sdio_cis.c

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/*
 * 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/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"

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 };


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 < 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        },
};

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;
        }

        /* 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) {
                /* warn about unknown tuples */
                pr_warn_ratelimited("%s: queuing unknown"
                       " CIS tuple 0x%02x (%u bytes)\n",
                       mmc_hostname(card->host),
                       tpl_code, 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);
}