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path: root/drivers/usb/gadget/udc/gr_udc.c
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Diffstat (limited to 'drivers/usb/gadget/udc/gr_udc.c')
-rw-r--r--drivers/usb/gadget/udc/gr_udc.c2235
1 files changed, 2235 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc/gr_udc.c b/drivers/usb/gadget/udc/gr_udc.c
new file mode 100644
index 000000000000..5d93f2b1e394
--- /dev/null
+++ b/drivers/usb/gadget/udc/gr_udc.c
@@ -0,0 +1,2235 @@
+/*
+ * USB Peripheral Controller driver for Aeroflex Gaisler GRUSBDC.
+ *
+ * 2013 (c) Aeroflex Gaisler AB
+ *
+ * This driver supports GRUSBDC USB Device Controller cores available in the
+ * GRLIB VHDL IP core library.
+ *
+ * Full documentation of the GRUSBDC core can be found here:
+ * http://www.gaisler.com/products/grlib/grip.pdf
+ *
+ * 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.
+ *
+ * Contributors:
+ * - Andreas Larsson <andreas@gaisler.com>
+ * - Marko Isomaki
+ */
+
+/*
+ * A GRUSBDC core can have up to 16 IN endpoints and 16 OUT endpoints each
+ * individually configurable to any of the four USB transfer types. This driver
+ * only supports cores in DMA mode.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+#include <asm/byteorder.h>
+
+#include "gr_udc.h"
+
+#define DRIVER_NAME "gr_udc"
+#define DRIVER_DESC "Aeroflex Gaisler GRUSBDC USB Peripheral Controller"
+
+static const char driver_name[] = DRIVER_NAME;
+static const char driver_desc[] = DRIVER_DESC;
+
+#define gr_read32(x) (ioread32be((x)))
+#define gr_write32(x, v) (iowrite32be((v), (x)))
+
+/* USB speed and corresponding string calculated from status register value */
+#define GR_SPEED(status) \
+ ((status & GR_STATUS_SP) ? USB_SPEED_FULL : USB_SPEED_HIGH)
+#define GR_SPEED_STR(status) usb_speed_string(GR_SPEED(status))
+
+/* Size of hardware buffer calculated from epctrl register value */
+#define GR_BUFFER_SIZE(epctrl) \
+ ((((epctrl) & GR_EPCTRL_BUFSZ_MASK) >> GR_EPCTRL_BUFSZ_POS) * \
+ GR_EPCTRL_BUFSZ_SCALER)
+
+/* ---------------------------------------------------------------------- */
+/* Debug printout functionality */
+
+static const char * const gr_modestring[] = {"control", "iso", "bulk", "int"};
+
+static const char *gr_ep0state_string(enum gr_ep0state state)
+{
+ static const char *const names[] = {
+ [GR_EP0_DISCONNECT] = "disconnect",
+ [GR_EP0_SETUP] = "setup",
+ [GR_EP0_IDATA] = "idata",
+ [GR_EP0_ODATA] = "odata",
+ [GR_EP0_ISTATUS] = "istatus",
+ [GR_EP0_OSTATUS] = "ostatus",
+ [GR_EP0_STALL] = "stall",
+ [GR_EP0_SUSPEND] = "suspend",
+ };
+
+ if (state < 0 || state >= ARRAY_SIZE(names))
+ return "UNKNOWN";
+
+ return names[state];
+}
+
+#ifdef VERBOSE_DEBUG
+
+static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
+ struct gr_request *req)
+{
+ int buflen = ep->is_in ? req->req.length : req->req.actual;
+ int rowlen = 32;
+ int plen = min(rowlen, buflen);
+
+ dev_dbg(ep->dev->dev, "%s: 0x%p, %d bytes data%s:\n", str, req, buflen,
+ (buflen > plen ? " (truncated)" : ""));
+ print_hex_dump_debug(" ", DUMP_PREFIX_NONE,
+ rowlen, 4, req->req.buf, plen, false);
+}
+
+static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
+ u16 value, u16 index, u16 length)
+{
+ dev_vdbg(dev->dev, "REQ: %02x.%02x v%04x i%04x l%04x\n",
+ type, request, value, index, length);
+}
+#else /* !VERBOSE_DEBUG */
+
+static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
+ struct gr_request *req) {}
+
+static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
+ u16 value, u16 index, u16 length) {}
+
+#endif /* VERBOSE_DEBUG */
+
+/* ---------------------------------------------------------------------- */
+/* Debugfs functionality */
+
+#ifdef CONFIG_USB_GADGET_DEBUG_FS
+
+static void gr_seq_ep_show(struct seq_file *seq, struct gr_ep *ep)
+{
+ u32 epctrl = gr_read32(&ep->regs->epctrl);
+ u32 epstat = gr_read32(&ep->regs->epstat);
+ int mode = (epctrl & GR_EPCTRL_TT_MASK) >> GR_EPCTRL_TT_POS;
+ struct gr_request *req;
+
+ seq_printf(seq, "%s:\n", ep->ep.name);
+ seq_printf(seq, " mode = %s\n", gr_modestring[mode]);
+ seq_printf(seq, " halted: %d\n", !!(epctrl & GR_EPCTRL_EH));
+ seq_printf(seq, " disabled: %d\n", !!(epctrl & GR_EPCTRL_ED));
+ seq_printf(seq, " valid: %d\n", !!(epctrl & GR_EPCTRL_EV));
+ seq_printf(seq, " dma_start = %d\n", ep->dma_start);
+ seq_printf(seq, " stopped = %d\n", ep->stopped);
+ seq_printf(seq, " wedged = %d\n", ep->wedged);
