// SPDX-License-Identifier: GPL-2.0
/*
 * card.c - contains functions for managing groups of PnP devices
 *
 * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
 */

#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/ctype.h>
#include <linux/slab.h>
#include <linux/pnp.h>
#include <linux/dma-mapping.h>
#include "base.h"

LIST_HEAD(pnp_cards);
static LIST_HEAD(pnp_card_drivers);

static const struct pnp_card_device_id *match_card(struct pnp_card_driver *drv,
                                                   struct pnp_card *card)
{
        const struct pnp_card_device_id *drv_id = drv->id_table;

        while (*drv_id->id) {
                if (compare_pnp_id(card->id, drv_id->id)) {
                        int i = 0;

                        for (;;) {
                                int found;
                                struct pnp_dev *dev;

                                if (i == PNP_MAX_DEVICES ||
                                    !*drv_id->devs[i].id)
                                        return drv_id;
                                found = 0;
                                card_for_each_dev(card, dev) {
                                        if (compare_pnp_id(dev->id,
                                                   drv_id->devs[i].id)) {
                                                found = 1;
                                                break;
                                        }
                                }
                                if (!found)
                                        break;
                                i++;
                        }
                }
                drv_id++;
        }
        return NULL;
}

static void card_remove(struct pnp_dev *dev)
{
        dev->card_link = NULL;
}

static void card_remove_first(struct pnp_dev *dev)
{
        struct pnp_card_driver *drv = to_pnp_card_driver(dev->driver);

        if (!dev->card || !drv)
                return;
        if (drv->remove)
                drv->remove(dev->card_link);
        drv->link.remove = &card_remove;
        kfree(dev->card_link);
        card_remove(dev);
}

static int card_probe(struct pnp_card *card, struct pnp_card_driver *drv)
{
        const struct pnp_card_device_id *id;
        struct pnp_card_link *clink;
        struct pnp_dev *dev;

        if (!drv->probe)
                return 0;
        id = match_card(drv, card);
        if (!id)
                return 0;

        clink = kzalloc_obj(*clink);
        if (!clink)
                return 0;
        clink->card = card;
        clink->driver = drv;
        clink->pm_state = PMSG_ON;

        if (drv->probe(clink, id) >= 0)
                return 1;

        /* Recovery */
        card_for_each_dev(card, dev) {
                if (dev->card_link == clink)
                        pnp_release_card_device(dev);
        }
        kfree(clink);
        return 0;
}

/**
 * pnp_add_card_id - adds an EISA id to the specified card
 * @id: pointer to a pnp_id structure
 * @card: pointer to the desired card
 */
static struct pnp_id *pnp_add_card_id(struct pnp_card *card, char *id)
{
        struct pnp_id *dev_id, *ptr;

        dev_id = kzalloc_obj(struct pnp_id);
        if (!dev_id)
                return NULL;

        dev_id->id[0] = id[0];
        dev_id->id[1] = id[1];
        dev_id->id[2] = id[2];
        dev_id->id[3] = tolower(id[3]);
        dev_id->id[4] = tolower(id[4]);
        dev_id->id[5] = tolower(id[5]);
        dev_id->id[6] = tolower(id[6]);
        dev_id->id[7] = '\0';

        dev_id->next = NULL;
        ptr = card->id;
        while (ptr && ptr->next)
                ptr = ptr->next;
        if (ptr)
                ptr->next = dev_id;
        else
                card->id = dev_id;

        return dev_id;
}

static void pnp_free_card_ids(struct pnp_card *card)
{
        struct pnp_id *id;
        struct pnp_id *next;

        id = card->id;
        while (id) {
                next = id->next;
                kfree(id);
                id = next;
        }
}

static void pnp_release_card(struct device *dmdev)
{
        struct pnp_card *card = to_pnp_card(dmdev);

        pnp_free_card_ids(card);
        kfree(card);
}

struct pnp_card *pnp_alloc_card(struct pnp_protocol *protocol, int id, char *pnpid)
{
        struct pnp_card *card;
        struct pnp_id *dev_id;

