Initial import

1 files changed, 1946 insertions, 0 deletions

diff --git a/drivers/usb/host/imx21-hcd.c b/drivers/usb/host/imx21-hcd.c
new file mode 100644
index 000000000..f542045dc
--- /dev/null
+++ b/drivers/usb/host/imx21-hcd.c
@@ -0,0 +1,1946 @@
+/*
+ * USB Host Controller Driver for IMX21
+ *
+ * Copyright (C) 2006 Loping Dog Embedded Systems
+ * Copyright (C) 2009 Martin Fuzzey
+ * Originally written by Jay Monkman <jtm@lopingdog.com>
+ * Ported to 2.6.30, debugged and enhanced by Martin Fuzzey
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+ /*
+  * The i.MX21 USB hardware contains
+  *    * 32 transfer descriptors (called ETDs)
+  *    * 4Kb of Data memory
+  *
+  * The data memory is shared between the host and function controllers
+  * (but this driver only supports the host controller)
+  *
+  * So setting up a transfer involves:
+  *    * Allocating a ETD
+  *    * Fill in ETD with appropriate information
+  *    * Allocating data memory (and putting the offset in the ETD)
+  *    * Activate the ETD
+  *    * Get interrupt when done.
+  *
+  * An ETD is assigned to each active endpoint.
+  *
+  * Low resource (ETD and Data memory) situations are handled differently for
+  * isochronous and non insosynchronous transactions :
+  *
+  * Non ISOC transfers are queued if either ETDs or Data memory are unavailable
+  *
+  * ISOC transfers use 2 ETDs per endpoint to achieve double buffering.
+  * They allocate both ETDs and Data memory during URB submission
+  * (and fail if unavailable).
+  */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+
+#include "imx21-hcd.h"
+
+#ifdef CONFIG_DYNAMIC_DEBUG
+#define DEBUG
+#endif
+
+#ifdef DEBUG
+#define DEBUG_LOG_FRAME(imx21, etd, event) \
+	(etd)->event##_frame = readl((imx21)->regs + USBH_FRMNUB)
+#else
+#define DEBUG_LOG_FRAME(imx21, etd, event) do { } while (0)
+#endif
+
+static const char hcd_name[] = "imx21-hcd";
+
+static inline struct imx21 *hcd_to_imx21(struct usb_hcd *hcd)
+{
+	return (struct imx21 *)hcd->hcd_priv;
+}
+
+
+/* =========================================== */
+/* Hardware access helpers			*/
+/* =========================================== */
+
+static inline void set_register_bits(struct imx21 *imx21, u32 offset, u32 mask)
+{
+	void __iomem *reg = imx21->regs + offset;
+	writel(readl(reg) | mask, reg);
+}
+
+static inline void clear_register_bits(struct imx21 *imx21,
+	u32 offset, u32 mask)
+{
+	void __iomem *reg = imx21->regs + offset;
+	writel(readl(reg) & ~mask, reg);
+}
+
+static inline void clear_toggle_bit(struct imx21 *imx21, u32 offset, u32 mask)
+{
+	void __iomem *reg = imx21->regs + offset;
+
+	if (readl(reg) & mask)
+		writel(mask, reg);
+}
+
+static inline void set_toggle_bit(struct imx21 *imx21, u32 offset, u32 mask)
+{
+	void __iomem *reg = imx21->regs + offset;
+
+	if (!(readl(reg) & mask))
+		writel(mask, reg);
+}
+
+static void etd_writel(struct imx21 *imx21, int etd_num, int dword, u32 value)
+{
+	writel(value, imx21->regs + USB_ETD_DWORD(etd_num, dword));
+}
+
+static u32 etd_readl(struct imx21 *imx21, int etd_num, int dword)
+{
+	return readl(imx21->regs + USB_ETD_DWORD(etd_num, dword));
+}
+
+static inline int wrap_frame(int counter)
+{
+	return counter & 0xFFFF;
+}
+
+static inline int frame_after(int frame, int after)
+{
+	/* handle wrapping like jiffies time_afer */
+	return (s16)((s16)after - (s16)frame) < 0;
+}
+
+static int imx21_hc_get_frame(struct usb_hcd *hcd)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+
+	return wrap_frame(readl(imx21->regs + USBH_FRMNUB));
+}
+
+static inline bool unsuitable_for_dma(dma_addr_t addr)
+{
+	return (addr & 3) != 0;
+}
+
+#include "imx21-dbg.c"
+
+static void nonisoc_urb_completed_for_etd(
+	struct imx21 *imx21, struct etd_priv *etd, int status);
+static void schedule_nonisoc_etd(struct imx21 *imx21, struct urb *urb);
+static void free_dmem(struct imx21 *imx21, struct etd_priv *etd);
+
+/* =========================================== */
+/* ETD management				*/
+/* ===========================================	*/
+
+static int alloc_etd(struct imx21 *imx21)
+{
+	int i;
+	struct etd_priv *etd = imx21->etd;
+
+	for (i = 0; i < USB_NUM_ETD; i++, etd++) {
+		if (etd->alloc == 0) {
+			memset(etd, 0, sizeof(imx21->etd[0]));
+			etd->alloc = 1;
+			debug_etd_allocated(imx21);
+			return i;
+		}
+	}
+	return -1;
+}
+
+static void disactivate_etd(struct imx21 *imx21, int num)
+{
+	int etd_mask = (1 << num);
+	struct etd_priv *etd = &imx21->etd[num];
+
+	writel(etd_mask, imx21->regs + USBH_ETDENCLR);
+	clear_register_bits(imx21, USBH_ETDDONEEN, etd_mask);
+	writel(etd_mask, imx21->regs + USB_ETDDMACHANLCLR);
+	clear_toggle_bit(imx21, USBH_ETDDONESTAT, etd_mask);
+
+	etd->active_count = 0;
+
+	DEBUG_LOG_FRAME(imx21, etd, disactivated);
+}
+
+static void reset_etd(struct imx21 *imx21, int num)
+{
+	struct etd_priv *etd = imx21->etd + num;
+	int i;
+
+	disactivate_etd(imx21, num);
+
+	for (i = 0; i < 4; i++)
+		etd_writel(imx21, num, i, 0);
+	etd->urb = NULL;
+	etd->ep = NULL;
+	etd->td = NULL;
+	etd->bounce_buffer = NULL;
+}
+
+static void free_etd(struct imx21 *imx21, int num)
+{
+	if (num < 0)
+		return;
+
+	if (num >= USB_NUM_ETD) {
+		dev_err(imx21->dev, "BAD etd=%d!\n", num);
+		return;
+	}
+	if (imx21->etd[num].alloc == 0) {
+		dev_err(imx21->dev, "ETD %d already free!\n", num);
+		return;
+	}
+
+	debug_etd_freed(imx21);
+	reset_etd(imx21, num);
+	memset(&imx21->etd[num], 0, sizeof(imx21->etd[0]));
+}
+
+
+static void setup_etd_dword0(struct imx21 *imx21,
+	int etd_num, struct urb *urb,  u8 dir, u16 maxpacket)
+{
+	etd_writel(imx21, etd_num, 0,
+		((u32) usb_pipedevice(urb->pipe)) <<  DW0_ADDRESS |
+		((u32) usb_pipeendpoint(urb->pipe) << DW0_ENDPNT) |
+		((u32) dir << DW0_DIRECT) |
+		((u32) ((urb->dev->speed == USB_SPEED_LOW) ?
+			1 : 0) << DW0_SPEED) |
+		((u32) fmt_urb_to_etd[usb_pipetype(urb->pipe)] << DW0_FORMAT) |
+		((u32) maxpacket << DW0_MAXPKTSIZ));
+}
+
+/**
+ * Copy buffer to data controller data memory.
