sl811-hcd.c

linux-2.6.15.6

/*
 * SL811HS HCD (Host Controller Driver) for USB.
 *
 * Copyright (C) 2004 Psion Teklogix (for NetBook PRO)
 * Copyright (C) 2004-2005 David Brownell
 *
 * Periodic scheduling is based on Roman's OHCI code
 * 	Copyright (C) 1999 Roman Weissgaerber
 *
 * The SL811HS controller handles host side USB (like the SL11H, but with
 * another register set and SOF generation) as well as peripheral side USB
 * (like the SL811S).  This driver version doesn't implement the Gadget API
 * for the peripheral role; or OTG (that'd need much external circuitry).
 *
 * For documentation, see the SL811HS spec and the "SL811HS Embedded Host"
 * document (providing significant pieces missing from that spec); plus
 * the SL811S spec if you want peripheral side info.
 */

/*
 * Status:  Passed basic stress testing, works with hubs, mice, keyboards,
 * and usb-storage.
 *
 * TODO:
 * - usb suspend/resume triggered by sl811 (with USB_SUSPEND)
 * - various issues noted in the code
 * - performance work; use both register banks; ...
 * - use urb->iso_frame_desc[] with ISO transfers
 */

#undef	VERBOSE
#undef	PACKET_TRACE

#include <linux/config.h>

#ifdef CONFIG_USB_DEBUG
#	define DEBUG
#else
#	undef DEBUG
#endif

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/timer.h>
#include <linux/list.h>
#include <linux/interrupt.h>
#include <linux/usb.h>
#include <linux/usb_sl811.h>
#include <linux/platform_device.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/byteorder.h>

#include "../core/hcd.h"
#include "sl811.h"


MODULE_DESCRIPTION("SL811HS USB Host Controller Driver");
MODULE_LICENSE("GPL");

#define DRIVER_VERSION	"19 May 2005"


#ifndef DEBUG
#	define	STUB_DEBUG_FILE
#endif

/* for now, use only one transfer register bank */
#undef	USE_B

/* this doesn't understand urb->iso_frame_desc[], but if you had a driver
 * that just queued one ISO frame per URB then iso transfers "should" work
 * using the normal urb status fields.
 */
#define	DISABLE_ISO

// #define	QUIRK2
#define	QUIRK3

static const char hcd_name[] = "sl811-hcd";

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

static void port_power(struct sl811 *sl811, int is_on)
{
	struct usb_hcd	*hcd = sl811_to_hcd(sl811);

	/* hub is inactive unless the port is powered */
	if (is_on) {
		if (sl811->port1 & (1 << USB_PORT_FEAT_POWER))
			return;

		sl811->port1 = (1 << USB_PORT_FEAT_POWER);
		sl811->irq_enable = SL11H_INTMASK_INSRMV;
		hcd->self.controller->power.power_state = PMSG_ON;
	} else {
		sl811->port1 = 0;
		sl811->irq_enable = 0;
		hcd->state = HC_STATE_HALT;
		hcd->self.controller->power.power_state = PMSG_SUSPEND;
	}
	sl811->ctrl1 = 0;
	sl811_write(sl811, SL11H_IRQ_ENABLE, 0);
	sl811_write(sl811, SL11H_IRQ_STATUS, ~0);

	if (sl811->board && sl811->board->port_power) {
		/* switch VBUS, at 500mA unless hub power budget gets set */
		DBG("power %s\n", is_on ? "on" : "off");
		sl811->board->port_power(hcd->self.controller, is_on);
	}

	/* reset as thoroughly as we can */
	if (sl811->board && sl811->board->reset)
		sl811->board->reset(hcd->self.controller);
	else {
		sl811_write(sl811, SL11H_CTLREG1, SL11H_CTL1MASK_SE0);
		mdelay(20);
	}

	sl811_write(sl811, SL11H_IRQ_ENABLE, 0);
	sl811_write(sl811, SL11H_CTLREG1, sl811->ctrl1);
	sl811_write(sl811, SL811HS_CTLREG2, SL811HS_CTL2_INIT);
	sl811_write(sl811, SL11H_IRQ_ENABLE, sl811->irq_enable);

