// SPDX-License-Identifier: GPL-2.0-only
/*
 * speedfax.c   low level stuff for Sedlbauer Speedfax+ cards
 *              based on the ISAR DSP
 *              Thanks to Sedlbauer AG for informations and HW
 *
 * Author       Karsten Keil <keil@isdn4linux.de>
 *
 * Copyright 2009  by Karsten Keil <keil@isdn4linux.de>
 */

#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/mISDNhw.h>
#include <linux/firmware.h>
#include "ipac.h"
#include "isar.h"

#define SPEEDFAX_REV    "2.0"

#define PCI_SUBVENDOR_SPEEDFAX_PYRAMID  0x51
#define PCI_SUBVENDOR_SPEEDFAX_PCI      0x54
#define PCI_SUB_ID_SEDLBAUER            0x01

#define SFAX_PCI_ADDR           0xc8
#define SFAX_PCI_ISAC           0xd0
#define SFAX_PCI_ISAR           0xe0

/* TIGER 100 Registers */

#define TIGER_RESET_ADDR        0x00
#define TIGER_EXTERN_RESET_ON   0x01
#define TIGER_EXTERN_RESET_OFF  0x00
#define TIGER_AUX_CTRL          0x02
#define TIGER_AUX_DATA          0x03
#define TIGER_AUX_IRQMASK       0x05
#define TIGER_AUX_STATUS        0x07

/* Tiger AUX BITs */
#define SFAX_AUX_IOMASK         0xdd    /* 1 and 5 are inputs */
#define SFAX_ISAR_RESET_BIT_OFF 0x00
#define SFAX_ISAR_RESET_BIT_ON  0x01
#define SFAX_TIGER_IRQ_BIT      0x02
#define SFAX_LED1_BIT           0x08
#define SFAX_LED2_BIT           0x10

#define SFAX_PCI_RESET_ON       (SFAX_ISAR_RESET_BIT_ON)
#define SFAX_PCI_RESET_OFF      (SFAX_LED1_BIT | SFAX_LED2_BIT)

static int sfax_cnt;
static u32 debug;
static u32 irqloops = 4;

struct sfax_hw {
        struct list_head        list;
        struct pci_dev          *pdev;
        char                    name[MISDN_MAX_IDLEN];
        u32                     irq;
        u32                     irqcnt;
        u32                     cfg;
        struct _ioport          p_isac;
        struct _ioport          p_isar;
        u8                      aux_data;
        spinlock_t              lock;   /* HW access lock */
        struct isac_hw          isac;
        struct isar_hw          isar;
};

static LIST_HEAD(Cards);
static DEFINE_RWLOCK(card_lock); /* protect Cards */

static void
_set_debug(struct sfax_hw *card)
{
        card->isac.dch.debug = debug;
        card->isar.ch[0].bch.debug = debug;
        card->isar.ch[1].bch.debug = debug;
}

static int
set_debug(const char *val, const struct kernel_param *kp)
{
        int ret;
        struct sfax_hw *card;

        ret = param_set_uint(val, kp);
        if (!ret) {
                read_lock(&card_lock);
                list_for_each_entry(card, &Cards, list)
                        _set_debug(card);
                read_unlock(&card_lock);
        }
        return ret;
}

MODULE_AUTHOR("Karsten Keil");
MODULE_DESCRIPTION("mISDN driver for Sedlbauer Speedfax+ cards");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(SPEEDFAX_REV);
MODULE_FIRMWARE("isdn/ISAR.BIN");
module_param_call(debug, set_debug, param_get_uint, &debug, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Speedfax debug mask");
module_param(irqloops, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(irqloops, "Speedfax maximal irqloops (default 4)");

IOFUNC_IND(ISAC, sfax_hw, p_isac)
IOFUNC_IND(ISAR, sfax_hw, p_isar)

static irqreturn_t
speedfax_irq(int intno, void *dev_id)
{
        struct sfax_hw  *sf = dev_id;
        u8 val;
        int cnt = irqloops;

        spin_lock(&sf->lock);
        val = inb(sf->cfg + TIGER_AUX_STATUS);
        if (val & SFAX_TIGER_IRQ_BIT) { /* for us or shared ? */
                spin_unlock(&sf->lock);
                return IRQ_NONE; /* shared */
        }
        sf->irqcnt++;
        val = ReadISAR_IND(sf, ISAR_IRQBIT);
Start_ISAR:
        if (val & ISAR_IRQSTA)
                mISDNisar_irq(&sf->isar);
        val = ReadISAC_IND(sf, ISAC_ISTA);
        if (val)
                mISDNisac_irq(&sf->isac, val);
        val = ReadISAR_IND(sf, ISAR_IRQBIT);
        if ((val & ISAR_IRQSTA) && cnt--)
                goto Start_ISAR;
        if (cnt < irqloops)
                pr_debug("%s: %d irqloops cpu%d\n", sf->name,
                         irqloops - cnt, smp_processor_id());
        if (irqloops && !cnt)
                pr_notice("%s: %d IRQ LOOP cpu%d\n", sf->name,
                          irqloops, smp_processor_id());
        spin_unlock(&sf->lock);
        return IRQ_HANDLED;
}