+ * We cannot use memcpy_toio() because the hardware requires 32bit writes
+ */
+static void copy_to_dmem(
+	struct imx21 *imx21, int dmem_offset, void *src, int count)
+{
+	void __iomem *dmem = imx21->regs + USBOTG_DMEM + dmem_offset;
+	u32 word = 0;
+	u8 *p = src;
+	int byte = 0;
+	int i;
+
+	for (i = 0; i < count; i++) {
+		byte = i % 4;
+		word += (*p++ << (byte * 8));
+		if (byte == 3) {
+			writel(word, dmem);
+			dmem += 4;
+			word = 0;
+		}
+	}
+
+	if (count && byte != 3)
+		writel(word, dmem);
+}
+
+static void activate_etd(struct imx21 *imx21, int etd_num, u8 dir)
+{
+	u32 etd_mask = 1 << etd_num;
+	struct etd_priv *etd = &imx21->etd[etd_num];
+
+	if (etd->dma_handle && unsuitable_for_dma(etd->dma_handle)) {
+		/* For non aligned isoc the condition below is always true */
+		if (etd->len <= etd->dmem_size) {
+			/* Fits into data memory, use PIO */
+			if (dir != TD_DIR_IN) {
+				copy_to_dmem(imx21,
+						etd->dmem_offset,
+						etd->cpu_buffer, etd->len);
+			}
+			etd->dma_handle = 0;
+
+		} else {
+			/* Too big for data memory, use bounce buffer */
+			enum dma_data_direction dmadir;
+
+			if (dir == TD_DIR_IN) {
+				dmadir = DMA_FROM_DEVICE;
+				etd->bounce_buffer = kmalloc(etd->len,
+								GFP_ATOMIC);
+			} else {
+				dmadir = DMA_TO_DEVICE;
+				etd->bounce_buffer = kmemdup(etd->cpu_buffer,
+								etd->len,
+								GFP_ATOMIC);
+			}
+			if (!etd->bounce_buffer) {
+				dev_err(imx21->dev, "failed bounce alloc\n");
+				goto err_bounce_alloc;
+			}
+
+			etd->dma_handle =
+				dma_map_single(imx21->dev,
+						etd->bounce_buffer,
+						etd->len,
+						dmadir);
+			if (dma_mapping_error(imx21->dev, etd->dma_handle)) {
+				dev_err(imx21->dev, "failed bounce map\n");
+				goto err_bounce_map;
+			}
+		}
+	}
+
+	clear_toggle_bit(imx21, USBH_ETDDONESTAT, etd_mask);
+	set_register_bits(imx21, USBH_ETDDONEEN, etd_mask);
+	clear_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);
+	clear_toggle_bit(imx21, USBH_YFILLSTAT, etd_mask);
+
+	if (etd->dma_handle) {
+		set_register_bits(imx21, USB_ETDDMACHANLCLR, etd_mask);
+		clear_toggle_bit(imx21, USBH_XBUFSTAT, etd_mask);
+		clear_toggle_bit(imx21, USBH_YBUFSTAT, etd_mask);
+		writel(etd->dma_handle, imx21->regs + USB_ETDSMSA(etd_num));
+		set_register_bits(imx21, USB_ETDDMAEN, etd_mask);
+	} else {
+		if (dir != TD_DIR_IN) {
+			/* need to set for ZLP and PIO */
+			set_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);
+			set_toggle_bit(imx21, USBH_YFILLSTAT, etd_mask);
+		}
+	}
+
+	DEBUG_LOG_FRAME(imx21, etd, activated);
+
+#ifdef DEBUG
+	if (!etd->active_count) {
+		int i;
+		etd->activated_frame = readl(imx21->regs + USBH_FRMNUB);
+		etd->disactivated_frame = -1;
+		etd->last_int_frame = -1;
+		etd->last_req_frame = -1;
+
+		for (i = 0; i < 4; i++)
+			etd->submitted_dwords[i] = etd_readl(imx21, etd_num, i);
+	}
+#endif
+
+	etd->active_count = 1;
+	writel(etd_mask, imx21->regs + USBH_ETDENSET);
+	return;
+
+err_bounce_map:
+	kfree(etd->bounce_buffer);
+
+err_bounce_alloc:
+	free_dmem(imx21, etd);
+	nonisoc_urb_completed_for_etd(imx21, etd, -ENOMEM);
+}
+
+/* ===========================================	*/
+/* Data memory management			*/
+/* ===========================================	*/
+
+static int alloc_dmem(struct imx21 *imx21, unsigned int size,
+		      struct usb_host_endpoint *ep)
+{
+	unsigned int offset = 0;
+	struct imx21_dmem_area *area;
+	struct imx21_dmem_area *tmp;
+
+	size += (~size + 1) & 0x3; /* Round to 4 byte multiple */
+
+	if (size > DMEM_SIZE) {
+		dev_err(imx21->dev, "size=%d > DMEM_SIZE(%d)\n",
+			size, DMEM_SIZE);
+		return -EINVAL;
+	}
+
+	list_for_each_entry(tmp, &imx21->dmem_list, list) {
+		if ((size + offset) < offset)
+			goto fail;
+		if ((size + offset) <= tmp->offset)
+			break;
+		offset = tmp->size + tmp->offset;
+		if ((offset + size) > DMEM_SIZE)
+			goto fail;
+	}
+
+	area = kmalloc(sizeof(struct imx21_dmem_area), GFP_ATOMIC);
+	if (area == NULL)
+		return -ENOMEM;
+
+	area->ep = ep;
+	area->offset = offset;
+	area->size = size;
+	list_add_tail(&area->list, &tmp->list);
+	debug_dmem_allocated(imx21, size);
+	return offset;
+
+fail:
+	return -ENOMEM;
+}
+
+/* Memory now available for a queued ETD - activate it */
+static void activate_queued_etd(struct imx21 *imx21,
+	struct etd_priv *etd, u32 dmem_offset)
+{
+	struct urb_priv *urb_priv = etd->urb->hcpriv;
+	int etd_num = etd - &imx21->etd[0];
+	u32 maxpacket = etd_readl(imx21, etd_num, 1) >> DW1_YBUFSRTAD;
+	u8 dir = (etd_readl(imx21, etd_num, 2) >> DW2_DIRPID) & 0x03;
+
+	dev_dbg(imx21->dev, "activating queued ETD %d now DMEM available\n",
+		etd_num);
+	etd_writel(imx21, etd_num, 1,
+	    ((dmem_offset + maxpacket) << DW1_YBUFSRTAD) | dmem_offset);
+
+	etd->dmem_offset = dmem_offset;
+	urb_priv->active = 1;
+	activate_etd(imx21, etd_num, dir);
+}
+
+static void free_dmem(struct imx21 *imx21, struct etd_priv *etd)
+{
+	struct imx21_dmem_area *area;
+	struct etd_priv *tmp;
+	int found = 0;
+	int offset;
+
+	if (!etd->dmem_size)
+		return;
+	etd->dmem_size = 0;
+
+	offset = etd->dmem_offset;
+	list_for_each_entry(area, &imx21->dmem_list, list) {
+		if (area->offset == offset) {
+			debug_dmem_freed(imx21, area->size);
+			list_del(&area->list);
+			kfree(area);
+			found = 1;
+			break;
+		}
+	}
+
+	if (!found)  {
+		dev_err(imx21->dev,
+			"Trying to free unallocated DMEM %d\n", offset);
+		return;
+	}
+
+	/* Try again to allocate memory for anything we've queued */
+	list_for_each_entry_safe(etd, tmp, &imx21->queue_for_dmem, queue) {
+		offset = alloc_dmem(imx21, etd->dmem_size, etd->ep);
+		if (offset >= 0) {
+			list_del(&etd->queue);
+			activate_queued_etd(imx21, etd, (u32)offset);
+		}
+	}
+}
+
+static void free_epdmem(struct imx21 *imx21, struct usb_host_endpoint *ep)
+{
+	struct imx21_dmem_area *area, *tmp;
+
+	list_for_each_entry_safe(area, tmp, &imx21->dmem_list, list) {
+		if (area->ep == ep) {
+			dev_err(imx21->dev,
+				"Active DMEM %d for disabled ep=%p\n",
+				area->offset, ep);
+			list_del(&area->list);
+			kfree(area);
+		}
+	}
+}
+
+
+/* ===========================================	*/
+/* End handling 				*/
+/* ===========================================	*/
+
+/* Endpoint now idle - release its ETD(s) or assign to queued request */
+static void ep_idle(struct imx21 *imx21, struct ep_priv *ep_priv)
+{
+	int i;
+
+	for (i = 0; i < NUM_ISO_ETDS; i++) {
+		int etd_num = ep_priv->etd[i];
+		struct etd_priv *etd;
+		if (etd_num < 0)
+			continue;
+
+		etd = &imx21->etd[etd_num];
+		ep_priv->etd[i] = -1;
+
+		free_dmem(imx21, etd); /* for isoc */
+
+		if (list_empty(&imx21->queue_for_etd)) {
+			free_etd(imx21, etd_num);
+			continue;
+		}
+
+		dev_dbg(imx21->dev,
