// SPDX-License-Identifier: GPL-2.0-only
/*
 * PCMCIA socket code for the MyCable XXS1500 system.
 *
 * Copyright (c) 2009 Manuel Lauss <manuel.lauss@gmail.com>
 *
 */

#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/resource.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

#include <pcmcia/ss.h>
#include <pcmcia/cistpl.h>

#include <asm/irq.h>
#include <asm/mach-au1x00/au1000.h>

#define MEM_MAP_SIZE    0x400000
#define IO_MAP_SIZE     0x1000


/*
 * 3.3V cards only; all interfacing is done via gpios:
 *
 * 0/1:  carddetect (00 = card present, xx = huh)
 * 4:    card irq
 * 204:  reset (high-act)
 * 205:  buffer enable (low-act)
 * 208/209: card voltage key (00,01,10,11)
 * 210:  battwarn
 * 211:  batdead
 * 214:  power (low-act)
 */
#define GPIO_CDA        0
#define GPIO_CDB        1
#define GPIO_CARDIRQ    4
#define GPIO_RESET      204
#define GPIO_OUTEN      205
#define GPIO_VSL        208
#define GPIO_VSH        209
#define GPIO_BATTDEAD   210
#define GPIO_BATTWARN   211
#define GPIO_POWER      214

struct xxs1500_pcmcia_sock {
        struct pcmcia_socket    socket;
        void            *virt_io;

        phys_addr_t     phys_io;
        phys_addr_t     phys_attr;
        phys_addr_t     phys_mem;

        /* previous flags for set_socket() */
        unsigned int old_flags;
};

#define to_xxs_socket(x) container_of(x, struct xxs1500_pcmcia_sock, socket)

static irqreturn_t cdirq(int irq, void *data)
{
        struct xxs1500_pcmcia_sock *sock = data;

        pcmcia_parse_events(&sock->socket, SS_DETECT);

        return IRQ_HANDLED;
}

static int xxs1500_pcmcia_configure(struct pcmcia_socket *skt,
                                    struct socket_state_t *state)
{
        struct xxs1500_pcmcia_sock *sock = to_xxs_socket(skt);
        unsigned int changed;

        /* power control */
        switch (state->Vcc) {
        case 0:
                gpio_set_value(GPIO_POWER, 1);  /* power off */
                break;
        case 33:
                gpio_set_value(GPIO_POWER, 0);  /* power on */
                break;
        case 50:
        default:
                return -EINVAL;
        }

        changed = state->flags ^ sock->old_flags;

        if (changed & SS_RESET) {
                if (state->flags & SS_RESET) {
                        gpio_set_value(GPIO_RESET, 1);  /* assert reset */
                        gpio_set_value(GPIO_OUTEN, 1);  /* buffers off */
                } else {
                        gpio_set_value(GPIO_RESET, 0);  /* deassert reset */
                        gpio_set_value(GPIO_OUTEN, 0);  /* buffers on */
                        msleep(500);
                }
        }

        sock->old_flags = state->flags;

        return 0;
}

static int xxs1500_pcmcia_get_status(struct pcmcia_socket *skt,
                                     unsigned int *value)
{
        unsigned int status;
        int i;

        status = 0;

        /* check carddetects: GPIO[0:1] must both be low */
        if (!gpio_get_value(GPIO_CDA) && !gpio_get_value(GPIO_CDB))
                status |= SS_DETECT;

        /* determine card voltage: GPIO[208:209] binary value */
        i = (!!gpio_get_value(GPIO_VSL)) | ((!!gpio_get_value(GPIO_VSH)) << 1);

        switch (i) {
        case 0:
        case 1:
        case 2:
                status |= SS_3VCARD;    /* 3V card */
                break;
        case 3:                         /* 5V card, unsupported */
        default:
                status |= SS_XVCARD;    /* treated as unsupported in core */
        }

        /* GPIO214: low active power switch */
        status |= gpio_get_value(GPIO_POWER) ? 0 : SS_POWERON;

        /* GPIO204: high-active reset line */
        status |= gpio_get_value(GPIO_RESET) ? SS_RESET : SS_READY;

        /* other stuff */
        status |= gpio_get_value(GPIO_BATTDEAD) ? 0 : SS_BATDEAD;
        status |= gpio_get_value(GPIO_BATTWARN) ? 0 : SS_BATWARN;

        *value = status;

        return 0;
}

static int xxs1500_pcmcia_sock_init(struct pcmcia_socket *skt)
{
        gpio_direction_input(GPIO_CDA);
        gpio_direction_input(GPIO_CDB);
        gpio_direction_input(GPIO_VSL);
        gpio_direction_input(GPIO_VSH);
        gpio_direction_input(GPIO_BATTDEAD);
        gpio_direction_input(GPIO_BATTWARN);
        gpio_direction_output(GPIO_RESET, 1);   /* assert reset */
        gpio_direction_output(GPIO_OUTEN, 1);   /* disable buffers */
        gpio_direction_output(GPIO_POWER, 1);   /* power off */

        return 0;
}

static int xxs1500_pcmcia_sock_suspend(struct pcmcia_socket *skt)
{
        return 0;
}

