ohci-hcd.c

linux客户机函数定义的实际例子

	if ((ohci->hcca->done_head != 0)
			&& ! (le32_to_cpup (&ohci->hcca->done_head) & 0x01)) {
		ints =  OHCI_INTR_WDH;
	} else if ((ints = (readl (&regs->intrstatus)
			& readl (&regs->intrenable))) == 0) {
		return;
	} 

	// dbg ("Interrupt: %x frame: %x", ints, le16_to_cpu (ohci->hcca->frame_no));

	if (ints & OHCI_INTR_UE) {
		ohci->disabled++;
		err ("OHCI Unrecoverable Error, %s disabled", hcd->self.bus_name);
		// e.g. due to PCI Master/Target Abort

#ifdef	DEBUG
		ohci_dump (ohci, 1);
#endif
		hc_reset (ohci);
	}
  
	if (ints & OHCI_INTR_WDH) {
		writel (OHCI_INTR_WDH, &regs->intrdisable);	
		dl_done_list (ohci, dl_reverse_done_list (ohci));
		writel (OHCI_INTR_WDH, &regs->intrenable); 
	}
  
	/* could track INTR_SO to reduce available PCI/... bandwidth */

	// FIXME:  this assumes SOF (1/ms) interrupts don't get lost...
	if (ints & OHCI_INTR_SF) { 
		unsigned int frame = le16_to_cpu (ohci->hcca->frame_no) & 1;
		writel (OHCI_INTR_SF, &regs->intrdisable);	
		if (ohci->ed_rm_list [!frame] != NULL) {
			dl_del_list (ohci, !frame);
		}
		if (ohci->ed_rm_list [frame] != NULL)
			writel (OHCI_INTR_SF, &regs->intrenable);	
	}

	writel (ints, &regs->intrstatus);
	writel (OHCI_INTR_MIE, &regs->intrenable);	
}

/*-------------------------------------------------------------------------*/

static void ohci_stop (struct usb_hcd *hcd)
{	
	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);

	dbg ("%s: stop %s controller%s",
		hcd->self.bus_name,
		hcfs2string (ohci->hc_control & OHCI_CTRL_HCFS),
		ohci->disabled ? " (disabled)" : ""
		);
#ifdef	DEBUG
	ohci_dump (ohci, 1);
#endif

	if (!ohci->disabled)
		hc_reset (ohci);
	
	ohci_mem_cleanup (ohci);

#ifdef CONFIG_PCI
	pci_free_consistent (ohci->hcd.pdev, sizeof *ohci->hcca,
		ohci->hcca, ohci->hcca_dma);
#endif
}

/*-------------------------------------------------------------------------*/

static int __devinit
ohci_start (struct usb_hcd *hcd)
{
	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
	int		ret;

#ifdef CONFIG_PCI
	if (hcd->pdev) {
		ohci->hcca = pci_alloc_consistent (hcd->pdev,
				sizeof *ohci->hcca, &ohci->hcca_dma);
		if (!ohci->hcca)
			return -ENOMEM;

		/* AMD 756, for most chips (early revs), corrupts register
		 * values on read ... so enable the vendor workaround.
		 */
		if (hcd->pdev->vendor == 0x1022
				&& hcd->pdev->device == 0x740c) {
			ohci->flags = OHCI_QUIRK_AMD756;
			info ("%s: AMD756 erratum 4 workaround",
				hcd->self.bus_name);
		}

		/* Apple's OHCI driver has a lot of bizarre workarounds
		 * for this chip.  Evidently control and bulk lists
		 * can get confused.  (B&W G3 models, and ...)
		 */
		else if (hcd->pdev->vendor == 0x1045
				&& hcd->pdev->device == 0xc861) {
			info ("%s: WARNING: OPTi workarounds unavailable",
				hcd->self.bus_name);
		}
	}
#else
#	error "where's hcca coming from?"
#endif /* CONFIG_PCI */

        memset (ohci->hcca, 0, sizeof (struct ohci_hcca));
	if ((ret = ohci_mem_init (ohci)) < 0) {
		ohci_stop (hcd);
		return ret;
	}
	ohci->regs = hcd->regs;

	if (hc_reset (ohci) < 0) {
		ohci_stop (hcd);
		return -ENODEV;
	}

	if (hc_start (ohci) < 0) {
		err ("can't start %s", ohci->hcd.self.bus_name);
		ohci_stop (hcd);
		return -EBUSY;
	}

