_group_name         = msm_get_group_name,
        .get_group_pins         = msm_get_group_pins,
        .dt_node_to_map         = pinconf_generic_dt_node_to_map_group,
        .dt_free_map            = pinctrl_utils_free_map,
};

static int msm_pinmux_request(struct pinctrl_dev *pctldev, unsigned offset)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
        struct gpio_chip *chip = &pctrl->chip;

        return gpiochip_line_is_valid(chip, offset) ? 0 : -EINVAL;
}

static int msm_get_functions_count(struct pinctrl_dev *pctldev)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);

        return pctrl->soc->nfunctions;
}

static const char *msm_get_function_name(struct pinctrl_dev *pctldev,
                                         unsigned function)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);

        return pctrl->soc->functions[function].name;
}

static int msm_get_function_groups(struct pinctrl_dev *pctldev,
                                   unsigned function,
                                   const char * const **groups,
                                   unsigned * const num_groups)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);

        *groups = pctrl->soc->functions[function].groups;
        *num_groups = pctrl->soc->functions[function].ngroups;
        return 0;
}

static int msm_pinmux_set_mux(struct pinctrl_dev *pctldev,
                              unsigned function,
                              unsigned group)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
        const struct msm_pingroup *g;
        unsigned long flags;
        u32 val, mask;
        int i;

        g = &pctrl->soc->groups[group];
        mask = GENMASK(g->mux_bit + order_base_2(g->nfuncs) - 1, g->mux_bit);

        for (i = 0; i < g->nfuncs; i++) {
                if (g->funcs[i] == function)
                        break;
        }

        if (WARN_ON(i == g->nfuncs))
                return -EINVAL;

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        val = msm_readl_ctl(pctrl, g);
        val &= ~mask;
        val |= i << g->mux_bit;
        msm_writel_ctl(val, pctrl, g);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);

        return 0;
}

static int msm_pinmux_request_gpio(struct pinctrl_dev *pctldev,
                                   struct pinctrl_gpio_range *range,
                                   unsigned offset)
{
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
        const struct msm_pingroup *g = &pctrl->soc->groups[offset];

        /* No funcs? Probably ACPI so can't do anything here */
        if (!g->nfuncs)
                return 0;

        /* For now assume function 0 is GPIO because it always is */
        return msm_pinmux_set_mux(pctldev, g->funcs[0], offset);
}

static const struct pinmux_ops msm_pinmux_ops = {
        .request                = msm_pinmux_request,
        .get_functions_count    = msm_get_functions_count,
        .get_function_name      = msm_get_function_name,
        .get_function_groups    = msm_get_function_groups,
        .gpio_request_enable    = msm_pinmux_request_gpio,
        .set_mux                = msm_pinmux_set_mux,
};

static int msm_config_reg(struct msm_pinctrl *pctrl,
                          const struct msm_pingroup *g,
                          unsigned param,
                          unsigned *mask,
                          unsigned *bit)
{
        switch (param) {
        case PIN_CONFIG_BIAS_DISABLE:
        case PIN_CONFIG_BIAS_PULL_DOWN:
        case PIN_CONFIG_BIAS_BUS_HOLD:
        case PIN_CONFIG_BIAS_PULL_UP:
                *bit = g->pull_bit;
                *mask = 3;
                break;
        case PIN_CONFIG_DRIVE_STRENGTH:
                *bit = g->drv_bit;
                *mask = 7;
                break;
        case PIN_CONFIG_OUTPUT:
        case PIN_CONFIG_INPUT_ENABLE:
                *bit = g->oe_bit;
                *mask = 1;
                break;
        default:
                return -ENOTSUPP;
        }

        return 0;
}

#define MSM_NO_PULL             0
#define MSM_PULL_DOWN           1
#define MSM_KEEPER              2
#define MSM_PULL_UP_NO_KEEPER   2
#define MSM_PULL_UP             3

static unsigned msm_regval_to_drive(u32 val)
{
        return (val + 1) * 2;
}

static int msm_config_group_get(struct pinctrl_dev *pctldev,
                                unsigned int group,
                                unsigned long *config)
{
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
        unsigned param = pinconf_to_config_param(*config);
        unsigned mask;
        unsigned arg;
        unsigned bit;
        int ret;
        u32 val;

        g = &pctrl->soc->groups[group];

        ret = msm_config_reg(pctrl, g, param, &mask, &bit);
        if (ret < 0)
                return ret;

        val = msm_readl_ctl(pctrl, g);
        arg = (val >> bit) & mask;

