whci.c

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/*
 * WHCI UWB Multi-interface Controller enumerator.
 *
 * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
 *
 * This file is released under the GNU GPL v2.
 */
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/uwb/whci.h>
#include <linux/uwb/umc.h>

struct whci_card {
    struct pci_dev *pci;
    void __iomem *uwbbase;
    u8 n_caps;
    struct umc_dev *devs[0];
};


/* Fix faulty HW :( */
static
u64 whci_capdata_quirks(struct whci_card *card, u64 capdata)
{
    u64 capdata_orig = capdata;
    struct pci_dev *pci_dev = card->pci;
    if (pci_dev->vendor == PCI_VENDOR_ID_INTEL
        && (pci_dev->device == 0x0c3b || pci_dev->device == 0004)
        && pci_dev->class == 0x0d1010) {
        switch (UWBCAPDATA_TO_CAP_ID(capdata)) {
            /* WLP capability has 0x100 bytes of aperture */
        case 0x80:
            capdata |= 0x40 << 8; break;
            /* WUSB capability has 0x80 bytes of aperture
             * and ID is 1 */
        case 0x02:
            capdata &= ~0xffff;
            capdata |= 0x2001;
            break;
        }
    }
    if (capdata_orig != capdata)
        dev_warn(&pci_dev->dev,
             "PCI v%04x d%04x c%06x#%02x: "
             "corrected capdata from %016Lx to %016Lx\n",
             pci_dev->vendor, pci_dev->device, pci_dev->class,
             (unsigned)UWBCAPDATA_TO_CAP_ID(capdata),
             (unsigned long long)capdata_orig,
             (unsigned long long)capdata);
    return capdata;
}


int whci_wait_for(struct device *dev, u32 __iomem *reg, u32 mask, u32 result,
    unsigned long max_ms, const char *tag)
{
    unsigned t = 0;
    u32 val;
    for (;;) {
        val = le_readl(reg);
        if ((val & mask) == result)
            break;
        if (t >= max_ms) {
            dev_err(dev, "%s timed out\n", tag);
            return -ETIMEDOUT;
        }
        msleep(10);
        t += 10;
    }
    return 0;
}
EXPORT_SYMBOL_GPL(whci_wait_for);


/*
 * NOTE: the capinfo and capdata registers are slightly different
 *       (size and cap-id fields). So for cap #0, we need to fill
 *       in. Size comes from the size of the register block
 *       (statically calculated); cap_id comes from nowhere, we use
 *       zero, that is reserved, for the radio controller, because
 *       none was defined at the spec level.
 */
static int whci_add_cap(struct whci_card *card, int n)
{
    struct umc_dev *umc;
    u64 capdata;
    int bar, err;

    umc = umc_device_create(&card->pci->dev, n);
    if (umc == NULL)
        return -ENOMEM;

    capdata = le_readq(card->uwbbase + UWBCAPDATA(n));

    bar = UWBCAPDATA_TO_BAR(capdata) << 1;

    capdata = whci_capdata_quirks(card, capdata);
    /* Capability 0 is the radio controller. It's size is 32
     * bytes (WHCI0.95[2.3, T2-9]). */
    umc->version         = UWBCAPDATA_TO_VERSION(capdata);
    umc->cap_id          = n == 0 ? 0 : UWBCAPDATA_TO_CAP_ID(capdata);
    umc->bar         = bar;
    umc->resource.start  = pci_resource_start(card->pci, bar)
        + UWBCAPDATA_TO_OFFSET(capdata);
    umc->resource.end    = umc->resource.start
        + (n == 0 ? 0x20 : UWBCAPDATA_TO_SIZE(capdata)) - 1;
    umc->resource.name   = dev_name(&umc->dev);
    umc->resource.flags  = card->pci->resource[bar].flags;
    umc->resource.parent = &card->pci->resource[bar];
    umc->irq             = card->pci->irq;

    err = umc_device_register(umc);
    if (err < 0)
        goto error;
    card->devs[n] = umc;
    return 0;

error:
    kfree(umc);
    return err;
}

static void whci_del_cap(struct whci_card *card, int n)
{
    struct umc_dev *umc = card->devs[n];

    if (umc != NULL)
        umc_device_unregister(umc);
}

static int whci_n_caps(struct pci_dev *pci)
{
    void __iomem *uwbbase;
    u64 capinfo;