static void
enable_hwirq(struct sfax_hw *sf)
{
        WriteISAC_IND(sf, ISAC_MASK, 0);
        WriteISAR_IND(sf, ISAR_IRQBIT, ISAR_IRQMSK);
        outb(SFAX_TIGER_IRQ_BIT, sf->cfg + TIGER_AUX_IRQMASK);
}

static void
disable_hwirq(struct sfax_hw *sf)
{
        WriteISAC_IND(sf, ISAC_MASK, 0xFF);
        WriteISAR_IND(sf, ISAR_IRQBIT, 0);
        outb(0, sf->cfg + TIGER_AUX_IRQMASK);
}

static void
reset_speedfax(struct sfax_hw *sf)
{

        pr_debug("%s: resetting card\n", sf->name);
        outb(TIGER_EXTERN_RESET_ON, sf->cfg + TIGER_RESET_ADDR);
        outb(SFAX_PCI_RESET_ON, sf->cfg + TIGER_AUX_DATA);
        mdelay(1);
        outb(TIGER_EXTERN_RESET_OFF, sf->cfg + TIGER_RESET_ADDR);
        sf->aux_data = SFAX_PCI_RESET_OFF;
        outb(sf->aux_data, sf->cfg + TIGER_AUX_DATA);
        mdelay(1);
}

static int
sfax_ctrl(struct sfax_hw  *sf, u32 cmd, u_long arg)
{
        int ret = 0;

        switch (cmd) {
        case HW_RESET_REQ:
                reset_speedfax(sf);
                break;
        case HW_ACTIVATE_IND:
                if (arg & 1)
                        sf->aux_data &= ~SFAX_LED1_BIT;
                if (arg & 2)
                        sf->aux_data &= ~SFAX_LED2_BIT;
                outb(sf->aux_data, sf->cfg + TIGER_AUX_DATA);
                break;
        case HW_DEACT_IND:
                if (arg & 1)
                        sf->aux_data |= SFAX_LED1_BIT;
                if (arg & 2)
                        sf->aux_data |= SFAX_LED2_BIT;
                outb(sf->aux_data, sf->cfg + TIGER_AUX_DATA);
                break;
        default:
                pr_info("%s: %s unknown command %x %lx\n",
                        sf->name, __func__, cmd, arg);
                ret = -EINVAL;
                break;
        }
        return ret;
}

static int
channel_ctrl(struct sfax_hw  *sf, struct mISDN_ctrl_req *cq)
{
        int     ret = 0;

        switch (cq->op) {
        case MISDN_CTRL_GETOP:
                cq->op = MISDN_CTRL_LOOP | MISDN_CTRL_L1_TIMER3;
                break;
        case MISDN_CTRL_LOOP:
                /* cq->channel: 0 disable, 1 B1 loop 2 B2 loop, 3 both */
                if (cq->channel < 0 || cq->channel > 3) {
                        ret = -EINVAL;
                        break;
                }
                ret = sf->isac.ctrl(&sf->isac, HW_TESTLOOP, cq->channel);
                break;
        case MISDN_CTRL_L1_TIMER3:
                ret = sf->isac.ctrl(&sf->isac, HW_TIMER3_VALUE, cq->p1);
                break;
        default:
                pr_info("%s: unknown Op %x\n", sf->name, cq->op);
                ret = -EINVAL;
                break;
        }
        return ret;
}

static int
sfax_dctrl(struct mISDNchannel *ch, u32 cmd, void *arg)
{
        struct mISDNdevice      *dev = container_of(ch, struct mISDNdevice, D);
        struct dchannel         *dch = container_of(dev, struct dchannel, dev);
        struct sfax_hw          *sf = dch->hw;
        struct channel_req      *rq;
        int                     err = 0;

