1 /* 2 * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers 3 * 4 * Copyright (C) 2004 David Brownell 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and 21 * Remy Bohmer <linux@bohmer.net> 22 */ 23 24 #include <common.h> 25 #include <linux/usb/ch9.h> 26 #include <asm/errno.h> 27 #include <linux/usb/gadget.h> 28 #include <asm/unaligned.h> 29 #include "gadget_chips.h" 30 31 #define isdigit(c) ('0' <= (c) && (c) <= '9') 32 33 /* we must assign addresses for configurable endpoints (like net2280) */ 34 static unsigned epnum; 35 36 /* #define MANY_ENDPOINTS */ 37 #ifdef MANY_ENDPOINTS 38 /* more than 15 configurable endpoints */ 39 static unsigned in_epnum; 40 #endif 41 42 43 /* 44 * This should work with endpoints from controller drivers sharing the 45 * same endpoint naming convention. By example: 46 * 47 * - ep1, ep2, ... address is fixed, not direction or type 48 * - ep1in, ep2out, ... address and direction are fixed, not type 49 * - ep1-bulk, ep2-bulk, ... address and type are fixed, not direction 50 * - ep1in-bulk, ep2out-iso, ... all three are fixed 51 * - ep-* ... no functionality restrictions 52 * 53 * Type suffixes are "-bulk", "-iso", or "-int". Numbers are decimal. 54 * Less common restrictions are implied by gadget_is_*(). 55 * 56 * NOTE: each endpoint is unidirectional, as specified by its USB 57 * descriptor; and isn't specific to a configuration or altsetting. 58 */ 59 static int ep_matches( 60 struct usb_gadget *gadget, 61 struct usb_ep *ep, 62 struct usb_endpoint_descriptor *desc 63 ) 64 { 65 u8 type; 66 const char *tmp; 67 u16 max; 68 69 /* endpoint already claimed? */ 70 if (NULL != ep->driver_data) 71 return 0; 72 73 /* only support ep0 for portable CONTROL traffic */ 74 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; 75 if (USB_ENDPOINT_XFER_CONTROL == type) 76 return 0; 77 78 /* some other naming convention */ 79 if ('e' != ep->name[0]) 80 return 0; 81 82 /* type-restriction: "-iso", "-bulk", or "-int". 83 * direction-restriction: "in", "out". 84 */ 85 if ('-' != ep->name[2]) { 86 tmp = strrchr(ep->name, '-'); 87 if (tmp) { 88 switch (type) { 89 case USB_ENDPOINT_XFER_INT: 90 /* bulk endpoints handle interrupt transfers, 91 * except the toggle-quirky iso-synch kind 92 */ 93 if ('s' == tmp[2]) /* == "-iso" */ 94 return 0; 95 /* for now, avoid PXA "interrupt-in"; 96 * it's documented as never using DATA1. 97 */ 98 if (gadget_is_pxa(gadget) 99 && 'i' == tmp[1]) 100 return 0; 101 break; 102 case USB_ENDPOINT_XFER_BULK: 103 if ('b' != tmp[1]) /* != "-bulk" */ 104 return 0; 105 break; 106 case USB_ENDPOINT_XFER_ISOC: 107 if ('s' != tmp[2]) /* != "-iso" */ 108 return 0; 109 } 110 } else { 111 tmp = ep->name + strlen(ep->name); 112 } 113 114 /* direction-restriction: "..in-..", "out-.." */ 115 tmp--; 116 if (!isdigit(*tmp)) { 117 if (desc->bEndpointAddress & USB_DIR_IN) { 118 if ('n' != *tmp) 119 return 0; 120 } else { 121 if ('t' != *tmp) 122 return 0; 123 } 124 } 125 } 126 127 /* endpoint maxpacket size is an input parameter, except for bulk 128 * where it's an output parameter representing the full speed limit. 129 * the usb spec fixes high speed bulk maxpacket at 512 bytes. 130 */ 131 max = 0x7ff & le16_to_cpu(get_unaligned(&desc->wMaxPacketSize)); 132 switch (type) { 133 case USB_ENDPOINT_XFER_INT: 134 /* INT: limit 64 bytes full speed, 1024 high speed */ 135 if (!gadget->is_dualspeed && max > 64) 136 return 0; 137 /* FALLTHROUGH */ 138 139 case USB_ENDPOINT_XFER_ISOC: 140 /* ISO: limit 1023 bytes full speed, 1024 high speed */ 141 if (ep->maxpacket < max) 142 return 0; 143 if (!gadget->is_dualspeed && max > 1023) 144 return 0; 145 146 /* BOTH: "high bandwidth" works only at high speed */ 147 if ((get_unaligned(&desc->wMaxPacketSize) & 148 __constant_cpu_to_le16(3<<11))) { 149 if (!gadget->is_dualspeed) 150 return 0; 151 /* configure your hardware with enough buffering!! */ 152 } 153 break; 154 } 155 156 /* MATCH!! */ 157 158 /* report address */ 159 if (isdigit(ep->name[2])) { 160 u8 num = simple_strtoul(&ep->name[2], NULL, 10); 161 desc->bEndpointAddress |= num; 162 #ifdef MANY_ENDPOINTS 163 } else if (desc->bEndpointAddress & USB_DIR_IN) { 164 if (++in_epnum > 15) 165 return 0; 166 desc->bEndpointAddress = USB_DIR_IN | in_epnum; 167 #endif 168 } else { 169 if (++epnum > 15) 170 return 0; 171 desc->bEndpointAddress |= epnum; 172 } 173 174 /* report (variable) full speed bulk maxpacket */ 175 if (USB_ENDPOINT_XFER_BULK == type) { 176 int size = ep->maxpacket; 177 178 /* min() doesn't work on bitfields with gcc-3.5 */ 179 if (size > 64) 180 size = 64; 181 put_unaligned(cpu_to_le16(size), &desc->wMaxPacketSize); 182 } 183 return 1; 184 } 185 186 static struct usb_ep * 187 find_ep(struct usb_gadget *gadget, const char *name) 188 { 189 struct usb_ep *ep; 190 191 list_for_each_entry(ep, &gadget->ep_list, ep_list) { 192 if (0 == strcmp(ep->name, name)) 193 return ep; 194 } 195 return NULL; 196 } 197 198 /** 199 * usb_ep_autoconfig - choose an endpoint matching the descriptor 200 * @gadget: The device to which the endpoint must belong. 