// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/arch/arm/mach-pxa/mfp-pxa2xx.c
 *
 *  PXA2xx pin mux configuration support
 *
 *  The GPIOs on PXA2xx can be configured as one of many alternate
 *  functions, this is by concept samilar to the MFP configuration
 *  on PXA3xx,  what's more important, the low power pin state and
 *  wakeup detection are also supported by the same framework.
 */
#include <linux/gpio.h>
#include <linux/gpio-pxa.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/syscore_ops.h>
#include <linux/soc/pxa/cpu.h>

#include "pxa2xx-regs.h"
#include "mfp-pxa2xx.h"
#include "mfp-pxa27x.h"

#include "generic.h"

#define PGSR(x)         __REG2(0x40F00020, (x) << 2)
#define __GAFR(u, x)    __REG2((u) ? 0x40E00058 : 0x40E00054, (x) << 3)
#define GAFR_L(x)       __GAFR(0, x)
#define GAFR_U(x)       __GAFR(1, x)

#define BANK_OFF(n)     (((n) < 3) ? (n) << 2 : 0x100 + (((n) - 3) << 2))
#define GPLR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5))
#define GPDR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x0c)
#define GPSR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x18)
#define GPCR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x24)

#define PWER_WE35       (1 << 24)

struct gpio_desc {
        unsigned        valid           : 1;
        unsigned        can_wakeup      : 1;
        unsigned        keypad_gpio     : 1;
        unsigned        dir_inverted    : 1;
        unsigned int    mask; /* bit mask in PWER or PKWR */
        unsigned int    mux_mask; /* bit mask of muxed gpio bits, 0 if no mux */
        unsigned long   config;
};

static struct gpio_desc gpio_desc[MFP_PIN_GPIO127 + 1];

static unsigned long gpdr_lpm[4];

static int __mfp_config_gpio(unsigned gpio, unsigned long c)
{
        unsigned long gafr, mask = GPIO_bit(gpio);
        int bank = gpio_to_bank(gpio);
        int uorl = !!(gpio & 0x10); /* GAFRx_U or GAFRx_L ? */
        int shft = (gpio & 0xf) << 1;
        int fn = MFP_AF(c);
        int is_out = (c & MFP_DIR_OUT) ? 1 : 0;

        if (fn > 3)
                return -EINVAL;

        /* alternate function and direction at run-time */
        gafr = (uorl == 0) ? GAFR_L(bank) : GAFR_U(bank);
        gafr = (gafr & ~(0x3 << shft)) | (fn << shft);

        if (uorl == 0)
                GAFR_L(bank) = gafr;
        else
                GAFR_U(bank) = gafr;

        if (is_out ^ gpio_desc[gpio].dir_inverted)
                GPDR(gpio) |= mask;
        else
                GPDR(gpio) &= ~mask;

        /* alternate function and direction at low power mode */
        switch (c & MFP_LPM_STATE_MASK) {
        case MFP_LPM_DRIVE_HIGH:
                PGSR(bank) |= mask;
                is_out = 1;
                break;
        case MFP_LPM_DRIVE_LOW:
                PGSR(bank) &= ~mask;
                is_out = 1;
                break;
        case MFP_LPM_INPUT:
        case MFP_LPM_DEFAULT:
                break;
        default:
                /* warning and fall through, treat as MFP_LPM_DEFAULT */
                pr_warn("%s: GPIO%d: unsupported low power mode\n",
                        __func__, gpio);
                break;
        }

        if (is_out ^ gpio_desc[gpio].dir_inverted)
                gpdr_lpm[bank] |= mask;
        else
                gpdr_lpm[bank] &= ~mask;

        /* give early warning if MFP_LPM_CAN_WAKEUP is set on the
         * configurations of those pins not able to wakeup
         */
        if ((c & MFP_LPM_CAN_WAKEUP) && !gpio_desc[gpio].can_wakeup) {
                pr_warn("%s: GPIO%d unable to wakeup\n", __func__, gpio);
                return -EINVAL;
        }

        if ((c & MFP_LPM_CAN_WAKEUP) && is_out) {
                pr_warn("%s: output GPIO%d unable to wakeup\n", __func__, gpio);
                return -EINVAL;
        }

        return 0;
}

static inline int __mfp_validate(int mfp)
{
        int gpio = mfp_to_gpio(mfp);

        if ((mfp > MFP_PIN_GPIO127) || !gpio_desc[gpio].valid) {
                pr_warn("%s: GPIO%d is invalid pin\n", __func__, gpio);
                return -1;
        }

        return gpio;
}

void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num)
{
        unsigned long flags;
        unsigned long *c;
        int i, gpio;

        for (i = 0, c = mfp_cfgs; i < num; i++, c++) {

                gpio = __mfp_validate(MFP_PIN(*c));
                if (gpio < 0)
                        continue;

                local_irq_save(flags);