+			"assigning idle etd %d for queued request\n", etd_num);
+		ep_priv = list_first_entry(&imx21->queue_for_etd,
+			struct ep_priv, queue);
+		list_del(&ep_priv->queue);
+		reset_etd(imx21, etd_num);
+		ep_priv->waiting_etd = 0;
+		ep_priv->etd[i] = etd_num;
+
+		if (list_empty(&ep_priv->ep->urb_list)) {
+			dev_err(imx21->dev, "No urb for queued ep!\n");
+			continue;
+		}
+		schedule_nonisoc_etd(imx21, list_first_entry(
+			&ep_priv->ep->urb_list, struct urb, urb_list));
+	}
+}
+
+static void urb_done(struct usb_hcd *hcd, struct urb *urb, int status)
+__releases(imx21->lock)
+__acquires(imx21->lock)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	struct ep_priv *ep_priv = urb->ep->hcpriv;
+	struct urb_priv *urb_priv = urb->hcpriv;
+
+	debug_urb_completed(imx21, urb, status);
+	dev_vdbg(imx21->dev, "urb %p done %d\n", urb, status);
+
+	kfree(urb_priv->isoc_td);
+	kfree(urb->hcpriv);
+	urb->hcpriv = NULL;
+	usb_hcd_unlink_urb_from_ep(hcd, urb);
+	spin_unlock(&imx21->lock);
+	usb_hcd_giveback_urb(hcd, urb, status);
+	spin_lock(&imx21->lock);
+	if (list_empty(&ep_priv->ep->urb_list))
+		ep_idle(imx21, ep_priv);
+}
+
+static void nonisoc_urb_completed_for_etd(
+	struct imx21 *imx21, struct etd_priv *etd, int status)
+{
+	struct usb_host_endpoint *ep = etd->ep;
+
+	urb_done(imx21->hcd, etd->urb, status);
+	etd->urb = NULL;
+
+	if (!list_empty(&ep->urb_list)) {
+		struct urb *urb = list_first_entry(
+					&ep->urb_list, struct urb, urb_list);
+
+		dev_vdbg(imx21->dev, "next URB %p\n", urb);
+		schedule_nonisoc_etd(imx21, urb);
+	}
+}
+
+
+/* ===========================================	*/
+/* ISOC Handling ... 				*/
+/* ===========================================	*/
+
+static void schedule_isoc_etds(struct usb_hcd *hcd,
+	struct usb_host_endpoint *ep)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	struct ep_priv *ep_priv = ep->hcpriv;
+	struct etd_priv *etd;
+	struct urb_priv *urb_priv;
+	struct td *td;
+	int etd_num;
+	int i;
+	int cur_frame;
+	u8 dir;
+
+	for (i = 0; i < NUM_ISO_ETDS; i++) {
+too_late:
+		if (list_empty(&ep_priv->td_list))
+			break;
+
+		etd_num = ep_priv->etd[i];
+		if (etd_num < 0)
+			break;
+
+		etd = &imx21->etd[etd_num];
+		if (etd->urb)
+			continue;
+
+		td = list_entry(ep_priv->td_list.next, struct td, list);
+		list_del(&td->list);
+		urb_priv = td->urb->hcpriv;
+
+		cur_frame = imx21_hc_get_frame(hcd);
+		if (frame_after(cur_frame, td->frame)) {
+			dev_dbg(imx21->dev, "isoc too late frame %d > %d\n",
+				cur_frame, td->frame);
+			urb_priv->isoc_status = -EXDEV;
+			td->urb->iso_frame_desc[
+				td->isoc_index].actual_length = 0;
+			td->urb->iso_frame_desc[td->isoc_index].status = -EXDEV;
+			if (--urb_priv->isoc_remaining == 0)
+				urb_done(hcd, td->urb, urb_priv->isoc_status);
+			goto too_late;
+		}
+
+		urb_priv->active = 1;
+		etd->td = td;
+		etd->ep = td->ep;
+		etd->urb = td->urb;
+		etd->len = td->len;
+		etd->dma_handle = td->dma_handle;
+		etd->cpu_buffer = td->cpu_buffer;
+
+		debug_isoc_submitted(imx21, cur_frame, td);
+
+		dir = usb_pipeout(td->urb->pipe) ? TD_DIR_OUT : TD_DIR_IN;
+		setup_etd_dword0(imx21, etd_num, td->urb, dir, etd->dmem_size);
+		etd_writel(imx21, etd_num, 1, etd->dmem_offset);
+		etd_writel(imx21, etd_num, 2,
+			(TD_NOTACCESSED << DW2_COMPCODE) |
+			((td->frame & 0xFFFF) << DW2_STARTFRM));
+		etd_writel(imx21, etd_num, 3,
+			(TD_NOTACCESSED << DW3_COMPCODE0) |
+			(td->len << DW3_PKTLEN0));
+
+		activate_etd(imx21, etd_num, dir);
+	}
+}
+
+static void isoc_etd_done(struct usb_hcd *hcd, int etd_num)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	int etd_mask = 1 << etd_num;
+	struct etd_priv *etd = imx21->etd + etd_num;
+	struct urb *urb = etd->urb;
+	struct urb_priv *urb_priv = urb->hcpriv;
+	struct td *td = etd->td;
+	struct usb_host_endpoint *ep = etd->ep;
+	int isoc_index = td->isoc_index;
+	unsigned int pipe = urb->pipe;
+	int dir_in = usb_pipein(pipe);
+	int cc;
+	int bytes_xfrd;
+
+	disactivate_etd(imx21, etd_num);
+
+	cc = (etd_readl(imx21, etd_num, 3) >> DW3_COMPCODE0) & 0xf;
+	bytes_xfrd = etd_readl(imx21, etd_num, 3) & 0x3ff;
+
+	/* Input doesn't always fill the buffer, don't generate an error
+	 * when this happens.
+	 */
+	if (dir_in && (cc == TD_DATAUNDERRUN))
+		cc = TD_CC_NOERROR;
+
+	if (cc == TD_NOTACCESSED)
+		bytes_xfrd = 0;
+
+	debug_isoc_completed(imx21,
+		imx21_hc_get_frame(hcd), td, cc, bytes_xfrd);
+	if (cc) {
+		urb_priv->isoc_status = -EXDEV;
+		dev_dbg(imx21->dev,
+			"bad iso cc=0x%X frame=%d sched frame=%d "
+			"cnt=%d len=%d urb=%p etd=%d index=%d\n",
+			cc,  imx21_hc_get_frame(hcd), td->frame,
+			bytes_xfrd, td->len, urb, etd_num, isoc_index);
+	}
+
+	if (dir_in) {
+		clear_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);
+		if (!etd->dma_handle)
+			memcpy_fromio(etd->cpu_buffer,
+				imx21->regs + USBOTG_DMEM + etd->dmem_offset,
+				bytes_xfrd);
+	}
+
+	urb->actual_length += bytes_xfrd;
+	urb->iso_frame_desc[isoc_index].actual_length = bytes_xfrd;
+	urb->iso_frame_desc[isoc_index].status = cc_to_error[cc];
+
+	etd->td = NULL;
+	etd->urb = NULL;
+	etd->ep = NULL;
+
+	if (--urb_priv->isoc_remaining == 0)
+		urb_done(hcd, urb, urb_priv->isoc_status);
+
+	schedule_isoc_etds(hcd, ep);
+}
+
+static struct ep_priv *alloc_isoc_ep(
+	struct imx21 *imx21, struct usb_host_endpoint *ep)
+{
+	struct ep_priv *ep_priv;
+	int i;
+
+	ep_priv = kzalloc(sizeof(struct ep_priv), GFP_ATOMIC);
+	if (!ep_priv)
+		return NULL;
+
+	for (i = 0; i < NUM_ISO_ETDS; i++)
+		ep_priv->etd[i] = -1;
+
+	INIT_LIST_HEAD(&ep_priv->td_list);
+	ep_priv->ep = ep;
+	ep->hcpriv = ep_priv;
+	return ep_priv;
+}
+
+static int alloc_isoc_etds(struct imx21 *imx21, struct ep_priv *ep_priv)
+{
+	int i, j;
+	int etd_num;
+
+	/* Allocate the ETDs if required */
+	for (i = 0; i < NUM_ISO_ETDS; i++) {
+		if (ep_priv->etd[i] < 0) {
+			etd_num = alloc_etd(imx21);
+			if (etd_num < 0)
+				goto alloc_etd_failed;
+
+			ep_priv->etd[i] = etd_num;
+			imx21->etd[etd_num].ep = ep_priv->ep;
+		}
+	}
+	return 0;
+
+alloc_etd_failed:
+	dev_err(imx21->dev, "isoc: Couldn't allocate etd\n");
+	for (j = 0; j < i; j++) {
+		free_etd(imx21, ep_priv->etd[j]);
+		ep_priv->etd[j] = -1;
+	}
+	return -ENOMEM;
+}
+
+static int imx21_hc_urb_enqueue_isoc(struct usb_hcd *hcd,
+				     struct usb_host_endpoint *ep,
+				     struct urb *urb, gfp_t mem_flags)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	struct urb_priv *urb_priv;
+	unsigned long flags;
+	struct ep_priv *ep_priv;
+	struct td *td = NULL;
+	int i;
+	int ret;
+	int cur_frame;
+	u16 maxpacket;
+
+	urb_priv = kzalloc(sizeof(struct urb_priv), mem_flags);
+	if (urb_priv == NULL)
+		return -ENOMEM;
+
+	urb_priv->isoc_td = kzalloc(
