wbsd.c

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	return -ENODEV;
}

/*
 * Allocate/free io port ranges
 */

static int __devinit wbsd_request_region(struct wbsd_host *host, int base)
{
	if (base & 0x7)
		return -EINVAL;

	if (!request_region(base, 8, DRIVER_NAME))
		return -EIO;

	host->base = base;

	return 0;
}

static void __devexit wbsd_release_regions(struct wbsd_host *host)
{
	if (host->base)
		release_region(host->base, 8);

	host->base = 0;

	if (host->config)
		release_region(host->config, 2);

	host->config = 0;
}

/*
 * Allocate/free DMA port and buffer
 */

static void __devinit wbsd_request_dma(struct wbsd_host *host, int dma)
{
	if (dma < 0)
		return;

	if (request_dma(dma, DRIVER_NAME))
		goto err;

	/*
	 * We need to allocate a special buffer in
	 * order for ISA to be able to DMA to it.
	 */
	host->dma_buffer = kmalloc(WBSD_DMA_SIZE,
		GFP_NOIO | GFP_DMA | __GFP_REPEAT | __GFP_NOWARN);
	if (!host->dma_buffer)
		goto free;

	/*
	 * Translate the address to a physical address.
	 */
	host->dma_addr = dma_map_single(mmc_dev(host->mmc), host->dma_buffer,
		WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);

	/*
	 * ISA DMA must be aligned on a 64k basis.
	 */
	if ((host->dma_addr & 0xffff) != 0)
		goto kfree;
	/*
	 * ISA cannot access memory above 16 MB.
	 */
	else if (host->dma_addr >= 0x1000000)
		goto kfree;

	host->dma = dma;

	return;

kfree:
	/*
	 * If we've gotten here then there is some kind of alignment bug
	 */
	BUG_ON(1);

	dma_unmap_single(mmc_dev(host->mmc), host->dma_addr,
		WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
	host->dma_addr = (dma_addr_t)NULL;

	kfree(host->dma_buffer);
	host->dma_buffer = NULL;

free:
	free_dma(dma);

err:
	printk(KERN_WARNING DRIVER_NAME ": Unable to allocate DMA %d. "
		"Falling back on FIFO.\n", dma);
}

static void __devexit wbsd_release_dma(struct wbsd_host *host)
{
	if (host->dma_addr) {
		dma_unmap_single(mmc_dev(host->mmc), host->dma_addr,
			WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
	}
	kfree(host->dma_buffer);
	if (host->dma >= 0)
		free_dma(host->dma);

	host->dma = -1;
	host->dma_buffer = NULL;
	host->dma_addr = (dma_addr_t)NULL;
}

/*
 * Allocate/free IRQ.
 */

static int __devinit wbsd_request_irq(struct wbsd_host *host, int irq)
{
	int ret;

	/*
	 * Allocate interrupt.
	 */

	ret = request_irq(irq, wbsd_irq, IRQF_SHARED, DRIVER_NAME, host);
	if (ret)
		return ret;

	host->irq = irq;

	/*
	 * Set up tasklets.
	 */
	tasklet_init(&host->card_tasklet, wbsd_tasklet_card,
			(unsigned long)host);
	tasklet_init(&host->fifo_tasklet, wbsd_tasklet_fifo,
			(unsigned long)host);
	tasklet_init(&host->crc_tasklet, wbsd_tasklet_crc,
			(unsigned long)host);
	tasklet_init(&host->timeout_tasklet, wbsd_tasklet_timeout,
			(unsigned long)host);
	tasklet_init(&host->finish_tasklet, wbsd_tasklet_finish,
			(unsigned long)host);
	tasklet_init(&host->block_tasklet, wbsd_tasklet_block,
			(unsigned long)host);

	return 0;
}

static void __devexit wbsd_release_irq(struct wbsd_host *host)
{
	if (!host->irq)
		return;

	free_irq(host->irq, host);

	host->irq = 0;

	tasklet_kill(&host->card_tasklet);
	tasklet_kill(&host->fifo_tasklet);
	tasklet_kill(&host->crc_tasklet);
	tasklet_kill(&host->timeout_tasklet);
	tasklet_kill(&host->finish_tasklet);
	tasklet_kill(&host->block_tasklet);
}

/*
 * Allocate all resources for the host.
 */

static int __devinit wbsd_request_resources(struct wbsd_host *host,
	int base, int irq, int dma)
{
	int ret;

	/*
	 * Allocate I/O ports.
	 */
	ret = wbsd_request_region(host, base);
	if (ret)
		return ret;