                gpio_desc[gpio].config = *c;
                __mfp_config_gpio(gpio, *c);

                local_irq_restore(flags);
        }
}

void pxa2xx_mfp_set_lpm(int mfp, unsigned long lpm)
{
        unsigned long flags, c;
        int gpio;

        gpio = __mfp_validate(mfp);
        if (gpio < 0)
                return;

        local_irq_save(flags);

        c = gpio_desc[gpio].config;
        c = (c & ~MFP_LPM_STATE_MASK) | lpm;
        __mfp_config_gpio(gpio, c);

        local_irq_restore(flags);
}

int gpio_set_wake(unsigned int gpio, unsigned int on)
{
        struct gpio_desc *d;
        unsigned long c, mux_taken;

        if (gpio > mfp_to_gpio(MFP_PIN_GPIO127))
                return -EINVAL;

        d = &gpio_desc[gpio];
        c = d->config;

        if (!d->valid)
                return -EINVAL;

        /* Allow keypad GPIOs to wakeup system when
         * configured as generic GPIOs.
         */
        if (d->keypad_gpio && (MFP_AF(d->config) == 0) &&
            (d->config & MFP_LPM_CAN_WAKEUP)) {
                if (on)
                        PKWR |= d->mask;
                else
                        PKWR &= ~d->mask;
                return 0;
        }

        mux_taken = (PWER & d->mux_mask) & (~d->mask);
        if (on && mux_taken)
                return -EBUSY;

        if (d->can_wakeup && (c & MFP_LPM_CAN_WAKEUP)) {
                if (on) {
                        PWER = (PWER & ~d->mux_mask) | d->mask;

                        if (c & MFP_LPM_EDGE_RISE)
                                PRER |= d->mask;
                        else
                                PRER &= ~d->mask;

                        if (c & MFP_LPM_EDGE_FALL)
                                PFER |= d->mask;
                        else
                                PFER &= ~d->mask;
                } else {
                        PWER &= ~d->mask;
                        PRER &= ~d->mask;
                        PFER &= ~d->mask;
                }
        }
        return 0;
}

#ifdef CONFIG_PXA25x
static void __init pxa25x_mfp_init(void)
{
        int i;

        /* running before pxa_gpio_probe() */
        pxa_last_gpio = 84;
        for (i = 0; i <= pxa_last_gpio; i++)
                gpio_desc[i].valid = 1;

        for (i = 0; i <= 15; i++) {
                gpio_desc[i].can_wakeup = 1;
                gpio_desc[i].mask = GPIO_bit(i);
        }

        /* PXA26x has additional 4 GPIOs (86/87/88/89) which has the
         * direction bit inverted in GPDR2. See PXA26x DM 4.1.1.
         */
        for (i = 86; i <= pxa_last_gpio; i++)
                gpio_desc[i].dir_inverted = 1;
}
#else
static inline void pxa25x_mfp_init(void) {}
#endif /* CONFIG_PXA25x */

#ifdef CONFIG_PXA27x
static int pxa27x_pkwr_gpio[] = {
        13, 16, 17, 34, 36, 37, 38, 39, 90, 91, 93, 94,
        95, 96, 97, 98, 99, 100, 101, 102
};

int keypad_set_wake(unsigned int on)
{
        unsigned int i, gpio, mask = 0;
        struct gpio_desc *d;

        for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {

                gpio = pxa27x_pkwr_gpio[i];
                d = &gpio_desc[gpio];

                /* skip if configured as generic GPIO */
                if (MFP_AF(d->config) == 0)
                        continue;

                if (d->config & MFP_LPM_CAN_WAKEUP)
                        mask |= gpio_desc[gpio].mask;
        }

        if (on)
                PKWR |= mask;
        else
                PKWR &= ~mask;
        return 0;
}

#define PWER_WEMUX2_GPIO38      (1 << 16)
#define PWER_WEMUX2_GPIO53      (2 << 16)
#define PWER_WEMUX2_GPIO40      (3 << 16)
#define PWER_WEMUX2_GPIO36      (4 << 16)
#define PWER_WEMUX2_MASK        (7 << 16)
#define PWER_WEMUX3_GPIO31      (1 << 19)
#define PWER_WEMUX3_GPIO113     (2 << 19)
#define PWER_WEMUX3_MASK        (3 << 19)