+ seq_printf(seq, " callback = %d\n", ep->callback);
+ seq_printf(seq, " maxpacket = %d\n", ep->ep.maxpacket);
+ seq_printf(seq, " maxpacket_limit = %d\n", ep->ep.maxpacket_limit);
+ seq_printf(seq, " bytes_per_buffer = %d\n", ep->bytes_per_buffer);
+ if (mode == 1 || mode == 3)
+ seq_printf(seq, " nt = %d\n",
+ (epctrl & GR_EPCTRL_NT_MASK) >> GR_EPCTRL_NT_POS);
+
+ seq_printf(seq, " Buffer 0: %s %s%d\n",
+ epstat & GR_EPSTAT_B0 ? "valid" : "invalid",
+ epstat & GR_EPSTAT_BS ? " " : "selected ",
+ (epstat & GR_EPSTAT_B0CNT_MASK) >> GR_EPSTAT_B0CNT_POS);
+ seq_printf(seq, " Buffer 1: %s %s%d\n",
+ epstat & GR_EPSTAT_B1 ? "valid" : "invalid",
+ epstat & GR_EPSTAT_BS ? "selected " : " ",
+ (epstat & GR_EPSTAT_B1CNT_MASK) >> GR_EPSTAT_B1CNT_POS);
+
+ if (list_empty(&ep->queue)) {
+ seq_puts(seq, " Queue: empty\n\n");
+ return;
+ }
+
+ seq_puts(seq, " Queue:\n");
+ list_for_each_entry(req, &ep->queue, queue) {
+ struct gr_dma_desc *desc;
+ struct gr_dma_desc *next;
+
+ seq_printf(seq, " 0x%p: 0x%p %d %d\n", req,
+ &req->req.buf, req->req.actual, req->req.length);
+
+ next = req->first_desc;
+ do {
+ desc = next;
+ next = desc->next_desc;
+ seq_printf(seq, " %c 0x%p (0x%08x): 0x%05x 0x%08x\n",
+ desc == req->curr_desc ? 'c' : ' ',
+ desc, desc->paddr, desc->ctrl, desc->data);
+ } while (desc != req->last_desc);
+ }
+ seq_puts(seq, "\n");
+}
+
+
+static int gr_seq_show(struct seq_file *seq, void *v)
+{
+ struct gr_udc *dev = seq->private;
+ u32 control = gr_read32(&dev->regs->control);
+ u32 status = gr_read32(&dev->regs->status);
+ struct gr_ep *ep;
+
+ seq_printf(seq, "usb state = %s\n",
+ usb_state_string(dev->gadget.state));
+ seq_printf(seq, "address = %d\n",
+ (control & GR_CONTROL_UA_MASK) >> GR_CONTROL_UA_POS);
+ seq_printf(seq, "speed = %s\n", GR_SPEED_STR(status));
+ seq_printf(seq, "ep0state = %s\n", gr_ep0state_string(dev->ep0state));
+ seq_printf(seq, "irq_enabled = %d\n", dev->irq_enabled);
+ seq_printf(seq, "remote_wakeup = %d\n", dev->remote_wakeup);
+ seq_printf(seq, "test_mode = %d\n", dev->test_mode);
+ seq_puts(seq, "\n");
+
+ list_for_each_entry(ep, &dev->ep_list, ep_list)
+ gr_seq_ep_show(seq, ep);
+
+ return 0;
+}
+
+static int gr_dfs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, gr_seq_show, inode->i_private);
+}
+
+static const struct file_operations gr_dfs_fops = {
+ .owner = THIS_MODULE,
+ .open = gr_dfs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void gr_dfs_create(struct gr_udc *dev)
+{
+ const char *name = "gr_udc_state";
+
+ dev->dfs_root = debugfs_create_dir(dev_name(dev->dev), NULL);
+ dev->dfs_state = debugfs_create_file(name, 0444, dev->dfs_root, dev,
+ &gr_dfs_fops);
+}
+
+static void gr_dfs_delete(struct gr_udc *dev)
+{
+ /* Handles NULL and ERR pointers internally */
+ debugfs_remove(dev->dfs_state);
+ debugfs_remove(dev->dfs_root);
+}
+
+#else /* !CONFIG_USB_GADGET_DEBUG_FS */
+
+static void gr_dfs_create(struct gr_udc *dev) {}
+static void gr_dfs_delete(struct gr_udc *dev) {}
+
+#endif /* CONFIG_USB_GADGET_DEBUG_FS */
+
+/* ---------------------------------------------------------------------- */
+/* DMA and request handling */
+
+/* Allocates a new struct gr_dma_desc, sets paddr and zeroes the rest */
+static struct gr_dma_desc *gr_alloc_dma_desc(struct gr_ep *ep, gfp_t gfp_flags)
+{
+ dma_addr_t paddr;
+ struct gr_dma_desc *dma_desc;
+
+ dma_desc = dma_pool_alloc(ep->dev->desc_pool, gfp_flags, &paddr);
+ if (!dma_desc) {
+ dev_err(ep->dev->dev, "Could not allocate from DMA pool\n");
+ return NULL;
+ }
+
+ memset(dma_desc, 0, sizeof(*dma_desc));
+ dma_desc->paddr = paddr;
+
+ return dma_desc;
+}
+
+static inline void gr_free_dma_desc(struct gr_udc *dev,
+ struct gr_dma_desc *desc)
+{
+ dma_pool_free(dev->desc_pool, desc, (dma_addr_t)desc->paddr);
+}
+
+/* Frees the chain of struct gr_dma_desc for the given request */
+static void gr_free_dma_desc_chain(struct gr_udc *dev, struct gr_request *req)
+{
+ struct gr_dma_desc *desc;
+ struct gr_dma_desc *next;
+
+ next = req->first_desc;
+ if (!next)
+ return;
+
+ do {
+ desc = next;
+ next = desc->next_desc;
+ gr_free_dma_desc(dev, desc);
+ } while (desc != req->last_desc);
+
+ req->first_desc = NULL;
+ req->curr_desc = NULL;
+ req->last_desc = NULL;
+}
+
+static void gr_ep0_setup(struct gr_udc *dev, struct gr_request *req);
+
+/*
+ * Frees allocated resources and calls the appropriate completion function/setup
+ * package handler for a finished request.
