/*
 * linux/drivers/mmc/core/sdio_cis.c
 *
 * Author:      Nicolas Pitre
 * Created:     June 11, 2007
 * Copyright:   MontaVista Software Inc.
 *
 * Copyright 2007 Pierre Ossman
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 */

#include <linux/kernel.h>

#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/sdio_func.h>

#include "sdio_cis.h"
#include "sdio_ops.h"

static int cistpl_vers_1(struct mmc_card *card, struct sdio_func *func,
                         const unsigned char *buf, unsigned size)
{
        unsigned i, nr_strings;
        char **buffer, *string;

        /* Find all null-terminated (including zero length) strings in
           the TPLLV1_INFO field. Trailing garbage is ignored. */
        buf += 2;
        size -= 2;

        nr_strings = 0;
        for (i = 0; i < size; i++) {
                if (buf[i] == 0xff)
                        break;
                if (buf[i] == 0)
                        nr_strings++;
        }
        if (nr_strings == 0)
                return 0;

        size = i;

        buffer = kzalloc(sizeof(char*) * nr_strings + size, GFP_KERNEL);
        if (!buffer)
                return -ENOMEM;

        string = (char*)(buffer + nr_strings);

        for (i = 0; i < nr_strings; i++) {
                buffer[i] = string;
                strcpy(string, buf);
                string += strlen(string) + 1;
                buf += strlen(buf) + 1;
        }

        if (func) {
                func->num_info = nr_strings;
                func->info = (const char**)buffer;
        } else {
                card->num_info = nr_strings;
                card->info = (const char**)buffer;
        }

        return 0;
}

static int cistpl_manfid(struct mmc_card *card, struct sdio_func *func,
                         const unsigned char *buf, unsigned size)
{
        unsigned int vendor, device;

        /* TPLMID_MANF */
        vendor = buf[0] | (buf[1] << 8);

        /* TPLMID_CARD */
        device = buf[2] | (buf[3] << 8);

        if (func) {
                func->vendor = vendor;
                func->device = device;
        } else {
                card->cis.vendor = vendor;
                card->cis.device = device;
        }

        return 0;
}

static const unsigned char speed_val[16] =
        { 0, 10, 12, 13, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80 };
static const unsigned int speed_unit[8] =
        { 10000, 100000, 1000000, 10000000, 0, 0, 0, 0 };

/* FUNCE tuples with these types get passed to SDIO drivers */
static const unsigned char funce_type_whitelist[] = {
        4 /* CISTPL_FUNCE_LAN_NODE_ID used in Broadcom cards */
};

static int cistpl_funce_whitelisted(unsigned char type)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(funce_type_whitelist); i++) {
                if (funce_type_whitelist[i] == type)
                        return 1;
        }
        return 0;
}

static int cistpl_funce_common(struct mmc_card *card,
                               const unsigned char *buf, unsigned size)
{
        if (size < 0x04 || buf[0] != 0)
                return -EINVAL;

        /* TPLFE_FN0_BLK_SIZE */
        card->cis.blksize = buf[1] | (buf[2] << 8);

        /* TPLFE_MAX_TRAN_SPEED */
        card->cis.max_dtr = speed_val[(buf[3] >> 3) & 15] *
                            speed_unit[buf[3] & 7];

        return 0;
}

static int cistpl_funce_func(struct sdio_func *func,
                             const unsigned char *buf, unsigned size)
{
        unsigned vsn;
        unsigned min_size;

        /* let SDIO drivers take care of whitelisted FUNCE tuples */
        if (cistpl_funce_whitelisted(buf[0]))
                return -EILSEQ;

        vsn = func->card->cccr.sdio_vsn;
        min_size = (vsn == SDIO_SDIO_REV_1_00) ? 28 : 42;

        if (size < min_size || buf[0] != 1)
                return -EINVAL;

        /* TPLFE_MAX_BLK_SIZE */
        func->max_blksize = buf[12] | (buf[13] << 8);

        /* TPLFE_ENABLE_TIMEOUT_VAL, present in ver 1.1 and above */
        if (vsn > SDIO_SDIO_REV_1_00)
                func->enable_timeout = (buf[28] | (buf[29] << 8)) * 10;
        else
                func->enable_timeout = jiffies_to_msecs(HZ);

        return 0;
}

static int cistpl_funce(struct mmc_card *card, struct sdio_func *func,
                        const unsigned char *buf, unsigned size)
{
        int ret;

        /*
         * There should be two versions of the CISTPL_FUNCE tuple,
         * one for the common CIS (function 0) and a version used by
         * the individual function's CIS (1-7). Yet, the later has a
         * different length depending on the SDIO spec version.
         */
        if (func)
                ret = cistpl_funce_func(func, buf, size);
        else
                ret = cistpl_funce_common(card, buf, size);

        if (ret && ret != -EILSEQ) {
                printk(KERN_ERR "%s: bad CISTPL_FUNCE size %u "
                       "type %u\n", mmc_hostname(card->host), size, buf[0]);
        }

        return ret;
}

typedef int (tpl_parse_t)(struct mmc_card *, struct sdio_func *,
                           const unsigned char *, unsigned);

struct cis_tpl {
        unsigned char code;
        unsigned char min_size;
        tpl_parse_t *parse;
};

static const struct cis_tpl cis_tpl_list[] = {
        {       0x15,   3,      cistpl_vers_1           },
        {       0x20,   4,      cistpl_manfid           },
        {       0x21,   2,      /* cistpl_funcid */     },
        {       0x22,   0,      cistpl_funce            },
};

static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)
{
        int ret;
        struct sdio_func_tuple *this, **prev;
        unsigned i, ptr = 0;

