/*
 * Mac80211 SDIO driver for ST-Ericsson CW1200 device
 *
 * Copyright (c) 2010, ST-Ericsson
 * Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/mmc/host.h>
#include <linux/mmc/sdio_func.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio.h>
#include <net/mac80211.h>

#include "cw1200.h"
#include "hwbus.h"
#include <linux/platform_data/net-cw1200.h>
#include "hwio.h"

MODULE_AUTHOR("Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>");
MODULE_DESCRIPTION("mac80211 ST-Ericsson CW1200 SDIO driver");
MODULE_LICENSE("GPL");

#define SDIO_BLOCK_SIZE (512)

/* Default platform data for Sagrad modules */
static struct cw1200_platform_data_sdio sagrad_109x_evk_platform_data = {
        .ref_clk = 38400,
        .have_5ghz = false,
        .sdd_file = "sdd_sagrad_1091_1098.bin",
};

/* Allow platform data to be overridden */
static struct cw1200_platform_data_sdio *global_plat_data = &sagrad_109x_evk_platform_data;

void __init cw1200_sdio_set_platform_data(struct cw1200_platform_data_sdio *pdata)
{
        global_plat_data = pdata;
}

struct hwbus_priv {
        struct sdio_func        *func;
        struct cw1200_common    *core;
        const struct cw1200_platform_data_sdio *pdata;
};

#ifndef SDIO_VENDOR_ID_STE
#define SDIO_VENDOR_ID_STE              0x0020
#endif

#ifndef SDIO_DEVICE_ID_STE_CW1200
#define SDIO_DEVICE_ID_STE_CW1200       0x2280
#endif

static const struct sdio_device_id cw1200_sdio_ids[] = {
        { SDIO_DEVICE(SDIO_VENDOR_ID_STE, SDIO_DEVICE_ID_STE_CW1200) },
        { /* end: all zeroes */                 },
};

/* hwbus_ops implemetation */

static int cw1200_sdio_memcpy_fromio(struct hwbus_priv *self,
                                     unsigned int addr,
                                     void *dst, int count)
{
        return sdio_memcpy_fromio(self->func, dst, addr, count);
}

static int cw1200_sdio_memcpy_toio(struct hwbus_priv *self,
                                   unsigned int addr,
                                   const void *src, int count)
{
        return sdio_memcpy_toio(self->func, addr, (void *)src, count);
}

static void cw1200_sdio_lock(struct hwbus_priv *self)
{
        sdio_claim_host(self->func);
}

static void cw1200_sdio_unlock(struct hwbus_priv *self)
{
        sdio_release_host(self->func);
}

static void cw1200_sdio_irq_handler(struct sdio_func *func)
{
        struct hwbus_priv *self = sdio_get_drvdata(func);

        /* note:  sdio_host already claimed here. */
        if (self->core)
                cw1200_irq_handler(self->core);
}

static irqreturn_t cw1200_gpio_hardirq(int irq, void *dev_id)
{
        return IRQ_WAKE_THREAD;
}

static irqreturn_t cw1200_gpio_irq(int irq, void *dev_id)
{
        struct hwbus_priv *self = dev_id;

        if (self->core) {
                cw1200_sdio_lock(self);
                cw1200_irq_handler(self->core);
                cw1200_sdio_unlock(self);
                return IRQ_HANDLED;
        } else {
                return IRQ_NONE;
        }
}

static int cw1200_request_irq(struct hwbus_priv *self)
{
        int ret;
        u8 cccr;

        cccr = sdio_f0_readb(self->func, SDIO_CCCR_IENx, &ret);
        if (WARN_ON(ret))
                goto err;

        /* Master interrupt enable ... */
        cccr |= BIT(0);

        /* ... for our function */
        cccr |= BIT(self->func->num);

        sdio_f0_writeb(self->func, cccr, SDIO_CCCR_IENx, &ret);
        if (WARN_ON(ret))
                goto err;

        ret = enable_irq_wake(self->pdata->irq);
        if (WARN_ON(ret))
                goto err;

