// SPDX-License-Identifier: GPL-2.0-only
/*
 * PCMCIA high-level CIS access functions
 *
 * The initial developer of the original code is David A. Hinds
 * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
 * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
 *
 * Copyright (C) 1999        David A. Hinds
 * Copyright (C) 2004-2010   Dominik Brodowski
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>

#include <pcmcia/cisreg.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/ss.h>
#include <pcmcia/ds.h>
#include "cs_internal.h"


/**
 * pccard_read_tuple() - internal CIS tuple access
 * @s:          the struct pcmcia_socket where the card is inserted
 * @function:   the device function we loop for
 * @code:       which CIS code shall we look for?
 * @parse:      buffer where the tuple shall be parsed (or NULL, if no parse)
 *
 * pccard_read_tuple() reads out one tuple and attempts to parse it
 */
int pccard_read_tuple(struct pcmcia_socket *s, unsigned int function,
                cisdata_t code, void *parse)
{
        tuple_t tuple;
        cisdata_t *buf;
        int ret;

        buf = kmalloc(256, GFP_KERNEL);
        if (buf == NULL) {
                dev_warn(&s->dev, "no memory to read tuple\n");
                return -ENOMEM;
        }
        tuple.DesiredTuple = code;
        tuple.Attributes = 0;
        if (function == BIND_FN_ALL)
                tuple.Attributes = TUPLE_RETURN_COMMON;
        ret = pccard_get_first_tuple(s, function, &tuple);
        if (ret != 0)
                goto done;
        tuple.TupleData = buf;
        tuple.TupleOffset = 0;
        tuple.TupleDataMax = 255;
        ret = pccard_get_tuple_data(s, &tuple);
        if (ret != 0)
                goto done;
        ret = pcmcia_parse_tuple(&tuple, parse);
done:
        kfree(buf);
        return ret;
}


/**
 * pccard_loop_tuple() - loop over tuples in the CIS
 * @s:          the struct pcmcia_socket where the card is inserted
 * @function:   the device function we loop for
 * @code:       which CIS code shall we look for?
 * @parse:      buffer where the tuple shall be parsed (or NULL, if no parse)
 * @priv_data:  private data to be passed to the loop_tuple function.
 * @loop_tuple: function to call for each CIS entry of type @function. IT
 *              gets passed the raw tuple, the paresed tuple (if @parse is
 *              set) and @priv_data.
 *
 * pccard_loop_tuple() loops over all CIS entries of type @function, and
 * calls the @loop_tuple function for each entry. If the call to @loop_tuple
 * returns 0, the loop exits. Returns 0 on success or errorcode otherwise.
 */
static int pccard_loop_tuple(struct pcmcia_socket *s, unsigned int function,
                             cisdata_t code, cisparse_t *parse, void *priv_data,
                             int (*loop_tuple) (tuple_t *tuple,
                                         cisparse_t *parse,
                                         void *priv_data))
{
        tuple_t tuple;
        cisdata_t *buf;
        int ret;

        buf = kzalloc(256, GFP_KERNEL);
        if (buf == NULL) {
                dev_warn(&s->dev, "no memory to read tuple\n");
                return -ENOMEM;
        }

        tuple.TupleData = buf;
        tuple.TupleDataMax = 255;
        tuple.TupleOffset = 0;
        tuple.DesiredTuple = code;
        tuple.Attributes = 0;

        ret = pccard_get_first_tuple(s, function, &tuple);
        while (!ret) {
                if (pccard_get_tuple_data(s, &tuple))
                        goto next_entry;

                if (parse)
                        if (pcmcia_parse_tuple(&tuple, parse))
                                goto next_entry;

                ret = loop_tuple(&tuple, parse, priv_data);
                if (!ret)
                        break;

next_entry:
                ret = pccard_get_next_tuple(s, function, &tuple);
        }

        kfree(buf);
        return ret;
}


/*
 * pcmcia_io_cfg_data_width() - convert cfgtable to data path width parameter
 */
static int pcmcia_io_cfg_data_width(unsigned int flags)
{
        if (!(flags & CISTPL_IO_8BIT))
                return IO_DATA_PATH_WIDTH_16;
        if (!(flags & CISTPL_IO_16BIT))
                return IO_DATA_PATH_WIDTH_8;
        return IO_DATA_PATH_WIDTH_AUTO;
}


struct pcmcia_cfg_mem {
        struct pcmcia_device *p_dev;
        int (*conf_check) (struct pcmcia_device *p_dev, void *priv_data);
        void *priv_data;
        cisparse_t parse;
        cistpl_cftable_entry_t dflt;
};