#ifdef	DEBUG
	ohci_dump (ohci, 1);
#endif
	return 0;
}

/*-------------------------------------------------------------------------*/

#ifdef	CONFIG_PM

static int ohci_suspend (struct usb_hcd *hcd, u32 state)
{
	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
	unsigned long		flags;
	u16			cmd;

	if ((ohci->hc_control & OHCI_CTRL_HCFS) != OHCI_USB_OPER) {
		dbg ("can't suspend %s (state is %s)", hcd->self.bus_name,
			hcfs2string (ohci->hc_control & OHCI_CTRL_HCFS));
		return -EIO;
	}

	/* act as if usb suspend can always be used */
	dbg ("%s: suspend to %d", hcd->self.bus_name, state);
	ohci->sleeping = 1;

	/* First stop processing */
  	spin_lock_irqsave (&ohci->lock, flags);
	ohci->hc_control &=
		~(OHCI_CTRL_PLE|OHCI_CTRL_CLE|OHCI_CTRL_BLE|OHCI_CTRL_IE);
	writel (ohci->hc_control, &ohci->regs->control);
	writel (OHCI_INTR_SF, &ohci->regs->intrstatus);
	(void) readl (&ohci->regs->intrstatus);
  	spin_unlock_irqrestore (&ohci->lock, flags);

	/* Wait a frame or two */
	mdelay (1);
	if (!readl (&ohci->regs->intrstatus) & OHCI_INTR_SF)
		mdelay (1);
		
 #ifdef CONFIG_PMAC_PBOOK
	if (_machine == _MACH_Pmac)
		disable_irq (hcd->pdev->irq);
 	/* else, 2.4 assumes shared irqs -- don't disable */
 #endif

	/* Enable remote wakeup */
	writel (readl (&ohci->regs->intrenable) | OHCI_INTR_RD,
		&ohci->regs->intrenable);

	/* Suspend chip and let things settle down a bit */
 	ohci->hc_control = OHCI_USB_SUSPEND;
 	writel (ohci->hc_control, &ohci->regs->control);
	(void) readl (&ohci->regs->control);
	mdelay (500); /* No schedule here ! */

	switch (readl (&ohci->regs->control) & OHCI_CTRL_HCFS) {
		case OHCI_USB_RESET:
			dbg ("%s suspend->reset ?", hcd->self.bus_name);
			break;
		case OHCI_USB_RESUME:
			dbg ("%s suspend->resume ?", hcd->self.bus_name);
			break;
		case OHCI_USB_OPER:
			dbg ("%s suspend->operational ?", hcd->self.bus_name);
			break;
		case OHCI_USB_SUSPEND:
			dbg ("%s suspended", hcd->self.bus_name);
			break;
	}

	/* In some rare situations, Apple's OHCI have happily trashed
	 * memory during sleep. We disable its bus master bit during
	 * suspend
	 */
	pci_read_config_word (hcd->pdev, PCI_COMMAND, &cmd);
	cmd &= ~PCI_COMMAND_MASTER;
	pci_write_config_word (hcd->pdev, PCI_COMMAND, cmd);
#ifdef CONFIG_PMAC_PBOOK
	{
	   	struct device_node	*of_node;
 
		/* Disable USB PAD & cell clock */
		of_node = pci_device_to_OF_node (hcd->pdev);
		if (of_node)
			pmac_call_feature(PMAC_FTR_USB_ENABLE, of_node, 0, 0);
	}
#endif
	return 0;
}


// FIXME:  this restart logic should be generic,
// and handle full hcd state cleanup

/* controller died; cleanup debris, then restart */
/* must not be called from interrupt context */

static int hc_restart (struct ohci_hcd *ohci)
{
	int temp;
	int i;

	ohci->disabled = 1;
	ohci->sleeping = 0;
	if (ohci->hcd.self.root_hub)
		usb_disconnect (&ohci->hcd.self.root_hub);
	