	// if !is_on, put into lowpower mode now
}

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

/* This is a PIO-only HCD.  Queueing appends URBs to the endpoint's queue,
 * and may start I/O.  Endpoint queues are scanned during completion irq
 * handlers (one per packet: ACK, NAK, faults, etc) and urb cancellation.
 *
 * Using an external DMA engine to copy a packet at a time could work,
 * though setup/teardown costs may be too big to make it worthwhile.
 */

/* SETUP starts a new control request.  Devices are not allowed to
 * STALL or NAK these; they must cancel any pending control requests.
 */
static void setup_packet(
	struct sl811		*sl811,
	struct sl811h_ep	*ep,
	struct urb		*urb,
	u8			bank,
	u8			control
)
{
	u8			addr;
	u8			len;
	void __iomem		*data_reg;

	addr = SL811HS_PACKET_BUF(bank == 0);
	len = sizeof(struct usb_ctrlrequest);
	data_reg = sl811->data_reg;
	sl811_write_buf(sl811, addr, urb->setup_packet, len);

	/* autoincrementing */
	sl811_write(sl811, bank + SL11H_BUFADDRREG, addr);
	writeb(len, data_reg);
	writeb(SL_SETUP /* | ep->epnum */, data_reg);
	writeb(usb_pipedevice(urb->pipe), data_reg);

	/* always OUT/data0 */ ;
	sl811_write(sl811, bank + SL11H_HOSTCTLREG,
			control | SL11H_HCTLMASK_OUT);
	ep->length = 0;
	PACKET("SETUP qh%p\n", ep);
}

/* STATUS finishes control requests, often after IN or OUT data packets */
static void status_packet(
	struct sl811		*sl811,
	struct sl811h_ep	*ep,
	struct urb		*urb,
	u8			bank,
	u8			control
)
{
	int			do_out;
	void __iomem		*data_reg;

	do_out = urb->transfer_buffer_length && usb_pipein(urb->pipe);
	data_reg = sl811->data_reg;

	/* autoincrementing */
	sl811_write(sl811, bank + SL11H_BUFADDRREG, 0);
	writeb(0, data_reg);
	writeb((do_out ? SL_OUT : SL_IN) /* | ep->epnum */, data_reg);
	writeb(usb_pipedevice(urb->pipe), data_reg);

	/* always data1; sometimes IN */
	control |= SL11H_HCTLMASK_TOGGLE;
	if (do_out)
		control |= SL11H_HCTLMASK_OUT;
	sl811_write(sl811, bank + SL11H_HOSTCTLREG, control);
	ep->length = 0;
	PACKET("STATUS%s/%s qh%p\n", ep->nak_count ? "/retry" : "",
			do_out ? "out" : "in", ep);
}

/* IN packets can be used with any type of endpoint. here we just
 * start the transfer, data from the peripheral may arrive later.
 * urb->iso_frame_desc is currently ignored here...
 */
static void in_packet(
	struct sl811		*sl811,
	struct sl811h_ep	*ep,
	struct urb		*urb,
	u8			bank,
	u8			control
)
{
	u8			addr;
	u8			len;
	void __iomem		*data_reg;

	/* avoid losing data on overflow */
	len = ep->maxpacket;
	addr = SL811HS_PACKET_BUF(bank == 0);
	if (!(control & SL11H_HCTLMASK_ISOCH)
			&& usb_gettoggle(urb->dev, ep->epnum, 0))
		control |= SL11H_HCTLMASK_TOGGLE;
	data_reg = sl811->data_reg;