+ *
+ * Must be called with dev->lock held and irqs disabled.
+ */
+static void gr_finish_request(struct gr_ep *ep, struct gr_request *req,
+ int status)
+ __releases(&dev->lock)
+ __acquires(&dev->lock)
+{
+ struct gr_udc *dev;
+
+ list_del_init(&req->queue);
+
+ if (likely(req->req.status == -EINPROGRESS))
+ req->req.status = status;
+ else
+ status = req->req.status;
+
+ dev = ep->dev;
+ usb_gadget_unmap_request(&dev->gadget, &req->req, ep->is_in);
+ gr_free_dma_desc_chain(dev, req);
+
+ if (ep->is_in) /* For OUT, actual gets updated bit by bit */
+ req->req.actual = req->req.length;
+
+ if (!status) {
+ if (ep->is_in)
+ gr_dbgprint_request("SENT", ep, req);
+ else
+ gr_dbgprint_request("RECV", ep, req);
+ }
+
+ /* Prevent changes to ep->queue during callback */
+ ep->callback = 1;
+ if (req == dev->ep0reqo && !status) {
+ if (req->setup)
+ gr_ep0_setup(dev, req);
+ else
+ dev_err(dev->dev,
+ "Unexpected non setup packet on ep0in\n");
+ } else if (req->req.complete) {
+ spin_unlock(&dev->lock);
+
+ req->req.complete(&ep->ep, &req->req);
+
+ spin_lock(&dev->lock);
+ }
+ ep->callback = 0;
+}
+
+static struct usb_request *gr_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
+{
+ struct gr_request *req;
+
+ req = kzalloc(sizeof(*req), gfp_flags);
+ if (!req)
+ return NULL;
+
+ INIT_LIST_HEAD(&req->queue);
+
+ return &req->req;
+}
+
+/*
+ * Starts DMA for endpoint ep if there are requests in the queue.
+ *
+ * Must be called with dev->lock held and with !ep->stopped.
+ */
+static void gr_start_dma(struct gr_ep *ep)
+{
+ struct gr_request *req;
+ u32 dmactrl;
+
+ if (list_empty(&ep->queue)) {
+ ep->dma_start = 0;
+ return;
+ }
+
+ req = list_first_entry(&ep->queue, struct gr_request, queue);
+
+ /* A descriptor should already have been allocated */
+ BUG_ON(!req->curr_desc);
+
+ wmb(); /* Make sure all is settled before handing it over to DMA */
+
+ /* Set the descriptor pointer in the hardware */
+ gr_write32(&ep->regs->dmaaddr, req->curr_desc->paddr);
+
+ /* Announce available descriptors */
+ dmactrl = gr_read32(&ep->regs->dmactrl);
+ gr_write32(&ep->regs->dmactrl, dmactrl | GR_DMACTRL_DA);
+
+ ep->dma_start = 1;
+}
+
+/*
+ * Finishes the first request in the ep's queue and, if available, starts the
+ * next request in queue.
+ *
+ * Must be called with dev->lock held, irqs disabled and with !ep->stopped.
+ */
+static void gr_dma_advance(struct gr_ep *ep, int status)
+{
+ struct gr_request *req;
+
+ req = list_first_entry(&ep->queue, struct gr_request, queue);
+ gr_finish_request(ep, req, status);
+ gr_start_dma(ep); /* Regardless of ep->dma_start */
+}
+
+/*
+ * Abort DMA for an endpoint. Sets the abort DMA bit which causes an ongoing DMA
+ * transfer to be canceled and clears GR_DMACTRL_DA.
+ *
+ * Must be called with dev->lock held.
