// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * linux/drivers/mmc/core/sdio_cis.c
 *
 * Author:      Nicolas Pitre
 * Created:     June 11, 2007
 * Copyright:   MontaVista Software Inc.
 *
 * Copyright 2007 Pierre Ossman
 */

#include <linux/kernel.h>
#include <linux/slab.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"

#define SDIO_READ_CIS_TIMEOUT_MS  (10 * 1000) /* 10s */

static int cistpl_vers_1(struct mmc_card *card, struct sdio_func *func,
                         const unsigned char *buf, unsigned size)
{
        u8 major_rev, minor_rev;
        unsigned i, nr_strings;
        char **buffer, *string;

        if (size < 2)
                return 0;

        major_rev = buf[0];
        minor_rev = buf[1];

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


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 int cis_tpl_parse(struct mmc_card *card, struct sdio_func *func,
                         const char *tpl_descr,
                         const struct cis_tpl *tpl, int tpl_count,
                         unsigned char code,
                         const unsigned char *buf, unsigned size)
{
        int i, ret;

        /* look for a matching code in the table */
        for (i = 0; i < tpl_count; i++, tpl++) {
                if (tpl->code == code)
                        break;
        }
        if (i < tpl_count) {
                if (size >= tpl->min_size) {
                        if (tpl->parse)
                                ret = tpl->parse(card, func, buf, size);
                        else
                                ret = -EILSEQ;  /* known tuple, not parsed */
                } else {
                        /* invalid tuple */
                        ret = -EINVAL;
                }
                if (ret && ret != -EILSEQ && ret != -ENOENT) {
                        pr_err("%s: bad %s tuple 0x%02x (%u bytes)\n",
                               mmc_hostname(card->host), tpl_descr, code, size);
                }
        } else {
                /* unknown tuple */
                ret = -ENOENT;
        }

        return ret;
}

static int cistpl_funce_common(struct mmc_card *card, struct sdio_func *func,
                               const unsigned char *buf, unsigned size)
{
        /* Only valid for the common CIS (function 0) */
        if (func)
                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 mmc_card *card, struct sdio_func *func,
                             const unsigned char *buf, unsigned size)
{
        unsigned vsn;
        unsigned min_size;

        /* Only valid for the individual function's CIS (1-7) */
        if (!func)
                return -EINVAL;

        /*
         * This tuple has a different length depending on the SDIO spec
         * version.
         */
        vsn = func->card->cccr.sdio_vsn;
        min_size = (vsn == SDIO_SDIO_REV_1_00) ? 28 : 42;

        if (size == 28 && vsn == SDIO_SDIO_REV_1_10) {
                pr_warn("%s: card has broken SDIO 1.1 CIS, forcing SDIO 1.0\n",
                        mmc_hostname(card->host));
                vsn = SDIO_SDIO_REV_1_00;
        } else if (size < min_size) {
                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;
}

/*
 * Known TPLFE_TYPEs table for CISTPL_FUNCE tuples.
 *
 * Note that, unlike PCMCIA, CISTPL_FUNCE tuples are not parsed depending
 * on the TPLFID_FUNCTION value of the previous CISTPL_FUNCID as on SDIO
 * TPLFID_FUNCTION is always hardcoded to 0x0C.
 */
static const struct cis_tpl cis_tpl_funce_list[] = {
        {       0x00,   4,      cistpl_funce_common             },
        {       0x01,   0,      cistpl_funce_func               },
        {       0x04,   1+1+6,  /* CISTPL_FUNCE_LAN_NODE_ID */  },
};

static int cistpl_funce(struct mmc_card *card, struct sdio_func *func,
                        const unsigned char *buf, unsigned size)
{
        if (size < 1)
                return -EINVAL;

        return cis_tpl_parse(card, func, "CISTPL_FUNCE",
                             cis_tpl_funce_list,
                             ARRAY_SIZE(cis_tpl_funce_list),
                             buf[0], buf, size);
}

/* Known TPL_CODEs table for CIS tuples */
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            },
        {       0x91,   2,      /* cistpl_sdio_std */   },
};

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;

        if (*prev)
                return -EINVAL;

        do {
                unsigned char tpl_code, tpl_link;
                unsigned long timeout = jiffies +
                        msecs_to_jiffies(SDIO_READ_CIS_TIMEOUT_MS);

                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;
                }

                /* Try to parse the CIS tuple */
                ret = cis_tpl_parse(card, func, "CIS",
                                    cis_tpl_list, ARRAY_SIZE(cis_tpl_list),
                                    tpl_code, this->data, tpl_link);
                if (ret == -EILSEQ || ret == -ENOENT) {
                        /*
                         * The tuple is unknown or known but not parsed.
                         * Queue the tuple for the function driver.
                         */
                        this->next = NULL;
                        this->code = tpl_code;
                        this->size = tpl_link;
                        *prev = this;
                        prev = &this->next;

                        if (ret == -ENOENT) {

                                if (time_after(jiffies, timeout))
                                        break;

#define FMT(type) "%s: queuing " type " CIS tuple 0x%02x [%*ph] (%u bytes)\n"
                                /*
                                 * Tuples in this range are reserved for
                                 * vendors, so don't warn about them
                                 */
                                if (tpl_code >= 0x80 && tpl_code <= 0x8f)
                                        pr_debug_ratelimited(FMT("vendor"),
                                                mmc_hostname(card->host),
                                                tpl_code, tpl_link, this->data,
                                                tpl_link);
                                else
                                        pr_warn_ratelimited(FMT("unknown"),
                                                mmc_hostname(card->host),
                                                tpl_code, tpl_link, this->data,
                                                tpl_link);
                        }

                        /* keep on analyzing tuples */
                        ret = 0;
                } else {
                        /*
                         * We don't need the tuple anymore if it was
                         * successfully parsed by the SDIO core or if it is
                         * not going to be queued for a driver.
                         */
                        kfree(this);
                }

                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);
}