        pr_debug("%s: cmd:%x %p\n", sf->name, cmd, arg);
        switch (cmd) {
        case OPEN_CHANNEL:
                rq = arg;
                if (rq->protocol == ISDN_P_TE_S0)
                        err = sf->isac.open(&sf->isac, rq);
                else
                        err = sf->isar.open(&sf->isar, rq);
                if (err)
                        break;
                if (!try_module_get(THIS_MODULE))
                        pr_info("%s: cannot get module\n", sf->name);
                break;
        case CLOSE_CHANNEL:
                pr_debug("%s: dev(%d) close from %p\n", sf->name,
                         dch->dev.id, __builtin_return_address(0));
                module_put(THIS_MODULE);
                break;
        case CONTROL_CHANNEL:
                err = channel_ctrl(sf, arg);
                break;
        default:
                pr_debug("%s: unknown command %x\n", sf->name, cmd);
                return -EINVAL;
        }
        return err;
}

static int
init_card(struct sfax_hw *sf)
{
        int     ret, cnt = 3;
        u_long  flags;

        ret = request_irq(sf->irq, speedfax_irq, IRQF_SHARED, sf->name, sf);
        if (ret) {
                pr_info("%s: couldn't get interrupt %d\n", sf->name, sf->irq);
                return ret;
        }
        while (cnt--) {
                spin_lock_irqsave(&sf->lock, flags);
                ret = sf->isac.init(&sf->isac);
                if (ret) {
                        spin_unlock_irqrestore(&sf->lock, flags);
                        pr_info("%s: ISAC init failed with %d\n",
                                sf->name, ret);
                        break;
                }
                enable_hwirq(sf);
                /* RESET Receiver and Transmitter */
                WriteISAC_IND(sf, ISAC_CMDR, 0x41);
                spin_unlock_irqrestore(&sf->lock, flags);
                msleep_interruptible(10);
                if (debug & DEBUG_HW)
                        pr_notice("%s: IRQ %d count %d\n", sf->name,
                                  sf->irq, sf->irqcnt);
                if (!sf->irqcnt) {
                        pr_info("%s: IRQ(%d) got no requests during init %d\n",
                                sf->name, sf->irq, 3 - cnt);
                } else
                        return 0;
        }
        free_irq(sf->irq, sf);
        return -EIO;
}


static int
setup_speedfax(struct sfax_hw *sf)
{
        u_long flags;

        if (!request_region(sf->cfg, 256, sf->name)) {
                pr_info("mISDN: %s config port %x-%x already in use\n",
                        sf->name, sf->cfg, sf->cfg + 255);
                return -EIO;
        }
        outb(0xff, sf->cfg);
        outb(0, sf->cfg);
        outb(0xdd, sf->cfg + TIGER_AUX_CTRL);
        outb(0, sf->cfg + TIGER_AUX_IRQMASK);

        sf->isac.type = IPAC_TYPE_ISAC;
        sf->p_isac.ale = sf->cfg + SFAX_PCI_ADDR;
        sf->p_isac.port = sf->cfg + SFAX_PCI_ISAC;
        sf->p_isar.ale = sf->cfg + SFAX_PCI_ADDR;
        sf->p_isar.port = sf->cfg + SFAX_PCI_ISAR;
        ASSIGN_FUNC(IND, ISAC, sf->isac);
        ASSIGN_FUNC(IND, ISAR, sf->isar);
        spin_lock_irqsave(&sf->lock, flags);
        reset_speedfax(sf);
        disable_hwirq(sf);
        spin_unlock_irqrestore(&sf->lock, flags);
        return 0;
}

static void
release_card(struct sfax_hw *card) {
        u_long  flags;

        spin_lock_irqsave(&card->lock, flags);
        disable_hwirq(card);
        spin_unlock_irqrestore(&card->lock, flags);
        card->isac.release(&card->isac);
        free_irq(card->irq, card);
        card->isar.release(&card->isar);
        mISDN_unregister_device(&card->isac.dch.dev);
        release_region(card->cfg, 256);
        pci_disable_device(card->pdev);
        pci_set_drvdata(card->pdev, NULL);
        write_lock_irqsave(&card_lock, flags);
        list_del(&card->list);
        write_unlock_irqrestore(&card_lock, flags);
        kfree(card);
        sfax_cnt--;
}

static int
setup_instance(struct sfax_hw *card)
{
        const struct firmware *firmware;
        int i, err;
        u_long flags;

        snprintf(card->name, MISDN_MAX_IDLEN - 1, "Speedfax.%d", sfax_cnt + 1);
        write_lock_irqsave(&card_lock, flags);
        list_add_tail(&card->list, &Cards);
        write_unlock_irqrestore(&card_lock, flags);
        _set_debug(card);
        spin_lock_init(&card->lock);
        card->isac.hwlock = &card->lock;
        card->isar.hwlock = &card->lock;
        card->isar.ctrl = (void *)&sfax_ctrl;
        card->isac.name = card->name;
        card->isar.name = card->name;
        card->isar.owner = THIS_MODULE;