        /* Convert register value to pinconf value */
        switch (param) {
        case PIN_CONFIG_BIAS_DISABLE:
                if (arg != MSM_NO_PULL)
                        return -EINVAL;
                arg = 1;
                break;
        case PIN_CONFIG_BIAS_PULL_DOWN:
                if (arg != MSM_PULL_DOWN)
                        return -EINVAL;
                arg = 1;
                break;
        case PIN_CONFIG_BIAS_BUS_HOLD:
                if (pctrl->soc->pull_no_keeper)
                        return -ENOTSUPP;

                if (arg != MSM_KEEPER)
                        return -EINVAL;
                arg = 1;
                break;
        case PIN_CONFIG_BIAS_PULL_UP:
                if (pctrl->soc->pull_no_keeper)
                        arg = arg == MSM_PULL_UP_NO_KEEPER;
                else
                        arg = arg == MSM_PULL_UP;
                if (!arg)
                        return -EINVAL;
                break;
        case PIN_CONFIG_DRIVE_STRENGTH:
                arg = msm_regval_to_drive(arg);
                break;
        case PIN_CONFIG_OUTPUT:
                /* Pin is not output */
                if (!arg)
                        return -EINVAL;

                val = msm_readl_io(pctrl, g);
                arg = !!(val & BIT(g->in_bit));
                break;
        case PIN_CONFIG_INPUT_ENABLE:
                /* Pin is output */
                if (arg)
                        return -EINVAL;
                arg = 1;
                break;
        default:
                return -ENOTSUPP;
        }

        *config = pinconf_to_config_packed(param, arg);

        return 0;
}

static int msm_config_group_set(struct pinctrl_dev *pctldev,
                                unsigned group,
                                unsigned long *configs,
                                unsigned num_configs)
{
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
        unsigned long flags;
        unsigned param;
        unsigned mask;
        unsigned arg;
        unsigned bit;
        int ret;
        u32 val;
        int i;

        g = &pctrl->soc->groups[group];

        for (i = 0; i < num_configs; i++) {
                param = pinconf_to_config_param(configs[i]);
                arg = pinconf_to_config_argument(configs[i]);

                ret = msm_config_reg(pctrl, g, param, &mask, &bit);
                if (ret < 0)
                        return ret;

                /* Convert pinconf values to register values */
                switch (param) {
                case PIN_CONFIG_BIAS_DISABLE:
                        arg = MSM_NO_PULL;
                        break;
                case PIN_CONFIG_BIAS_PULL_DOWN:
                        arg = MSM_PULL_DOWN;
                        break;
                case PIN_CONFIG_BIAS_BUS_HOLD:
                        if (pctrl->soc->pull_no_keeper)
                                return -ENOTSUPP;

                        arg = MSM_KEEPER;
                        break;
                case PIN_CONFIG_BIAS_PULL_UP:
                        if (pctrl->soc->pull_no_keeper)
                                arg = MSM_PULL_UP_NO_KEEPER;
                        else
                                arg = MSM_PULL_UP;
                        break;
                case PIN_CONFIG_DRIVE_STRENGTH:
                        /* Check for invalid values */
                        if (arg > 16 || arg < 2 || (arg % 2) != 0)
                                arg = -1;
                        else
                                arg = (arg / 2) - 1;
                        break;
                case PIN_CONFIG_OUTPUT:
                        /* set output value */
                        raw_spin_lock_irqsave(&pctrl->lock, flags);
                        val = msm_readl_io(pctrl, g);
                        if (arg)
                                val |= BIT(g->out_bit);
                        else
                                val &= ~BIT(g->out_bit);
                        msm_writel_io(val, pctrl, g);
                        raw_spin_unlock_irqrestore(&pctrl->lock, flags);

                        /* enable output */
                        arg = 1;
                        break;
                case PIN_CONFIG_INPUT_ENABLE:
                        /* disable output */
                        arg = 0;
                        break;
                default:
                        dev_err(pctrl->dev, "Unsupported config parameter: %x\n",
                                param);
                        return -EINVAL;
                }

