sdhci.c

《linux驱动程序设计从入门到精通》一书中所有的程序代码含驱动和相应的应用程序

	}

	intmask &= ~(SDHCI_INT_CMD_MASK | SDHCI_INT_DATA_MASK);

	if (intmask & SDHCI_INT_BUS_POWER) {
		printk(KERN_ERR "%s: Card is consuming too much power!\n",
			mmc_hostname(host->mmc));
		writel(SDHCI_INT_BUS_POWER, host->ioaddr + SDHCI_INT_STATUS);
	}

	intmask &= SDHCI_INT_BUS_POWER;

	if (intmask) {
		printk(KERN_ERR "%s: Unexpected interrupt 0x%08x. Please "
			"report this to " BUGMAIL ".\n",
			mmc_hostname(host->mmc), intmask);
		sdhci_dumpregs(host);

		writel(intmask, host->ioaddr + SDHCI_INT_STATUS);
	}

	result = IRQ_HANDLED;

	mmiowb();
out:
	spin_unlock(&host->lock);

	return result;
}

/*****************************************************************************\
 *                                                                           *
 * Suspend/resume                                                            *
 *                                                                           *
\*****************************************************************************/

#ifdef CONFIG_PM

static int sdhci_suspend (struct pci_dev *pdev, pm_message_t state)
{
	struct sdhci_chip *chip;
	int i, ret;

	chip = pci_get_drvdata(pdev);
	if (!chip)
		return 0;

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

	for (i = 0;i < chip->num_slots;i++) {
		if (!chip->hosts[i])
			continue;
		ret = mmc_suspend_host(chip->hosts[i]->mmc, state);
		if (ret) {
			for (i--;i >= 0;i--)
				mmc_resume_host(chip->hosts[i]->mmc);
			return ret;
		}
	}

	pci_save_state(pdev);
	pci_enable_wake(pdev, pci_choose_state(pdev, state), 0);
	pci_disable_device(pdev);
	pci_set_power_state(pdev, pci_choose_state(pdev, state));

	return 0;
}

static int sdhci_resume (struct pci_dev *pdev)
{
	struct sdhci_chip *chip;
	int i, ret;

	chip = pci_get_drvdata(pdev);
	if (!chip)
		return 0;

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

	pci_set_power_state(pdev, PCI_D0);
	pci_restore_state(pdev);
	pci_enable_device(pdev);

	for (i = 0;i < chip->num_slots;i++) {
		if (!chip->hosts[i])
			continue;
		if (chip->hosts[i]->flags & SDHCI_USE_DMA)
			pci_set_master(pdev);
		sdhci_init(chip->hosts[i]);
		mmiowb();
		ret = mmc_resume_host(chip->hosts[i]->mmc);
		if (ret)
			return ret;
	}

	return 0;
}

#else /* CONFIG_PM */

#define sdhci_suspend NULL
#define sdhci_resume NULL

#endif /* CONFIG_PM */

/*****************************************************************************\
 *                                                                           *
 * Device probing/removal                                                    *
 *                                                                           *
\*****************************************************************************/

static int __devinit sdhci_probe_slot(struct pci_dev *pdev, int slot)
{
	int ret;
	unsigned int version;
	struct sdhci_chip *chip;
	struct mmc_host *mmc;
	struct sdhci_host *host;

	u8 first_bar;
	unsigned int caps;

	chip = pci_get_drvdata(pdev);
	BUG_ON(!chip);

	ret = pci_read_config_byte(pdev, PCI_SLOT_INFO, &first_bar);
	if (ret)
		return ret;

	first_bar &= PCI_SLOT_INFO_FIRST_BAR_MASK;

	if (first_bar > 5) {
		printk(KERN_ERR DRIVER_NAME ": Invalid first BAR. Aborting.\n");
		return -ENODEV;
	}

	if (!(pci_resource_flags(pdev, first_bar + slot) & IORESOURCE_MEM)) {
		printk(KERN_ERR DRIVER_NAME ": BAR is not iomem. Aborting.\n");
		return -ENODEV;
	}