	/* autoincrementing */
	sl811_write(sl811, bank + SL11H_BUFADDRREG, addr);
	writeb(len, data_reg);
	writeb(SL_IN | ep->epnum, data_reg);
	writeb(usb_pipedevice(urb->pipe), data_reg);

	sl811_write(sl811, bank + SL11H_HOSTCTLREG, control);
	ep->length = min((int)len,
			urb->transfer_buffer_length - urb->actual_length);
	PACKET("IN%s/%d qh%p len%d\n", ep->nak_count ? "/retry" : "",
			!!usb_gettoggle(urb->dev, ep->epnum, 0), ep, len);
}

/* OUT packets can be used with any type of endpoint.
 * urb->iso_frame_desc is currently ignored here...
 */
static void out_packet(
	struct sl811		*sl811,
	struct sl811h_ep	*ep,
	struct urb		*urb,
	u8			bank,
	u8			control
)
{
	void			*buf;
	u8			addr;
	u8			len;
	void __iomem		*data_reg;

	buf = urb->transfer_buffer + urb->actual_length;
	prefetch(buf);

	len = min((int)ep->maxpacket,
			urb->transfer_buffer_length - urb->actual_length);

	if (!(control & SL11H_HCTLMASK_ISOCH)
			&& usb_gettoggle(urb->dev, ep->epnum, 1))
		control |= SL11H_HCTLMASK_TOGGLE;
	addr = SL811HS_PACKET_BUF(bank == 0);
	data_reg = sl811->data_reg;

	sl811_write_buf(sl811, addr, buf, len);

	/* autoincrementing */
	sl811_write(sl811, bank + SL11H_BUFADDRREG, addr);
	writeb(len, data_reg);
	writeb(SL_OUT | ep->epnum, data_reg);
	writeb(usb_pipedevice(urb->pipe), data_reg);

	sl811_write(sl811, bank + SL11H_HOSTCTLREG,
			control | SL11H_HCTLMASK_OUT);
	ep->length = len;
	PACKET("OUT%s/%d qh%p len%d\n", ep->nak_count ? "/retry" : "",
			!!usb_gettoggle(urb->dev, ep->epnum, 1), ep, len);
}

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

/* caller updates on-chip enables later */

static inline void sofirq_on(struct sl811 *sl811)
{
	if (sl811->irq_enable & SL11H_INTMASK_SOFINTR)
		return;
	VDBG("sof irq on\n");
	sl811->irq_enable |= SL11H_INTMASK_SOFINTR;
}

static inline void sofirq_off(struct sl811 *sl811)
{
	if (!(sl811->irq_enable & SL11H_INTMASK_SOFINTR))
		return;
	VDBG("sof irq off\n");
	sl811->irq_enable &= ~SL11H_INTMASK_SOFINTR;
}

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

/* pick the next endpoint for a transaction, and issue it.
 * frames start with periodic transfers (after whatever is pending
 * from the previous frame), and the rest of the time is async
 * transfers, scheduled round-robin.
 */
static struct sl811h_ep	*start(struct sl811 *sl811, u8 bank)
{
	struct sl811h_ep	*ep;
	struct urb		*urb;
	int			fclock;
	u8			control;

	/* use endpoint at schedule head */
	if (sl811->next_periodic) {
		ep = sl811->next_periodic;
		sl811->next_periodic = ep->next;
	} else {
		if (sl811->next_async)
			ep = sl811->next_async;
		else if (!list_empty(&sl811->async))
			ep = container_of(sl811->async.next,
					struct sl811h_ep, schedule);
		else {
			/* could set up the first fullspeed periodic
			 * transfer for the next frame ...
			 */
			return NULL;
		}