        card = kzalloc_obj(struct pnp_card);
        if (!card)
                return NULL;

        card->protocol = protocol;
        card->number = id;

        card->dev.parent = &card->protocol->dev;
        dev_set_name(&card->dev, "%02x:%02x", card->protocol->number, card->number);

        card->dev.coherent_dma_mask = DMA_BIT_MASK(24);
        card->dev.dma_mask = &card->dev.coherent_dma_mask;

        dev_id = pnp_add_card_id(card, pnpid);
        if (!dev_id) {
                kfree(card);
                return NULL;
        }

        return card;
}

static ssize_t name_show(struct device *dmdev,
                         struct device_attribute *attr, char *buf)
{
        char *str = buf;
        struct pnp_card *card = to_pnp_card(dmdev);

        str += sprintf(str, "%s\n", card->name);
        return (str - buf);
}

static DEVICE_ATTR_RO(name);

static ssize_t card_id_show(struct device *dmdev,
                            struct device_attribute *attr, char *buf)
{
        char *str = buf;
        struct pnp_card *card = to_pnp_card(dmdev);
        struct pnp_id *pos = card->id;

        while (pos) {
                str += sprintf(str, "%s\n", pos->id);
                pos = pos->next;
        }
        return (str - buf);
}

static DEVICE_ATTR_RO(card_id);

static int pnp_interface_attach_card(struct pnp_card *card)
{
        int rc = device_create_file(&card->dev, &dev_attr_name);

        if (rc)
                return rc;

        rc = device_create_file(&card->dev, &dev_attr_card_id);
        if (rc)
                goto err_name;

        return 0;

err_name:
        device_remove_file(&card->dev, &dev_attr_name);
        return rc;
}

/**
 * pnp_add_card - adds a PnP card to the PnP Layer
 * @card: pointer to the card to add
 */
int pnp_add_card(struct pnp_card *card)
{
        int error;
        struct list_head *pos, *temp;

        card->dev.bus = NULL;
        card->dev.release = &pnp_release_card;
        error = device_register(&card->dev);
        if (error) {
                dev_err(&card->dev, "could not register (err=%d)\n", error);
                put_device(&card->dev);
                return error;
        }

        pnp_interface_attach_card(card);
        mutex_lock(&pnp_lock);
        list_add_tail(&card->global_list, &pnp_cards);
        list_add_tail(&card->protocol_list, &card->protocol->cards);
        mutex_unlock(&pnp_lock);

        /* we wait until now to add devices in order to ensure the drivers
         * will be able to use all of the related devices on the card
         * without waiting an unreasonable length of time */
        list_for_each(pos, &card->devices) {
                struct pnp_dev *dev = card_to_pnp_dev(pos);
                __pnp_add_device(dev);
        }

        /* match with card drivers */
        list_for_each_safe(pos, temp, &pnp_card_drivers) {
                struct pnp_card_driver *drv =
                    list_entry(pos, struct pnp_card_driver,
                               global_list);
                card_probe(card, drv);
        }
        return 0;
}

/**
 * pnp_add_card_device - adds a device to the specified card
 * @card: pointer to the card to add to
 * @dev: pointer to the device to add
 */
int pnp_add_card_device(struct pnp_card *card, struct pnp_dev *dev)
{
        dev->dev.parent = &card->dev;
        dev->card_link = NULL;
        dev_set_name(&dev->dev, "%02x:%02x.%02x",
                     dev->protocol->number, card->number, dev->number);
        mutex_lock(&pnp_lock);
        dev->card = card;
        list_add_tail(&dev->card_list, &card->devices);
        mutex_unlock(&pnp_lock);
        return 0;
}