	/* empty the interrupt branches */
	for (i = 0; i < NUM_INTS; i++) ohci->ohci_int_load [i] = 0;
	for (i = 0; i < NUM_INTS; i++) ohci->hcca->int_table [i] = 0;
	
	/* no EDs to remove */
	ohci->ed_rm_list [0] = NULL;
	ohci->ed_rm_list [1] = NULL;

	/* empty control and bulk lists */	 
	ohci->ed_isotail     = NULL;
	ohci->ed_controltail = NULL;
	ohci->ed_bulktail    = NULL;

	if ((temp = hc_reset (ohci)) < 0 || (temp = hc_start (ohci)) < 0) {
		err ("can't restart %s, %d", ohci->hcd.self.bus_name, temp);
		return temp;
	} else
		dbg ("restart %s completed", ohci->hcd.self.bus_name);
	return 0;
}

static int ohci_resume (struct usb_hcd *hcd)
{
	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
	int			temp;
	int			retval = 0;
	unsigned long		flags;

#ifdef CONFIG_PMAC_PBOOK
	{
		struct device_node *of_node;

		/* Re-enable USB PAD & cell clock */
		of_node = pci_device_to_OF_node (hcd->pdev);
		if (of_node)
			pmac_call_feature (PMAC_FTR_USB_ENABLE, of_node, 0, 1);
	}
#endif
	/* did we suspend, or were we powered off? */
	ohci->hc_control = readl (&ohci->regs->control);
	temp = ohci->hc_control & OHCI_CTRL_HCFS;

#ifdef DEBUG
	/* the registers may look crazy here */
	ohci_dump_status (ohci);
#endif

	/* Re-enable bus mastering */
	pci_set_master (ohci->hcd.pdev);
	
	switch (temp) {

	case OHCI_USB_RESET:	// lost power
		info ("USB restart: %s", hcd->self.bus_name);
		retval = hc_restart (ohci);
		break;

	case OHCI_USB_SUSPEND:	// host wakeup
	case OHCI_USB_RESUME:	// remote wakeup
		info ("USB continue: %s from %s wakeup", hcd->self.bus_name,
			 (temp == OHCI_USB_SUSPEND)
				? "host" : "remote");
		ohci->hc_control = OHCI_USB_RESUME;
		writel (ohci->hc_control, &ohci->regs->control);
		(void) readl (&ohci->regs->control);
		mdelay (20); /* no schedule here ! */
		/* Some controllers (lucent) need a longer delay here */
		mdelay (15);

		temp = readl (&ohci->regs->control);
		temp = ohci->hc_control & OHCI_CTRL_HCFS;
		if (temp != OHCI_USB_RESUME) {
			err ("controller %s won't resume", hcd->self.bus_name);
			ohci->disabled = 1;
			retval = -EIO;
			break;
		}

		/* Some chips likes being resumed first */
		writel (OHCI_USB_OPER, &ohci->regs->control);
		(void) readl (&ohci->regs->control);
		mdelay (3);

		/* Then re-enable operations */
		spin_lock_irqsave (&ohci->lock, flags);
		ohci->disabled = 0;
		ohci->sleeping = 0;
		ohci->hc_control = OHCI_CONTROL_INIT | OHCI_USB_OPER;
		if (!ohci->ed_rm_list [0] && !ohci->ed_rm_list [1]) {
			if (ohci->ed_controltail)
				ohci->hc_control |= OHCI_CTRL_CLE;
			if (ohci->ed_bulktail)
				ohci->hc_control |= OHCI_CTRL_BLE;
		}
		hcd->state = USB_STATE_READY;
		writel (ohci->hc_control, &ohci->regs->control);

		/* trigger a start-frame interrupt (why?) */
		writel (OHCI_INTR_SF, &ohci->regs->intrstatus);
		writel (OHCI_INTR_SF, &ohci->regs->intrenable);

		/* Check for a pending done list */
		writel (OHCI_INTR_WDH, &ohci->regs->intrdisable);	
		(void) readl (&ohci->regs->intrdisable);
		spin_unlock_irqrestore (&ohci->lock, flags);

