--- /dev/null
+/*
+ * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers
+ *
+ * Copyright (C) 2004 David Brownell
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/device.h>
+
+#include <linux/ctype.h>
+#include <linux/string.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+
+#include "gadget_chips.h"
+
+/*
+ * This should work with endpoints from controller drivers sharing the
+ * same endpoint naming convention. By example:
+ *
+ * - ep1, ep2, ... address is fixed, not direction or type
+ * - ep1in, ep2out, ... address and direction are fixed, not type
+ * - ep1-bulk, ep2-bulk, ... address and type are fixed, not direction
+ * - ep1in-bulk, ep2out-iso, ... all three are fixed
+ * - ep-* ... no functionality restrictions
+ *
+ * Type suffixes are "-bulk", "-iso", or "-int". Numbers are decimal.
+ * Less common restrictions are implied by gadget_is_*().
+ *
+ * NOTE: each endpoint is unidirectional, as specified by its USB
+ * descriptor; and isn't specific to a configuration or altsetting.
+ */
+static int
+ep_matches (
+ struct usb_gadget *gadget,
+ struct usb_ep *ep,
+ struct usb_endpoint_descriptor *desc,
+ struct usb_ss_ep_comp_descriptor *ep_comp
+)
+{
+ u8 type;
+ const char *tmp;
+ u16 max;
+
+ int num_req_streams = 0;
+
+ /* endpoint already claimed? */
+ if (NULL != ep->driver_data)
+ return 0;
+
+ /* only support ep0 for portable CONTROL traffic */
+ type = usb_endpoint_type(desc);
+ if (USB_ENDPOINT_XFER_CONTROL == type)
+ return 0;
+
+ /* some other naming convention */
+ if ('e' != ep->name[0])
+ return 0;
+
+ /* type-restriction: "-iso", "-bulk", or "-int".
+ * direction-restriction: "in", "out".
+ */
+ if ('-' != ep->name[2]) {
+ tmp = strrchr (ep->name, '-');
+ if (tmp) {
+ switch (type) {
+ case USB_ENDPOINT_XFER_INT:
+ /* bulk endpoints handle interrupt transfers,
+ * except the toggle-quirky iso-synch kind
+ */
+ if ('s' == tmp[2]) // == "-iso"
+ return 0;
+ /* for now, avoid PXA "interrupt-in";
+ * it's documented as never using DATA1.
+ */
+ if (gadget_is_pxa (gadget)
+ && 'i' == tmp [1])
+ return 0;
+ break;
+ case USB_ENDPOINT_XFER_BULK:
+ if ('b' != tmp[1]) // != "-bulk"
+ return 0;
+ break;
+ case USB_ENDPOINT_XFER_ISOC:
+ if ('s' != tmp[2]) // != "-iso"
+ return 0;
+ }
+ } else {
+ tmp = ep->name + strlen (ep->name);
+ }
+
+ /* direction-restriction: "..in-..", "out-.." */
+ tmp--;
+ if (!isdigit (*tmp)) {
+ if (desc->bEndpointAddress & USB_DIR_IN) {
+ if ('n' != *tmp)
+ return 0;
+ } else {
+ if ('t' != *tmp)
+ return 0;
+ }
+ }
+ }
+
+ /*
+ * Get the number of required streams from the EP companion
+ * descriptor and see if the EP matches it
+ */
+ if (usb_endpoint_xfer_bulk(desc)) {
+ if (ep_comp && gadget->max_speed >= USB_SPEED_SUPER) {
+ num_req_streams = ep_comp->bmAttributes & 0x1f;
+ if (num_req_streams > ep->max_streams)
+ return 0;
+ }
+
+ }
+
+ /*
+ * If the protocol driver hasn't yet decided on wMaxPacketSize
+ * and wants to know the maximum possible, provide the info.
+ */
+ if (desc->wMaxPacketSize == 0)
+ desc->wMaxPacketSize = cpu_to_le16(ep->maxpacket_limit);
+
+ /* endpoint maxpacket size is an input parameter, except for bulk
+ * where it's an output parameter representing the full speed limit.
+ * the usb spec fixes high speed bulk maxpacket at 512 bytes.