        /* Request the IRQ */
        ret =  request_threaded_irq(self->pdata->irq, cw1200_gpio_hardirq,
                                    cw1200_gpio_irq,
                                    IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
                                    "cw1200_wlan_irq", self);
        if (WARN_ON(ret))
                goto err;

        return 0;

err:
        return ret;
}

static int cw1200_sdio_irq_subscribe(struct hwbus_priv *self)
{
        int ret = 0;

        pr_debug("SW IRQ subscribe\n");
        sdio_claim_host(self->func);
        if (self->pdata->irq)
                ret = cw1200_request_irq(self);
        else
                ret = sdio_claim_irq(self->func, cw1200_sdio_irq_handler);

        sdio_release_host(self->func);
        return ret;
}

static int cw1200_sdio_irq_unsubscribe(struct hwbus_priv *self)
{
        int ret = 0;

        pr_debug("SW IRQ unsubscribe\n");

        if (self->pdata->irq) {
                disable_irq_wake(self->pdata->irq);
                free_irq(self->pdata->irq, self);
        } else {
                sdio_claim_host(self->func);
                ret = sdio_release_irq(self->func);
                sdio_release_host(self->func);
        }
        return ret;
}

static int cw1200_sdio_off(const struct cw1200_platform_data_sdio *pdata)
{
        if (pdata->reset) {
                gpio_set_value(pdata->reset, 0);
                msleep(30); /* Min is 2 * CLK32K cycles */
                gpio_free(pdata->reset);
        }

        if (pdata->power_ctrl)
                pdata->power_ctrl(pdata, false);
        if (pdata->clk_ctrl)
                pdata->clk_ctrl(pdata, false);

        return 0;
}

static int cw1200_sdio_on(const struct cw1200_platform_data_sdio *pdata)
{
        /* Ensure I/Os are pulled low */
        if (pdata->reset) {
                gpio_request(pdata->reset, "cw1200_wlan_reset");
                gpio_direction_output(pdata->reset, 0);
        }
        if (pdata->powerup) {
                gpio_request(pdata->powerup, "cw1200_wlan_powerup");
                gpio_direction_output(pdata->powerup, 0);
        }
        if (pdata->reset || pdata->powerup)
                msleep(10); /* Settle time? */

        /* Enable 3v3 and 1v8 to hardware */
        if (pdata->power_ctrl) {
                if (pdata->power_ctrl(pdata, true)) {
                        pr_err("power_ctrl() failed!\n");
                        return -1;
                }
        }

        /* Enable CLK32K */
        if (pdata->clk_ctrl) {
                if (pdata->clk_ctrl(pdata, true)) {
                        pr_err("clk_ctrl() failed!\n");
                        return -1;
                }
                msleep(10); /* Delay until clock is stable for 2 cycles */
        }

        /* Enable POWERUP signal */
        if (pdata->powerup) {
                gpio_set_value(pdata->powerup, 1);
                msleep(250); /* or more..? */
        }
        /* Enable RSTn signal */
        if (pdata->reset) {
                gpio_set_value(pdata->reset, 1);
                msleep(50); /* Or more..? */
        }
        return 0;
}

static size_t cw1200_sdio_align_size(struct hwbus_priv *self, size_t size)
{
        if (self->pdata->no_nptb)
                size = round_up(size, SDIO_BLOCK_SIZE);
        else
                size = sdio_align_size(self->func, size);

        return size;
}

static int cw1200_sdio_pm(struct hwbus_priv *self, bool suspend)
{
        int ret = 0;

        if (self->pdata->irq)
                ret = irq_set_irq_wake(self->pdata->irq, suspend);
        return ret;
}

static struct hwbus_ops cw1200_sdio_hwbus_ops = {
        .hwbus_memcpy_fromio    = cw1200_sdio_memcpy_fromio,
        .hwbus_memcpy_toio      = cw1200_sdio_memcpy_toio,
        .lock                   = cw1200_sdio_lock,
        .unlock                 = cw1200_sdio_unlock,
        .align_size             = cw1200_sdio_align_size,
        .power_mgmt             = cw1200_sdio_pm,
};