+		sizeof(struct td) * urb->number_of_packets, mem_flags);
+	if (urb_priv->isoc_td == NULL) {
+		ret = -ENOMEM;
+		goto alloc_td_failed;
+	}
+
+	spin_lock_irqsave(&imx21->lock, flags);
+
+	if (ep->hcpriv == NULL) {
+		ep_priv = alloc_isoc_ep(imx21, ep);
+		if (ep_priv == NULL) {
+			ret = -ENOMEM;
+			goto alloc_ep_failed;
+		}
+	} else {
+		ep_priv = ep->hcpriv;
+	}
+
+	ret = alloc_isoc_etds(imx21, ep_priv);
+	if (ret)
+		goto alloc_etd_failed;
+
+	ret = usb_hcd_link_urb_to_ep(hcd, urb);
+	if (ret)
+		goto link_failed;
+
+	urb->status = -EINPROGRESS;
+	urb->actual_length = 0;
+	urb->error_count = 0;
+	urb->hcpriv = urb_priv;
+	urb_priv->ep = ep;
+
+	/* allocate data memory for largest packets if not already done */
+	maxpacket = usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe));
+	for (i = 0; i < NUM_ISO_ETDS; i++) {
+		struct etd_priv *etd = &imx21->etd[ep_priv->etd[i]];
+
+		if (etd->dmem_size > 0 && etd->dmem_size < maxpacket) {
+			/* not sure if this can really occur.... */
+			dev_err(imx21->dev, "increasing isoc buffer %d->%d\n",
+				etd->dmem_size, maxpacket);
+			ret = -EMSGSIZE;
+			goto alloc_dmem_failed;
+		}
+
+		if (etd->dmem_size == 0) {
+			etd->dmem_offset = alloc_dmem(imx21, maxpacket, ep);
+			if (etd->dmem_offset < 0) {
+				dev_dbg(imx21->dev, "failed alloc isoc dmem\n");
+				ret = -EAGAIN;
+				goto alloc_dmem_failed;
+			}
+			etd->dmem_size = maxpacket;
+		}
+	}
+
+	/* calculate frame */
+	cur_frame = imx21_hc_get_frame(hcd);
+	i = 0;
+	if (list_empty(&ep_priv->td_list)) {
+		urb->start_frame = wrap_frame(cur_frame + 5);
+	} else {
+		urb->start_frame = wrap_frame(list_entry(ep_priv->td_list.prev,
+				struct td, list)->frame + urb->interval);
+
+		if (frame_after(cur_frame, urb->start_frame)) {
+			dev_dbg(imx21->dev,
+				"enqueue: adjusting iso start %d (cur=%d) asap=%d\n",
+				urb->start_frame, cur_frame,
+				(urb->transfer_flags & URB_ISO_ASAP) != 0);
+			i = DIV_ROUND_UP(wrap_frame(
+					cur_frame - urb->start_frame),
+					urb->interval);
+
+			/* Treat underruns as if URB_ISO_ASAP was set */
+			if ((urb->transfer_flags & URB_ISO_ASAP) ||
+					i >= urb->number_of_packets) {
+				urb->start_frame = wrap_frame(urb->start_frame
+						+ i * urb->interval);
+				i = 0;
+			}
+		}
+	}
+
+	/* set up transfers */
+	urb_priv->isoc_remaining = urb->number_of_packets - i;
+	td = urb_priv->isoc_td;
+	for (; i < urb->number_of_packets; i++, td++) {
+		unsigned int offset = urb->iso_frame_desc[i].offset;
+		td->ep = ep;
+		td->urb = urb;
+		td->len = urb->iso_frame_desc[i].length;
+		td->isoc_index = i;
+		td->frame = wrap_frame(urb->start_frame + urb->interval * i);
+		td->dma_handle = urb->transfer_dma + offset;
+		td->cpu_buffer = urb->transfer_buffer + offset;
+		list_add_tail(&td->list, &ep_priv->td_list);
+	}
+
+	dev_vdbg(imx21->dev, "setup %d packets for iso frame %d->%d\n",
+		urb->number_of_packets, urb->start_frame, td->frame);
+
+	debug_urb_submitted(imx21, urb);
+	schedule_isoc_etds(hcd, ep);
+
+	spin_unlock_irqrestore(&imx21->lock, flags);
+	return 0;
+
+alloc_dmem_failed:
+	usb_hcd_unlink_urb_from_ep(hcd, urb);
+
+link_failed:
+alloc_etd_failed:
+alloc_ep_failed:
+	spin_unlock_irqrestore(&imx21->lock, flags);
+	kfree(urb_priv->isoc_td);
+
+alloc_td_failed:
+	kfree(urb_priv);
+	return ret;
+}
+
+static void dequeue_isoc_urb(struct imx21 *imx21,
+	struct urb *urb, struct ep_priv *ep_priv)
+{
+	struct urb_priv *urb_priv = urb->hcpriv;
+	struct td *td, *tmp;
+	int i;
+
+	if (urb_priv->active) {
+		for (i = 0; i < NUM_ISO_ETDS; i++) {
+			int etd_num = ep_priv->etd[i];
+			if (etd_num != -1 && imx21->etd[etd_num].urb == urb) {
+				struct etd_priv *etd = imx21->etd + etd_num;
+
+				reset_etd(imx21, etd_num);
+				free_dmem(imx21, etd);
+			}
+		}
+	}
+
+	list_for_each_entry_safe(td, tmp, &ep_priv->td_list, list) {
+		if (td->urb == urb) {
+			dev_vdbg(imx21->dev, "removing td %p\n", td);
+			list_del(&td->list);
+		}
+	}
+}
+
+/* =========================================== */
+/* NON ISOC Handling ... 			*/
+/* =========================================== */
+
+static void schedule_nonisoc_etd(struct imx21 *imx21, struct urb *urb)
+{
+	unsigned int pipe = urb->pipe;
+	struct urb_priv *urb_priv = urb->hcpriv;
+	struct ep_priv *ep_priv = urb_priv->ep->hcpriv;
+	int state = urb_priv->state;
+	int etd_num = ep_priv->etd[0];
+	struct etd_priv *etd;
+	u32 count;
+	u16 etd_buf_size;
+	u16 maxpacket;
+	u8 dir;
+	u8 bufround;
+	u8 datatoggle;
+	u8 interval = 0;
+	u8 relpolpos = 0;
+
+	if (etd_num < 0) {
+		dev_err(imx21->dev, "No valid ETD\n");
+		return;
+	}
+	if (readl(imx21->regs + USBH_ETDENSET) & (1 << etd_num))
+		dev_err(imx21->dev, "submitting to active ETD %d\n", etd_num);
+
+	etd = &imx21->etd[etd_num];
+	maxpacket = usb_maxpacket(urb->dev, pipe, usb_pipeout(pipe));
+	if (!maxpacket)
+		maxpacket = 8;
+
+	if (usb_pipecontrol(pipe) && (state != US_CTRL_DATA)) {
+		if (state == US_CTRL_SETUP) {
+			dir = TD_DIR_SETUP;
+			if (unsuitable_for_dma(urb->setup_dma))
+				usb_hcd_unmap_urb_setup_for_dma(imx21->hcd,
+					urb);
+			etd->dma_handle = urb->setup_dma;
+			etd->cpu_buffer = urb->setup_packet;
+			bufround = 0;
+			count = 8;
+			datatoggle = TD_TOGGLE_DATA0;
+		} else {	/* US_CTRL_ACK */
+			dir = usb_pipeout(pipe) ? TD_DIR_IN : TD_DIR_OUT;
+			bufround = 0;
+			count = 0;
+			datatoggle = TD_TOGGLE_DATA1;
+		}
+	} else {
+		dir = usb_pipeout(pipe) ? TD_DIR_OUT : TD_DIR_IN;
+		bufround = (dir == TD_DIR_IN) ? 1 : 0;
+		if (unsuitable_for_dma(urb->transfer_dma))
+			usb_hcd_unmap_urb_for_dma(imx21->hcd, urb);
+
+		etd->dma_handle = urb->transfer_dma;
+		etd->cpu_buffer = urb->transfer_buffer;
+		if (usb_pipebulk(pipe) && (state == US_BULK0))
+			count = 0;
+		else
+			count = urb->transfer_buffer_length;
+
+		if (usb_pipecontrol(pipe)) {
+			datatoggle = TD_TOGGLE_DATA1;
+		} else {
+			if (usb_gettoggle(
+					urb->dev,
+					usb_pipeendpoint(urb->pipe),
+					usb_pipeout(urb->pipe)))
+				datatoggle = TD_TOGGLE_DATA1;
+			else
+				datatoggle = TD_TOGGLE_DATA0;
+		}
+	}
+
+	etd->urb = urb;
+	etd->ep = urb_priv->ep;
+	etd->len = count;
+
+	if (usb_pipeint(pipe)) {
+		interval = urb->interval;
+		relpolpos = (readl(imx21->regs + USBH_FRMNUB) + 1) & 0xff;
+	}
+
+	/* Write ETD to device memory */
+	setup_etd_dword0(imx21, etd_num, urb, dir, maxpacket);
+
+	etd_writel(imx21, etd_num, 2,
+		(u32) interval << DW2_POLINTERV |
+		((u32) relpolpos << DW2_RELPOLPOS) |
+		((u32) dir << DW2_DIRPID) |
+		((u32) bufround << DW2_BUFROUND) |
+		((u32) datatoggle << DW2_DATATOG) |
+		((u32) TD_NOTACCESSED << DW2_COMPCODE));
+
+	/* DMA will always transfer buffer size even if TOBYCNT in DWORD3
+	   is smaller. Make sure we don't overrun the buffer!