        /*
         * Note that this works for the common CIS (function number 0) as
         * well as a function's CIS * since SDIO_CCCR_CIS and SDIO_FBR_CIS
         * have the same offset.
         */
        for (i = 0; i < 3; i++) {
                unsigned char x, fn;

                if (func)
                        fn = func->num;
                else
                        fn = 0;

                ret = mmc_io_rw_direct(card, 0, 0,
                        SDIO_FBR_BASE(fn) + SDIO_FBR_CIS + i, 0, &x);
                if (ret)
                        return ret;
                ptr |= x << (i * 8);
        }

        if (func)
                prev = &func->tuples;
        else
                prev = &card->tuples;

        BUG_ON(*prev);

        do {
                unsigned char tpl_code, tpl_link;

                ret = mmc_io_rw_direct(card, 0, 0, ptr++, 0, &tpl_code);
                if (ret)
                        break;

                /* 0xff means we're done */
                if (tpl_code == 0xff)
                        break;

                /* null entries have no link field or data */
                if (tpl_code == 0x00)
                        continue;

                ret = mmc_io_rw_direct(card, 0, 0, ptr++, 0, &tpl_link);
                if (ret)
                        break;

                /* a size of 0xff also means we're done */
                if (tpl_link == 0xff)
                        break;

                this = kmalloc(sizeof(*this) + tpl_link, GFP_KERNEL);
                if (!this)
                        return -ENOMEM;

                for (i = 0; i < tpl_link; i++) {
                        ret = mmc_io_rw_direct(card, 0, 0,
                                               ptr + i, 0, &this->data[i]);
                        if (ret)
                                break;
                }
                if (ret) {
                        kfree(this);
                        break;
                }

                for (i = 0; i < ARRAY_SIZE(cis_tpl_list); i++)
                        if (cis_tpl_list[i].code == tpl_code)
                                break;
                if (i < ARRAY_SIZE(cis_tpl_list)) {
                        const struct cis_tpl *tpl = cis_tpl_list + i;
                        if (tpl_link < tpl->min_size) {
                                printk(KERN_ERR
                                       "%s: bad CIS tuple 0x%02x"
                                       " (length = %u, expected >= %u)\n",
                                       mmc_hostname(card->host),
                                       tpl_code, tpl_link, tpl->min_size);
                                ret = -EINVAL;
                        } else if (tpl->parse) {
                                ret = tpl->parse(card, func,
                                                 this->data, tpl_link);
                        }
                        /*
                         * We don't need the tuple anymore if it was
                         * successfully parsed by the SDIO core or if it is
                         * not going to be parsed by SDIO drivers.
                         */
                        if (!ret || ret != -EILSEQ)
                                kfree(this);
                } else {
                        /* unknown tuple */
                        ret = -EILSEQ;
                }

                if (ret == -EILSEQ) {
                        /* this tuple is unknown to the core or whitelisted */
                        this->next = NULL;
                        this->code = tpl_code;
                        this->size = tpl_link;
                        *prev = this;
                        prev = &this->next;
                        printk(KERN_DEBUG
                               "%s: queuing CIS tuple 0x%02x length %u\n",
                               mmc_hostname(card->host), tpl_code, tpl_link);
                        /* keep on analyzing tuples */
                        ret = 0;
                }

                ptr += tpl_link;
        } while (!ret);

        /*
         * Link in all unknown tuples found in the common CIS so that
         * drivers don't have to go digging in two places.
         */
        if (func)
                *prev = card->tuples;

        return ret;
}

int sdio_read_common_cis(struct mmc_card *card)
{
        return sdio_read_cis(card, NULL);
}

void sdio_free_common_cis(struct mmc_card *card)
{
        struct sdio_func_tuple *tuple, *victim;

        tuple = card->tuples;

        while (tuple) {
                victim = tuple;
                tuple = tuple->next;
                kfree(victim);
        }

        card->tuples = NULL;
}

int sdio_read_func_cis(struct sdio_func *func)
{
        int ret;

        ret = sdio_read_cis(func->card, func);
        if (ret)
                return ret;

        /*
         * Since we've linked to tuples in the card structure,
         * we must make sure we have a reference to it.
         */
        get_device(&func->card->dev);

        /*
         * Vendor/device id is optional for function CIS, so
         * copy it from the card structure as needed.
         */
        if (func->vendor == 0) {
                func->vendor = func->card->cis.vendor;
                func->device = func->card->cis.device;
        }

        return 0;
}

void sdio_free_func_cis(struct sdio_func *func)
{
        struct sdio_func_tuple *tuple, *victim;

        tuple = func->tuples;

        while (tuple && tuple != func->card->tuples) {
                victim = tuple;
                tuple = tuple->next;
                kfree(victim);
        }

        func->tuples = NULL;

        /*
         * We have now removed the link to the tuples in the
         * card structure, so remove the reference.
         */
        put_device(&func->card->dev);
}