spi-pxa2xx-pci.c

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/*
 * CE4100's SPI device is more or less the same one as found on PXA
 *
 */
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/module.h>
#include <linux/spi/pxa2xx_spi.h>

struct ce4100_info {
    struct ssp_device ssp;
    struct platform_device *spi_pdev;
};

static DEFINE_MUTEX(ssp_lock);
static LIST_HEAD(ssp_list);

struct ssp_device *pxa_ssp_request(int port, const char *label)
{
    struct ssp_device *ssp = NULL;

    mutex_lock(&ssp_lock);

    list_for_each_entry(ssp, &ssp_list, node) {
        if (ssp->port_id == port && ssp->use_count == 0) {
            ssp->use_count++;
            ssp->label = label;
            break;
        }
    }

    mutex_unlock(&ssp_lock);

    if (&ssp->node == &ssp_list)
        return NULL;

    return ssp;
}
EXPORT_SYMBOL_GPL(pxa_ssp_request);

void pxa_ssp_free(struct ssp_device *ssp)
{
    mutex_lock(&ssp_lock);
    if (ssp->use_count) {
        ssp->use_count--;
        ssp->label = NULL;
    } else
        dev_err(&ssp->pdev->dev, "device already free\n");
    mutex_unlock(&ssp_lock);
}
EXPORT_SYMBOL_GPL(pxa_ssp_free);

static int __devinit ce4100_spi_probe(struct pci_dev *dev,
        const struct pci_device_id *ent)
{
    int ret;
    resource_size_t phys_beg;
    resource_size_t phys_len;
    struct ce4100_info *spi_info;
    struct platform_device *pdev;
    struct pxa2xx_spi_master spi_pdata;
    struct ssp_device *ssp;

    ret = pci_enable_device(dev);
    if (ret)
        return ret;

    phys_beg = pci_resource_start(dev, 0);
    phys_len = pci_resource_len(dev, 0);

    if (!request_mem_region(phys_beg, phys_len,
                "CE4100 SPI")) {
        dev_err(&dev->dev, "Can't request register space.\n");
        ret = -EBUSY;
        return ret;
    }

    pdev = platform_device_alloc("pxa2xx-spi", dev->devfn);
    spi_info = kzalloc(sizeof(*spi_info), GFP_KERNEL);
    if (!pdev || !spi_info ) {
        ret = -ENOMEM;
        goto err_nomem;
    }
    memset(&spi_pdata, 0, sizeof(spi_pdata));
    spi_pdata.num_chipselect = dev->devfn;

    ret = platform_device_add_data(pdev, &spi_pdata, sizeof(spi_pdata));
    if (ret)
        goto err_nomem;

    pdev->dev.parent = &dev->dev;
    pdev->dev.of_node = dev->dev.of_node;
    ssp = &spi_info->ssp;
    ssp->phys_base = pci_resource_start(dev, 0);
    ssp->mmio_base = ioremap(phys_beg, phys_len);
    if (!ssp->mmio_base) {
        dev_err(&pdev->dev, "failed to ioremap() registers\n");
        ret = -EIO;
        goto err_nomem;
    }
    ssp->irq = dev->irq;
    ssp->port_id = pdev->id;
    ssp->type = PXA25x_SSP;

    mutex_lock(&ssp_lock);
    list_add(&ssp->node, &ssp_list);
    mutex_unlock(&ssp_lock);

    pci_set_drvdata(dev, spi_info);

    ret = platform_device_add(pdev);
    if (ret)
        goto err_dev_add;

    return ret;

err_dev_add:
    pci_set_drvdata(dev, NULL);
    mutex_lock(&ssp_lock);
    list_del(&ssp->node);
    mutex_unlock(&ssp_lock);
    iounmap(ssp->mmio_base);

err_nomem:
    release_mem_region(phys_beg, phys_len);
    platform_device_put(pdev);
    kfree(spi_info);
    return ret;
}

static void __devexit ce4100_spi_remove(struct pci_dev *dev)
{
    struct ce4100_info *spi_info;
    struct ssp_device *ssp;

    spi_info = pci_get_drvdata(dev);
    ssp = &spi_info->ssp;
    platform_device_unregister(spi_info->spi_pdev);

    iounmap(ssp->mmio_base);
    release_mem_region(pci_resource_start(dev, 0),
            pci_resource_len(dev, 0));

    mutex_lock(&ssp_lock);
    list_del(&ssp->node);
    mutex_unlock(&ssp_lock);

    pci_set_drvdata(dev, NULL);
    pci_disable_device(dev);
    kfree(spi_info);
}

static DEFINE_PCI_DEVICE_TABLE(ce4100_spi_devices) = {
    { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e6a) },
    { },
};
MODULE_DEVICE_TABLE(pci, ce4100_spi_devices);

static struct pci_driver ce4100_spi_driver = {
    .name           = "ce4100_spi",
    .id_table       = ce4100_spi_devices,
    .probe          = ce4100_spi_probe,
    .remove         = __devexit_p(ce4100_spi_remove),
};

module_pci_driver(ce4100_spi_driver);

MODULE_DESCRIPTION("CE4100 PCI-SPI glue code for PXA's driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Sebastian Andrzej Siewior <[email protected]>");