 #ifdef CONFIG_PMAC_PBOOK
		if (_machine == _MACH_Pmac)
			enable_irq (hcd->pdev->irq);
 #endif
		if (ohci->hcca->done_head)
			dl_done_list (ohci, dl_reverse_done_list (ohci));
		writel (OHCI_INTR_WDH, &ohci->regs->intrenable); 

		/* assume there are TDs on the bulk and control lists */
		writel (OHCI_BLF | OHCI_CLF, &ohci->regs->cmdstatus);

// ohci_dump_status (ohci);
dbg ("sleeping = %d, disabled = %d", ohci->sleeping, ohci->disabled);
		break;

	default:
		warn ("odd PCI resume for %s", hcd->self.bus_name);
	}
	return retval;
}

#endif	/* CONFIG_PM */


/*-------------------------------------------------------------------------*/

static const char	hcd_name [] = "ohci-hcd";

static const struct hc_driver ohci_driver = {
	description:		hcd_name,

	/*
	 * generic hardware linkage
	 */
	irq:			ohci_irq,
	flags:			HCD_MEMORY | HCD_USB11,

	/*
	 * basic lifecycle operations
	 */
	start:			ohci_start,
#ifdef	CONFIG_PM
	suspend:		ohci_suspend,
	resume:			ohci_resume,
#endif
	stop:			ohci_stop,

	/*
	 * memory lifecycle (except per-request)
	 */
	hcd_alloc:		ohci_hcd_alloc,
	hcd_free:		ohci_hcd_free,

	/*
	 * managing i/o requests and associated device resources
	 */
	urb_enqueue:		ohci_urb_enqueue,
	urb_dequeue:		ohci_urb_dequeue,
	free_config:		ohci_free_config,

	/*
	 * scheduling support
	 */
	get_frame_number:	ohci_get_frame,

	/*
	 * root hub support
	 */
	hub_status_data:	ohci_hub_status_data,
	hub_control:		ohci_hub_control,
};

#define DRIVER_INFO DRIVER_VERSION " " DRIVER_DESC

MODULE_AUTHOR (DRIVER_AUTHOR);
MODULE_DESCRIPTION (DRIVER_INFO);
MODULE_LICENSE ("GPL");

/*-------------------------------------------------------------------------*/

#ifdef CONFIG_PCI

/* There do exist non-PCI implementations of OHCI ...
 * Examples include the SA-1111 (ARM) and some MIPS
 * and related hardware.
 */

static const struct pci_device_id __devinitdata pci_ids [] = { {

	/* handle any USB OHCI controller */
	class:		(PCI_CLASS_SERIAL_USB << 8) | 0x10,
	class_mask:	~0,
	driver_data:	(unsigned long) &ohci_driver,

	/* no matter who makes it */
	vendor:		PCI_ANY_ID,
	device:		PCI_ANY_ID,
	subvendor:	PCI_ANY_ID,
	subdevice:	PCI_ANY_ID,

	}, { /* end: all zeroes */ }
};
MODULE_DEVICE_TABLE (pci, pci_ids);

/* pci driver glue; this is a "new style" PCI driver module */
static struct pci_driver ohci_pci_driver = {
	name:		(char *) hcd_name,
	id_table:	pci_ids,

	probe:		usb_hcd_pci_probe,
	remove:		usb_hcd_pci_remove,

#ifdef	CONFIG_PM
	suspend:	usb_hcd_pci_suspend,
	resume:		usb_hcd_pci_resume,
#endif
};

 
static int __init ohci_hcd_init (void) 
{
	dbg (DRIVER_INFO);
	dbg ("block sizes: ed %d td %d",
		sizeof (struct ed), sizeof (struct td));
	return pci_module_init (&ohci_pci_driver);
}
module_init (ohci_hcd_init);

/*-------------------------------------------------------------------------*/

static void __exit ohci_hcd_cleanup (void) 
{	
	pci_unregister_driver (&ohci_pci_driver);
}
module_exit (ohci_hcd_cleanup);

#endif /* CONFIG_PCI */