/*
 * pcmcia_do_loop_config() - internal helper for pcmcia_loop_config()
 *
 * pcmcia_do_loop_config() is the internal callback for the call from
 * pcmcia_loop_config() to pccard_loop_tuple(). Data is transferred
 * by a struct pcmcia_cfg_mem.
 */
static int pcmcia_do_loop_config(tuple_t *tuple, cisparse_t *parse, void *priv)
{
        struct pcmcia_cfg_mem *cfg_mem = priv;
        struct pcmcia_device *p_dev = cfg_mem->p_dev;
        cistpl_cftable_entry_t *cfg = &parse->cftable_entry;
        cistpl_cftable_entry_t *dflt = &cfg_mem->dflt;
        unsigned int flags = p_dev->config_flags;
        unsigned int vcc = p_dev->socket->socket.Vcc;

        dev_dbg(&p_dev->dev, "testing configuration %x, autoconf %x\n",
                cfg->index, flags);

        /* default values */
        cfg_mem->p_dev->config_index = cfg->index;
        if (cfg->flags & CISTPL_CFTABLE_DEFAULT)
                cfg_mem->dflt = *cfg;

        /* check for matching Vcc? */
        if (flags & CONF_AUTO_CHECK_VCC) {
                if (cfg->vcc.present & (1 << CISTPL_POWER_VNOM)) {
                        if (vcc != cfg->vcc.param[CISTPL_POWER_VNOM] / 10000)
                                return -ENODEV;
                } else if (dflt->vcc.present & (1 << CISTPL_POWER_VNOM)) {
                        if (vcc != dflt->vcc.param[CISTPL_POWER_VNOM] / 10000)
                                return -ENODEV;
                }
        }

        /* set Vpp? */
        if (flags & CONF_AUTO_SET_VPP) {
                if (cfg->vpp1.present & (1 << CISTPL_POWER_VNOM))
                        p_dev->vpp = cfg->vpp1.param[CISTPL_POWER_VNOM] / 10000;
                else if (dflt->vpp1.present & (1 << CISTPL_POWER_VNOM))
                        p_dev->vpp =
                                dflt->vpp1.param[CISTPL_POWER_VNOM] / 10000;
        }

        /* enable audio? */
        if ((flags & CONF_AUTO_AUDIO) && (cfg->flags & CISTPL_CFTABLE_AUDIO))
                p_dev->config_flags |= CONF_ENABLE_SPKR;


        /* IO window settings? */
        if (flags & CONF_AUTO_SET_IO) {
                cistpl_io_t *io = (cfg->io.nwin) ? &cfg->io : &dflt->io;
                int i = 0;

                p_dev->resource[0]->start = p_dev->resource[0]->end = 0;
                p_dev->resource[1]->start = p_dev->resource[1]->end = 0;
                if (io->nwin == 0)
                        return -ENODEV;

                p_dev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
                p_dev->resource[0]->flags |=
                                        pcmcia_io_cfg_data_width(io->flags);
                if (io->nwin > 1) {
                        /* For multifunction cards, by convention, we
                         * configure the network function with window 0,
                         * and serial with window 1 */
                        i = (io->win[1].len > io->win[0].len);
                        p_dev->resource[1]->flags = p_dev->resource[0]->flags;
                        p_dev->resource[1]->start = io->win[1-i].base;
                        p_dev->resource[1]->end = io->win[1-i].len;
                }
                p_dev->resource[0]->start = io->win[i].base;
                p_dev->resource[0]->end = io->win[i].len;
                p_dev->io_lines = io->flags & CISTPL_IO_LINES_MASK;
        }

