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 "gadget_chips.h" 29 30 #define isdigit(c) ('0' <= (c) && (c) <= '9') 31 32 /* we must assign addresses for configurable endpoints (like net2280) */ 33 static unsigned epnum; 34 35 // #define MANY_ENDPOINTS 36 #ifdef MANY_ENDPOINTS 37 /* more than 15 configurable endpoints */ 38 static unsigned in_epnum; 39 #endif 40 41 42 /* 43 * This should work with endpoints from controller drivers sharing the 44 * same endpoint naming convention. By example: 45 * 46 * - ep1, ep2, ... address is fixed, not direction or type 47 * - ep1in, ep2out, ... address and direction are fixed, not type 48 * - ep1-bulk, ep2-bulk, ... address and type are fixed, not direction 49 * - ep1in-bulk, ep2out-iso, ... all three are fixed 50 * - ep-* ... no functionality restrictions 51 * 52 * Type suffixes are "-bulk", "-iso", or "-int". Numbers are decimal. 53 * Less common restrictions are implied by gadget_is_*(). 54 * 55 * NOTE: each endpoint is unidirectional, as specified by its USB 56 * descriptor; and isn't specific to a configuration or altsetting. 57 */ 58 static int 59 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(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 ((desc->wMaxPacketSize & __constant_cpu_to_le16(3<<11))) { 148 if (!gadget->is_dualspeed) 149 return 0; 150 /* configure your hardware with enough buffering!! */ 151 } 152 break; 153 } 154 155 /* MATCH!! */ 156 157 /* report address */ 158 if (isdigit (ep->name [2])) { 159 u8 num = simple_strtoul (&ep->name [2], NULL, 10); 160 desc->bEndpointAddress |= num; 161 #ifdef MANY_ENDPOINTS 162 } else if (desc->bEndpointAddress & USB_DIR_IN) { 163 if (++in_epnum > 15) 164 return 0; 165 desc->bEndpointAddress = USB_DIR_IN | in_epnum; 166 #endif 167 } else { 168 if (++epnum > 15) 169 return 0; 170 desc->bEndpointAddress |= epnum; 171 } 172 173 /* report (variable) full speed bulk maxpacket */ 174 if (USB_ENDPOINT_XFER_BULK == type) { 175 int size = ep->maxpacket; 176 177 /* min() doesn't work on bitfields with gcc-3.5 */ 178 if (size > 64) 179 size = 64; 180 desc->wMaxPacketSize = cpu_to_le16(size); 181 } 182 return 1; 183 } 184 185 static struct usb_ep * 186 find_ep (struct usb_gadget *gadget, const char *name) 187 { 188 struct usb_ep *ep; 189 190 list_for_each_entry (ep, &gadget->ep_list, ep_list) { 191 if (0 == strcmp (ep->name, name)) 192 return ep; 193 } 194 return NULL; 195 } 196 197 /** 198 * usb_ep_autoconfig - choose an endpoint matching the descriptor 199 * @gadget: The device to which the endpoint must belong. 200 * @desc: Endpoint descriptor, with endpoint direction and transfer mode 201 * initialized. For periodic transfers, the maximum packet 202 * size must also be initialized. This is modified on success. 203 * 204 * By choosing an endpoint to use with the specified descriptor, this 205 * routine simplifies writing gadget drivers that work with multiple 206 * USB device controllers. The endpoint would be passed later to 207 * usb_ep_enable(), along with some descriptor. 208 * 209 * That second descriptor won't always be the same as the first one. 210 * For example, isochronous endpoints can be autoconfigured for high 211 * bandwidth, and then used in several lower bandwidth altsettings. 212 * Also, high and full speed descriptors will be different. 213 * 214 * Be sure to examine and test the results of autoconfiguration on your 215 * hardware. This code may not make the best choices about how to use the 216 * USB controller, and it can't know all the restrictions that may apply. 217 * Some combinations of driver and hardware won't be able to autoconfigure. 218 * 219 * On success, this returns an un-claimed usb_ep, and modifies the endpoint 220 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value 221 * is initialized as if the endpoint were used at full speed. To prevent 222 * the endpoint from being returned by a later autoconfig call, claim it 223 * by assigning ep->driver_data to some non-null value. 224 * 225 * On failure, this returns a null endpoint descriptor. 226 */ 227 struct usb_ep * usb_ep_autoconfig ( 228 struct usb_gadget *gadget, 229 struct usb_endpoint_descriptor *desc 230 ) 231 { 232 struct usb_ep *ep; 233 u8 type; 234 235 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; 236 237 /* First, apply chip-specific "best usage" knowledge. 238 * This might make a good usb_gadget_ops hook ... 239 */ 240 if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) { 241 /* ep-e, ep-f are PIO with only 64 byte fifos */ 242 ep = find_ep (gadget, "ep-e"); 243 if (ep && ep_matches (gadget, ep, desc)) 244 return ep; 245 ep = find_ep (gadget, "ep-f"); 246 if (ep && ep_matches (gadget, ep, desc)) 247 return ep; 248 249 } else if (gadget_is_goku (gadget)) { 250 if (USB_ENDPOINT_XFER_INT == type) { 251 /* single buffering is enough */ 252 ep = find_ep (gadget, "ep3-bulk"); 253 if (ep && ep_matches (gadget, ep, desc)) 254 return ep; 255 } else if (USB_ENDPOINT_XFER_BULK == type 256 && (USB_DIR_IN & desc->bEndpointAddress)) { 257 /* DMA may be available */ 258 ep = find_ep (gadget, "ep2-bulk"); 259 if (ep && ep_matches (gadget, ep, desc)) 260 return ep; 261 } 262 263 } else if (gadget_is_sh (gadget) && USB_ENDPOINT_XFER_INT == type) { 264 /* single buffering is enough; maybe 8 byte fifo is too */ 265 ep = find_ep (gadget, "ep3in-bulk"); 266 if (ep && ep_matches (gadget, ep, desc)) 267 return ep; 268 269 } else if (gadget_is_mq11xx (gadget) && USB_ENDPOINT_XFER_INT == type) { 270 ep = find_ep (gadget, "ep1-bulk"); 271 if (ep && ep_matches (gadget, ep, desc)) 272 return ep; 273 } 274 275 /* Second, look at endpoints until an unclaimed one looks usable */ 276 list_for_each_entry (ep, &gadget->ep_list, ep_list) { 277 if (ep_matches (gadget, ep, desc)) 278 return ep; 279 } 280 281 /* Fail */ 282 return NULL; 283 } 284 285 /** 286 * usb_ep_autoconfig_reset - reset endpoint autoconfig state 287 * @gadget: device for which autoconfig state will be reset 288 * 289 * Use this for devices where one configuration may need to assign 290 * endpoint resources very differently from the next one. It clears 291 * state such as ep->driver_data and the record of assigned endpoints 292 * used by usb_ep_autoconfig(). 293 */ 294 void usb_ep_autoconfig_reset (struct usb_gadget *gadget) 295 { 296 struct usb_ep *ep; 297 298 list_for_each_entry (ep, &gadget->ep_list, ep_list) { 299 ep->driver_data = NULL; 300 } 301 #ifdef MANY_ENDPOINTS 302 in_epnum = 0; 303 #endif 304 epnum = 0; 305 } 306 307