	/*
	 * Allocate interrupt.
	 */
	ret = wbsd_request_irq(host, irq);
	if (ret)
		return ret;

	/*
	 * Allocate DMA.
	 */
	wbsd_request_dma(host, dma);

	return 0;
}

/*
 * Release all resources for the host.
 */

static void __devexit wbsd_release_resources(struct wbsd_host *host)
{
	wbsd_release_dma(host);
	wbsd_release_irq(host);
	wbsd_release_regions(host);
}

/*
 * Configure the resources the chip should use.
 */

static void wbsd_chip_config(struct wbsd_host *host)
{
	wbsd_unlock_config(host);

	/*
	 * Reset the chip.
	 */
	wbsd_write_config(host, WBSD_CONF_SWRST, 1);
	wbsd_write_config(host, WBSD_CONF_SWRST, 0);

	/*
	 * Select SD/MMC function.
	 */
	wbsd_write_config(host, WBSD_CONF_DEVICE, DEVICE_SD);

	/*
	 * Set up card detection.
	 */
	wbsd_write_config(host, WBSD_CONF_PINS, WBSD_PINS_DETECT_GP11);

	/*
	 * Configure chip
	 */
	wbsd_write_config(host, WBSD_CONF_PORT_HI, host->base >> 8);
	wbsd_write_config(host, WBSD_CONF_PORT_LO, host->base & 0xff);

	wbsd_write_config(host, WBSD_CONF_IRQ, host->irq);

	if (host->dma >= 0)
		wbsd_write_config(host, WBSD_CONF_DRQ, host->dma);

	/*
	 * Enable and power up chip.
	 */
	wbsd_write_config(host, WBSD_CONF_ENABLE, 1);
	wbsd_write_config(host, WBSD_CONF_POWER, 0x20);

	wbsd_lock_config(host);
}

/*
 * Check that configured resources are correct.
 */

static int wbsd_chip_validate(struct wbsd_host *host)
{
	int base, irq, dma;

	wbsd_unlock_config(host);

	/*
	 * Select SD/MMC function.
	 */
	wbsd_write_config(host, WBSD_CONF_DEVICE, DEVICE_SD);

	/*
	 * Read configuration.
	 */
	base = wbsd_read_config(host, WBSD_CONF_PORT_HI) << 8;
	base |= wbsd_read_config(host, WBSD_CONF_PORT_LO);

	irq = wbsd_read_config(host, WBSD_CONF_IRQ);

	dma = wbsd_read_config(host, WBSD_CONF_DRQ);

	wbsd_lock_config(host);

	/*
	 * Validate against given configuration.
	 */
	if (base != host->base)
		return 0;
	if (irq != host->irq)
		return 0;
	if ((dma != host->dma) && (host->dma != -1))
		return 0;

	return 1;
}

/*
 * Powers down the SD function
 */

static void wbsd_chip_poweroff(struct wbsd_host *host)
{
	wbsd_unlock_config(host);

	wbsd_write_config(host, WBSD_CONF_DEVICE, DEVICE_SD);
	wbsd_write_config(host, WBSD_CONF_ENABLE, 0);

	wbsd_lock_config(host);
}

/*****************************************************************************\
 *                                                                           *
 * Devices setup and shutdown                                                *
 *                                                                           *
\*****************************************************************************/

static int __devinit wbsd_init(struct device *dev, int base, int irq, int dma,
	int pnp)
{
	struct wbsd_host *host = NULL;
	struct mmc_host *mmc = NULL;
	int ret;

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

	mmc = dev_get_drvdata(dev);
	host = mmc_priv(mmc);

	/*
	 * Scan for hardware.
	 */
	ret = wbsd_scan(host);
	if (ret) {
		if (pnp && (ret == -ENODEV)) {
			printk(KERN_WARNING DRIVER_NAME
				": Unable to confirm device presence. You may "
				"experience lock-ups.\n");
		} else {
			wbsd_free_mmc(dev);
			return ret;
		}
	}

	/*
	 * Request resources.
	 */
	ret = wbsd_request_resources(host, base, irq, dma);
	if (ret) {
		wbsd_release_resources(host);
		wbsd_free_mmc(dev);
		return ret;
	}

	/*
	 * See if chip needs to be configured.
	 */
	if (pnp) {
		if ((host->config != 0) && !wbsd_chip_validate(host)) {
			printk(KERN_WARNING DRIVER_NAME
				": PnP active but chip not configured! "
				"You probably have a buggy BIOS. "
				"Configuring chip manually.\n");
			wbsd_chip_config(host);
		}
	} else
		wbsd_chip_config(host);

