| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers |
| * |
| * Copyright (C) 2004 David Brownell |
| * |
| * Ported to U-Boot by: Thomas Smits <ts.smits@gmail.com> and |
| * Remy Bohmer <linux@bohmer.net> |
| */ |
| |
| #include <linux/usb/ch9.h> |
| #include <linux/errno.h> |
| #include <linux/usb/gadget.h> |
| #include <asm/unaligned.h> |
| #include "gadget_chips.h" |
| |
| #define isdigit(c) ('0' <= (c) && (c) <= '9') |
| |
| /* we must assign addresses for configurable endpoints (like net2280) */ |
| static unsigned epnum; |
| |
| /* #define MANY_ENDPOINTS */ |
| #ifdef MANY_ENDPOINTS |
| /* more than 15 configurable endpoints */ |
| static unsigned in_epnum; |
| #endif |
| |
| |
| /* |
| * 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 |
| ) |
| { |
| u8 type; |
| const char *tmp; |
| u16 max; |
| |
| /* endpoint already claimed? */ |
| if (NULL != ep->driver_data) |
| return 0; |
| |
| /* only support ep0 for portable CONTROL traffic */ |
| type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; |
| 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; |
| 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; |
| } |
| } |
| } |
| |
| /* 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 & le16_to_cpu(get_unaligned(&desc->wMaxPacketSize)); |
| switch (type) { |
| case USB_ENDPOINT_XFER_INT: |
| /* INT: limit 64 bytes full speed, 1024 high speed */ |
| if (!gadget->is_dualspeed && max > 64) |
| return 0; |
| /* FALLTHROUGH */ |
| |
| case USB_ENDPOINT_XFER_ISOC: |
| /* ISO: limit 1023 bytes full speed, 1024 high speed */ |
| if (ep->maxpacket < max) |
| return 0; |
| if (!gadget->is_dualspeed && max > 1023) |
| return 0; |
| |
| /* BOTH: "high bandwidth" works only at high speed */ |
| if ((get_unaligned(&desc->wMaxPacketSize) & |
| __constant_cpu_to_le16(3<<11))) { |
| if (!gadget->is_dualspeed) |
| return 0; |
| /* configure your hardware with enough buffering!! */ |
| } |
| break; |
| } |
| |
| /* MATCH!! */ |
| |
| /* report address */ |
| if (isdigit(ep->name[2])) { |
| u8 num = dectoul(&ep->name[2], NULL); |
| desc->bEndpointAddress |= num; |
| #ifdef MANY_ENDPOINTS |
| } else if (desc->bEndpointAddress & USB_DIR_IN) { |
| if (++in_epnum > 15) |
| return 0; |
| desc->bEndpointAddress = USB_DIR_IN | in_epnum; |
| #endif |
| } else { |
| if (++epnum > 15) |
| return 0; |
| desc->bEndpointAddress |= epnum; |
| } |
| |
| /* report (variable) full speed bulk maxpacket */ |
| if (USB_ENDPOINT_XFER_BULK == type) { |
| int size = ep->maxpacket; |
| |
| /* min() doesn't work on bitfields with gcc-3.5 */ |
| if (size > 64) |
| size = 64; |
| put_unaligned(cpu_to_le16(size), &desc->wMaxPacketSize); |
| } |
| |
| if (gadget->ops->ep_conf) |
| return gadget->ops->ep_conf(gadget, ep, desc); |
| |
| 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 - 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 |
| ) |
| { |
| struct usb_ep *ep = NULL; |
| 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)) |
| return ep; |
| ep = find_ep(gadget, "ep-f"); |
| if (ep && ep_matches(gadget, ep, desc)) |
| return 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)) |
| return 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)) |
| return ep; |
| } |
| |
| } else if (gadget_is_sh(gadget) && USB_ENDPOINT_XFER_INT == type) { |
| /* single buffering is enough; maybe 8 byte fifo is too */ |
| ep = find_ep(gadget, "ep3in-bulk"); |
| if (ep && ep_matches(gadget, ep, desc)) |
| return ep; |
| |
| } else if (gadget_is_mq11xx(gadget) && USB_ENDPOINT_XFER_INT == type) { |
| ep = find_ep(gadget, "ep1-bulk"); |
| if (ep && ep_matches(gadget, ep, desc)) |
| return ep; |
| #ifndef CONFIG_SPL_BUILD |
| } else if (gadget_is_dwc3(gadget)) { |
| const char *name = NULL; |
| /* |
| * First try standard, common configuration: ep1in-bulk, |
| * ep2out-bulk, ep3in-int to match other udc drivers to avoid |
| * confusion in already deployed software (endpoint numbers |
| * hardcoded in userspace software/drivers) |
| */ |
| if ((desc->bEndpointAddress & USB_DIR_IN) && |
| type == USB_ENDPOINT_XFER_BULK) |
| name = "ep1in"; |
| else if ((desc->bEndpointAddress & USB_DIR_IN) == 0 && |
| type == USB_ENDPOINT_XFER_BULK) |
| name = "ep2out"; |
| else if ((desc->bEndpointAddress & USB_DIR_IN) && |
| type == USB_ENDPOINT_XFER_INT) |
| name = "ep3in"; |
| |
| if (name) |
| ep = find_ep(gadget, name); |
| if (ep && ep_matches(gadget, ep, desc)) |
| return ep; |
| #endif |
| } |
| |
| if (gadget->ops->match_ep) |
| ep = gadget->ops->match_ep(gadget, desc, NULL); |
| |
| /* 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)) |
| return ep; |
| } |
| |
| /* Fail */ |
| return NULL; |
| } |
| |
| /** |
| * 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; |
| } |
| #ifdef MANY_ENDPOINTS |
| in_epnum = 0; |
| #endif |
| epnum = 0; |
| } |