                /* Range-check user-supplied value */
                if (arg & ~mask) {
                        dev_err(pctrl->dev, "config %x: %x is invalid\n", param, arg);
                        return -EINVAL;
                }

                raw_spin_lock_irqsave(&pctrl->lock, flags);
                val = msm_readl_ctl(pctrl, g);
                val &= ~(mask << bit);
                val |= arg << bit;
                msm_writel_ctl(val, pctrl, g);
                raw_spin_unlock_irqrestore(&pctrl->lock, flags);
        }

        return 0;
}

static const struct pinconf_ops msm_pinconf_ops = {
        .is_generic             = true,
        .pin_config_group_get   = msm_config_group_get,
        .pin_config_group_set   = msm_config_group_set,
};

static int msm_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
        unsigned long flags;
        u32 val;

        g = &pctrl->soc->groups[offset];

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        val = msm_readl_ctl(pctrl, g);
        val &= ~BIT(g->oe_bit);
        msm_writel_ctl(val, pctrl, g);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);

        return 0;
}

static int msm_gpio_direction_output(struct gpio_chip *chip, unsigned offset, int value)
{
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
        unsigned long flags;
        u32 val;

        g = &pctrl->soc->groups[offset];

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        val = msm_readl_io(pctrl, g);
        if (value)
                val |= BIT(g->out_bit);
        else
                val &= ~BIT(g->out_bit);
        msm_writel_io(val, pctrl, g);

        val = msm_readl_ctl(pctrl, g);
        val |= BIT(g->oe_bit);
        msm_writel_ctl(val, pctrl, g);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);

        return 0;
}

static int msm_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
{
        struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
        const struct msm_pingroup *g;
        u32 val;

        g = &pctrl->soc->groups[offset];

        val = msm_readl_ctl(pctrl, g);

        /* 0 = output, 1 = input */
        return val & BIT(g->oe_bit) ? 0 : 1;
}

static int msm_gpio_get(struct gpio_chip *chip, unsigned offset)
{
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
        u32 val;

        g = &pctrl->soc->groups[offset];

        val = msm_readl_io(pctrl, g);
        return !!(val & BIT(g->in_bit));
}

static void msm_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
        unsigned long flags;
        u32 val;

        g = &pctrl->soc->groups[offset];

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        val = msm_readl_io(pctrl, g);
        if (value)
                val |= BIT(g->out_bit);
        else
                val &= ~BIT(g->out_bit);
        msm_writel_io(val, pctrl, g);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);
}

#ifdef CONFIG_DEBUG_FS
#include <linux/seq_file.h>

static void msm_gpio_dbg_show_one(struct seq_file *s,
                                  struct pinctrl_dev *pctldev,
                                  struct gpio_chip *chip,
                                  unsigned offset,
                                  unsigned gpio)
{
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
        unsigned func;
        int is_out;
        int drive;
        int pull;
        int val;
        u32 ctl_reg, io_reg;

        static const char * const pulls_keeper[] = {
                "no pull",
                "pull down",
                "keeper",
                "pull up"
        };

        static const char * const pulls_no_keeper[] = {
                "no pull",
                "pull down",
                "pull up",
        };

        if (!gpiochip_line_is_valid(chip, offset))
                return;

        g = &pctrl->soc->groups[offset];
        ctl_reg = msm_readl_ctl(pctrl, g);
        io_reg = msm_readl_io(pctrl, g);

        is_out = !!(ctl_reg & BIT(g->oe_bit));
        func = (ctl_reg >> g->mux_bit) & 7;
        drive = (ctl_reg >> g->drv_bit) & 7;
        pull = (ctl_reg >> g->pull_bit) & 3;

        if (is_out)
                val = !!(io_reg & BIT(g->out_bit));
        else
                val = !!(io_reg & BIT(g->in_bit));

        seq_printf(s, " %-8s: %-3s", g->name, is_out ? "out" : "in");
        seq_printf(s, " %-4s func%d", val ? "high" : "low", func);
        seq_printf(s, " %dmA", msm_regval_to_drive(drive));
        if (pctrl->soc->pull_no_keeper)
                seq_printf(s, " %s", pulls_no_keeper[pull]);
        else
                seq_printf(s, " %s", pulls_keeper[pull]);
        seq_puts(s, "\n");
}

static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
        unsigned gpio = chip->base;
        unsigned i;

        for (i = 0; i < chip->ngpio; i++, gpio++)
                msm_gpio_dbg_show_one(s, NULL, chip, i, gpio);
}