+ */
+static void gr_abort_dma(struct gr_ep *ep)
+{
+ u32 dmactrl;
+
+ dmactrl = gr_read32(&ep->regs->dmactrl);
+ gr_write32(&ep->regs->dmactrl, dmactrl | GR_DMACTRL_AD);
+}
+
+/*
+ * Allocates and sets up a struct gr_dma_desc and putting it on the descriptor
+ * chain.
+ *
+ * Size is not used for OUT endpoints. Hardware can not be instructed to handle
+ * smaller buffer than MAXPL in the OUT direction.
+ */
+static int gr_add_dma_desc(struct gr_ep *ep, struct gr_request *req,
+ dma_addr_t data, unsigned size, gfp_t gfp_flags)
+{
+ struct gr_dma_desc *desc;
+
+ desc = gr_alloc_dma_desc(ep, gfp_flags);
+ if (!desc)
+ return -ENOMEM;
+
+ desc->data = data;
+ if (ep->is_in)
+ desc->ctrl =
+ (GR_DESC_IN_CTRL_LEN_MASK & size) | GR_DESC_IN_CTRL_EN;
+ else
+ desc->ctrl = GR_DESC_OUT_CTRL_IE;
+
+ if (!req->first_desc) {
+ req->first_desc = desc;
+ req->curr_desc = desc;
+ } else {
+ req->last_desc->next_desc = desc;
+ req->last_desc->next = desc->paddr;
+ req->last_desc->ctrl |= GR_DESC_OUT_CTRL_NX;
+ }
+ req->last_desc = desc;
+
+ return 0;
+}
+
+/*
+ * Sets up a chain of struct gr_dma_descriptors pointing to buffers that
+ * together covers req->req.length bytes of the buffer at DMA address
+ * req->req.dma for the OUT direction.
+ *
+ * The first descriptor in the chain is enabled, the rest disabled. The
+ * interrupt handler will later enable them one by one when needed so we can
+ * find out when the transfer is finished. For OUT endpoints, all descriptors
+ * therefore generate interrutps.
+ */
+static int gr_setup_out_desc_list(struct gr_ep *ep, struct gr_request *req,
+ gfp_t gfp_flags)
+{
+ u16 bytes_left; /* Bytes left to provide descriptors for */
+ u16 bytes_used; /* Bytes accommodated for */
+ int ret = 0;
+
+ req->first_desc = NULL; /* Signals that no allocation is done yet */
+ bytes_left = req->req.length;
+ bytes_used = 0;
+ while (bytes_left > 0) {
+ dma_addr_t start = req->req.dma + bytes_used;
+ u16 size = min(bytes_left, ep->bytes_per_buffer);
+
+ /* Should not happen however - gr_queue stops such lengths */
+ if (size < ep->bytes_per_buffer)
+ dev_warn(ep->dev->dev,
+ "Buffer overrun risk: %u < %u bytes/buffer\n",
+ size, ep->bytes_per_buffer);
+
+ ret = gr_add_dma_desc(ep, req, start, size, gfp_flags);
+ if (ret)
+ goto alloc_err;
+
+ bytes_left -= size;
+ bytes_used += size;
+ }
+
+ req->first_desc->ctrl |= GR_DESC_OUT_CTRL_EN;
+
+ return 0;
+
+alloc_err:
+ gr_free_dma_desc_chain(ep->dev, req);
+
+ return ret;
+}
+
+/*
+ * Sets up a chain of struct gr_dma_descriptors pointing to buffers that
+ * together covers req->req.length bytes of the buffer at DMA address
+ * req->req.dma for the IN direction.
+ *
+ * When more data is provided than the maximum payload size, the hardware splits
+ * this up into several payloads automatically. Moreover, ep->bytes_per_buffer
+ * is always set to a multiple of the maximum payload (restricted to the valid
+ * number of maximum payloads during high bandwidth isochronous or interrupt
+ * transfers)
+ *
+ * All descriptors are enabled from the beginning and we only generate an
+ * interrupt for the last one indicating that the entire request has been pushed
+ * to hardware.
+ */
+static int gr_setup_in_desc_list(struct gr_ep *ep, struct gr_request *req,
+ gfp_t gfp_flags)
+{
+ u16 bytes_left; /* Bytes left in req to provide descriptors for */
+ u16 bytes_used; /* Bytes in req accommodated for */
+ int ret = 0;
+
+ req->first_desc = NULL; /* Signals that no allocation is done yet */
+ bytes_left = req->req.length;
+ bytes_used = 0;
+ do { /* Allow for zero length packets */
+ dma_addr_t start = req->req.dma + bytes_used;
+ u16 size = min(bytes_left, ep->bytes_per_buffer);
+
+ ret = gr_add_dma_desc(ep, req, start, size, gfp_flags);
+ if (ret)
+ goto alloc_err;
+
+ bytes_left -= size;
+ bytes_used += size;
+ } while (bytes_left > 0);
+
+ /*
+ * Send an extra zero length packet to indicate that no more data is
+ * available when req->req.zero is set and the data length is even
+ * multiples of ep->ep.maxpacket.
+ */
+ if (req->req.zero && (req->req.length % ep->ep.maxpacket == 0)) {
+ ret = gr_add_dma_desc(ep, req, 0, 0, gfp_flags);
+ if (ret)
+ goto alloc_err;
+ }
+
+ /*
+ * For IN packets we only want to know when the last packet has been
+ * transmitted (not just put into internal buffers).