	if (pci_resource_len(pdev, first_bar + slot) != 0x100) {
		printk(KERN_ERR DRIVER_NAME ": Invalid iomem size. "
			"You may experience problems.\n");
	}

	if ((pdev->class & 0x0000FF) == PCI_SDHCI_IFVENDOR) {
		printk(KERN_ERR DRIVER_NAME ": Vendor specific interface. Aborting.\n");
		return -ENODEV;
	}

	if ((pdev->class & 0x0000FF) > PCI_SDHCI_IFVENDOR) {
		printk(KERN_ERR DRIVER_NAME ": Unknown interface. Aborting.\n");
		return -ENODEV;
	}

	mmc = mmc_alloc_host(sizeof(struct sdhci_host), &pdev->dev);
	if (!mmc)
		return -ENOMEM;

	host = mmc_priv(mmc);
	host->mmc = mmc;

	host->chip = chip;
	chip->hosts[slot] = host;

	host->bar = first_bar + slot;

	host->addr = pci_resource_start(pdev, host->bar);
	host->irq = pdev->irq;

	DBG("slot %d at 0x%08lx, irq %d\n", slot, host->addr, host->irq);

	snprintf(host->slot_descr, 20, "sdhci:slot%d", slot);

	ret = pci_request_region(pdev, host->bar, host->slot_descr);
	if (ret)
		goto free;

	host->ioaddr = ioremap_nocache(host->addr,
		pci_resource_len(pdev, host->bar));
	if (!host->ioaddr) {
		ret = -ENOMEM;
		goto release;
	}

	sdhci_reset(host, SDHCI_RESET_ALL);

	version = readw(host->ioaddr + SDHCI_HOST_VERSION);
	version = (version & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT;
	if (version != 0) {
		printk(KERN_ERR "%s: Unknown controller version (%d). "
			"You may experience problems.\n", host->slot_descr,
			version);
	}

	caps = readl(host->ioaddr + SDHCI_CAPABILITIES);

	if (debug_nodma)
		DBG("DMA forced off\n");
	else if (debug_forcedma) {
		DBG("DMA forced on\n");
		host->flags |= SDHCI_USE_DMA;
	} else if (chip->quirks & SDHCI_QUIRK_FORCE_DMA)
		host->flags |= SDHCI_USE_DMA;
	else if ((pdev->class & 0x0000FF) != PCI_SDHCI_IFDMA)
		DBG("Controller doesn't have DMA interface\n");
	else if (!(caps & SDHCI_CAN_DO_DMA))
		DBG("Controller doesn't have DMA capability\n");
	else
		host->flags |= SDHCI_USE_DMA;

	if (host->flags & SDHCI_USE_DMA) {
		if (pci_set_dma_mask(pdev, DMA_32BIT_MASK)) {
			printk(KERN_WARNING "%s: No suitable DMA available. "
				"Falling back to PIO.\n", host->slot_descr);
			host->flags &= ~SDHCI_USE_DMA;
		}
	}

	if (host->flags & SDHCI_USE_DMA)
		pci_set_master(pdev);
	else /* XXX: Hack to get MMC layer to avoid highmem */
		pdev->dma_mask = 0;

	host->max_clk =
		(caps & SDHCI_CLOCK_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
	if (host->max_clk == 0) {
		printk(KERN_ERR "%s: Hardware doesn't specify base clock "
			"frequency.\n", host->slot_descr);
		ret = -ENODEV;
		goto unmap;
	}
	host->max_clk *= 1000000;

	host->timeout_clk =
		(caps & SDHCI_TIMEOUT_CLK_MASK) >> SDHCI_TIMEOUT_CLK_SHIFT;
	if (host->timeout_clk == 0) {
		printk(KERN_ERR "%s: Hardware doesn't specify timeout clock "
			"frequency.\n", host->slot_descr);
		ret = -ENODEV;
		goto unmap;
	}
	if (caps & SDHCI_TIMEOUT_CLK_UNIT)
		host->timeout_clk *= 1000;

	host->max_block = (caps & SDHCI_MAX_BLOCK_MASK) >> SDHCI_MAX_BLOCK_SHIFT;
	if (host->max_block >= 3) {
		printk(KERN_ERR "%s: Invalid maximum block size.\n",
			host->slot_descr);
		ret = -ENODEV;
		goto unmap;
	}
	host->max_block = 512 << host->max_block;