#else
#define msm_gpio_dbg_show NULL
#endif

static int msm_gpio_init_valid_mask(struct gpio_chip *gc,
                                    unsigned long *valid_mask,
                                    unsigned int ngpios)
{
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        int ret;
        unsigned int len, i;
        const int *reserved = pctrl->soc->reserved_gpios;
        u16 *tmp;

        /* Driver provided reserved list overrides DT and ACPI */
        if (reserved) {
                bitmap_fill(valid_mask, ngpios);
                for (i = 0; reserved[i] >= 0; i++) {
                        if (i >= ngpios || reserved[i] >= ngpios) {
                                dev_err(pctrl->dev, "invalid list of reserved GPIOs\n");
                                return -EINVAL;
                        }
                        clear_bit(reserved[i], valid_mask);
                }

                return 0;
        }

        /* The number of GPIOs in the ACPI tables */
        len = ret = device_property_count_u16(pctrl->dev, "gpios");
        if (ret < 0)
                return 0;

        if (ret > ngpios)
                return -EINVAL;

        tmp = kmalloc_array(len, sizeof(*tmp), GFP_KERNEL);
        if (!tmp)
                return -ENOMEM;

        ret = device_property_read_u16_array(pctrl->dev, "gpios", tmp, len);
        if (ret < 0) {
                dev_err(pctrl->dev, "could not read list of GPIOs\n");
                goto out;
        }

        bitmap_zero(valid_mask, ngpios);
        for (i = 0; i < len; i++)
                set_bit(tmp[i], valid_mask);

out:
        kfree(tmp);
        return ret;
}

static const struct gpio_chip msm_gpio_template = {
        .direction_input  = msm_gpio_direction_input,
        .direction_output = msm_gpio_direction_output,
        .get_direction    = msm_gpio_get_direction,
        .get              = msm_gpio_get,
        .set              = msm_gpio_set,
        .request          = gpiochip_generic_request,
        .free             = gpiochip_generic_free,
        .dbg_show         = msm_gpio_dbg_show,
};

/* For dual-edge interrupts in software, since some hardware has no
 * such support:
 *
 * At appropriate moments, this function may be called to flip the polarity
 * settings of both-edge irq lines to try and catch the next edge.
 *
 * The attempt is considered successful if:
 * - the status bit goes high, indicating that an edge was caught, or
 * - the input value of the gpio doesn't change during the attempt.
 * If the value changes twice during the process, that would cause the first
 * test to fail but would force the second, as two opposite
 * transitions would cause a detection no matter the polarity setting.
 *
 * The do-loop tries to sledge-hammer closed the timing hole between
 * the initial value-read and the polarity-write - if the line value changes
 * during that window, an interrupt is lost, the new polarity setting is
 * incorrect, and the first success test will fail, causing a retry.
 *
 * Algorithm comes from Google's msmgpio driver.
 */
static void msm_gpio_update_dual_edge_pos(struct msm_pinctrl *pctrl,
                                          const struct msm_pingroup *g,
                                          struct irq_data *d)
{
        int loop_limit = 100;
        unsigned val, val2, intstat;
        unsigned pol;

        do {
                val = msm_readl_io(pctrl, g) & BIT(g->in_bit);

                pol = msm_readl_intr_cfg(pctrl, g);
                pol ^= BIT(g->intr_polarity_bit);
                msm_writel_intr_cfg(val, pctrl, g);

                val2 = msm_readl_io(pctrl, g) & BIT(g->in_bit);
                intstat = msm_readl_intr_status(pctrl, g);
                if (intstat || (val == val2))
                        return;
        } while (loop_limit-- > 0);
        dev_err(pctrl->dev, "dual-edge irq failed to stabilize, %#08x != %#08x\n",
                val, val2);
}

static void msm_gpio_irq_mask(struct irq_data *d)
{
        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        const struct msm_pingroup *g;
        unsigned long flags;
        u32 val;

        g = &pctrl->soc->groups[d->hwirq];