+	 */
+	if (count && count < maxpacket)
+		etd_buf_size = count;
+	else
+		etd_buf_size = maxpacket;
+
+	etd_writel(imx21, etd_num, 3,
+		((u32) (etd_buf_size - 1) << DW3_BUFSIZE) | (u32) count);
+
+	if (!count)
+		etd->dma_handle = 0;
+
+	/* allocate x and y buffer space at once */
+	etd->dmem_size = (count > maxpacket) ? maxpacket * 2 : maxpacket;
+	etd->dmem_offset = alloc_dmem(imx21, etd->dmem_size, urb_priv->ep);
+	if (etd->dmem_offset < 0) {
+		/* Setup everything we can in HW and update when we get DMEM */
+		etd_writel(imx21, etd_num, 1, (u32)maxpacket << 16);
+
+		dev_dbg(imx21->dev, "Queuing etd %d for DMEM\n", etd_num);
+		debug_urb_queued_for_dmem(imx21, urb);
+		list_add_tail(&etd->queue, &imx21->queue_for_dmem);
+		return;
+	}
+
+	etd_writel(imx21, etd_num, 1,
+		(((u32) etd->dmem_offset + (u32) maxpacket) << DW1_YBUFSRTAD) |
+		(u32) etd->dmem_offset);
+
+	urb_priv->active = 1;
+
+	/* enable the ETD to kick off transfer */
+	dev_vdbg(imx21->dev, "Activating etd %d for %d bytes %s\n",
+		etd_num, count, dir != TD_DIR_IN ? "out" : "in");
+	activate_etd(imx21, etd_num, dir);
+
+}
+
+static void nonisoc_etd_done(struct usb_hcd *hcd, int etd_num)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	struct etd_priv *etd = &imx21->etd[etd_num];
+	struct urb *urb = etd->urb;
+	u32 etd_mask = 1 << etd_num;
+	struct urb_priv *urb_priv = urb->hcpriv;
+	int dir;
+	int cc;
+	u32 bytes_xfrd;
+	int etd_done;
+
+	disactivate_etd(imx21, etd_num);
+
+	dir = (etd_readl(imx21, etd_num, 0) >> DW0_DIRECT) & 0x3;
+	cc = (etd_readl(imx21, etd_num, 2) >> DW2_COMPCODE) & 0xf;
+	bytes_xfrd = etd->len - (etd_readl(imx21, etd_num, 3) & 0x1fffff);
+
+	/* save toggle carry */
+	usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
+		      usb_pipeout(urb->pipe),
+		      (etd_readl(imx21, etd_num, 0) >> DW0_TOGCRY) & 0x1);
+
+	if (dir == TD_DIR_IN) {
+		clear_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);
+		clear_toggle_bit(imx21, USBH_YFILLSTAT, etd_mask);
+
+		if (etd->bounce_buffer) {
+			memcpy(etd->cpu_buffer, etd->bounce_buffer, bytes_xfrd);
+			dma_unmap_single(imx21->dev,
+				etd->dma_handle, etd->len, DMA_FROM_DEVICE);
+		} else if (!etd->dma_handle && bytes_xfrd) {/* PIO */
+			memcpy_fromio(etd->cpu_buffer,
+				imx21->regs + USBOTG_DMEM + etd->dmem_offset,
+				bytes_xfrd);
+		}
+	}
+
+	kfree(etd->bounce_buffer);
+	etd->bounce_buffer = NULL;
+	free_dmem(imx21, etd);
+
+	urb->error_count = 0;
+	if (!(urb->transfer_flags & URB_SHORT_NOT_OK)
+			&& (cc == TD_DATAUNDERRUN))
+		cc = TD_CC_NOERROR;
+
+	if (cc != 0)
+		dev_vdbg(imx21->dev, "cc is 0x%x\n", cc);
+
+	etd_done = (cc_to_error[cc] != 0);	/* stop if error */
+
+	switch (usb_pipetype(urb->pipe)) {
+	case PIPE_CONTROL:
+		switch (urb_priv->state) {
+		case US_CTRL_SETUP:
+			if (urb->transfer_buffer_length > 0)
+				urb_priv->state = US_CTRL_DATA;
+			else
+				urb_priv->state = US_CTRL_ACK;
+			break;
+		case US_CTRL_DATA:
+			urb->actual_length += bytes_xfrd;
+			urb_priv->state = US_CTRL_ACK;
+			break;
+		case US_CTRL_ACK:
+			etd_done = 1;
+			break;
+		default:
+			dev_err(imx21->dev,
+				"Invalid pipe state %d\n", urb_priv->state);
+			etd_done = 1;
+			break;
+		}
+		break;
+
+	case PIPE_BULK:
+		urb->actual_length += bytes_xfrd;
+		if ((urb_priv->state == US_BULK)
+		    && (urb->transfer_flags & URB_ZERO_PACKET)
+		    && urb->transfer_buffer_length > 0
+		    && ((urb->transfer_buffer_length %
+			 usb_maxpacket(urb->dev, urb->pipe,
+				       usb_pipeout(urb->pipe))) == 0)) {
+			/* need a 0-packet */
+			urb_priv->state = US_BULK0;
+		} else {
+			etd_done = 1;
+		}
+		break;
+
+	case PIPE_INTERRUPT:
+		urb->actual_length += bytes_xfrd;
+		etd_done = 1;
+		break;
+	}
+
+	if (etd_done)
+		nonisoc_urb_completed_for_etd(imx21, etd, cc_to_error[cc]);
+	else {
+		dev_vdbg(imx21->dev, "next state=%d\n", urb_priv->state);
+		schedule_nonisoc_etd(imx21, urb);
+	}
+}
+
+
+static struct ep_priv *alloc_ep(void)
+{
+	int i;
+	struct ep_priv *ep_priv;
+
+	ep_priv = kzalloc(sizeof(struct ep_priv), GFP_ATOMIC);
+	if (!ep_priv)
+		return NULL;
+
+	for (i = 0; i < NUM_ISO_ETDS; ++i)
+		ep_priv->etd[i] = -1;
+
+	return ep_priv;
+}
+
+static int imx21_hc_urb_enqueue(struct usb_hcd *hcd,
+				struct urb *urb, gfp_t mem_flags)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	struct usb_host_endpoint *ep = urb->ep;
+	struct urb_priv *urb_priv;
+	struct ep_priv *ep_priv;
+	struct etd_priv *etd;
+	int ret;
+	unsigned long flags;
+
+	dev_vdbg(imx21->dev,
+		"enqueue urb=%p ep=%p len=%d "
+		"buffer=%p dma=%pad setupBuf=%p setupDma=%pad\n",
+		urb, ep,
+		urb->transfer_buffer_length,
+		urb->transfer_buffer, &urb->transfer_dma,
+		urb->setup_packet, &urb->setup_dma);
+
+	if (usb_pipeisoc(urb->pipe))
+		return imx21_hc_urb_enqueue_isoc(hcd, ep, urb, mem_flags);
+
+	urb_priv = kzalloc(sizeof(struct urb_priv), mem_flags);
+	if (!urb_priv)
+		return -ENOMEM;
+
+	spin_lock_irqsave(&imx21->lock, flags);
+
+	ep_priv = ep->hcpriv;
+	if (ep_priv == NULL) {
+		ep_priv = alloc_ep();
+		if (!ep_priv) {
+			ret = -ENOMEM;
+			goto failed_alloc_ep;
+		}
+		ep->hcpriv = ep_priv;
+		ep_priv->ep = ep;
+	}
+
+	ret = usb_hcd_link_urb_to_ep(hcd, urb);
+	if (ret)
+		goto failed_link;
+
+	urb->status = -EINPROGRESS;
+	urb->actual_length = 0;
+	urb->error_count = 0;
+	urb->hcpriv = urb_priv;
+	urb_priv->ep = ep;
+
+	switch (usb_pipetype(urb->pipe)) {
+	case PIPE_CONTROL:
+		urb_priv->state = US_CTRL_SETUP;
+		break;
+	case PIPE_BULK:
+		urb_priv->state = US_BULK;
+		break;
+	}
+
+	debug_urb_submitted(imx21, urb);
+	if (ep_priv->etd[0] < 0) {
+		if (ep_priv->waiting_etd) {
+			dev_dbg(imx21->dev,
+				"no ETD available already queued %p\n",
+				ep_priv);
+			debug_urb_queued_for_etd(imx21, urb);
+			goto out;
+		}
+		ep_priv->etd[0] = alloc_etd(imx21);
+		if (ep_priv->etd[0] < 0) {
+			dev_dbg(imx21->dev,
+				"no ETD available queueing %p\n", ep_priv);
+			debug_urb_queued_for_etd(imx21, urb);
+			list_add_tail(&ep_priv->queue, &imx21->queue_for_etd);
+			ep_priv->waiting_etd = 1;
+			goto out;
+		}
+	}
+