+ */
+ req->last_desc->ctrl |= GR_DESC_IN_CTRL_PI;
+
+ return 0;
+
+alloc_err:
+ gr_free_dma_desc_chain(ep->dev, req);
+
+ return ret;
+}
+
+/* Must be called with dev->lock held */
+static int gr_queue(struct gr_ep *ep, struct gr_request *req, gfp_t gfp_flags)
+{
+ struct gr_udc *dev = ep->dev;
+ int ret;
+
+ if (unlikely(!ep->ep.desc && ep->num != 0)) {
+ dev_err(dev->dev, "No ep descriptor for %s\n", ep->ep.name);
+ return -EINVAL;
+ }
+
+ if (unlikely(!req->req.buf || !list_empty(&req->queue))) {
+ dev_err(dev->dev,
+ "Invalid request for %s: buf=%p list_empty=%d\n",
+ ep->ep.name, req->req.buf, list_empty(&req->queue));
+ return -EINVAL;
+ }
+
+ /*
+ * The DMA controller can not handle smaller OUT buffers than
+ * maxpacket. It could lead to buffer overruns if unexpectedly long
+ * packet are received.
+ */
+ if (!ep->is_in && (req->req.length % ep->ep.maxpacket) != 0) {
+ dev_err(dev->dev,
+ "OUT request length %d is not multiple of maxpacket\n",
+ req->req.length);
+ return -EMSGSIZE;
+ }
+
+ if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)) {
+ dev_err(dev->dev, "-ESHUTDOWN");
+ return -ESHUTDOWN;
+ }
+
+ /* Can't touch registers when suspended */
+ if (dev->ep0state == GR_EP0_SUSPEND) {
+ dev_err(dev->dev, "-EBUSY");
+ return -EBUSY;
+ }
+
+ /* Set up DMA mapping in case the caller didn't */
+ ret = usb_gadget_map_request(&dev->gadget, &req->req, ep->is_in);
+ if (ret) {
+ dev_err(dev->dev, "usb_gadget_map_request");
+ return ret;
+ }
+
+ if (ep->is_in)
+ ret = gr_setup_in_desc_list(ep, req, gfp_flags);
+ else
+ ret = gr_setup_out_desc_list(ep, req, gfp_flags);
+ if (ret)
+ return ret;
+
+ req->req.status = -EINPROGRESS;
+ req->req.actual = 0;
+ list_add_tail(&req->queue, &ep->queue);
+
+ /* Start DMA if not started, otherwise interrupt handler handles it */
+ if (!ep->dma_start && likely(!ep->stopped))
+ gr_start_dma(ep);
+
+ return 0;
+}
+
+/*
+ * Queue a request from within the driver.
+ *
+ * Must be called with dev->lock held.
+ */
+static inline int gr_queue_int(struct gr_ep *ep, struct gr_request *req,
+ gfp_t gfp_flags)
+{
+ if (ep->is_in)
+ gr_dbgprint_request("RESP", ep, req);
+
+ return gr_queue(ep, req, gfp_flags);
+}
+
+/* ---------------------------------------------------------------------- */
+/* General helper functions */
+
+/*
+ * Dequeue ALL requests.
+ *
+ * Must be called with dev->lock held and irqs disabled.
+ */
+static void gr_ep_nuke(struct gr_ep *ep)
+{
+ struct gr_request *req;
+
+ ep->stopped = 1;
+ ep->dma_start = 0;
+ gr_abort_dma(ep);
+
+ while (!list_empty(&ep->queue)) {
+ req = list_first_entry(&ep->queue, struct gr_request, queue);
+ gr_finish_request(ep, req, -ESHUTDOWN);
+ }
+}
+
+/*
+ * Reset the hardware state of this endpoint.
+ *
+ * Must be called with dev->lock held.
+ */
+static void gr_ep_reset(struct gr_ep *ep)
+{
+ gr_write32(&ep->regs->epctrl, 0);
+ gr_write32(&ep->regs->dmactrl, 0);
+
+ ep->ep.maxpacket = MAX_CTRL_PL_SIZE;
+ ep->ep.desc = NULL;
+ ep->stopped = 1;
+ ep->dma_start = 0;
+}
+
+/*
+ * Generate STALL on ep0in/out.
+ *
+ * Must be called with dev->lock held.
+ */
+static void gr_control_stall(struct gr_udc *dev)
+{
+ u32 epctrl;
+
+ epctrl = gr_read32(&dev->epo[0].regs->epctrl);
+ gr_write32(&dev->epo[0].regs->epctrl, epctrl | GR_EPCTRL_CS);
+ epctrl = gr_read32(&dev->epi[0].regs->epctrl);
+ gr_write32(&dev->epi[0].regs->epctrl, epctrl | GR_EPCTRL_CS);
+
+ dev->ep0state = GR_EP0_STALL;
+}
+
+/*
+ * Halts, halts and wedges, or clears halt for an endpoint.
+ *
+ * Must be called with dev->lock held.