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        val = msm_readl_intr_cfg(pctrl, g);
        /*
         * There are two bits that control interrupt forwarding to the CPU. The
         * RAW_STATUS_EN bit causes the level or edge sensed on the line to be
         * latched into the interrupt status register when the hardware detects
         * an irq that it's configured for (either edge for edge type or level
         * for level type irq). The 'non-raw' status enable bit causes the
         * hardware to assert the summary interrupt to the CPU if the latched
         * status bit is set. There's a bug though, the edge detection logic
         * seems to have a problem where toggling the RAW_STATUS_EN bit may
         * cause the status bit to latch spuriously when there isn't any edge
         * so we can't touch that bit for edge type irqs and we have to keep
         * the bit set anyway so that edges are latched while the line is masked.
         *
         * To make matters more complicated, leaving the RAW_STATUS_EN bit
         * enabled all the time causes level interrupts to re-latch into the
         * status register because the level is still present on the line after
         * we ack it. We clear the raw status enable bit during mask here and
         * set the bit on unmask so the interrupt can't latch into the hardware
         * while it's masked.
         */
        if (irqd_get_trigger_type(d) & IRQ_TYPE_LEVEL_MASK)
                val &= ~BIT(g->intr_raw_status_bit);

        val &= ~BIT(g->intr_enable_bit);
        msm_writel_intr_cfg(val, pctrl, g);

        clear_bit(d->hwirq, pctrl->enabled_irqs);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);
}

static void msm_gpio_irq_clear_unmask(struct irq_data *d, bool status_clear)
{
        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        const struct msm_pingroup *g;
        unsigned long flags;
        u32 val;

        g = &pctrl->soc->groups[d->hwirq];

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        if (status_clear) {
                /*
                 * clear the interrupt status bit before unmask to avoid
                 * any erroneous interrupts that would have got latched
                 * when the interrupt is not in use.
                 */
                val = msm_readl_intr_status(pctrl, g);
                val &= ~BIT(g->intr_status_bit);
                msm_writel_intr_status(val, pctrl, g);
        }

        val = msm_readl_intr_cfg(pctrl, g);
        val |= BIT(g->intr_raw_status_bit);
        val |= BIT(g->intr_enable_bit);
        msm_writel_intr_cfg(val, pctrl, g);

        set_bit(d->hwirq, pctrl->enabled_irqs);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);
}

static void msm_gpio_irq_enable(struct irq_data *d)
{

        msm_gpio_irq_clear_unmask(d, true);
}

static void msm_gpio_irq_unmask(struct irq_data *d)
{
        msm_gpio_irq_clear_unmask(d, false);
}

static void msm_gpio_irq_ack(struct irq_data *d)
{
        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        const struct msm_pingroup *g;
        unsigned long flags;
        u32 val;

        g = &pctrl->soc->groups[d->hwirq];

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        val = msm_readl_intr_status(pctrl, g);
        if (g->intr_ack_high)
                val |= BIT(g->intr_status_bit);
        else
                val &= ~BIT(g->intr_status_bit);
        msm_writel_intr_status(val, pctrl, g);

        if (test_bit(d->hwirq, pctrl->dual_edge_irqs))
                msm_gpio_update_dual_edge_pos(pctrl, g, d);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);
}

static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        const struct msm_pingroup *g;
        unsigned long flags;
        u32 val;

        g = &pctrl->soc->groups[d->hwirq];

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        /*
         * For hw without possibility of detecting both edges
         */
        if (g->intr_detection_width == 1 && type == IRQ_TYPE_EDGE_BOTH)
                set_bit(d->hwirq, pctrl->dual_edge_irqs);
        else
                clear_bit(d->hwirq, pctrl->dual_edge_irqs);

        /* Route interrupts to application cpu */
        val = msm_readl_intr_target(pctrl, g);
        val &= ~(7 << g->intr_target_bit);
        val |= g->intr_target_kpss_val << g->intr_target_bit;
        msm_writel_intr_target(val, pctrl, g);