	/*
	 * Power Management stuff. No idea how this works.
	 * Not tested.
	 */
#ifdef CONFIG_PM
	if (host->config) {
		wbsd_unlock_config(host);
		wbsd_write_config(host, WBSD_CONF_PME, 0xA0);
		wbsd_lock_config(host);
	}
#endif
	/*
	 * Allow device to initialise itself properly.
	 */
	mdelay(5);

	/*
	 * Reset the chip into a known state.
	 */
	wbsd_init_device(host);

	mmc_add_host(mmc);

	printk(KERN_INFO "%s: W83L51xD", mmc_hostname(mmc));
	if (host->chip_id != 0)
		printk(" id %x", (int)host->chip_id);
	printk(" at 0x%x irq %d", (int)host->base, (int)host->irq);
	if (host->dma >= 0)
		printk(" dma %d", (int)host->dma);
	else
		printk(" FIFO");
	if (pnp)
		printk(" PnP");
	printk("\n");

	return 0;
}

static void __devexit wbsd_shutdown(struct device *dev, int pnp)
{
	struct mmc_host *mmc = dev_get_drvdata(dev);
	struct wbsd_host *host;

	if (!mmc)
		return;

	host = mmc_priv(mmc);

	mmc_remove_host(mmc);

	/*
	 * Power down the SD/MMC function.
	 */
	if (!pnp)
		wbsd_chip_poweroff(host);

	wbsd_release_resources(host);

	wbsd_free_mmc(dev);
}

/*
 * Non-PnP
 */

static int __devinit wbsd_probe(struct platform_device *dev)
{
	/* Use the module parameters for resources */
	return wbsd_init(&dev->dev, io, irq, dma, 0);
}

static int __devexit wbsd_remove(struct platform_device *dev)
{
	wbsd_shutdown(&dev->dev, 0);

	return 0;
}

/*
 * PnP
 */

#ifdef CONFIG_PNP

static int __devinit
wbsd_pnp_probe(struct pnp_dev *pnpdev, const struct pnp_device_id *dev_id)
{
	int io, irq, dma;

	/*
	 * Get resources from PnP layer.
	 */
	io = pnp_port_start(pnpdev, 0);
	irq = pnp_irq(pnpdev, 0);
	if (pnp_dma_valid(pnpdev, 0))
		dma = pnp_dma(pnpdev, 0);
	else
		dma = -1;

	DBGF("PnP resources: port %3x irq %d dma %d\n", io, irq, dma);

	return wbsd_init(&pnpdev->dev, io, irq, dma, 1);
}

static void __devexit wbsd_pnp_remove(struct pnp_dev *dev)
{
	wbsd_shutdown(&dev->dev, 1);
}

#endif /* CONFIG_PNP */

/*
 * Power management
 */

#ifdef CONFIG_PM

static int wbsd_suspend(struct wbsd_host *host, pm_message_t state)
{
	BUG_ON(host == NULL);

	return mmc_suspend_host(host->mmc, state);
}

static int wbsd_resume(struct wbsd_host *host)
{
	BUG_ON(host == NULL);

	wbsd_init_device(host);

	return mmc_resume_host(host->mmc);
}

static int wbsd_platform_suspend(struct platform_device *dev,
				 pm_message_t state)
{
	struct mmc_host *mmc = platform_get_drvdata(dev);
	struct wbsd_host *host;
	int ret;

	if (mmc == NULL)
		return 0;

	DBGF("Suspending...\n");

	host = mmc_priv(mmc);

	ret = wbsd_suspend(host, state);
	if (ret)
		return ret;

	wbsd_chip_poweroff(host);

	return 0;
}

static int wbsd_platform_resume(struct platform_device *dev)
{
	struct mmc_host *mmc = platform_get_drvdata(dev);
	struct wbsd_host *host;

	if (mmc == NULL)
		return 0;

	DBGF("Resuming...\n");

	host = mmc_priv(mmc);

	wbsd_chip_config(host);

	/*
	 * Allow device to initialise itself properly.
	 */
	mdelay(5);

	return wbsd_resume(host);
}

#ifdef CONFIG_PNP

static int wbsd_pnp_suspend(struct pnp_dev *pnp_dev, pm_message_t state)
{
	struct mmc_host *mmc = dev_get_drvdata(&pnp_dev->dev);
	struct wbsd_host *host;

	if (mmc == NULL)
		return 0;