201 * @desc: Endpoint descriptor, with endpoint direction and transfer mode 202 * initialized. For periodic transfers, the maximum packet 203 * size must also be initialized. This is modified on success. 204 * 205 * By choosing an endpoint to use with the specified descriptor, this 206 * routine simplifies writing gadget drivers that work with multiple 207 * USB device controllers. The endpoint would be passed later to 208 * usb_ep_enable(), along with some descriptor. 209 * 210 * That second descriptor won't always be the same as the first one. 211 * For example, isochronous endpoints can be autoconfigured for high 212 * bandwidth, and then used in several lower bandwidth altsettings. 213 * Also, high and full speed descriptors will be different. 214 * 215 * Be sure to examine and test the results of autoconfiguration on your 216 * hardware. This code may not make the best choices about how to use the 217 * USB controller, and it can't know all the restrictions that may apply. 218 * Some combinations of driver and hardware won't be able to autoconfigure. 219 * 220 * On success, this returns an un-claimed usb_ep, and modifies the endpoint 221 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value 222 * is initialized as if the endpoint were used at full speed. To prevent 223 * the endpoint from being returned by a later autoconfig call, claim it 224 * by assigning ep->driver_data to some non-null value. 225 * 226 * On failure, this returns a null endpoint descriptor. 227 */ 228 struct usb_ep *usb_ep_autoconfig( 229 struct usb_gadget *gadget, 230 struct usb_endpoint_descriptor *desc 231 ) 232 { 233 struct usb_ep *ep; 234 u8 type; 235 236 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; 237 238 /* First, apply chip-specific "best usage" knowledge. 239 * This might make a good usb_gadget_ops hook ... 240 */ 241 if (gadget_is_net2280(gadget) && type == USB_ENDPOINT_XFER_INT) { 242 /* ep-e, ep-f are PIO with only 64 byte fifos */ 243 ep = find_ep(gadget, "ep-e"); 244 if (ep && ep_matches(gadget, ep, desc)) 245 return ep; 246 ep = find_ep(gadget, "ep-f"); 247 if (ep && ep_matches(gadget, ep, desc)) 248 return ep; 249 250 } else if (gadget_is_goku(gadget)) { 251 if (USB_ENDPOINT_XFER_INT == type) { 252 /* single buffering is enough */ 253 ep = find_ep(gadget, "ep3-bulk"); 254 if (ep && ep_matches(gadget, ep, desc)) 255 return ep; 256 } else if (USB_ENDPOINT_XFER_BULK == type 257 && (USB_DIR_IN & desc->bEndpointAddress)) { 258 /* DMA may be available */ 259 ep = find_ep(gadget, "ep2-bulk"); 260 if (ep && ep_matches(gadget, ep, desc)) 261 return ep; 262 } 263 264 } else if (gadget_is_sh(gadget) && USB_ENDPOINT_XFER_INT == type) { 265 /* single buffering is enough; maybe 8 byte fifo is too */ 266 ep = find_ep(gadget, "ep3in-bulk"); 267 if (ep && ep_matches(gadget, ep, desc)) 268 return ep; 269 270 } else if (gadget_is_mq11xx(gadget) && USB_ENDPOINT_XFER_INT == type) { 271 ep = find_ep(gadget, "ep1-bulk"); 272 if (ep && ep_matches(gadget, ep, desc)) 273 return ep; 274 } 275 276 /* Second, look at endpoints until an unclaimed one looks usable */ 277 list_for_each_entry(ep, &gadget->ep_list, ep_list) { 278 if (ep_matches(gadget, ep, desc)) 279 return ep; 280 } 281 282 /* Fail */ 283 return NULL; 284 } 285 286 /** 287 * usb_ep_autoconfig_reset - reset endpoint autoconfig state 288 * @gadget: device for which autoconfig state will be reset 289 * 290 * Use this for devices where one configuration may need to assign 291 * endpoint resources very differently from the next one. It clears 292 * state such as ep->driver_data and the record of assigned endpoints 293 * used by usb_ep_autoconfig(). 294 */ 295 void usb_ep_autoconfig_reset(struct usb_gadget *gadget) 296 { 297 struct usb_ep *ep; 298 299 list_for_each_entry(ep, &gadget->ep_list, ep_list) { 300 ep->driver_data = NULL; 301 } 302 #ifdef MANY_ENDPOINTS 303 in_epnum = 0; 304 #endif 305 epnum = 0; 306 } 307