        /* Update configuration for gpio.
         * RAW_STATUS_EN is left on for all gpio irqs. Due to the
         * internal circuitry of TLMM, toggling the RAW_STATUS
         * could cause the INTR_STATUS to be set for EDGE interrupts.
         */
        val = msm_readl_intr_cfg(pctrl, g);
        val |= BIT(g->intr_raw_status_bit);
        if (g->intr_detection_width == 2) {
                val &= ~(3 << g->intr_detection_bit);
                val &= ~(1 << g->intr_polarity_bit);
                switch (type) {
                case IRQ_TYPE_EDGE_RISING:
                        val |= 1 << g->intr_detection_bit;
                        val |= BIT(g->intr_polarity_bit);
                        break;
                case IRQ_TYPE_EDGE_FALLING:
                        val |= 2 << g->intr_detection_bit;
                        val |= BIT(g->intr_polarity_bit);
                        break;
                case IRQ_TYPE_EDGE_BOTH:
                        val |= 3 << g->intr_detection_bit;
                        val |= BIT(g->intr_polarity_bit);
                        break;
                case IRQ_TYPE_LEVEL_LOW:
                        break;
                case IRQ_TYPE_LEVEL_HIGH:
                        val |= BIT(g->intr_polarity_bit);
                        break;
                }
        } else if (g->intr_detection_width == 1) {
                val &= ~(1 << g->intr_detection_bit);
                val &= ~(1 << g->intr_polarity_bit);
                switch (type) {
                case IRQ_TYPE_EDGE_RISING:
                        val |= BIT(g->intr_detection_bit);
                        val |= BIT(g->intr_polarity_bit);
                        break;
                case IRQ_TYPE_EDGE_FALLING:
                        val |= BIT(g->intr_detection_bit);
                        break;
                case IRQ_TYPE_EDGE_BOTH:
                        val |= BIT(g->intr_detection_bit);
                        val |= BIT(g->intr_polarity_bit);
                        break;
                case IRQ_TYPE_LEVEL_LOW:
                        break;
                case IRQ_TYPE_LEVEL_HIGH:
                        val |= BIT(g->intr_polarity_bit);
                        break;
                }
        } else {
                BUG();
        }
        msm_writel_intr_cfg(val, pctrl, g);

        if (test_bit(d->hwirq, pctrl->dual_edge_irqs))
                msm_gpio_update_dual_edge_pos(pctrl, g, d);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);

        if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
                irq_set_handler_locked(d, handle_level_irq);
        else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
                irq_set_handler_locked(d, handle_edge_irq);

        return 0;
}

static int msm_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
{
        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        unsigned long flags;

        raw_spin_lock_irqsave(&pctrl->lock, flags);

        irq_set_irq_wake(pctrl->irq, on);

        raw_spin_unlock_irqrestore(&pctrl->lock, flags);

        return 0;
}

static int msm_gpio_irq_reqres(struct irq_data *d)
{
        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        int ret;

        if (!try_module_get(gc->owner))
                return -ENODEV;

        ret = msm_pinmux_request_gpio(pctrl->pctrl, NULL, d->hwirq);
        if (ret)
                goto out;
        msm_gpio_direction_input(gc, d->hwirq);

        if (gpiochip_lock_as_irq(gc, d->hwirq)) {
                dev_err(gc->parent,
                        "unable to lock HW IRQ %lu for IRQ\n",
                        d->hwirq);
                ret = -EINVAL;
                goto out;
        }
        return 0;
out:
        module_put(gc->owner);
        return ret;
}

static void msm_gpio_irq_relres(struct irq_data *d)
{
        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);

        gpiochip_unlock_as_irq(gc, d->hwirq);
        module_put(gc->owner);
}

static void msm_gpio_irq_handler(struct irq_desc *desc)
{
        struct gpio_chip *gc = irq_desc_get_handler_data(desc);
        const struct msm_pingroup *g;
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        struct irq_chip *chip = irq_desc_get_chip(desc);
        int irq_pin;
        int handled = 0;
        u32 val;
        int i;

        chained_irq_enter(chip, desc);