+	/* Schedule if no URB already active for this endpoint */
+	etd = &imx21->etd[ep_priv->etd[0]];
+	if (etd->urb == NULL) {
+		DEBUG_LOG_FRAME(imx21, etd, last_req);
+		schedule_nonisoc_etd(imx21, urb);
+	}
+
+out:
+	spin_unlock_irqrestore(&imx21->lock, flags);
+	return 0;
+
+failed_link:
+failed_alloc_ep:
+	spin_unlock_irqrestore(&imx21->lock, flags);
+	kfree(urb_priv);
+	return ret;
+}
+
+static int imx21_hc_urb_dequeue(struct usb_hcd *hcd, struct urb *urb,
+				int status)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	unsigned long flags;
+	struct usb_host_endpoint *ep;
+	struct ep_priv *ep_priv;
+	struct urb_priv *urb_priv = urb->hcpriv;
+	int ret = -EINVAL;
+
+	dev_vdbg(imx21->dev, "dequeue urb=%p iso=%d status=%d\n",
+		urb, usb_pipeisoc(urb->pipe), status);
+
+	spin_lock_irqsave(&imx21->lock, flags);
+
+	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
+	if (ret)
+		goto fail;
+	ep = urb_priv->ep;
+	ep_priv = ep->hcpriv;
+
+	debug_urb_unlinked(imx21, urb);
+
+	if (usb_pipeisoc(urb->pipe)) {
+		dequeue_isoc_urb(imx21, urb, ep_priv);
+		schedule_isoc_etds(hcd, ep);
+	} else if (urb_priv->active) {
+		int etd_num = ep_priv->etd[0];
+		if (etd_num != -1) {
+			struct etd_priv *etd = &imx21->etd[etd_num];
+
+			disactivate_etd(imx21, etd_num);
+			free_dmem(imx21, etd);
+			etd->urb = NULL;
+			kfree(etd->bounce_buffer);
+			etd->bounce_buffer = NULL;
+		}
+	}
+
+	urb_done(hcd, urb, status);
+
+	spin_unlock_irqrestore(&imx21->lock, flags);
+	return 0;
+
+fail:
+	spin_unlock_irqrestore(&imx21->lock, flags);
+	return ret;
+}
+
+/* =========================================== */
+/* Interrupt dispatch	 			*/
+/* =========================================== */
+
+static void process_etds(struct usb_hcd *hcd, struct imx21 *imx21, int sof)
+{
+	int etd_num;
+	int enable_sof_int = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&imx21->lock, flags);
+
+	for (etd_num = 0; etd_num < USB_NUM_ETD; etd_num++) {
+		u32 etd_mask = 1 << etd_num;
+		u32 enabled = readl(imx21->regs + USBH_ETDENSET) & etd_mask;
+		u32 done = readl(imx21->regs + USBH_ETDDONESTAT) & etd_mask;
+		struct etd_priv *etd = &imx21->etd[etd_num];
+
+
+		if (done) {
+			DEBUG_LOG_FRAME(imx21, etd, last_int);
+		} else {
+/*
+ * Kludge warning!
+ *
+ * When multiple transfers are using the bus we sometimes get into a state
+ * where the transfer has completed (the CC field of the ETD is != 0x0F),
+ * the ETD has self disabled but the ETDDONESTAT flag is not set
+ * (and hence no interrupt occurs).
+ * This causes the transfer in question to hang.
+ * The kludge below checks for this condition at each SOF and processes any
+ * blocked ETDs (after an arbitrary 10 frame wait)
+ *
+ * With a single active transfer the usbtest test suite will run for days
+ * without the kludge.
+ * With other bus activity (eg mass storage) even just test1 will hang without
+ * the kludge.
+ */
+			u32 dword0;
+			int cc;
+
+			if (etd->active_count && !enabled) /* suspicious... */
+				enable_sof_int = 1;
+
+			if (!sof || enabled || !etd->active_count)
+				continue;
+
+			cc = etd_readl(imx21, etd_num, 2) >> DW2_COMPCODE;
+			if (cc == TD_NOTACCESSED)
+				continue;
+
+			if (++etd->active_count < 10)
+				continue;
+
+			dword0 = etd_readl(imx21, etd_num, 0);
+			dev_dbg(imx21->dev,
+				"unblock ETD %d dev=0x%X ep=0x%X cc=0x%02X!\n",
+				etd_num, dword0 & 0x7F,
+				(dword0 >> DW0_ENDPNT) & 0x0F,
+				cc);
+
+#ifdef DEBUG
+			dev_dbg(imx21->dev,
+				"frame: act=%d disact=%d"
+				" int=%d req=%d cur=%d\n",
+				etd->activated_frame,
+				etd->disactivated_frame,
+				etd->last_int_frame,
+				etd->last_req_frame,
+				readl(imx21->regs + USBH_FRMNUB));
+			imx21->debug_unblocks++;
+#endif
+			etd->active_count = 0;
+/* End of kludge */
+		}
+
+		if (etd->ep == NULL || etd->urb == NULL) {
+			dev_dbg(imx21->dev,
+				"Interrupt for unexpected etd %d"
+				" ep=%p urb=%p\n",
+				etd_num, etd->ep, etd->urb);
+			disactivate_etd(imx21, etd_num);
+			continue;
+		}
+
+		if (usb_pipeisoc(etd->urb->pipe))
+			isoc_etd_done(hcd, etd_num);
+		else
+			nonisoc_etd_done(hcd, etd_num);
+	}
+
+	/* only enable SOF interrupt if it may be needed for the kludge */
+	if (enable_sof_int)
+		set_register_bits(imx21, USBH_SYSIEN, USBH_SYSIEN_SOFINT);
+	else
+		clear_register_bits(imx21, USBH_SYSIEN, USBH_SYSIEN_SOFINT);
+
+
+	spin_unlock_irqrestore(&imx21->lock, flags);
+}
+
+static irqreturn_t imx21_irq(struct usb_hcd *hcd)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	u32 ints = readl(imx21->regs + USBH_SYSISR);
+
+	if (ints & USBH_SYSIEN_HERRINT)
+		dev_dbg(imx21->dev, "Scheduling error\n");
+
+	if (ints & USBH_SYSIEN_SORINT)
+		dev_dbg(imx21->dev, "Scheduling overrun\n");
+
+	if (ints & (USBH_SYSISR_DONEINT | USBH_SYSISR_SOFINT))
+		process_etds(hcd, imx21, ints & USBH_SYSISR_SOFINT);
+
+	writel(ints, imx21->regs + USBH_SYSISR);
+	return IRQ_HANDLED;
+}
+
+static void imx21_hc_endpoint_disable(struct usb_hcd *hcd,
+				      struct usb_host_endpoint *ep)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	unsigned long flags;
+	struct ep_priv *ep_priv;
+	int i;
+
+	if (ep == NULL)
+		return;
+
+	spin_lock_irqsave(&imx21->lock, flags);
+	ep_priv = ep->hcpriv;
+	dev_vdbg(imx21->dev, "disable ep=%p, ep->hcpriv=%p\n", ep, ep_priv);
+
+	if (!list_empty(&ep->urb_list))
+		dev_dbg(imx21->dev, "ep's URB list is not empty\n");
+
+	if (ep_priv != NULL) {
+		for (i = 0; i < NUM_ISO_ETDS; i++) {
+			if (ep_priv->etd[i] > -1)
+				dev_dbg(imx21->dev, "free etd %d for disable\n",
+					ep_priv->etd[i]);
+
+			free_etd(imx21, ep_priv->etd[i]);
+		}
+		kfree(ep_priv);
+		ep->hcpriv = NULL;
+	}
+
+	for (i = 0; i < USB_NUM_ETD; i++) {
+		if (imx21->etd[i].alloc && imx21->etd[i].ep == ep) {
+			dev_err(imx21->dev,
+				"Active etd %d for disabled ep=%p!\n", i, ep);
+			free_etd(imx21, i);
+		}
+	}
+	free_epdmem(imx21, ep);
+	spin_unlock_irqrestore(&imx21->lock, flags);
+}
+
+/* =========================================== */
+/* Hub handling		 			*/
+/* =========================================== */
+
+static int get_hub_descriptor(struct usb_hcd *hcd,
