/*      $OpenBSD: pca9554.c,v 1.19 2022/04/06 18:59:28 naddy Exp $      */

/*
 * Copyright (c) 2005 Theo de Raadt
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>

#include <dev/i2c/i2cvar.h>

#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_gpio.h>

/* Philips 9554/6/7 registers */
#define PCA9554_IN              0x00
#define PCA9554_OUT             0x01
#define PCA9554_POLARITY        0x02
#define PCA9554_CONFIG          0x03

/* Philips 9555 registers */
#define PCA9555_IN0             0x00
#define PCA9555_IN1             0x01
#define PCA9555_OUT0            0x02
#define PCA9555_OUT1            0x03
#define PCA9555_POLARITY0       0x04
#define PCA9555_POLARITY1       0x05
#define PCA9555_CONFIG0         0x06
#define PCA9555_CONFIG1         0x07

/* Sensors */
#define PCAGPIO_NPINS   16

#define PCAGPIO_NPORTS  2
#define PCAGPIO_PORT(_pin)      ((_pin) > 7 ? 1 : 0)
#define PCAGPIO_BIT(_pin)       (1 << ((_pin) % 8))

/* Register mapping index */
enum pcigpio_cmd {
        PCAGPIO_IN              = 0,
        PCAGPIO_OUT,
        PCAGPIO_POLARITY,
        PCAGPIO_CONFIG,
        PCAGPIO_MAX
};

struct pcagpio_softc {
        struct device   sc_dev;
        i2c_tag_t       sc_tag;
        i2c_addr_t      sc_addr;
        int             sc_node;

        u_int8_t        sc_npins;
        u_int8_t        sc_regs[PCAGPIO_NPORTS][PCAGPIO_MAX];

        struct gpio_controller sc_gc;
};

int     pcagpio_match(struct device *, void *, void *);
void    pcagpio_attach(struct device *, struct device *, void *);
int     pcagpio_init(struct pcagpio_softc *, int);

void    pcagpio_config_pin(void *, uint32_t *, int);
int     pcagpio_get_pin(void *, uint32_t *);
void    pcagpio_set_pin(void *, uint32_t *, int);

const struct cfattach pcagpio_ca = {
        sizeof(struct pcagpio_softc), pcagpio_match, pcagpio_attach
};

struct cfdriver pcagpio_cd = {
        NULL, "pcagpio", DV_DULL
};

int
pcagpio_match(struct device *parent, void *match, void *aux)
{
        struct i2c_attach_args *ia = aux;

        if (strcmp(ia->ia_name, "nxp,pca9554") == 0 ||
            strcmp(ia->ia_name, "nxp,pca9555") == 0 ||
            strcmp(ia->ia_name, "nxp,pca9557") == 0)
                return (1);
        return (0);
}

void
pcagpio_attach(struct device *parent, struct device *self, void *aux)
{
        struct pcagpio_softc *sc = (struct pcagpio_softc *)self;
        struct i2c_attach_args *ia = aux;

        sc->sc_tag = ia->ia_tag;
        sc->sc_addr = ia->ia_addr;
        sc->sc_node = *(int *)ia->ia_cookie;

        if (strcmp(ia->ia_name, "nxp,pca9555") == 0) {
                /* The pca9555 has two 8 bit ports */
                sc->sc_regs[0][PCAGPIO_IN] = PCA9555_IN0;
                sc->sc_regs[0][PCAGPIO_OUT] = PCA9555_OUT0;
                sc->sc_regs[0][PCAGPIO_POLARITY] = PCA9555_POLARITY0;
                sc->sc_regs[0][PCAGPIO_CONFIG] = PCA9555_CONFIG0;
                sc->sc_regs[1][PCAGPIO_IN] = PCA9555_IN1;
                sc->sc_regs[1][PCAGPIO_OUT] = PCA9555_OUT1;
                sc->sc_regs[1][PCAGPIO_POLARITY] = PCA9555_POLARITY1;
                sc->sc_regs[1][PCAGPIO_CONFIG] = PCA9555_CONFIG1;
                sc->sc_npins = 16;
        } else {
                /* All other supported devices have one 8 bit port */
                sc->sc_regs[0][PCAGPIO_IN] = PCA9554_IN;
                sc->sc_regs[0][PCAGPIO_OUT] = PCA9554_OUT;
                sc->sc_regs[0][PCAGPIO_POLARITY] = PCA9554_POLARITY;
                sc->sc_regs[0][PCAGPIO_CONFIG] = PCA9554_CONFIG;
                sc->sc_npins = 8;
        }
        if (pcagpio_init(sc, 0) != 0)
                return;
        if (sc->sc_npins > 8 && pcagpio_init(sc, 1) != 0)
                return;

        printf("\n");

        /* Create controller tag */
        sc->sc_gc.gc_node = sc->sc_node;
        sc->sc_gc.gc_cookie = sc;
        sc->sc_gc.gc_config_pin = pcagpio_config_pin;
        sc->sc_gc.gc_get_pin = pcagpio_get_pin;
        sc->sc_gc.gc_set_pin = pcagpio_set_pin;
        gpio_controller_register(&sc->sc_gc);
}

int
pcagpio_init(struct pcagpio_softc *sc, int port)
{
        u_int8_t cmd, data;

        /* Don't invert input. */
        data = 0;
        cmd = sc->sc_regs[port][PCAGPIO_POLARITY];
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                printf(": failed to initialize\n");
                return (-1);
        }

        return (0);
}

void
pcagpio_config_pin(void *arg, uint32_t *cells, int config)
{
        struct pcagpio_softc *sc = arg;
        uint32_t pin = cells[0];
        u_int8_t cmd, data;
        int port, bit;

        if (pin >= 16)
                return;

        port = PCAGPIO_PORT(pin);
        bit = PCAGPIO_BIT(pin);

        cmd = sc->sc_regs[port][PCAGPIO_CONFIG];
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0))
                return;

        if (config & GPIO_CONFIG_OUTPUT)
                data &= ~bit;
        else
                data |= bit;

        cmd = sc->sc_regs[port][PCAGPIO_CONFIG];
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0))
                return;
}

int
pcagpio_get_pin(void *arg, uint32_t *cells)
{
        struct pcagpio_softc *sc = arg;
        uint32_t pin = cells[0];
        uint32_t flags = cells[1];
        u_int8_t cmd, data;
        int port, bit, value;

        if (pin >= 16)
                return 0;

        port = PCAGPIO_PORT(pin);
        bit = PCAGPIO_BIT(pin);

        cmd = sc->sc_regs[port][PCAGPIO_IN];
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0))
                return 0;

        value = !!(data & bit);
        if (flags & GPIO_ACTIVE_LOW)
                value = !value;

        return value;
}

void
pcagpio_set_pin(void *arg, uint32_t *cells, int value)
{
        struct pcagpio_softc *sc = arg;
        uint32_t pin = cells[0];
        uint32_t flags = cells[1];
        u_int8_t cmd, data;
        int port, bit;

        if (pin >= 16)
                return;

        port = PCAGPIO_PORT(pin);
        bit = PCAGPIO_BIT(pin);

        cmd = sc->sc_regs[port][PCAGPIO_OUT];
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0))
                return;

        if (flags & GPIO_ACTIVE_LOW)
                value = !value;

        data &= ~bit;
        if (value)
                data |= bit;

        cmd = sc->sc_regs[port][PCAGPIO_OUT];
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0))
                return;
}