// SPDX-License-Identifier: GPL-2.0
/*
 * linux/arch/arm/mach-sa1100/neponset.c
 */
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/gpio-reg.h>
#include <linux/gpio/machine.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/serial_core.h>
#include <linux/slab.h>
#include <linux/smc91x.h>

#include <asm/mach-types.h>
#include <asm/mach/map.h>
#include <asm/hardware/sa1111.h>
#include <linux/sizes.h>

#include <mach/hardware.h>
#include <mach/assabet.h>
#include <mach/neponset.h>
#include <mach/irqs.h>

#define NEP_IRQ_SMC91X  0
#define NEP_IRQ_USAR    1
#define NEP_IRQ_SA1111  2
#define NEP_IRQ_NR      3

#define WHOAMI          0x00
#define LEDS            0x10
#define SWPK            0x20
#define IRR             0x24
#define KP_Y_IN         0x80
#define KP_X_OUT        0x90
#define NCR_0           0xa0
#define MDM_CTL_0       0xb0
#define MDM_CTL_1       0xb4
#define AUD_CTL         0xc0

#define IRR_ETHERNET    (1 << 0)
#define IRR_USAR        (1 << 1)
#define IRR_SA1111      (1 << 2)

#define NCR_NGPIO       7
#define MDM_CTL0_NGPIO  4
#define MDM_CTL1_NGPIO  6
#define AUD_NGPIO       2

extern void sa1110_mb_disable(void);

#define to_neponset_gpio_chip(x) container_of(x, struct neponset_gpio_chip, gc)

static const char *neponset_ncr_names[] = {
        "gp01_off", "tp_power", "ms_power", "enet_osc",
        "spi_kb_wk_up", "a0vpp", "a1vpp"
};

static const char *neponset_mdmctl0_names[] = {
        "rts3", "dtr3", "rts1", "dtr1",
};

static const char *neponset_mdmctl1_names[] = {
        "cts3", "dsr3", "dcd3", "cts1", "dsr1", "dcd1"
};

static const char *neponset_aud_names[] = {
        "sel_1341", "mute_1341",
};

struct neponset_drvdata {
        void __iomem *base;
        struct platform_device *sa1111;
        struct platform_device *smc91x;
        unsigned irq_base;
        struct gpio_chip *gpio[4];
};

static struct gpiod_lookup_table neponset_uart1_gpio_table = {
        .dev_id = "sa11x0-uart.1",
        .table = {
                GPIO_LOOKUP("neponset-mdm-ctl0", 2, "rts", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl0", 3, "dtr", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl1", 3, "cts", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl1", 4, "dsr", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl1", 5, "dcd", GPIO_ACTIVE_LOW),
                { },
        },
};

static struct gpiod_lookup_table neponset_uart3_gpio_table = {
        .dev_id = "sa11x0-uart.3",
        .table = {
                GPIO_LOOKUP("neponset-mdm-ctl0", 0, "rts", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl0", 1, "dtr", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl1", 0, "cts", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl1", 1, "dsr", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("neponset-mdm-ctl1", 2, "dcd", GPIO_ACTIVE_LOW),
                { },
        },
};

static struct gpiod_lookup_table neponset_pcmcia_table = {
        .dev_id = "1800",
        .table = {
                GPIO_LOOKUP("sa1111", 1, "a0vcc", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("sa1111", 0, "a1vcc", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("neponset-ncr", 5, "a0vpp", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("neponset-ncr", 6, "a1vpp", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("sa1111", 2, "b0vcc", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("sa1111", 3, "b1vcc", GPIO_ACTIVE_HIGH),
                { },
        },
};

static struct neponset_drvdata *nep;

void neponset_ncr_frob(unsigned int mask, unsigned int val)
{
        struct neponset_drvdata *n = nep;
        unsigned long m = mask, v = val;

        if (nep)
                n->gpio[0]->set_multiple(n->gpio[0], &m, &v);
        else
                WARN(1, "nep unset\n");
}
EXPORT_SYMBOL(neponset_ncr_frob);

/*
 * Install handler for Neponset IRQ.  Note that we have to loop here
 * since the ETHERNET and USAR IRQs are level based, and we need to
 * ensure that the IRQ signal is deasserted before returning.  This
 * is rather unfortunate.
 */
static void neponset_irq_handler(struct irq_desc *desc)
{
        struct neponset_drvdata *d = irq_desc_get_handler_data(desc);
        unsigned int irr;

        while (1) {
                /*
                 * Acknowledge the parent IRQ.
                 */
                desc->irq_data.chip->irq_ack(&desc->irq_data);

                /*
                 * Read the interrupt reason register.  Let's have all
                 * active IRQ bits high.  Note: there is a typo in the
                 * Neponset user's guide for the SA1111 IRR level.
                 */
                irr = readb_relaxed(d->base + IRR);
                irr ^= IRR_ETHERNET | IRR_USAR;

                if ((irr & (IRR_ETHERNET | IRR_USAR | IRR_SA1111)) == 0)
                        break;