+			      struct usb_hub_descriptor *desc)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	desc->bDescriptorType = USB_DT_HUB; /* HUB descriptor */
+	desc->bHubContrCurrent = 0;
+
+	desc->bNbrPorts = readl(imx21->regs + USBH_ROOTHUBA)
+		& USBH_ROOTHUBA_NDNSTMPRT_MASK;
+	desc->bDescLength = 9;
+	desc->bPwrOn2PwrGood = 0;
+	desc->wHubCharacteristics = (__force __u16) cpu_to_le16(
+		HUB_CHAR_NO_LPSM |	/* No power switching */
+		HUB_CHAR_NO_OCPM);	/* No over current protection */
+
+	desc->u.hs.DeviceRemovable[0] = 1 << 1;
+	desc->u.hs.DeviceRemovable[1] = ~0;
+	return 0;
+}
+
+static int imx21_hc_hub_status_data(struct usb_hcd *hcd, char *buf)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	int ports;
+	int changed = 0;
+	int i;
+	unsigned long flags;
+
+	spin_lock_irqsave(&imx21->lock, flags);
+	ports = readl(imx21->regs + USBH_ROOTHUBA)
+		& USBH_ROOTHUBA_NDNSTMPRT_MASK;
+	if (ports > 7) {
+		ports = 7;
+		dev_err(imx21->dev, "ports %d > 7\n", ports);
+	}
+	for (i = 0; i < ports; i++) {
+		if (readl(imx21->regs + USBH_PORTSTAT(i)) &
+			(USBH_PORTSTAT_CONNECTSC |
+			USBH_PORTSTAT_PRTENBLSC |
+			USBH_PORTSTAT_PRTSTATSC |
+			USBH_PORTSTAT_OVRCURIC |
+			USBH_PORTSTAT_PRTRSTSC)) {
+
+			changed = 1;
+			buf[0] |= 1 << (i + 1);
+		}
+	}
+	spin_unlock_irqrestore(&imx21->lock, flags);
+
+	if (changed)
+		dev_info(imx21->dev, "Hub status changed\n");
+	return changed;
+}
+
+static int imx21_hc_hub_control(struct usb_hcd *hcd,
+				u16 typeReq,
+				u16 wValue, u16 wIndex, char *buf, u16 wLength)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	int rc = 0;
+	u32 status_write = 0;
+
+	switch (typeReq) {
+	case ClearHubFeature:
+		dev_dbg(imx21->dev, "ClearHubFeature\n");
+		switch (wValue) {
+		case C_HUB_OVER_CURRENT:
+			dev_dbg(imx21->dev, "    OVER_CURRENT\n");
+			break;
+		case C_HUB_LOCAL_POWER:
+			dev_dbg(imx21->dev, "    LOCAL_POWER\n");
+			break;
+		default:
+			dev_dbg(imx21->dev, "    unknown\n");
+			rc = -EINVAL;
+			break;
+		}
+		break;
+
+	case ClearPortFeature:
+		dev_dbg(imx21->dev, "ClearPortFeature\n");
+		switch (wValue) {
+		case USB_PORT_FEAT_ENABLE:
+			dev_dbg(imx21->dev, "    ENABLE\n");
+			status_write = USBH_PORTSTAT_CURCONST;
+			break;
+		case USB_PORT_FEAT_SUSPEND:
+			dev_dbg(imx21->dev, "    SUSPEND\n");
+			status_write = USBH_PORTSTAT_PRTOVRCURI;
+			break;
+		case USB_PORT_FEAT_POWER:
+			dev_dbg(imx21->dev, "    POWER\n");
+			status_write = USBH_PORTSTAT_LSDEVCON;
+			break;
+		case USB_PORT_FEAT_C_ENABLE:
+			dev_dbg(imx21->dev, "    C_ENABLE\n");
+			status_write = USBH_PORTSTAT_PRTENBLSC;
+			break;
+		case USB_PORT_FEAT_C_SUSPEND:
+			dev_dbg(imx21->dev, "    C_SUSPEND\n");
+			status_write = USBH_PORTSTAT_PRTSTATSC;
+			break;
+		case USB_PORT_FEAT_C_CONNECTION:
+			dev_dbg(imx21->dev, "    C_CONNECTION\n");
+			status_write = USBH_PORTSTAT_CONNECTSC;
+			break;
+		case USB_PORT_FEAT_C_OVER_CURRENT:
+			dev_dbg(imx21->dev, "    C_OVER_CURRENT\n");
+			status_write = USBH_PORTSTAT_OVRCURIC;
+			break;
+		case USB_PORT_FEAT_C_RESET:
+			dev_dbg(imx21->dev, "    C_RESET\n");
+			status_write = USBH_PORTSTAT_PRTRSTSC;
+			break;
+		default:
+			dev_dbg(imx21->dev, "    unknown\n");
+			rc = -EINVAL;
+			break;
+		}
+
+		break;
+
+	case GetHubDescriptor:
+		dev_dbg(imx21->dev, "GetHubDescriptor\n");
+		rc = get_hub_descriptor(hcd, (void *)buf);
+		break;
+
+	case GetHubStatus:
+		dev_dbg(imx21->dev, "  GetHubStatus\n");
+		*(__le32 *) buf = 0;
+		break;
+
+	case GetPortStatus:
+		dev_dbg(imx21->dev, "GetPortStatus: port: %d, 0x%x\n",
+		    wIndex, USBH_PORTSTAT(wIndex - 1));
+		*(__le32 *) buf = readl(imx21->regs +
+			USBH_PORTSTAT(wIndex - 1));
+		break;
+
+	case SetHubFeature:
+		dev_dbg(imx21->dev, "SetHubFeature\n");
+		switch (wValue) {
+		case C_HUB_OVER_CURRENT:
+			dev_dbg(imx21->dev, "    OVER_CURRENT\n");
+			break;
+
+		case C_HUB_LOCAL_POWER:
+			dev_dbg(imx21->dev, "    LOCAL_POWER\n");
+			break;
+		default:
+			dev_dbg(imx21->dev, "    unknown\n");
+			rc = -EINVAL;
+			break;
+		}
+
+		break;
+
+	case SetPortFeature:
+		dev_dbg(imx21->dev, "SetPortFeature\n");
+		switch (wValue) {
+		case USB_PORT_FEAT_SUSPEND:
+			dev_dbg(imx21->dev, "    SUSPEND\n");
+			status_write = USBH_PORTSTAT_PRTSUSPST;
+			break;
+		case USB_PORT_FEAT_POWER:
+			dev_dbg(imx21->dev, "    POWER\n");
+			status_write = USBH_PORTSTAT_PRTPWRST;
+			break;
+		case USB_PORT_FEAT_RESET:
+			dev_dbg(imx21->dev, "    RESET\n");
+			status_write = USBH_PORTSTAT_PRTRSTST;
+			break;
+		default:
+			dev_dbg(imx21->dev, "    unknown\n");
+			rc = -EINVAL;
+			break;
+		}
+		break;
+
+	default:
+		dev_dbg(imx21->dev, "  unknown\n");
+		rc = -EINVAL;
+		break;
+	}
+
+	if (status_write)
+		writel(status_write, imx21->regs + USBH_PORTSTAT(wIndex - 1));
+	return rc;
+}
+
+/* =========================================== */
+/* Host controller management 			*/
+/* =========================================== */
+
+static int imx21_hc_reset(struct usb_hcd *hcd)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	unsigned long timeout;
+	unsigned long flags;
+
+	spin_lock_irqsave(&imx21->lock, flags);
+
+	/* Reset the Host controller modules */
+	writel(USBOTG_RST_RSTCTRL | USBOTG_RST_RSTRH |
+		USBOTG_RST_RSTHSIE | USBOTG_RST_RSTHC,
+		imx21->regs + USBOTG_RST_CTRL);
+
+	/* Wait for reset to finish */
+	timeout = jiffies + HZ;
+	while (readl(imx21->regs + USBOTG_RST_CTRL) != 0) {
+		if (time_after(jiffies, timeout)) {
+			spin_unlock_irqrestore(&imx21->lock, flags);
+			dev_err(imx21->dev, "timeout waiting for reset\n");
+			return -ETIMEDOUT;
+		}
+		spin_unlock_irq(&imx21->lock);
+		schedule_timeout_uninterruptible(1);
+		spin_lock_irq(&imx21->lock);
+	}
+	spin_unlock_irqrestore(&imx21->lock, flags);
+	return 0;
+}
+
+static int imx21_hc_start(struct usb_hcd *hcd)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	unsigned long flags;
+	int i, j;
+	u32 hw_mode = USBOTG_HWMODE_CRECFG_HOST;
+	u32 usb_control = 0;
+
+	hw_mode |= ((imx21->pdata->host_xcvr << USBOTG_HWMODE_HOSTXCVR_SHIFT) &
+			USBOTG_HWMODE_HOSTXCVR_MASK);