	DBGF("Suspending...\n");

	host = mmc_priv(mmc);

	return wbsd_suspend(host, state);
}

static int wbsd_pnp_resume(struct pnp_dev *pnp_dev)
{
	struct mmc_host *mmc = dev_get_drvdata(&pnp_dev->dev);
	struct wbsd_host *host;

	if (mmc == NULL)
		return 0;

	DBGF("Resuming...\n");

	host = mmc_priv(mmc);

	/*
	 * See if chip needs to be configured.
	 */
	if (host->config != 0) {
		if (!wbsd_chip_validate(host)) {
			printk(KERN_WARNING DRIVER_NAME
				": PnP active but chip not configured! "
				"You probably have a buggy BIOS. "
				"Configuring chip manually.\n");
			wbsd_chip_config(host);
		}
	}

	/*
	 * Allow device to initialise itself properly.
	 */
	mdelay(5);

	return wbsd_resume(host);
}

#endif /* CONFIG_PNP */

#else /* CONFIG_PM */

#define wbsd_platform_suspend NULL
#define wbsd_platform_resume NULL

#define wbsd_pnp_suspend NULL
#define wbsd_pnp_resume NULL

#endif /* CONFIG_PM */

static struct platform_device *wbsd_device;

static struct platform_driver wbsd_driver = {
	.probe		= wbsd_probe,
	.remove		= __devexit_p(wbsd_remove),

	.suspend	= wbsd_platform_suspend,
	.resume		= wbsd_platform_resume,
	.driver		= {
		.name	= DRIVER_NAME,
	},
};

#ifdef CONFIG_PNP

static struct pnp_driver wbsd_pnp_driver = {
	.name		= DRIVER_NAME,
	.id_table	= pnp_dev_table,
	.probe		= wbsd_pnp_probe,
	.remove		= __devexit_p(wbsd_pnp_remove),

	.suspend	= wbsd_pnp_suspend,
	.resume		= wbsd_pnp_resume,
};

#endif /* CONFIG_PNP */

/*
 * Module loading/unloading
 */

static int __init wbsd_drv_init(void)
{
	int result;

	printk(KERN_INFO DRIVER_NAME
		": Winbond W83L51xD SD/MMC card interface driver, "
		DRIVER_VERSION "\n");
	printk(KERN_INFO DRIVER_NAME ": Copyright(c) Pierre Ossman\n");

#ifdef CONFIG_PNP

	if (!nopnp) {
		result = pnp_register_driver(&wbsd_pnp_driver);
		if (result < 0)
			return result;
	}
#endif /* CONFIG_PNP */

	if (nopnp) {
		result = platform_driver_register(&wbsd_driver);
		if (result < 0)
			return result;

		wbsd_device = platform_device_alloc(DRIVER_NAME, -1);
		if (!wbsd_device) {
			platform_driver_unregister(&wbsd_driver);
			return -ENOMEM;
		}

		result = platform_device_add(wbsd_device);
		if (result) {
			platform_device_put(wbsd_device);
			platform_driver_unregister(&wbsd_driver);
			return result;
		}
	}

	return 0;
}

static void __exit wbsd_drv_exit(void)
{
#ifdef CONFIG_PNP

	if (!nopnp)
		pnp_unregister_driver(&wbsd_pnp_driver);

#endif /* CONFIG_PNP */

	if (nopnp) {
		platform_device_unregister(wbsd_device);

		platform_driver_unregister(&wbsd_driver);
	}

	DBG("unloaded\n");
}

module_init(wbsd_drv_init);
module_exit(wbsd_drv_exit);
#ifdef CONFIG_PNP
module_param(nopnp, uint, 0444);
#endif
module_param(io, uint, 0444);
module_param(irq, uint, 0444);
module_param(dma, int, 0444);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pierre Ossman <[e-mail]>");
MODULE_DESCRIPTION("Winbond W83L51xD SD/MMC card interface driver");
MODULE_VERSION(DRIVER_VERSION);

#ifdef CONFIG_PNP
MODULE_PARM_DESC(nopnp, "Scan for device instead of relying on PNP. (default 0)");
#endif
MODULE_PARM_DESC(io, "I/O base to allocate. Must be 8 byte aligned. (default 0x248)");
MODULE_PARM_DESC(irq, "IRQ to allocate. (default 6)");
MODULE_PARM_DESC(dma, "DMA channel to allocate. -1 for no DMA. (default 2)");