+ */
+ max = 0x7ff & usb_endpoint_maxp(desc);
+ switch (type) {
+ case USB_ENDPOINT_XFER_INT:
+ /* INT: limit 64 bytes full speed, 1024 high/super speed */
+ if (!gadget_is_dualspeed(gadget) && max > 64)
+ return 0;
+ /* FALLTHROUGH */
+
+ case USB_ENDPOINT_XFER_ISOC:
+ /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
+ if (ep->maxpacket_limit < max)
+ return 0;
+ if (!gadget_is_dualspeed(gadget) && max > 1023)
+ return 0;
+
+ /* BOTH: "high bandwidth" works only at high speed */
+ if ((desc->wMaxPacketSize & cpu_to_le16(3<<11))) {
+ if (!gadget_is_dualspeed(gadget))
+ return 0;
+ /* configure your hardware with enough buffering!! */
+ }
+ break;
+ }
+
+ /* MATCH!! */
+
+ /* report address */
+ desc->bEndpointAddress &= USB_DIR_IN;
+ if (isdigit (ep->name [2])) {
+ u8 num = simple_strtoul (&ep->name [2], NULL, 10);
+ desc->bEndpointAddress |= num;
+ } else if (desc->bEndpointAddress & USB_DIR_IN) {
+ if (++gadget->in_epnum > 15)
+ return 0;
+ desc->bEndpointAddress = USB_DIR_IN | gadget->in_epnum;
+ } else {
+ if (++gadget->out_epnum > 15)
+ return 0;
+ desc->bEndpointAddress |= gadget->out_epnum;
+ }
+
+ /* report (variable) full speed bulk maxpacket */
+ if ((USB_ENDPOINT_XFER_BULK == type) && !ep_comp) {
+ int size = ep->maxpacket_limit;
+
+ /* min() doesn't work on bitfields with gcc-3.5 */
+ if (size > 64)
+ size = 64;
+ desc->wMaxPacketSize = cpu_to_le16(size);
+ }
+ ep->address = desc->bEndpointAddress;
+ return 1;
+}
+
+static struct usb_ep *
+find_ep (struct usb_gadget *gadget, const char *name)
+{
+ struct usb_ep *ep;
+
+ list_for_each_entry (ep, &gadget->ep_list, ep_list) {
+ if (0 == strcmp (ep->name, name))
+ return ep;
+ }
+ return NULL;
+}
+
+/**
+ * usb_ep_autoconfig_ss() - choose an endpoint matching the ep
+ * descriptor and ep companion descriptor
+ * @gadget: The device to which the endpoint must belong.
+ * @desc: Endpoint descriptor, with endpoint direction and transfer mode
+ * initialized. For periodic transfers, the maximum packet
+ * size must also be initialized. This is modified on
+ * success.
+ * @ep_comp: Endpoint companion descriptor, with the required
+ * number of streams. Will be modified when the chosen EP
+ * supports a different number of streams.
+ *
+ * This routine replaces the usb_ep_autoconfig when needed
+ * superspeed enhancments. If such enhancemnets are required,
+ * the FD should call usb_ep_autoconfig_ss directly and provide
+ * the additional ep_comp parameter.
+ *
+ * By choosing an endpoint to use with the specified descriptor,
+ * this routine simplifies writing gadget drivers that work with
+ * multiple USB device controllers. The endpoint would be
+ * passed later to usb_ep_enable(), along with some descriptor.
+ *
+ * That second descriptor won't always be the same as the first one.
+ * For example, isochronous endpoints can be autoconfigured for high
+ * bandwidth, and then used in several lower bandwidth altsettings.
+ * Also, high and full speed descriptors will be different.
+ *
+ * Be sure to examine and test the results of autoconfiguration
+ * on your hardware. This code may not make the best choices
+ * about how to use the USB controller, and it can't know all
+ * the restrictions that may apply. Some combinations of driver
+ * and hardware won't be able to autoconfigure.
+ *
+ * On success, this returns an un-claimed usb_ep, and modifies the endpoint
+ * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
+ * is initialized as if the endpoint were used at full speed and
+ * the bmAttribute field in the ep companion descriptor is
+ * updated with the assigned number of streams if it is
+ * different from the original value. To prevent the endpoint
+ * from being returned by a later autoconfig call, claim it by
+ * assigning ep->driver_data to some non-null value.
+ *
+ * On failure, this returns a null endpoint descriptor.
+ */
+struct usb_ep *usb_ep_autoconfig_ss(
+ struct usb_gadget *gadget,
+ struct usb_endpoint_descriptor *desc,
+ struct usb_ss_ep_comp_descriptor *ep_comp
+)
+{
+ struct usb_ep *ep;
+ u8 type;
+
+ type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
+
+ /* First, apply chip-specific "best usage" knowledge.
+ * This might make a good usb_gadget_ops hook ...