+	hw_mode |= ((imx21->pdata->otg_xcvr << USBOTG_HWMODE_OTGXCVR_SHIFT) &
+			USBOTG_HWMODE_OTGXCVR_MASK);
+
+	if (imx21->pdata->host1_txenoe)
+		usb_control |= USBCTRL_HOST1_TXEN_OE;
+
+	if (!imx21->pdata->host1_xcverless)
+		usb_control |= USBCTRL_HOST1_BYP_TLL;
+
+	if (imx21->pdata->otg_ext_xcvr)
+		usb_control |= USBCTRL_OTC_RCV_RXDP;
+
+
+	spin_lock_irqsave(&imx21->lock, flags);
+
+	writel((USBOTG_CLK_CTRL_HST | USBOTG_CLK_CTRL_MAIN),
+		imx21->regs + USBOTG_CLK_CTRL);
+	writel(hw_mode, imx21->regs + USBOTG_HWMODE);
+	writel(usb_control, imx21->regs + USBCTRL);
+	writel(USB_MISCCONTROL_SKPRTRY  | USB_MISCCONTROL_ARBMODE,
+		imx21->regs + USB_MISCCONTROL);
+
+	/* Clear the ETDs */
+	for (i = 0; i < USB_NUM_ETD; i++)
+		for (j = 0; j < 4; j++)
+			etd_writel(imx21, i, j, 0);
+
+	/* Take the HC out of reset */
+	writel(USBH_HOST_CTRL_HCUSBSTE_OPERATIONAL | USBH_HOST_CTRL_CTLBLKSR_1,
+		imx21->regs + USBH_HOST_CTRL);
+
+	/* Enable ports */
+	if (imx21->pdata->enable_otg_host)
+		writel(USBH_PORTSTAT_PRTPWRST | USBH_PORTSTAT_PRTENABST,
+			imx21->regs + USBH_PORTSTAT(0));
+
+	if (imx21->pdata->enable_host1)
+		writel(USBH_PORTSTAT_PRTPWRST | USBH_PORTSTAT_PRTENABST,
+			imx21->regs + USBH_PORTSTAT(1));
+
+	if (imx21->pdata->enable_host2)
+		writel(USBH_PORTSTAT_PRTPWRST | USBH_PORTSTAT_PRTENABST,
+			imx21->regs + USBH_PORTSTAT(2));
+
+
+	hcd->state = HC_STATE_RUNNING;
+
+	/* Enable host controller interrupts */
+	set_register_bits(imx21, USBH_SYSIEN,
+		USBH_SYSIEN_HERRINT |
+		USBH_SYSIEN_DONEINT | USBH_SYSIEN_SORINT);
+	set_register_bits(imx21, USBOTG_CINT_STEN, USBOTG_HCINT);
+
+	spin_unlock_irqrestore(&imx21->lock, flags);
+
+	return 0;
+}
+
+static void imx21_hc_stop(struct usb_hcd *hcd)
+{
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	unsigned long flags;
+
+	spin_lock_irqsave(&imx21->lock, flags);
+
+	writel(0, imx21->regs + USBH_SYSIEN);
+	clear_register_bits(imx21, USBOTG_CINT_STEN, USBOTG_HCINT);
+	clear_register_bits(imx21, USBOTG_CLK_CTRL_HST | USBOTG_CLK_CTRL_MAIN,
+					USBOTG_CLK_CTRL);
+	spin_unlock_irqrestore(&imx21->lock, flags);
+}
+
+/* =========================================== */
+/* Driver glue		 			*/
+/* =========================================== */
+
+static struct hc_driver imx21_hc_driver = {
+	.description = hcd_name,
+	.product_desc = "IMX21 USB Host Controller",
+	.hcd_priv_size = sizeof(struct imx21),
+
+	.flags = HCD_USB11,
+	.irq = imx21_irq,
+
+	.reset = imx21_hc_reset,
+	.start = imx21_hc_start,
+	.stop = imx21_hc_stop,
+
+	/* I/O requests */
+	.urb_enqueue = imx21_hc_urb_enqueue,
+	.urb_dequeue = imx21_hc_urb_dequeue,
+	.endpoint_disable = imx21_hc_endpoint_disable,
+
+	/* scheduling support */
+	.get_frame_number = imx21_hc_get_frame,
+
+	/* Root hub support */
+	.hub_status_data = imx21_hc_hub_status_data,
+	.hub_control = imx21_hc_hub_control,
+
+};
+
+static struct mx21_usbh_platform_data default_pdata = {
+	.host_xcvr = MX21_USBXCVR_TXDIF_RXDIF,
+	.otg_xcvr = MX21_USBXCVR_TXDIF_RXDIF,
+	.enable_host1 = 1,
+	.enable_host2 = 1,
+	.enable_otg_host = 1,
+
+};
+
+static int imx21_remove(struct platform_device *pdev)
+{
+	struct usb_hcd *hcd = platform_get_drvdata(pdev);
+	struct imx21 *imx21 = hcd_to_imx21(hcd);
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	remove_debug_files(imx21);
+	usb_remove_hcd(hcd);
+
+	if (res != NULL) {
+		clk_disable_unprepare(imx21->clk);
+		clk_put(imx21->clk);
+		iounmap(imx21->regs);
+		release_mem_region(res->start, resource_size(res));
+	}
+
+	kfree(hcd);
+	return 0;
+}
+
+
+static int imx21_probe(struct platform_device *pdev)
+{
+	struct usb_hcd *hcd;
+	struct imx21 *imx21;
+	struct resource *res;
+	int ret;
+	int irq;
+
+	printk(KERN_INFO "%s\n", imx21_hc_driver.product_desc);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return -ENXIO;
+
+	hcd = usb_create_hcd(&imx21_hc_driver,
+		&pdev->dev, dev_name(&pdev->dev));
+	if (hcd == NULL) {
+		dev_err(&pdev->dev, "Cannot create hcd (%s)\n",
+		    dev_name(&pdev->dev));
+		return -ENOMEM;
+	}
+
+	imx21 = hcd_to_imx21(hcd);
+	imx21->hcd = hcd;
+	imx21->dev = &pdev->dev;
+	imx21->pdata = dev_get_platdata(&pdev->dev);
+	if (!imx21->pdata)
+		imx21->pdata = &default_pdata;
+
+	spin_lock_init(&imx21->lock);
+	INIT_LIST_HEAD(&imx21->dmem_list);
+	INIT_LIST_HEAD(&imx21->queue_for_etd);
+	INIT_LIST_HEAD(&imx21->queue_for_dmem);
+	create_debug_files(imx21);
+
+	res = request_mem_region(res->start, resource_size(res), hcd_name);
+	if (!res) {
+		ret = -EBUSY;
+		goto failed_request_mem;
+	}
+
+	imx21->regs = ioremap(res->start, resource_size(res));
+	if (imx21->regs == NULL) {
+		dev_err(imx21->dev, "Cannot map registers\n");
+		ret = -ENOMEM;
+		goto failed_ioremap;
+	}
+
+	/* Enable clocks source */
+	imx21->clk = clk_get(imx21->dev, NULL);
+	if (IS_ERR(imx21->clk)) {
+		dev_err(imx21->dev, "no clock found\n");
+		ret = PTR_ERR(imx21->clk);
+		goto failed_clock_get;
+	}
+
+	ret = clk_set_rate(imx21->clk, clk_round_rate(imx21->clk, 48000000));
+	if (ret)
+		goto failed_clock_set;
+	ret = clk_prepare_enable(imx21->clk);
+	if (ret)
+		goto failed_clock_enable;
+
+	dev_info(imx21->dev, "Hardware HC revision: 0x%02X\n",
+		(readl(imx21->regs + USBOTG_HWMODE) >> 16) & 0xFF);
+
+	ret = usb_add_hcd(hcd, irq, 0);
+	if (ret != 0) {
+		dev_err(imx21->dev, "usb_add_hcd() returned %d\n", ret);
+		goto failed_add_hcd;
+	}
+	device_wakeup_enable(hcd->self.controller);
+
+	return 0;
+
+failed_add_hcd:
+	clk_disable_unprepare(imx21->clk);
+failed_clock_enable:
+failed_clock_set:
+	clk_put(imx21->clk);
+failed_clock_get:
+	iounmap(imx21->regs);
+failed_ioremap:
+	release_mem_region(res->start, resource_size(res));
+failed_request_mem:
+	remove_debug_files(imx21);
+	usb_put_hcd(hcd);
+	return ret;
+}
+
+static struct platform_driver imx21_hcd_driver = {
+	.driver = {
+		   .name = hcd_name,
+		   },
+	.probe = imx21_probe,
+	.remove = imx21_remove,
+	.suspend = NULL,
+	.resume = NULL,
+};
+
+module_platform_driver(imx21_hcd_driver);
+
+MODULE_DESCRIPTION("i.MX21 USB Host controller");
+MODULE_AUTHOR("Martin Fuzzey");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:imx21-hcd");