/* Probe Function to be called by SDIO stack when device is discovered */
static int cw1200_sdio_probe(struct sdio_func *func,
                             const struct sdio_device_id *id)
{
        struct hwbus_priv *self;
        int status;

        pr_info("cw1200_wlan_sdio: Probe called\n");

        /* We are only able to handle the wlan function */
        if (func->num != 0x01)
                return -ENODEV;

        self = kzalloc(sizeof(*self), GFP_KERNEL);
        if (!self) {
                pr_err("Can't allocate SDIO hwbus_priv.\n");
                return -ENOMEM;
        }

        func->card->quirks |= MMC_QUIRK_LENIENT_FN0;

        self->pdata = global_plat_data; /* FIXME */
        self->func = func;
        sdio_set_drvdata(func, self);
        sdio_claim_host(func);
        sdio_enable_func(func);
        sdio_release_host(func);

        status = cw1200_sdio_irq_subscribe(self);

        status = cw1200_core_probe(&cw1200_sdio_hwbus_ops,
                                   self, &func->dev, &self->core,
                                   self->pdata->ref_clk,
                                   self->pdata->macaddr,
                                   self->pdata->sdd_file,
                                   self->pdata->have_5ghz);
        if (status) {
                cw1200_sdio_irq_unsubscribe(self);
                sdio_claim_host(func);
                sdio_disable_func(func);
                sdio_release_host(func);
                sdio_set_drvdata(func, NULL);
                kfree(self);
        }

        return status;
}

/* Disconnect Function to be called by SDIO stack when
 * device is disconnected
 */
static void cw1200_sdio_disconnect(struct sdio_func *func)
{
        struct hwbus_priv *self = sdio_get_drvdata(func);

        if (self) {
                cw1200_sdio_irq_unsubscribe(self);
                if (self->core) {
                        cw1200_core_release(self->core);
                        self->core = NULL;
                }
                sdio_claim_host(func);
                sdio_disable_func(func);
                sdio_release_host(func);
                sdio_set_drvdata(func, NULL);
                kfree(self);
        }
}

#ifdef CONFIG_PM
static int cw1200_sdio_suspend(struct device *dev)
{
        int ret;
        struct sdio_func *func = dev_to_sdio_func(dev);
        struct hwbus_priv *self = sdio_get_drvdata(func);

        if (!cw1200_can_suspend(self->core))
                return -EAGAIN;

        /* Notify SDIO that CW1200 will remain powered during suspend */
        ret = sdio_set_host_pm_flags(func, MMC_PM_KEEP_POWER);
        if (ret)
                pr_err("Error setting SDIO pm flags: %i\n", ret);

        return ret;
}

static int cw1200_sdio_resume(struct device *dev)
{
        return 0;
}

static const struct dev_pm_ops cw1200_pm_ops = {
        .suspend = cw1200_sdio_suspend,
        .resume = cw1200_sdio_resume,
};
#endif

static struct sdio_driver sdio_driver = {
        .name           = "cw1200_wlan_sdio",
        .id_table       = cw1200_sdio_ids,
        .probe          = cw1200_sdio_probe,
        .remove         = cw1200_sdio_disconnect,
#ifdef CONFIG_PM
        .drv = {
                .pm = &cw1200_pm_ops,
        }
#endif
};

/* Init Module function -> Called by insmod */
static int __init cw1200_sdio_init(void)
{
        const struct cw1200_platform_data_sdio *pdata;
        int ret;

        /* FIXME -- this won't support multiple devices */
        pdata = global_plat_data;

        if (cw1200_sdio_on(pdata)) {
                ret = -1;
                goto err;
        }

        ret = sdio_register_driver(&sdio_driver);
        if (ret)
                goto err;

        return 0;

err:
        cw1200_sdio_off(pdata);
        return ret;
}

/* Called at Driver Unloading */
static void __exit cw1200_sdio_exit(void)
{
        const struct cw1200_platform_data_sdio *pdata;

        /* FIXME -- this won't support multiple devices */
        pdata = global_plat_data;
        sdio_unregister_driver(&sdio_driver);
        cw1200_sdio_off(pdata);
}


module_init(cw1200_sdio_init);
module_exit(cw1200_sdio_exit);