        /*
         * Each pin has it's own IRQ status register, so use
         * enabled_irq bitmap to limit the number of reads.
         */
        for_each_set_bit(i, pctrl->enabled_irqs, pctrl->chip.ngpio) {
                g = &pctrl->soc->groups[i];
                val = msm_readl_intr_status(pctrl, g);
                if (val & BIT(g->intr_status_bit)) {
                        irq_pin = irq_find_mapping(gc->irq.domain, i);
                        generic_handle_irq(irq_pin);
                        handled++;
                }
        }

        /* No interrupts were flagged */
        if (handled == 0)
                handle_bad_irq(desc);

        chained_irq_exit(chip, desc);
}

static bool msm_gpio_needs_valid_mask(struct msm_pinctrl *pctrl)
{
        if (pctrl->soc->reserved_gpios)
                return true;

        return device_property_count_u16(pctrl->dev, "gpios") > 0;
}

static int msm_gpio_init(struct msm_pinctrl *pctrl)
{
        struct gpio_chip *chip;
        struct gpio_irq_chip *girq;
        int ret;
        unsigned ngpio = pctrl->soc->ngpios;

        if (WARN_ON(ngpio > MAX_NR_GPIO))
                return -EINVAL;

        chip = &pctrl->chip;
        chip->base = -1;
        chip->ngpio = ngpio;
        chip->label = dev_name(pctrl->dev);
        chip->parent = pctrl->dev;
        chip->owner = THIS_MODULE;
        chip->of_node = pctrl->dev->of_node;
        if (msm_gpio_needs_valid_mask(pctrl))
                chip->init_valid_mask = msm_gpio_init_valid_mask;

        pctrl->irq_chip.name = "msmgpio";
        pctrl->irq_chip.irq_enable = msm_gpio_irq_enable;
        pctrl->irq_chip.irq_mask = msm_gpio_irq_mask;
        pctrl->irq_chip.irq_unmask = msm_gpio_irq_unmask;
        pctrl->irq_chip.irq_ack = msm_gpio_irq_ack;
        pctrl->irq_chip.irq_set_type = msm_gpio_irq_set_type;
        pctrl->irq_chip.irq_set_wake = msm_gpio_irq_set_wake;
        pctrl->irq_chip.irq_request_resources = msm_gpio_irq_reqres;
        pctrl->irq_chip.irq_release_resources = msm_gpio_irq_relres;

        girq = &chip->irq;
        girq->chip = &pctrl->irq_chip;
        girq->parent_handler = msm_gpio_irq_handler;
        girq->num_parents = 1;
        girq->parents = devm_kcalloc(pctrl->dev, 1, sizeof(*girq->parents),
                                     GFP_KERNEL);
        if (!girq->parents)
                return -ENOMEM;
        girq->default_type = IRQ_TYPE_NONE;
        girq->handler = handle_bad_irq;
        girq->parents[0] = pctrl->irq;

        ret = gpiochip_add_data(&pctrl->chip, pctrl);
        if (ret) {
                dev_err(pctrl->dev, "Failed register gpiochip\n");
                return ret;
        }

        /*
         * For DeviceTree-supported systems, the gpio core checks the
         * pinctrl's device node for the "gpio-ranges" property.
         * If it is present, it takes care of adding the pin ranges
         * for the driver. In this case the driver can skip ahead.
         *
         * In order to remain compatible with older, existing DeviceTree
         * files which don't set the "gpio-ranges" property or systems that
         * utilize ACPI the driver has to call gpiochip_add_pin_range().
         */
        if (!of_property_read_bool(pctrl->dev->of_node, "gpio-ranges")) {
                ret = gpiochip_add_pin_range(&pctrl->chip,
                        dev_name(pctrl->dev), 0, 0, chip->ngpio);
                if (ret) {
                        dev_err(pctrl->dev, "Failed to add pin range\n");
                        gpiochip_remove(&pctrl->chip);
                        return ret;
                }
        }

        return 0;
}

static int msm_ps_hold_restart(struct notifier_block *nb, unsigned long action,
                               void *data)
{
        struct msm_pinctrl *pctrl = container_of(nb, struct msm_pinctrl, restart_nb);

        writel(0, pctrl->regs[0] + PS_HOLD_OFFSET);
        mdelay(1000);
        return NOTIFY_DONE;
}

static struct msm_pinctrl *poweroff_pctrl;