        /* MEM window settings? */
        if (flags & CONF_AUTO_SET_IOMEM) {
                /* so far, we only set one memory window */
                cistpl_mem_t *mem = (cfg->mem.nwin) ? &cfg->mem : &dflt->mem;

                p_dev->resource[2]->start = p_dev->resource[2]->end = 0;
                if (mem->nwin == 0)
                        return -ENODEV;

                p_dev->resource[2]->start = mem->win[0].host_addr;
                p_dev->resource[2]->end = mem->win[0].len;
                if (p_dev->resource[2]->end < 0x1000)
                        p_dev->resource[2]->end = 0x1000;
                p_dev->card_addr = mem->win[0].card_addr;
        }

        dev_dbg(&p_dev->dev,
                "checking configuration %x: %pr %pr %pr (%d lines)\n",
                p_dev->config_index, p_dev->resource[0], p_dev->resource[1],
                p_dev->resource[2], p_dev->io_lines);

        return cfg_mem->conf_check(p_dev, cfg_mem->priv_data);
}

/**
 * pcmcia_loop_config() - loop over configuration options
 * @p_dev:      the struct pcmcia_device which we need to loop for.
 * @conf_check: function to call for each configuration option.
 *              It gets passed the struct pcmcia_device and private data
 *              being passed to pcmcia_loop_config()
 * @priv_data:  private data to be passed to the conf_check function.
 *
 * pcmcia_loop_config() loops over all configuration options, and calls
 * the driver-specific conf_check() for each one, checking whether
 * it is a valid one. Returns 0 on success or errorcode otherwise.
 */
int pcmcia_loop_config(struct pcmcia_device *p_dev,
                       int      (*conf_check)   (struct pcmcia_device *p_dev,
                                                 void *priv_data),
                       void *priv_data)
{
        struct pcmcia_cfg_mem *cfg_mem;
        int ret;

        cfg_mem = kzalloc(sizeof(struct pcmcia_cfg_mem), GFP_KERNEL);
        if (cfg_mem == NULL)
                return -ENOMEM;

        cfg_mem->p_dev = p_dev;
        cfg_mem->conf_check = conf_check;
        cfg_mem->priv_data = priv_data;

        ret = pccard_loop_tuple(p_dev->socket, p_dev->func,
                                CISTPL_CFTABLE_ENTRY, &cfg_mem->parse,
                                cfg_mem, pcmcia_do_loop_config);

        kfree(cfg_mem);
        return ret;
}
EXPORT_SYMBOL(pcmcia_loop_config);


struct pcmcia_loop_mem {
        struct pcmcia_device *p_dev;
        void *priv_data;
        int (*loop_tuple) (struct pcmcia_device *p_dev,
                           tuple_t *tuple,
                           void *priv_data);
};

/*
 * pcmcia_do_loop_tuple() - internal helper for pcmcia_loop_config()
 *
 * pcmcia_do_loop_tuple() is the internal callback for the call from
 * pcmcia_loop_tuple() to pccard_loop_tuple(). Data is transferred
 * by a struct pcmcia_cfg_mem.
 */
static int pcmcia_do_loop_tuple(tuple_t *tuple, cisparse_t *parse, void *priv)
{
        struct pcmcia_loop_mem *loop = priv;

        return loop->loop_tuple(loop->p_dev, tuple, loop->priv_data);
};

/**
 * pcmcia_loop_tuple() - loop over tuples in the CIS
 * @p_dev:      the struct pcmcia_device which we need to loop for.
 * @code:       which CIS code shall we look for?
 * @priv_data:  private data to be passed to the loop_tuple function.
 * @loop_tuple: function to call for each CIS entry of type @function. IT
 *              gets passed the raw tuple and @priv_data.
 *
 * pcmcia_loop_tuple() loops over all CIS entries of type @function, and
 * calls the @loop_tuple function for each entry. If the call to @loop_tuple
 * returns 0, the loop exits. Returns 0 on success or errorcode otherwise.
 */
int pcmcia_loop_tuple(struct pcmcia_device *p_dev, cisdata_t code,
                      int (*loop_tuple) (struct pcmcia_device *p_dev,
                                         tuple_t *tuple,
                                         void *priv_data),
                      void *priv_data)
{
        struct pcmcia_loop_mem loop = {
                .p_dev = p_dev,
                .loop_tuple = loop_tuple,
                .priv_data = priv_data};

        return pccard_loop_tuple(p_dev->socket, p_dev->func, code, NULL,
                                 &loop, pcmcia_do_loop_tuple);
}
EXPORT_SYMBOL(pcmcia_loop_tuple);


struct pcmcia_loop_get {
        size_t len;
        cisdata_t **buf;
};