+ */
+ if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) {
+ /* ep-e, ep-f are PIO with only 64 byte fifos */
+ ep = find_ep (gadget, "ep-e");
+ if (ep && ep_matches(gadget, ep, desc, ep_comp))
+ goto found_ep;
+ ep = find_ep (gadget, "ep-f");
+ if (ep && ep_matches(gadget, ep, desc, ep_comp))
+ goto found_ep;
+
+ } else if (gadget_is_goku (gadget)) {
+ if (USB_ENDPOINT_XFER_INT == type) {
+ /* single buffering is enough */
+ ep = find_ep(gadget, "ep3-bulk");
+ if (ep && ep_matches(gadget, ep, desc, ep_comp))
+ goto found_ep;
+ } else if (USB_ENDPOINT_XFER_BULK == type
+ && (USB_DIR_IN & desc->bEndpointAddress)) {
+ /* DMA may be available */
+ ep = find_ep(gadget, "ep2-bulk");
+ if (ep && ep_matches(gadget, ep, desc,
+ ep_comp))
+ goto found_ep;
+ }
+
+#ifdef CONFIG_BLACKFIN
+ } else if (gadget_is_musbhdrc(gadget)) {
+ if ((USB_ENDPOINT_XFER_BULK == type) ||
+ (USB_ENDPOINT_XFER_ISOC == type)) {
+ if (USB_DIR_IN & desc->bEndpointAddress)
+ ep = find_ep (gadget, "ep5in");
+ else
+ ep = find_ep (gadget, "ep6out");
+ } else if (USB_ENDPOINT_XFER_INT == type) {
+ if (USB_DIR_IN & desc->bEndpointAddress)
+ ep = find_ep(gadget, "ep1in");
+ else
+ ep = find_ep(gadget, "ep2out");
+ } else
+ ep = NULL;
+ if (ep && ep_matches(gadget, ep, desc, ep_comp))
+ goto found_ep;
+#endif
+ }
+
+ /* Second, look at endpoints until an unclaimed one looks usable */
+ list_for_each_entry (ep, &gadget->ep_list, ep_list) {
+ if (ep_matches(gadget, ep, desc, ep_comp))
+ goto found_ep;
+ }
+
+ /* Fail */
+ return NULL;
+found_ep:
+ ep->desc = NULL;
+ ep->comp_desc = NULL;
+ return ep;
+}
+EXPORT_SYMBOL_GPL(usb_ep_autoconfig_ss);
+
+/**
+ * usb_ep_autoconfig() - choose an endpoint matching the
+ * descriptor
+ * @gadget: The device to which the endpoint must belong.
+ * @desc: Endpoint descriptor, with endpoint direction and transfer mode
+ * initialized. For periodic transfers, the maximum packet
+ * size must also be initialized. This is modified on success.
+ *
+ * By choosing an endpoint to use with the specified descriptor, this
+ * routine simplifies writing gadget drivers that work with multiple
+ * USB device controllers. The endpoint would be passed later to
+ * usb_ep_enable(), along with some descriptor.
+ *
+ * That second descriptor won't always be the same as the first one.
+ * For example, isochronous endpoints can be autoconfigured for high
+ * bandwidth, and then used in several lower bandwidth altsettings.
+ * Also, high and full speed descriptors will be different.
+ *
+ * Be sure to examine and test the results of autoconfiguration on your
+ * hardware. This code may not make the best choices about how to use the
+ * USB controller, and it can't know all the restrictions that may apply.
+ * Some combinations of driver and hardware won't be able to autoconfigure.
+ *
+ * On success, this returns an un-claimed usb_ep, and modifies the endpoint
+ * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
+ * is initialized as if the endpoint were used at full speed. To prevent
+ * the endpoint from being returned by a later autoconfig call, claim it
+ * by assigning ep->driver_data to some non-null value.
+ *
+ * On failure, this returns a null endpoint descriptor.
+ */
+struct usb_ep *usb_ep_autoconfig(
+ struct usb_gadget *gadget,
+ struct usb_endpoint_descriptor *desc
+)
+{
+ return usb_ep_autoconfig_ss(gadget, desc, NULL);
+}
+EXPORT_SYMBOL_GPL(usb_ep_autoconfig);
+
+/**
+ * usb_ep_autoconfig_reset - reset endpoint autoconfig state
+ * @gadget: device for which autoconfig state will be reset
+ *
+ * Use this for devices where one configuration may need to assign
+ * endpoint resources very differently from the next one. It clears
+ * state such as ep->driver_data and the record of assigned endpoints
+ * used by usb_ep_autoconfig().
+ */
+void usb_ep_autoconfig_reset (struct usb_gadget *gadget)
+{
+ struct usb_ep *ep;
+
+ list_for_each_entry (ep, &gadget->ep_list, ep_list) {
+ ep->driver_data = NULL;
+ }
+ gadget->in_epnum = 0;
+ gadget->out_epnum = 0;
+}
+EXPORT_SYMBOL_GPL(usb_ep_autoconfig_reset);
Code Review / kvmfornfv.git / blobdiff