                /*
                 * Since there is no individual mask, we have to
                 * mask the parent IRQ.  This is safe, since we'll
                 * recheck the register for any pending IRQs.
                 */
                if (irr & (IRR_ETHERNET | IRR_USAR)) {
                        desc->irq_data.chip->irq_mask(&desc->irq_data);

                        /*
                         * Ack the interrupt now to prevent re-entering
                         * this neponset handler.  Again, this is safe
                         * since we'll check the IRR register prior to
                         * leaving.
                         */
                        desc->irq_data.chip->irq_ack(&desc->irq_data);

                        if (irr & IRR_ETHERNET)
                                generic_handle_irq(d->irq_base + NEP_IRQ_SMC91X);

                        if (irr & IRR_USAR)
                                generic_handle_irq(d->irq_base + NEP_IRQ_USAR);

                        desc->irq_data.chip->irq_unmask(&desc->irq_data);
                }

                if (irr & IRR_SA1111)
                        generic_handle_irq(d->irq_base + NEP_IRQ_SA1111);
        }
}

/* Yes, we really do not have any kind of masking or unmasking */
static void nochip_noop(struct irq_data *irq)
{
}

static struct irq_chip nochip = {
        .name = "neponset",
        .irq_ack = nochip_noop,
        .irq_mask = nochip_noop,
        .irq_unmask = nochip_noop,
};

static int neponset_init_gpio(struct gpio_chip **gcp,
        struct device *dev, const char *label, void __iomem *reg,
        unsigned num, bool in, const char *const * names)
{
        struct gpio_chip *gc;

        gc = gpio_reg_init(dev, reg, -1, num, label, in ? 0xffffffff : 0,
                           readl_relaxed(reg), names, NULL, NULL);
        if (IS_ERR(gc))
                return PTR_ERR(gc);

        *gcp = gc;

        return 0;
}

static struct sa1111_platform_data sa1111_info = {
        .disable_devs   = SA1111_DEVID_PS2_MSE,
};

static int neponset_probe(struct platform_device *dev)
{
        struct neponset_drvdata *d;
        struct resource *nep_res, *sa1111_res, *smc91x_res;
        struct resource sa1111_resources[] = {
                DEFINE_RES_MEM(0x40000000, SZ_8K),
                { .flags = IORESOURCE_IRQ },
        };
        struct platform_device_info sa1111_devinfo = {
                .parent = &dev->dev,
                .name = "sa1111",
                .id = 0,
                .res = sa1111_resources,
                .num_res = ARRAY_SIZE(sa1111_resources),
                .data = &sa1111_info,
                .size_data = sizeof(sa1111_info),
                .dma_mask = 0xffffffffUL,
        };
        struct resource smc91x_resources[] = {
                DEFINE_RES_MEM_NAMED(SA1100_CS3_PHYS,
                        0x02000000, "smc91x-regs"),
                DEFINE_RES_MEM_NAMED(SA1100_CS3_PHYS + 0x02000000,
                        0x02000000, "smc91x-attrib"),
                { .flags = IORESOURCE_IRQ },
        };
        struct smc91x_platdata smc91x_platdata = {
                .flags = SMC91X_USE_8BIT | SMC91X_IO_SHIFT_2 | SMC91X_NOWAIT,
        };
        struct platform_device_info smc91x_devinfo = {
                .parent = &dev->dev,
                .name = "smc91x",
                .id = 0,
                .res = smc91x_resources,
                .num_res = ARRAY_SIZE(smc91x_resources),
                .data = &smc91x_platdata,
                .size_data = sizeof(smc91x_platdata),
        };
        int ret, irq;

        if (nep)
                return -EBUSY;

        irq = ret = platform_get_irq(dev, 0);
        if (ret < 0)
                goto err_alloc;

        nep_res = platform_get_resource(dev, IORESOURCE_MEM, 0);
        smc91x_res = platform_get_resource(dev, IORESOURCE_MEM, 1);
        sa1111_res = platform_get_resource(dev, IORESOURCE_MEM, 2);
        if (!nep_res || !smc91x_res || !sa1111_res) {
                ret = -ENXIO;
                goto err_alloc;
        }

        d = kzalloc_obj(*d);
        if (!d) {
                ret = -ENOMEM;
                goto err_alloc;
        }

        d->base = ioremap(nep_res->start, SZ_4K);
        if (!d->base) {
                ret = -ENOMEM;
                goto err_ioremap;
        }

        if (readb_relaxed(d->base + WHOAMI) != 0x11) {
                dev_warn(&dev->dev, "Neponset board detected, but wrong ID: %02x\n",
                         readb_relaxed(d->base + WHOAMI));
                ret = -ENODEV;
                goto err_id;
        }

        ret = irq_alloc_descs(-1, IRQ_BOARD_START, NEP_IRQ_NR, -1);
        if (ret <= 0) {
                dev_err(&dev->dev, "unable to allocate %u irqs: %d\n",
                        NEP_IRQ_NR, ret);
                if (ret == 0)
                        ret = -ENOMEM;
                goto err_irq_alloc;
        }

        d->irq_base = ret;

        irq_set_chip_and_handler(d->irq_base + NEP_IRQ_SMC91X, &nochip,
                handle_simple_irq);
        irq_clear_status_flags(d->irq_base + NEP_IRQ_SMC91X, IRQ_NOREQUEST | IRQ_NOPROBE);
        irq_set_chip_and_handler(d->irq_base + NEP_IRQ_USAR, &nochip,
                handle_simple_irq);
        irq_clear_status_flags(d->irq_base + NEP_IRQ_USAR, IRQ_NOREQUEST | IRQ_NOPROBE);
        irq_set_chip(d->irq_base + NEP_IRQ_SA1111, &nochip);

        irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
        irq_set_chained_handler_and_data(irq, neponset_irq_handler, d);