/**
 * pnp_request_card_device - Searches for a PnP device under the specified card
 * @clink: pointer to the card link, cannot be NULL
 * @id: pointer to a PnP ID structure that explains the rules for finding the device
 * @from: Starting place to search from. If NULL it will start from the beginning.
 */
struct pnp_dev *pnp_request_card_device(struct pnp_card_link *clink,
                                        const char *id, struct pnp_dev *from)
{
        struct list_head *pos;
        struct pnp_dev *dev;
        struct pnp_card_driver *drv;
        struct pnp_card *card;

        if (!clink || !id)
                return NULL;

        card = clink->card;
        drv = clink->driver;
        if (!from) {
                pos = card->devices.next;
        } else {
                if (from->card != card)
                        return NULL;
                pos = from->card_list.next;
        }
        while (pos != &card->devices) {
                dev = card_to_pnp_dev(pos);
                if ((!dev->card_link) && compare_pnp_id(dev->id, id))
                        goto found;
                pos = pos->next;
        }

        return NULL;

found:
        dev->card_link = clink;
        dev->dev.driver = &drv->link.driver;
        if (pnp_bus_type.probe(&dev->dev))
                goto err_out;
        if (device_bind_driver(&dev->dev))
                goto err_out;

        return dev;

err_out:
        dev->dev.driver = NULL;
        dev->card_link = NULL;
        return NULL;
}
EXPORT_SYMBOL(pnp_request_card_device);

/**
 * pnp_release_card_device - call this when the driver no longer needs the device
 * @dev: pointer to the PnP device structure
 */
void pnp_release_card_device(struct pnp_dev *dev)
{
        struct pnp_card_driver *drv = dev->card_link->driver;

        drv->link.remove = &card_remove;
        device_release_driver(&dev->dev);
        drv->link.remove = &card_remove_first;
}
EXPORT_SYMBOL(pnp_release_card_device);

/*
 * suspend/resume callbacks
 */
static int card_suspend(struct pnp_dev *dev, pm_message_t state)
{
        struct pnp_card_link *link = dev->card_link;

        if (link->pm_state.event == state.event)
                return 0;
        link->pm_state = state;
        return link->driver->suspend(link, state);
}

static int card_resume(struct pnp_dev *dev)
{
        struct pnp_card_link *link = dev->card_link;

        if (link->pm_state.event == PM_EVENT_ON)
                return 0;
        link->pm_state = PMSG_ON;
        link->driver->resume(link);
        return 0;
}

/**
 * pnp_register_card_driver - registers a PnP card driver with the PnP Layer
 * @drv: pointer to the driver to register
 */
int pnp_register_card_driver(struct pnp_card_driver *drv)
{
        int error;
        struct list_head *pos, *temp;

        drv->link.name = drv->name;
        drv->link.id_table = NULL;      /* this will disable auto matching */
        drv->link.flags = drv->flags;
        drv->link.probe = NULL;
        drv->link.remove = &card_remove_first;
        drv->link.suspend = drv->suspend ? card_suspend : NULL;
        drv->link.resume = drv->resume ? card_resume : NULL;

        error = pnp_register_driver(&drv->link);
        if (error < 0)
                return error;

        mutex_lock(&pnp_lock);
        list_add_tail(&drv->global_list, &pnp_card_drivers);
        mutex_unlock(&pnp_lock);

        list_for_each_safe(pos, temp, &pnp_cards) {
                struct pnp_card *card =
                    list_entry(pos, struct pnp_card, global_list);
                card_probe(card, drv);
        }
        return 0;
}
EXPORT_SYMBOL(pnp_register_card_driver);

/**
 * pnp_unregister_card_driver - unregisters a PnP card driver from the PnP Layer
 * @drv: pointer to the driver to unregister
 */
void pnp_unregister_card_driver(struct pnp_card_driver *drv)
{
        mutex_lock(&pnp_lock);
        list_del(&drv->global_list);
        mutex_unlock(&pnp_lock);
        pnp_unregister_driver(&drv->link);
}
EXPORT_SYMBOL(pnp_unregister_card_driver);