        err = request_firmware(&firmware, "isdn/ISAR.BIN", &card->pdev->dev);
        if (err < 0) {
                pr_info("%s: firmware request failed %d\n",
                        card->name, err);
                goto error_fw;
        }
        if (debug & DEBUG_HW)
                pr_notice("%s: got firmware %zu bytes\n",
                          card->name, firmware->size);

        mISDNisac_init(&card->isac, card);

        card->isac.dch.dev.D.ctrl = sfax_dctrl;
        card->isac.dch.dev.Bprotocols =
                mISDNisar_init(&card->isar, card);
        for (i = 0; i < 2; i++) {
                set_channelmap(i + 1, card->isac.dch.dev.channelmap);
                list_add(&card->isar.ch[i].bch.ch.list,
                         &card->isac.dch.dev.bchannels);
        }

        err = setup_speedfax(card);
        if (err)
                goto error_setup;
        err = card->isar.init(&card->isar);
        if (err)
                goto error;
        err = mISDN_register_device(&card->isac.dch.dev,
                                    &card->pdev->dev, card->name);
        if (err)
                goto error;
        err = init_card(card);
        if (err)
                goto error_init;
        err = card->isar.firmware(&card->isar, firmware->data, firmware->size);
        if (!err)  {
                release_firmware(firmware);
                sfax_cnt++;
                pr_notice("SpeedFax %d cards installed\n", sfax_cnt);
                return 0;
        }
        disable_hwirq(card);
        free_irq(card->irq, card);
error_init:
        mISDN_unregister_device(&card->isac.dch.dev);
error:
        release_region(card->cfg, 256);
error_setup:
        card->isac.release(&card->isac);
        card->isar.release(&card->isar);
        release_firmware(firmware);
error_fw:
        pci_disable_device(card->pdev);
        write_lock_irqsave(&card_lock, flags);
        list_del(&card->list);
        write_unlock_irqrestore(&card_lock, flags);
        kfree(card);
        return err;
}

static int
sfaxpci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        int err = -ENOMEM;
        struct sfax_hw *card = kzalloc_obj(struct sfax_hw);

        if (!card) {
                pr_info("No memory for Speedfax+ PCI\n");
                return err;
        }
        card->pdev = pdev;
        err = pci_enable_device(pdev);
        if (err) {
                kfree(card);
                return err;
        }

        pr_notice("mISDN: Speedfax found adapter %s at %s\n",
                  (char *)ent->driver_data, pci_name(pdev));

        card->cfg = pci_resource_start(pdev, 0);
        card->irq = pdev->irq;
        pci_set_drvdata(pdev, card);
        err = setup_instance(card);
        if (err)
                pci_set_drvdata(pdev, NULL);
        return err;
}

static void
sfax_remove_pci(struct pci_dev *pdev)
{
        struct sfax_hw  *card = pci_get_drvdata(pdev);

        if (card)
                release_card(card);
        else
                pr_debug("%s: drvdata already removed\n", __func__);
}

static struct pci_device_id sfaxpci_ids[] = {
        { PCI_VENDOR_ID_TIGERJET, PCI_DEVICE_ID_TIGERJET_100,
          PCI_SUBVENDOR_SPEEDFAX_PYRAMID, PCI_SUB_ID_SEDLBAUER,
          0, 0, (unsigned long) "Pyramid Speedfax + PCI"
        },
        { PCI_VENDOR_ID_TIGERJET, PCI_DEVICE_ID_TIGERJET_100,
          PCI_SUBVENDOR_SPEEDFAX_PCI, PCI_SUB_ID_SEDLBAUER,
          0, 0, (unsigned long) "Sedlbauer Speedfax + PCI"
        },
        { }
};
MODULE_DEVICE_TABLE(pci, sfaxpci_ids);

static struct pci_driver sfaxpci_driver = {
        .name = "speedfax+ pci",
        .probe = sfaxpci_probe,
        .remove = sfax_remove_pci,
        .id_table = sfaxpci_ids,
};

static int __init
Speedfax_init(void)
{
        int err;

        pr_notice("Sedlbauer Speedfax+ Driver Rev. %s\n",
                  SPEEDFAX_REV);
        err = pci_register_driver(&sfaxpci_driver);
        return err;
}

static void __exit
Speedfax_cleanup(void)
{
        pci_unregister_driver(&sfaxpci_driver);
}

module_init(Speedfax_init);
module_exit(Speedfax_cleanup);