    uwbbase = pci_iomap(pci, 0, 8);
    if (!uwbbase)
        return -ENOMEM;
    capinfo = le_readq(uwbbase + UWBCAPINFO);
    pci_iounmap(pci, uwbbase);

    return UWBCAPINFO_TO_N_CAPS(capinfo);
}

static int whci_probe(struct pci_dev *pci, const struct pci_device_id *id)
{
    struct whci_card *card;
    int err, n_caps, n;

    err = pci_enable_device(pci);
    if (err < 0)
        goto error;
    pci_enable_msi(pci);
    pci_set_master(pci);
    err = -ENXIO;
    if (!pci_set_dma_mask(pci, DMA_BIT_MASK(64)))
        pci_set_consistent_dma_mask(pci, DMA_BIT_MASK(64));
    else if (!pci_set_dma_mask(pci, DMA_BIT_MASK(32)))
        pci_set_consistent_dma_mask(pci, DMA_BIT_MASK(32));
    else
        goto error_dma;

    err = n_caps = whci_n_caps(pci);
    if (n_caps < 0)
        goto error_ncaps;

    err = -ENOMEM;
    card = kzalloc(sizeof(struct whci_card)
               + sizeof(struct whci_dev *) * (n_caps + 1),
               GFP_KERNEL);
    if (card == NULL)
        goto error_kzalloc;
    card->pci = pci;
    card->n_caps = n_caps;

    err = -EBUSY;
    if (!request_mem_region(pci_resource_start(pci, 0),
                UWBCAPDATA_SIZE(card->n_caps),
                "whci (capability data)"))
        goto error_request_memregion;
    err = -ENOMEM;
    card->uwbbase = pci_iomap(pci, 0, UWBCAPDATA_SIZE(card->n_caps));
    if (!card->uwbbase)
        goto error_iomap;

    /* Add each capability. */
    for (n = 0; n <= card->n_caps; n++) {
        err = whci_add_cap(card, n);
        if (err < 0 && n == 0) {
            dev_err(&pci->dev, "cannot bind UWB radio controller:"
                " %d\n", err);
            goto error_bind;
        }
        if (err < 0)
            dev_warn(&pci->dev, "warning: cannot bind capability "
                 "#%u: %d\n", n, err);
    }
    pci_set_drvdata(pci, card);
    return 0;

error_bind:
    pci_iounmap(pci, card->uwbbase);
error_iomap:
    release_mem_region(pci_resource_start(pci, 0), UWBCAPDATA_SIZE(card->n_caps));
error_request_memregion:
    kfree(card);
error_kzalloc:
error_ncaps:
error_dma:
    pci_disable_msi(pci);
    pci_disable_device(pci);
error:
    return err;
}

static void whci_remove(struct pci_dev *pci)
{
    struct whci_card *card = pci_get_drvdata(pci);
    int n;

    pci_set_drvdata(pci, NULL);
    /* Unregister each capability in reverse (so the master device
     * is unregistered last). */
    for (n = card->n_caps; n >= 0 ; n--)
        whci_del_cap(card, n);
    pci_iounmap(pci, card->uwbbase);
    release_mem_region(pci_resource_start(pci, 0), UWBCAPDATA_SIZE(card->n_caps));
    kfree(card);
    pci_disable_msi(pci);
    pci_disable_device(pci);
}

static struct pci_device_id whci_id_table[] = {
    { PCI_DEVICE_CLASS(PCI_CLASS_WIRELESS_WHCI, ~0) },
    { 0 },
};
MODULE_DEVICE_TABLE(pci, whci_id_table);


static struct pci_driver whci_driver = {
    .name     = "whci",
    .id_table = whci_id_table,
    .probe    = whci_probe,
    .remove   = whci_remove,
};

static int __init whci_init(void)
{
    return pci_register_driver(&whci_driver);
}

static void __exit whci_exit(void)
{
    pci_unregister_driver(&whci_driver);
}

module_init(whci_init);
module_exit(whci_exit);

MODULE_DESCRIPTION("WHCI UWB Multi-interface Controller enumerator");
MODULE_AUTHOR("Cambridge Silicon Radio Ltd.");
MODULE_LICENSE("GPL");