+ */
+static int gr_ep_halt_wedge(struct gr_ep *ep, int halt, int wedge, int fromhost)
+{
+ u32 epctrl;
+ int retval = 0;
+
+ if (ep->num && !ep->ep.desc)
+ return -EINVAL;
+
+ if (ep->num && ep->ep.desc->bmAttributes == USB_ENDPOINT_XFER_ISOC)
+ return -EOPNOTSUPP;
+
+ /* Never actually halt ep0, and therefore never clear halt for ep0 */
+ if (!ep->num) {
+ if (halt && !fromhost) {
+ /* ep0 halt from gadget - generate protocol stall */
+ gr_control_stall(ep->dev);
+ dev_dbg(ep->dev->dev, "EP: stall ep0\n");
+ return 0;
+ }
+ return -EINVAL;
+ }
+
+ dev_dbg(ep->dev->dev, "EP: %s halt %s\n",
+ (halt ? (wedge ? "wedge" : "set") : "clear"), ep->ep.name);
+
+ epctrl = gr_read32(&ep->regs->epctrl);
+ if (halt) {
+ /* Set HALT */
+ gr_write32(&ep->regs->epctrl, epctrl | GR_EPCTRL_EH);
+ ep->stopped = 1;
+ if (wedge)
+ ep->wedged = 1;
+ } else {
+ gr_write32(&ep->regs->epctrl, epctrl & ~GR_EPCTRL_EH);
+ ep->stopped = 0;
+ ep->wedged = 0;
+
+ /* Things might have been queued up in the meantime */
+ if (!ep->dma_start)
+ gr_start_dma(ep);
+ }
+
+ return retval;
+}
+
+/* Must be called with dev->lock held */
+static inline void gr_set_ep0state(struct gr_udc *dev, enum gr_ep0state value)
+{
+ if (dev->ep0state != value)
+ dev_vdbg(dev->dev, "STATE: ep0state=%s\n",
+ gr_ep0state_string(value));
+ dev->ep0state = value;
+}
+
+/*
+ * Should only be called when endpoints can not generate interrupts.
+ *
+ * Must be called with dev->lock held.
+ */
+static void gr_disable_interrupts_and_pullup(struct gr_udc *dev)
+{
+ gr_write32(&dev->regs->control, 0);
+ wmb(); /* Make sure that we do not deny one of our interrupts */
+ dev->irq_enabled = 0;
+}
+
+/*
+ * Stop all device activity and disable data line pullup.
+ *
+ * Must be called with dev->lock held and irqs disabled.
+ */
+static void gr_stop_activity(struct gr_udc *dev)
+{
+ struct gr_ep *ep;
+
+ list_for_each_entry(ep, &dev->ep_list, ep_list)
+ gr_ep_nuke(ep);
+
+ gr_disable_interrupts_and_pullup(dev);
+
+ gr_set_ep0state(dev, GR_EP0_DISCONNECT);
+ usb_gadget_set_state(&dev->gadget, USB_STATE_NOTATTACHED);
+}
+
+/* ---------------------------------------------------------------------- */
+/* ep0 setup packet handling */
+
+static void gr_ep0_testmode_complete(struct usb_ep *_ep,
+ struct usb_request *_req)
+{
+ struct gr_ep *ep;
+ struct gr_udc *dev;
+ u32 control;
+
+ ep = container_of(_ep, struct gr_ep, ep);
+ dev = ep->dev;
+
+ spin_lock(&dev->lock);
+
+ control = gr_read32(&dev->regs->control);
+ control |= GR_CONTROL_TM | (dev->test_mode << GR_CONTROL_TS_POS);
+ gr_write32(&dev->regs->control, control);
+
+ spin_unlock(&dev->lock);
+}
+
+static void gr_ep0_dummy_complete(struct usb_ep *_ep, struct usb_request *_req)
+{
+ /* Nothing needs to be done here */
+}
+
+/*
+ * Queue a response on ep0in.
+ *
+ * Must be called with dev->lock held.
+ */
+static int gr_ep0_respond(struct gr_udc *dev, u8 *buf, int length,
+ void (*complete)(struct usb_ep *ep,
+ struct usb_request *req))
+{
+ u8 *reqbuf = dev->ep0reqi->req.buf;
+ int status;
+ int i;
+
+ for (i = 0; i < length; i++)
+ reqbuf[i] = buf[i];
+ dev->ep0reqi->req.length = length;
+ dev->ep0reqi->req.complete = complete;
+
+ status = gr_queue_int(&dev->epi[0], dev->ep0reqi, GFP_ATOMIC);
+ if (status < 0)
+ dev_err(dev->dev,
+ "Could not queue ep0in setup response: %d\n", status);
+
+ return status;
+}
+
+/*
+ * Queue a 2 byte response on ep0in.
+ *
+ * Must be called with dev->lock held.
+ */
+static inline int gr_ep0_respond_u16(struct gr_udc *dev, u16 response)
+{
+ __le16 le_response = cpu_to_le16(response);
+
+ return gr_ep0_respond(dev, (u8 *)&le_response, 2,
+ gr_ep0_dummy_complete);
+}
+
+/*
+ * Queue a ZLP response on ep0in.
+ *
+ * Must be called with dev->lock held.