#define INIT_GPIO_DESC_MUXED(mux, gpio)                         \
do {                                                            \
        gpio_desc[(gpio)].can_wakeup = 1;                       \
        gpio_desc[(gpio)].mask = PWER_ ## mux ## _GPIO ##gpio;  \
        gpio_desc[(gpio)].mux_mask = PWER_ ## mux ## _MASK;     \
} while (0)

static void __init pxa27x_mfp_init(void)
{
        int i, gpio;

        pxa_last_gpio = 120;    /* running before pxa_gpio_probe() */
        for (i = 0; i <= pxa_last_gpio; i++) {
                /* skip GPIO2, 5, 6, 7, 8, they are not
                 * valid pins allow configuration
                 */
                if (i == 2 || i == 5 || i == 6 || i == 7 || i == 8)
                        continue;

                gpio_desc[i].valid = 1;
        }

        /* Keypad GPIOs */
        for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
                gpio = pxa27x_pkwr_gpio[i];
                gpio_desc[gpio].can_wakeup = 1;
                gpio_desc[gpio].keypad_gpio = 1;
                gpio_desc[gpio].mask = 1 << i;
        }

        /* Overwrite GPIO13 as a PWER wakeup source */
        for (i = 0; i <= 15; i++) {
                /* skip GPIO2, 5, 6, 7, 8 */
                if (GPIO_bit(i) & 0x1e4)
                        continue;

                gpio_desc[i].can_wakeup = 1;
                gpio_desc[i].mask = GPIO_bit(i);
        }

        gpio_desc[35].can_wakeup = 1;
        gpio_desc[35].mask = PWER_WE35;

        INIT_GPIO_DESC_MUXED(WEMUX3, 31);
        INIT_GPIO_DESC_MUXED(WEMUX3, 113);
        INIT_GPIO_DESC_MUXED(WEMUX2, 38);
        INIT_GPIO_DESC_MUXED(WEMUX2, 53);
        INIT_GPIO_DESC_MUXED(WEMUX2, 40);
        INIT_GPIO_DESC_MUXED(WEMUX2, 36);
}
#else
static inline void pxa27x_mfp_init(void) {}
#endif /* CONFIG_PXA27x */

#ifdef CONFIG_PM
static unsigned long saved_gafr[2][4];
static unsigned long saved_gpdr[4];
static unsigned long saved_gplr[4];
static unsigned long saved_pgsr[4];

static int pxa2xx_mfp_suspend(void *data)
{
        int i;

        /* set corresponding PGSR bit of those marked MFP_LPM_KEEP_OUTPUT */
        for (i = 0; i < pxa_last_gpio; i++) {
                if ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
                    (GPDR(i) & GPIO_bit(i))) {
                        if (GPLR(i) & GPIO_bit(i))
                                PGSR(gpio_to_bank(i)) |= GPIO_bit(i);
                        else
                                PGSR(gpio_to_bank(i)) &= ~GPIO_bit(i);
                }
        }

        for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
                saved_gafr[0][i] = GAFR_L(i);
                saved_gafr[1][i] = GAFR_U(i);
                saved_gpdr[i] = GPDR(i * 32);
                saved_gplr[i] = GPLR(i * 32);
                saved_pgsr[i] = PGSR(i);

                GPSR(i * 32) = PGSR(i);
                GPCR(i * 32) = ~PGSR(i);
        }

        /* set GPDR bits taking into account MFP_LPM_KEEP_OUTPUT */
        for (i = 0; i < pxa_last_gpio; i++) {
                if ((gpdr_lpm[gpio_to_bank(i)] & GPIO_bit(i)) ||
                    ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
                     (saved_gpdr[gpio_to_bank(i)] & GPIO_bit(i))))
                        GPDR(i) |= GPIO_bit(i);
                else
                        GPDR(i) &= ~GPIO_bit(i);
        }

        return 0;
}

static void pxa2xx_mfp_resume(void *data)
{
        int i;

        for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
                GAFR_L(i) = saved_gafr[0][i];
                GAFR_U(i) = saved_gafr[1][i];
                GPSR(i * 32) = saved_gplr[i];
                GPCR(i * 32) = ~saved_gplr[i];
                GPDR(i * 32) = saved_gpdr[i];
                PGSR(i) = saved_pgsr[i];
        }
        PSSR = PSSR_RDH | PSSR_PH;
}
#else
#define pxa2xx_mfp_suspend      NULL
#define pxa2xx_mfp_resume       NULL
#endif

static const struct syscore_ops pxa2xx_mfp_syscore_ops = {
        .suspend        = pxa2xx_mfp_suspend,
        .resume         = pxa2xx_mfp_resume,
};

struct syscore pxa2xx_mfp_syscore = {
        .ops = &pxa2xx_mfp_syscore_ops,
};

static int __init pxa2xx_mfp_init(void)
{
        int i;

        if (!cpu_is_pxa2xx())
                return 0;

        if (cpu_is_pxa25x())
                pxa25x_mfp_init();

        if (cpu_is_pxa27x())
                pxa27x_mfp_init();

        /* clear RDH bit to enable GPIO receivers after reset/sleep exit */
        PSSR = PSSR_RDH;

        /* initialize gafr_run[], pgsr_lpm[] from existing values */
        for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++)
                gpdr_lpm[i] = GPDR(i * 32);

        return 0;
}
postcore_initcall(pxa2xx_mfp_init);