	/*
	 * Set host parameters.
	 */
	mmc->ops = &sdhci_ops;
	mmc->f_min = host->max_clk / 256;
	mmc->f_max = host->max_clk;
	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_MULTIWRITE | MMC_CAP_BYTEBLOCK;

	mmc->ocr_avail = 0;
	if (caps & SDHCI_CAN_VDD_330)
		mmc->ocr_avail |= MMC_VDD_32_33|MMC_VDD_33_34;
	else if (caps & SDHCI_CAN_VDD_300)
		mmc->ocr_avail |= MMC_VDD_29_30|MMC_VDD_30_31;
	else if (caps & SDHCI_CAN_VDD_180)
		mmc->ocr_avail |= MMC_VDD_17_18|MMC_VDD_18_19;

	if ((host->max_clk > 25000000) && !(caps & SDHCI_CAN_DO_HISPD)) {
		printk(KERN_ERR "%s: Controller reports > 25 MHz base clock,"
			" but no high speed support.\n",
			host->slot_descr);
		mmc->f_max = 25000000;
	}

	if (mmc->ocr_avail == 0) {
		printk(KERN_ERR "%s: Hardware doesn't report any "
			"support voltages.\n", host->slot_descr);
		ret = -ENODEV;
		goto unmap;
	}

	spin_lock_init(&host->lock);

	/*
	 * Maximum number of segments. Hardware cannot do scatter lists.
	 */
	if (host->flags & SDHCI_USE_DMA)
		mmc->max_hw_segs = 1;
	else
		mmc->max_hw_segs = 16;
	mmc->max_phys_segs = 16;

	/*
	 * Maximum number of sectors in one transfer. Limited by DMA boundary
	 * size (512KiB), which means (512 KiB/512=) 1024 entries.
	 */
	mmc->max_sectors = 1024;

	/*
	 * Maximum segment size. Could be one segment with the maximum number
	 * of sectors.
	 */
	mmc->max_seg_size = mmc->max_sectors * 512;

	/*
	 * Init tasklets.
	 */
	tasklet_init(&host->card_tasklet,
		sdhci_tasklet_card, (unsigned long)host);
	tasklet_init(&host->finish_tasklet,
		sdhci_tasklet_finish, (unsigned long)host);

	setup_timer(&host->timer, sdhci_timeout_timer, (unsigned long)host);

	ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
		host->slot_descr, host);
	if (ret)
		goto untasklet;

	sdhci_init(host);

#ifdef CONFIG_MMC_DEBUG
	sdhci_dumpregs(host);
#endif

	mmiowb();

	mmc_add_host(mmc);

	printk(KERN_INFO "%s: SDHCI at 0x%08lx irq %d %s\n", mmc_hostname(mmc),
		host->addr, host->irq,
		(host->flags & SDHCI_USE_DMA)?"DMA":"PIO");

	return 0;

untasklet:
	tasklet_kill(&host->card_tasklet);
	tasklet_kill(&host->finish_tasklet);
unmap:
	iounmap(host->ioaddr);
release:
	pci_release_region(pdev, host->bar);
free:
	mmc_free_host(mmc);

	return ret;
}

static void sdhci_remove_slot(struct pci_dev *pdev, int slot)
{
	struct sdhci_chip *chip;
	struct mmc_host *mmc;
	struct sdhci_host *host;

	chip = pci_get_drvdata(pdev);
	host = chip->hosts[slot];
	mmc = host->mmc;

	chip->hosts[slot] = NULL;

	mmc_remove_host(mmc);

	sdhci_reset(host, SDHCI_RESET_ALL);

	free_irq(host->irq, host);

	del_timer_sync(&host->timer);

	tasklet_kill(&host->card_tasklet);
	tasklet_kill(&host->finish_tasklet);

	iounmap(host->ioaddr);

	pci_release_region(pdev, host->bar);

	mmc_free_host(mmc);
}

static int __devinit sdhci_probe(struct pci_dev *pdev,
	const struct pci_device_id *ent)
{
	int ret, i;
	u8 slots, rev;
	struct sdhci_chip *chip;