static void msm_ps_hold_poweroff(void)
{
        msm_ps_hold_restart(&poweroff_pctrl->restart_nb, 0, NULL);
}

static void msm_pinctrl_setup_pm_reset(struct msm_pinctrl *pctrl)
{
        int i;
        const struct msm_function *func = pctrl->soc->functions;

        for (i = 0; i < pctrl->soc->nfunctions; i++)
                if (!strcmp(func[i].name, "ps_hold")) {
                        pctrl->restart_nb.notifier_call = msm_ps_hold_restart;
                        pctrl->restart_nb.priority = 128;
                        if (register_restart_handler(&pctrl->restart_nb))
                                dev_err(pctrl->dev,
                                        "failed to setup restart handler.\n");
                        poweroff_pctrl = pctrl;
                        pm_power_off = msm_ps_hold_poweroff;
                        break;
                }
}

static __maybe_unused int msm_pinctrl_suspend(struct device *dev)
{
        struct msm_pinctrl *pctrl = dev_get_drvdata(dev);

        return pinctrl_force_sleep(pctrl->pctrl);
}

static __maybe_unused int msm_pinctrl_resume(struct device *dev)
{
        struct msm_pinctrl *pctrl = dev_get_drvdata(dev);

        return pinctrl_force_default(pctrl->pctrl);
}

SIMPLE_DEV_PM_OPS(msm_pinctrl_dev_pm_ops, msm_pinctrl_suspend,
                  msm_pinctrl_resume);

EXPORT_SYMBOL(msm_pinctrl_dev_pm_ops);

int msm_pinctrl_probe(struct platform_device *pdev,
                      const struct msm_pinctrl_soc_data *soc_data)
{
        struct msm_pinctrl *pctrl;
        struct resource *res;
        int ret;
        int i;

        pctrl = devm_kzalloc(&pdev->dev, sizeof(*pctrl), GFP_KERNEL);
        if (!pctrl)
                return -ENOMEM;

        pctrl->dev = &pdev->dev;
        pctrl->soc = soc_data;
        pctrl->chip = msm_gpio_template;

        raw_spin_lock_init(&pctrl->lock);

        if (soc_data->tiles) {
                for (i = 0; i < soc_data->ntiles; i++) {
                        res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
                                                           soc_data->tiles[i]);
                        pctrl->regs[i] = devm_ioremap_resource(&pdev->dev, res);
                        if (IS_ERR(pctrl->regs[i]))
                                return PTR_ERR(pctrl->regs[i]);
                }
        } else {
                res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
                pctrl->regs[0] = devm_ioremap_resource(&pdev->dev, res);
                if (IS_ERR(pctrl->regs[0]))
                        return PTR_ERR(pctrl->regs[0]);
        }

        msm_pinctrl_setup_pm_reset(pctrl);

        pctrl->irq = platform_get_irq(pdev, 0);
        if (pctrl->irq < 0)
                return pctrl->irq;

        pctrl->desc.owner = THIS_MODULE;
        pctrl->desc.pctlops = &msm_pinctrl_ops;
        pctrl->desc.pmxops = &msm_pinmux_ops;
        pctrl->desc.confops = &msm_pinconf_ops;
        pctrl->desc.name = dev_name(&pdev->dev);
        pctrl->desc.pins = pctrl->soc->pins;
        pctrl->desc.npins = pctrl->soc->npins;

        pctrl->pctrl = devm_pinctrl_register(&pdev->dev, &pctrl->desc, pctrl);
        if (IS_ERR(pctrl->pctrl)) {
                dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
                return PTR_ERR(pctrl->pctrl);
        }

        ret = msm_gpio_init(pctrl);
        if (ret)
                return ret;

        platform_set_drvdata(pdev, pctrl);

        dev_dbg(&pdev->dev, "Probed Qualcomm pinctrl driver\n");

        return 0;
}
EXPORT_SYMBOL(msm_pinctrl_probe);

int msm_pinctrl_remove(struct platform_device *pdev)
{
        struct msm_pinctrl *pctrl = platform_get_drvdata(pdev);

        gpiochip_remove(&pctrl->chip);

        unregister_restart_handler(&pctrl->restart_nb);

        return 0;
}
EXPORT_SYMBOL(msm_pinctrl_remove);