+ */
+static inline int gr_ep0_respond_empty(struct gr_udc *dev)
+{
+ return gr_ep0_respond(dev, NULL, 0, gr_ep0_dummy_complete);
+}
+
+/*
+ * This is run when a SET_ADDRESS request is received. First writes
+ * the new address to the control register which is updated internally
+ * when the next IN packet is ACKED.
+ *
+ * Must be called with dev->lock held.
+ */
+static void gr_set_address(struct gr_udc *dev, u8 address)
+{
+ u32 control;
+
+ control = gr_read32(&dev->regs->control) & ~GR_CONTROL_UA_MASK;
+ control |= (address << GR_CONTROL_UA_POS) & GR_CONTROL_UA_MASK;
+ control |= GR_CONTROL_SU;
+ gr_write32(&dev->regs->control, control);
+}
+
+/*
+ * Returns negative for STALL, 0 for successful handling and positive for
+ * delegation.
+ *
+ * Must be called with dev->lock held.
+ */
+static int gr_device_request(struct gr_udc *dev, u8 type, u8 request,
+ u16 value, u16 index)
+{
+ u16 response;
+ u8 test;
+
+ switch (request) {
+ case USB_REQ_SET_ADDRESS:
+ dev_dbg(dev->dev, "STATUS: address %d\n", value & 0xff);
+ gr_set_address(dev, value & 0xff);
+ if (value)
+ usb_gadget_set_state(&dev->gadget, USB_STATE_ADDRESS);
+ else
+ usb_gadget_set_state(&dev->gadget, USB_STATE_DEFAULT);
+ return gr_ep0_respond_empty(dev);
+
+ case USB_REQ_GET_STATUS:
+ /* Self powered | remote wakeup */
+ response = 0x0001 | (dev->remote_wakeup ? 0x0002 : 0);
+ return gr_ep0_respond_u16(dev, response);
+
+ case USB_REQ_SET_FEATURE:
+ switch (value) {
+ case USB_DEVICE_REMOTE_WAKEUP:
+ /* Allow remote wakeup */
+ dev->remote_wakeup = 1;
+ return gr_ep0_respond_empty(dev);
+
+ case USB_DEVICE_TEST_MODE:
+ /* The hardware does not support TEST_FORCE_EN */
+ test = index >> 8;
+ if (test >= TEST_J && test <= TEST_PACKET) {
+ dev->test_mode = test;
+ return gr_ep0_respond(dev, NULL, 0,
+ gr_ep0_testmode_complete);
+ }
+ }
+ break;
+
+ case USB_REQ_CLEAR_FEATURE:
+ switch (value) {
+ case USB_DEVICE_REMOTE_WAKEUP:
+ /* Disallow remote wakeup */
+ dev->remote_wakeup = 0;
+ return gr_ep0_respond_empty(dev);
+ }
+ break;
+ }
+
+ return 1; /* Delegate the rest */
+}
+
+/*
+ * Returns negative for STALL, 0 for successful handling and positive for
+ * delegation.
+ *
+ * Must be called with dev->lock held.
+ */
+static int gr_interface_request(struct gr_udc *dev, u8 type, u8 request,
+ u16 value, u16 index)
+{
+ if (dev->gadget.state != USB_STATE_CONFIGURED)
+ return -1;
+
+ /*
+ * Should return STALL for invalid interfaces, but udc driver does not
+ * know anything about that. However, many gadget drivers do not handle
+ * GET_STATUS so we need to take care of that.
+ */
+
+ switch (request) {
+ case USB_REQ_GET_STATUS:
+ return gr_ep0_respond_u16(dev, 0x0000);
+
+ case USB_REQ_SET_FEATURE:
+ case USB_REQ_CLEAR_FEATURE:
+ /*
+ * No possible valid standard requests. Still let gadget drivers
+ * have a go at it.
+ */
+ break;
+ }
+
+ return 1; /* Delegate the rest */
+}
+
+/*
+ * Returns negative for STALL, 0 for successful handling and positive for
+ * delegation.
+ *
+ * Must be called with dev->lock held.
+ */
+static int gr_endpoint_request(struct gr_udc *dev, u8 type, u8 request,
+ u16 value, u16 index)
+{
+ struct gr_ep *ep;
+ int status;
+ int halted;
+ u8 epnum = index & USB_ENDPOINT_NUMBER_MASK;
+ u8 is_in = index & USB_ENDPOINT_DIR_MASK;
+
+ if ((is_in && epnum >= dev->nepi) || (!is_in && epnum >= dev->nepo))
+ return -1;
+
+ if (dev->gadget.state != USB_STATE_CONFIGURED && epnum != 0)
+ return -1;
+
+ ep = (is_in ? &dev->epi[epnum] : &dev->epo[epnum]);
+
+ switch (request) {
+ case USB_REQ_GET_STATUS:
+ halted = gr_read32(&ep->regs->epctrl) & GR_EPCTRL_EH;
+ return gr_ep0_respond_u16(dev, halted ? 0x0001 : 0);
+
+ case USB_REQ_SET_FEATURE:
+ switch (value) {
+ case USB_ENDPOINT_HALT:
+ status = gr_ep_halt_wedge(ep, 1, 0, 1);
+ if (status >= 0)
+ status = gr_ep0_respond_empty(dev);
+ return status;
+ }
+ break;
+
+ case USB_REQ_CLEAR_FEATURE:
+ switch (value) {
+ case USB_ENDPOINT_HALT:
+ if (ep->wedged)
+ return -1;
+ status = gr_ep_halt_wedge(ep, 0, 0, 1);
+ if (status >= 0)
+ status = gr_ep0_respond_empty(dev);
+ return status;
+ }
+ break;
+ }
+
+ return 1; /* Delegate the rest */
+}
+
+/* Must be called with dev->lock held */
+static void gr_ep0out_requeue(struct gr_udc *dev)
+{
+ int ret = gr_queue_int(&dev->epo[0], dev->ep0reqo, GFP_ATOMIC);
+
+ if (ret)
+ dev_err(dev->dev, "Could not queue ep0out setup request: %d\n",
+ ret);
+}
+
+/*
+ * The main function dealing with setup requests on ep0.