/*
 * pcmcia_do_get_tuple() - internal helper for pcmcia_get_tuple()
 *
 * pcmcia_do_get_tuple() is the internal callback for the call from
 * pcmcia_get_tuple() to pcmcia_loop_tuple(). As we're only interested in
 * the first tuple, return 0 unconditionally. Create a memory buffer large
 * enough to hold the content of the tuple, and fill it with the tuple data.
 * The caller is responsible to free the buffer.
 */
static int pcmcia_do_get_tuple(struct pcmcia_device *p_dev, tuple_t *tuple,
                               void *priv)
{
        struct pcmcia_loop_get *get = priv;

        *get->buf = kzalloc(tuple->TupleDataLen, GFP_KERNEL);
        if (*get->buf) {
                get->len = tuple->TupleDataLen;
                memcpy(*get->buf, tuple->TupleData, tuple->TupleDataLen);
        } else
                dev_dbg(&p_dev->dev, "do_get_tuple: out of memory\n");
        return 0;
}

/**
 * pcmcia_get_tuple() - get first tuple from CIS
 * @p_dev:      the struct pcmcia_device which we need to loop for.
 * @code:       which CIS code shall we look for?
 * @buf:        pointer to store the buffer to.
 *
 * pcmcia_get_tuple() gets the content of the first CIS entry of type @code.
 * It returns the buffer length (or zero). The caller is responsible to free
 * the buffer passed in @buf.
 */
size_t pcmcia_get_tuple(struct pcmcia_device *p_dev, cisdata_t code,
                        unsigned char **buf)
{
        struct pcmcia_loop_get get = {
                .len = 0,
                .buf = buf,
        };

        *get.buf = NULL;
        pcmcia_loop_tuple(p_dev, code, pcmcia_do_get_tuple, &get);

        return get.len;
}
EXPORT_SYMBOL(pcmcia_get_tuple);


/*
 * pcmcia_do_get_mac() - internal helper for pcmcia_get_mac_from_cis()
 *
 * pcmcia_do_get_mac() is the internal callback for the call from
 * pcmcia_get_mac_from_cis() to pcmcia_loop_tuple(). We check whether the
 * tuple contains a proper LAN_NODE_ID of length 6, and copy the data
 * to struct net_device->dev_addr[i].
 */
static int pcmcia_do_get_mac(struct pcmcia_device *p_dev, tuple_t *tuple,
                             void *priv)
{
        struct net_device *dev = priv;
        int i;

        if (tuple->TupleData[0] != CISTPL_FUNCE_LAN_NODE_ID)
                return -EINVAL;
        if (tuple->TupleDataLen < ETH_ALEN + 2) {
                dev_warn(&p_dev->dev, "Invalid CIS tuple length for "
                        "LAN_NODE_ID\n");
                return -EINVAL;
        }

        if (tuple->TupleData[1] != ETH_ALEN) {
                dev_warn(&p_dev->dev, "Invalid header for LAN_NODE_ID\n");
                return -EINVAL;
        }
        for (i = 0; i < 6; i++)
                dev->dev_addr[i] = tuple->TupleData[i+2];
        return 0;
}

/**
 * pcmcia_get_mac_from_cis() - read out MAC address from CISTPL_FUNCE
 * @p_dev:      the struct pcmcia_device for which we want the address.
 * @dev:        a properly prepared struct net_device to store the info to.
 *
 * pcmcia_get_mac_from_cis() reads out the hardware MAC address from
 * CISTPL_FUNCE and stores it into struct net_device *dev->dev_addr which
 * must be set up properly by the driver (see examples!).
 */
int pcmcia_get_mac_from_cis(struct pcmcia_device *p_dev, struct net_device *dev)
{
        return pcmcia_loop_tuple(p_dev, CISTPL_FUNCE, pcmcia_do_get_mac, dev);
}
EXPORT_SYMBOL(pcmcia_get_mac_from_cis);