	BUG_ON(pdev == NULL);
	BUG_ON(ent == NULL);

	pci_read_config_byte(pdev, PCI_CLASS_REVISION, &rev);

	printk(KERN_INFO DRIVER_NAME
		": SDHCI controller found at %s [%04x:%04x] (rev %x)\n",
		pci_name(pdev), (int)pdev->vendor, (int)pdev->device,
		(int)rev);

	ret = pci_read_config_byte(pdev, PCI_SLOT_INFO, &slots);
	if (ret)
		return ret;

	slots = PCI_SLOT_INFO_SLOTS(slots) + 1;
	DBG("found %d slot(s)\n", slots);
	if (slots == 0)
		return -ENODEV;

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

	chip = kzalloc(sizeof(struct sdhci_chip) +
		sizeof(struct sdhci_host*) * slots, GFP_KERNEL);
	if (!chip) {
		ret = -ENOMEM;
		goto err;
	}

	chip->pdev = pdev;
	chip->quirks = ent->driver_data;

	if (debug_quirks)
		chip->quirks = debug_quirks;

	chip->num_slots = slots;
	pci_set_drvdata(pdev, chip);

	for (i = 0;i < slots;i++) {
		ret = sdhci_probe_slot(pdev, i);
		if (ret) {
			for (i--;i >= 0;i--)
				sdhci_remove_slot(pdev, i);
			goto free;
		}
	}

	return 0;

free:
	pci_set_drvdata(pdev, NULL);
	kfree(chip);

err:
	pci_disable_device(pdev);
	return ret;
}

static void __devexit sdhci_remove(struct pci_dev *pdev)
{
	int i;
	struct sdhci_chip *chip;

	chip = pci_get_drvdata(pdev);

	if (chip) {
		for (i = 0;i < chip->num_slots;i++)
			sdhci_remove_slot(pdev, i);

		pci_set_drvdata(pdev, NULL);

		kfree(chip);
	}

	pci_disable_device(pdev);
}

static struct pci_driver sdhci_driver = {
	.name = 	DRIVER_NAME,
	.id_table =	pci_ids,
	.probe = 	sdhci_probe,
	.remove =	__devexit_p(sdhci_remove),
	.suspend =	sdhci_suspend,
	.resume	=	sdhci_resume,
};

/*****************************************************************************\
 *                                                                           *
 * Driver init/exit                                                          *
 *                                                                           *
\*****************************************************************************/

static int __init sdhci_drv_init(void)
{
	printk(KERN_INFO DRIVER_NAME
		": Secure Digital Host Controller Interface driver, "
		DRIVER_VERSION "\n");
	printk(KERN_INFO DRIVER_NAME ": Copyright(c) Pierre Ossman\n");

	return pci_register_driver(&sdhci_driver);
}

static void __exit sdhci_drv_exit(void)
{
	DBG("Exiting\n");

	pci_unregister_driver(&sdhci_driver);
}

module_init(sdhci_drv_init);
module_exit(sdhci_drv_exit);

module_param(debug_nodma, uint, 0444);
module_param(debug_forcedma, uint, 0444);
module_param(debug_quirks, uint, 0444);

MODULE_AUTHOR("Pierre Ossman <[e-mail]>");
MODULE_DESCRIPTION("Secure Digital Host Controller Interface driver");
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL");

MODULE_PARM_DESC(debug_nodma, "Forcefully disable DMA transfers. (default 0)");
MODULE_PARM_DESC(debug_forcedma, "Forcefully enable DMA transfers. (default 0)");
MODULE_PARM_DESC(debug_quirks, "Force certain quirks.");