static int au1x00_pcmcia_set_io_map(struct pcmcia_socket *skt,
                                    struct pccard_io_map *map)
{
        struct xxs1500_pcmcia_sock *sock = to_xxs_socket(skt);

        map->start = (u32)sock->virt_io;
        map->stop = map->start + IO_MAP_SIZE;

        return 0;
}

static int au1x00_pcmcia_set_mem_map(struct pcmcia_socket *skt,
                                     struct pccard_mem_map *map)
{
        struct xxs1500_pcmcia_sock *sock = to_xxs_socket(skt);

        if (map->flags & MAP_ATTRIB)
                map->static_start = sock->phys_attr + map->card_start;
        else
                map->static_start = sock->phys_mem + map->card_start;

        return 0;
}

static struct pccard_operations xxs1500_pcmcia_operations = {
        .init                   = xxs1500_pcmcia_sock_init,
        .suspend                = xxs1500_pcmcia_sock_suspend,
        .get_status             = xxs1500_pcmcia_get_status,
        .set_socket             = xxs1500_pcmcia_configure,
        .set_io_map             = au1x00_pcmcia_set_io_map,
        .set_mem_map            = au1x00_pcmcia_set_mem_map,
};

static int xxs1500_pcmcia_probe(struct platform_device *pdev)
{
        struct xxs1500_pcmcia_sock *sock;
        struct resource *r;
        int ret, irq;

        sock = kzalloc_obj(struct xxs1500_pcmcia_sock);
        if (!sock)
                return -ENOMEM;

        ret = -ENODEV;

        /* 36bit PCMCIA Attribute area address */
        r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-attr");
        if (!r) {
                dev_err(&pdev->dev, "missing 'pcmcia-attr' resource!\n");
                goto out0;
        }
        sock->phys_attr = r->start;

        /* 36bit PCMCIA Memory area address */
        r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-mem");
        if (!r) {
                dev_err(&pdev->dev, "missing 'pcmcia-mem' resource!\n");
                goto out0;
        }
        sock->phys_mem = r->start;

        /* 36bit PCMCIA IO area address */
        r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-io");
        if (!r) {
                dev_err(&pdev->dev, "missing 'pcmcia-io' resource!\n");
                goto out0;
        }
        sock->phys_io = r->start;


        /*
         * PCMCIA client drivers use the inb/outb macros to access
         * the IO registers.  Since mips_io_port_base is added
         * to the access address of the mips implementation of
         * inb/outb, we need to subtract it here because we want
         * to access the I/O or MEM address directly, without
         * going through this "mips_io_port_base" mechanism.
         */
        sock->virt_io = (void *)(ioremap(sock->phys_io, IO_MAP_SIZE) -
                                 mips_io_port_base);

        if (!sock->virt_io) {
                dev_err(&pdev->dev, "cannot remap IO area\n");
                ret = -ENOMEM;
                goto out0;
        }

        sock->socket.ops        = &xxs1500_pcmcia_operations;
        sock->socket.owner      = THIS_MODULE;
        sock->socket.pci_irq    = gpio_to_irq(GPIO_CARDIRQ);
        sock->socket.features   = SS_CAP_STATIC_MAP | SS_CAP_PCCARD;
        sock->socket.map_size   = MEM_MAP_SIZE;
        sock->socket.io_offset  = (unsigned long)sock->virt_io;
        sock->socket.dev.parent = &pdev->dev;
        sock->socket.resource_ops = &pccard_static_ops;

        platform_set_drvdata(pdev, sock);

        /* setup carddetect irq: use one of the 2 GPIOs as an
         * edge detector.
         */
        irq = gpio_to_irq(GPIO_CDA);
        irq_set_irq_type(irq, IRQ_TYPE_EDGE_BOTH);
        ret = request_irq(irq, cdirq, 0, "pcmcia_carddetect", sock);
        if (ret) {
                dev_err(&pdev->dev, "cannot setup cd irq\n");
                goto out1;
        }

        ret = pcmcia_register_socket(&sock->socket);
        if (ret) {
                dev_err(&pdev->dev, "failed to register\n");
                goto out2;
        }

        printk(KERN_INFO "MyCable XXS1500 PCMCIA socket services\n");

        return 0;

out2:
        free_irq(gpio_to_irq(GPIO_CDA), sock);
out1:
        iounmap((void *)(sock->virt_io + (u32)mips_io_port_base));
out0:
        kfree(sock);
        return ret;
}

static void xxs1500_pcmcia_remove(struct platform_device *pdev)
{
        struct xxs1500_pcmcia_sock *sock = platform_get_drvdata(pdev);

        pcmcia_unregister_socket(&sock->socket);
        free_irq(gpio_to_irq(GPIO_CDA), sock);
        iounmap((void *)(sock->virt_io + (u32)mips_io_port_base));
        kfree(sock);
}

static struct platform_driver xxs1500_pcmcia_socket_driver = {
        .driver = {
                .name   = "xxs1500_pcmcia",
        },
        .probe          = xxs1500_pcmcia_probe,
        .remove         = xxs1500_pcmcia_remove,
};

module_platform_driver(xxs1500_pcmcia_socket_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PCMCIA Socket Services for MyCable XXS1500 systems");
MODULE_AUTHOR("Manuel Lauss");