+ *
+ * Must be called with dev->lock held and irqs disabled
+ */
+static void gr_ep0_setup(struct gr_udc *dev, struct gr_request *req)
+ __releases(&dev->lock)
+ __acquires(&dev->lock)
+{
+ union {
+ struct usb_ctrlrequest ctrl;
+ u8 raw[8];
+ u32 word[2];
+ } u;
+ u8 type;
+ u8 request;
+ u16 value;
+ u16 index;
+ u16 length;
+ int i;
+ int status;
+
+ /* Restore from ep0 halt */
+ if (dev->ep0state == GR_EP0_STALL) {
+ gr_set_ep0state(dev, GR_EP0_SETUP);
+ if (!req->req.actual)
+ goto out;
+ }
+
+ if (dev->ep0state == GR_EP0_ISTATUS) {
+ gr_set_ep0state(dev, GR_EP0_SETUP);
+ if (req->req.actual > 0)
+ dev_dbg(dev->dev,
+ "Unexpected setup packet at state %s\n",
+ gr_ep0state_string(GR_EP0_ISTATUS));
+ else
+ goto out; /* Got expected ZLP */
+ } else if (dev->ep0state != GR_EP0_SETUP) {
+ dev_info(dev->dev,
+ "Unexpected ep0out request at state %s - stalling\n",
+ gr_ep0state_string(dev->ep0state));
+ gr_control_stall(dev);
+ gr_set_ep0state(dev, GR_EP0_SETUP);
+ goto out;
+ } else if (!req->req.actual) {
+ dev_dbg(dev->dev, "Unexpected ZLP at state %s\n",
+ gr_ep0state_string(dev->ep0state));
+ goto out;
+ }
+
+ /* Handle SETUP packet */
+ for (i = 0; i < req->req.actual; i++)
+ u.raw[i] = ((u8 *)req->req.buf)[i];
+
+ type = u.ctrl.bRequestType;
+ request = u.ctrl.bRequest;
+ value = le16_to_cpu(u.ctrl.wValue);
+ index = le16_to_cpu(u.ctrl.wIndex);
+ length = le16_to_cpu(u.ctrl.wLength);
+
+ gr_dbgprint_devreq(dev, type, request, value, index, length);
+
+ /* Check for data stage */
+ if (length) {
+ if (type & USB_DIR_IN)
+ gr_set_ep0state(dev, GR_EP0_IDATA);
+ else
+ gr_set_ep0state(dev, GR_EP0_ODATA);
+ }
+
+ status = 1; /* Positive status flags delegation */
+ if ((type & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
+ switch (type & USB_RECIP_MASK) {
+ case USB_RECIP_DEVICE:
+ status = gr_device_request(dev, type, request,
+ value, index);
+ break;
+ case USB_RECIP_ENDPOINT:
+ status = gr_endpoint_request(dev, type, request,
+ value, index);
+ break;
+ case USB_RECIP_INTERFACE:
+ status = gr_interface_request(dev, type, request,
+ value, index);
+ break;
+ }
+ }
+
+ if (status > 0) {
+ spin_unlock(&dev->lock);
+
+ dev_vdbg(dev->dev, "DELEGATE\n");
+ status = dev->driver->setup(&dev->gadget, &u.ctrl);
+
+ spin_lock(&dev->lock);
+ }
+
+ /* Generate STALL on both ep0out and ep0in if requested */
+ if (unlikely(status < 0)) {
+ dev_vdbg(dev->dev, "STALL\n");
+ gr_control_stall(dev);
+ }
+
+ if ((type & USB_TYPE_MASK) == USB_TYPE_STANDARD &&
+ request == USB_REQ_SET_CONFIGURATION) {
+ if (!value) {
+ dev_dbg(dev->dev, "STATUS: deconfigured\n");
+ usb_gadget_set_state(&dev->gadget, USB_STATE_ADDRESS);
+ } else if (status >= 0) {
+ /* Not configured unless gadget OK:s it */
+ dev_dbg(dev->dev, "STATUS: configured: %d\n", value);
+ usb_gadget_set_state(&dev->gadget,
+ USB_STATE_CONFIGURED);
+ }
+ }
+
+ /* Get ready for next stage */
+ if (dev->ep0state == GR_EP0_ODATA)
+ gr_set_ep0state(dev, GR_EP0_OSTATUS);
+ else if (dev->ep0state == GR_EP0_IDATA)
+ gr_s