#ifdef USE_B
		if ((bank && sl811->active_b == ep) || sl811->active_a == ep)
			return NULL;
#endif

		if (ep->schedule.next == &sl811->async)
			sl811->next_async = NULL;
		else
			sl811->next_async = container_of(ep->schedule.next,
					struct sl811h_ep, schedule);
	}

	if (unlikely(list_empty(&ep->hep->urb_list))) {
		DBG("empty %p queue?\n", ep);
		return NULL;
	}

	urb = container_of(ep->hep->urb_list.next, struct urb, urb_list);
	control = ep->defctrl;

	/* if this frame doesn't have enough time left to transfer this
	 * packet, wait till the next frame.  too-simple algorithm...
	 */
	fclock = sl811_read(sl811, SL11H_SOFTMRREG) << 6;
	fclock -= 100;		/* setup takes not much time */
	if (urb->dev->speed == USB_SPEED_LOW) {
		if (control & SL11H_HCTLMASK_PREAMBLE) {
			/* also note erratum 1: some hubs won't work */
			fclock -= 800;
		}
		fclock -= ep->maxpacket << 8;

		/* erratum 2: AFTERSOF only works for fullspeed */
		if (fclock < 0) {
			if (ep->period)
				sl811->stat_overrun++;
			sofirq_on(sl811);
			return NULL;
		}
	} else {
		fclock -= 12000 / 19;	/* 19 64byte packets/msec */
		if (fclock < 0) {
			if (ep->period)
				sl811->stat_overrun++;
			control |= SL11H_HCTLMASK_AFTERSOF;

		/* throttle bulk/control irq noise */
		} else if (ep->nak_count)
			control |= SL11H_HCTLMASK_AFTERSOF;
	}


	switch (ep->nextpid) {
	case USB_PID_IN:
		in_packet(sl811, ep, urb, bank, control);
		break;
	case USB_PID_OUT:
		out_packet(sl811, ep, urb, bank, control);
		break;
	case USB_PID_SETUP:
		setup_packet(sl811, ep, urb, bank, control);
		break;
	case USB_PID_ACK:		/* for control status */
		status_packet(sl811, ep, urb, bank, control);
		break;
	default:
		DBG("bad ep%p pid %02x\n", ep, ep->nextpid);
		ep = NULL;
	}
	return ep;
}

#define MIN_JIFFIES	((msecs_to_jiffies(2) > 1) ? msecs_to_jiffies(2) : 2)

static inline void start_transfer(struct sl811 *sl811)
{
	if (sl811->port1 & (1 << USB_PORT_FEAT_SUSPEND))
		return;
	if (sl811->active_a == NULL) {
		sl811->active_a = start(sl811, SL811_EP_A(SL811_HOST_BUF));
		if (sl811->active_a != NULL)
			sl811->jiffies_a = jiffies + MIN_JIFFIES;
	}
#ifdef USE_B
	if (sl811->active_b == NULL) {
		sl811->active_b = start(sl811, SL811_EP_B(SL811_HOST_BUF));
		if (sl811->active_b != NULL)
			sl811->jiffies_b = jiffies + MIN_JIFFIES;
	}
#endif
}

static void finish_request(
	struct sl811		*sl811,
	struct sl811h_ep	*ep,
	struct urb		*urb,
	struct pt_regs		*regs,
	int			status
) __releases(sl811->lock) __acquires(sl811->lock)
{
	unsigned		i;

	if (usb_pipecontrol(urb->pipe))
		ep->nextpid = USB_PID_SETUP;

	spin_lock(&urb->lock);
	if (urb->status == -EINPROGRESS)
		urb->status = status;
	urb->hcpriv = NULL;
	spin_unlock(&urb->lock);

	spin_unlock(&sl811->lock);
	usb_hcd_giveback_urb(sl811_to_hcd(sl811), urb, regs);
	spin_lock(&sl811->lock);

	/* leave active endpoints in the schedule */
	if (!list_empty(&ep->hep->urb_list))
		return;

	/* async deschedule? */
	if (!list_empty(&ep->schedule)) {
		list_del_init(&ep->schedule);
		if (ep == sl811->next_async)