        /* Disable GPIO 0/1 drivers so the buttons work on the Assabet */
        writeb_relaxed(NCR_GP01_OFF, d->base + NCR_0);

        neponset_init_gpio(&d->gpio[0], &dev->dev, "neponset-ncr",
                           d->base + NCR_0, NCR_NGPIO, false,
                           neponset_ncr_names);
        neponset_init_gpio(&d->gpio[1], &dev->dev, "neponset-mdm-ctl0",
                           d->base + MDM_CTL_0, MDM_CTL0_NGPIO, false,
                           neponset_mdmctl0_names);
        neponset_init_gpio(&d->gpio[2], &dev->dev, "neponset-mdm-ctl1",
                           d->base + MDM_CTL_1, MDM_CTL1_NGPIO, true,
                           neponset_mdmctl1_names);
        neponset_init_gpio(&d->gpio[3], &dev->dev, "neponset-aud-ctl",
                           d->base + AUD_CTL, AUD_NGPIO, false,
                           neponset_aud_names);

        gpiod_add_lookup_table(&neponset_uart1_gpio_table);
        gpiod_add_lookup_table(&neponset_uart3_gpio_table);
        gpiod_add_lookup_table(&neponset_pcmcia_table);

        /*
         * We would set IRQ_GPIO25 to be a wake-up IRQ, but unfortunately
         * something on the Neponset activates this IRQ on sleep (eth?)
         */
#if 0
        enable_irq_wake(irq);
#endif

        dev_info(&dev->dev, "Neponset daughter board, providing IRQ%u-%u\n",
                 d->irq_base, d->irq_base + NEP_IRQ_NR - 1);
        nep = d;

        /* Ensure that the memory bus request/grant signals are setup */
        sa1110_mb_disable();

        sa1111_resources[0].parent = sa1111_res;
        sa1111_resources[1].start = d->irq_base + NEP_IRQ_SA1111;
        sa1111_resources[1].end = d->irq_base + NEP_IRQ_SA1111;
        d->sa1111 = platform_device_register_full(&sa1111_devinfo);

        smc91x_resources[0].parent = smc91x_res;
        smc91x_resources[1].parent = smc91x_res;
        smc91x_resources[2].start = d->irq_base + NEP_IRQ_SMC91X;
        smc91x_resources[2].end = d->irq_base + NEP_IRQ_SMC91X;
        d->smc91x = platform_device_register_full(&smc91x_devinfo);

        platform_set_drvdata(dev, d);

        return 0;

 err_irq_alloc:
 err_id:
        iounmap(d->base);
 err_ioremap:
        kfree(d);
 err_alloc:
        return ret;
}

static void neponset_remove(struct platform_device *dev)
{
        struct neponset_drvdata *d = platform_get_drvdata(dev);
        int irq = platform_get_irq(dev, 0);

        if (!IS_ERR(d->sa1111))
                platform_device_unregister(d->sa1111);
        if (!IS_ERR(d->smc91x))
                platform_device_unregister(d->smc91x);

        gpiod_remove_lookup_table(&neponset_pcmcia_table);
        gpiod_remove_lookup_table(&neponset_uart3_gpio_table);
        gpiod_remove_lookup_table(&neponset_uart1_gpio_table);

        irq_set_chained_handler(irq, NULL);
        irq_free_descs(d->irq_base, NEP_IRQ_NR);
        nep = NULL;
        iounmap(d->base);
        kfree(d);
}

#ifdef CONFIG_PM_SLEEP
static int neponset_resume(struct device *dev)
{
        struct neponset_drvdata *d = dev_get_drvdata(dev);
        int i, ret = 0;

        for (i = 0; i < ARRAY_SIZE(d->gpio); i++) {
                ret = gpio_reg_resume(d->gpio[i]);
                if (ret)
                        break;
        }

        return ret;
}

static const struct dev_pm_ops neponset_pm_ops = {
        .resume_noirq = neponset_resume,
        .restore_noirq = neponset_resume,
};
#define PM_OPS &neponset_pm_ops
#else
#define PM_OPS NULL
#endif

static struct platform_driver neponset_device_driver = {
        .probe          = neponset_probe,
        .remove         = neponset_remove,
        .driver         = {
                .name   = "neponset",
                .pm     = PM_OPS,
        },
};

static int __init neponset_init(void)
{
        return platform_driver_register(&neponset_device_driver);
}

subsys_initcall(neponset_init);