// SPDX-License-Identifier: GPL-2.0-only
/*
 * cardbus.c -- 16-bit PCMCIA core support
 *
 * 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.
 *
 * (C) 1999             David A. Hinds
 */

/*
 * Cardbus handling has been re-written to be more of a PCI bridge thing,
 * and the PCI code basically does all the resource handling.
 *
 *              Linus, Jan 2000
 */


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>

#include <pcmcia/ss.h>
#include <pcmcia/cistpl.h>

#include "cs_internal.h"

static void cardbus_config_irq_and_cls(struct pci_bus *bus, int irq)
{
        struct pci_dev *dev;

        list_for_each_entry(dev, &bus->devices, bus_list) {
                u8 irq_pin;

                /*
                 * Since there is only one interrupt available to
                 * CardBus devices, all devices downstream of this
                 * device must be using this IRQ.
                 */
                pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq_pin);
                if (irq_pin) {
                        dev->irq = irq;
                        pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
                }

                /*
                 * Some controllers transfer very slowly with 0 CLS.
                 * Configure it.  This may fail as CLS configuration
                 * is mandatory only for MWI.
                 */
                pci_set_cacheline_size(dev);

                if (dev->subordinate)
                        cardbus_config_irq_and_cls(dev->subordinate, irq);
        }
}

/**
 * cb_alloc() - add CardBus device
 * @s:          the pcmcia_socket where the CardBus device is located
 *
 * cb_alloc() allocates the kernel data structures for a Cardbus device
 * and handles the lowest level PCI device setup issues.
 */
int __ref cb_alloc(struct pcmcia_socket *s)
{
        struct pci_bus *bus = s->cb_dev->subordinate;
        struct pci_dev *dev;
        unsigned int max, pass;

        pci_lock_rescan_remove();

        s->functions = pci_scan_slot(bus, PCI_DEVFN(0, 0));

        max = bus->busn_res.start;
        for (pass = 0; pass < 2; pass++)
                for_each_pci_bridge(dev, bus)
                        max = pci_scan_bridge(bus, dev, max, pass);

        /*
         * Size all resources below the CardBus controller.
         */
        pci_bus_size_bridges(bus);
        pci_bus_assign_resources(bus);
        cardbus_config_irq_and_cls(bus, s->pci_irq);

        /* socket specific tune function */
        if (s->tune_bridge)
                s->tune_bridge(s, bus);

        pci_bus_add_devices(bus);

        pci_unlock_rescan_remove();
        return 0;
}

/**
 * cb_free() - remove CardBus device
 * @s:          the pcmcia_socket where the CardBus device was located
 *
 * cb_free() handles the lowest level PCI device cleanup.
 */
void cb_free(struct pcmcia_socket *s)
{
        struct pci_dev *bridge, *dev, *tmp;
        struct pci_bus *bus;

        bridge = s->cb_dev;
        if (!bridge)
                return;

        bus = bridge->subordinate;
        if (!bus)
                return;

        pci_lock_rescan_remove();

        list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list)
                pci_stop_and_remove_bus_device(dev);

        pci_unlock_rescan_remove();
}