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 <usbdescriptors.h> 27 #include <asm/errno.h> 28 #include <linux/usb/gadget.h> 29 #include <asm/unaligned.h> 30 #include "gadget_chips.h" 31 32 #define isdigit(c) ('0' <= (c) && (c) <= '9') 33 34 /* we must assign addresses for configurable endpoints (like net2280) */ 35 static unsigned epnum; 36 37 /* #define MANY_ENDPOINTS */ 38 #ifdef MANY_ENDPOINTS 39 /* more than 15 configurable endpoints */ 40 static unsigned in_epnum; 41 #endif 42 43 44 /* 45 * This should work with endpoints from controller drivers sharing the 46 * same endpoint naming convention. By example: 47 * 48 * - ep1, ep2, ... address is fixed, not direction or type 49 * - ep1in, ep2out, ... address and direction are fixed, not type 50 * - ep1-bulk, ep2-bulk, ... address and type are fixed, not direction 51 * - ep1in-bulk, ep2out-iso, ... all three are fixed 52 * - ep-* ... no functionality restrictions 53 * 54 * Type suffixes are "-bulk", "-iso", or "-int". Numbers are decimal. 55 * Less common restrictions are implied by gadget_is_*(). 56 * 57 * NOTE: each endpoint is unidirectional, as specified by its USB 58 * descriptor; and isn't specific to a configuration or altsetting. 59 */ 60 static int ep_matches( 61 struct usb_gadget *gadget, 62 struct usb_ep *ep, 63 struct usb_endpoint_descriptor *desc 64 ) 65 { 66 u8 type; 67 const char *tmp; 68 u16 max; 69 70 /* endpoint already claimed? */ 71 if (NULL != ep->driver_data) 72 return 0; 73 74 /* only support ep0 for portable CONTROL traffic */ 75 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; 76 if (USB_ENDPOINT_XFER_CONTROL == type) 77 return 0; 78 79 /* some other naming convention */ 80 if ('e' != ep->name[0]) 81 return 0; 82 83 /* type-restriction: "-iso", "-bulk", or "-int". 84 * direction-restriction: "in", "out". 85 */ 86 if ('-' != ep->name[2]) { 87 tmp = strrchr(ep->name, '-'); 88 if (tmp) { 89 switch (type) { 90 case USB_ENDPOINT_XFER_INT: 91 /* bulk endpoints handle interrupt transfers, 92 * except the toggle-quirky iso-synch kind 93 */ 94 if ('s' == tmp[2]) /* == "-iso" */ 95 return 0; 96 /* for now, avoid PXA "interrupt-in"; 97 * it's documented as never using DATA1. 98 */ 99 if (gadget_is_pxa(gadget) 100 && 'i' == tmp[1]) 101 return 0; 102 break; 103 case USB_ENDPOINT_XFER_BULK: 104 if ('b' != tmp[1]) /* != "-bulk" */ 105 return 0; 106 break; 107 case USB_ENDPOINT_XFER_ISOC: 108 if ('s' != tmp[2]) /* != "-iso" */ 109 return 0; 110 } 111 } else { 112 tmp = ep->name + strlen(ep->name); 113 } 114 115 /* direction-restriction: "..in-..", "out-.." */ 116 tmp--; 117 if (!isdigit(*tmp)) { 118 if (desc->bEndpointAddress & USB_DIR_IN) { 119 if ('n' != *tmp) 120 return 0; 121 } else { 122 if ('t' != *tmp) 123 return 0; 124 } 125 } 126 } 127 128 /* endpoint maxpacket size is an input parameter, except for bulk 129 * where it's an output parameter representing the full speed limit. 130 * the usb spec fixes high speed bulk maxpacket at 512 bytes. 131 */ 132 max = 0x7ff & le16_to_cpu(get_unaligned(&desc->wMaxPacketSize)); 133 switch (type) { 134 case USB_ENDPOINT_XFER_INT: 135 /* INT: limit 64 bytes full speed, 1024 high speed */ 136 if (!gadget->is_dualspeed && max > 64) 137 return 0; 138 /* FALLTHROUGH */ 139 140 case USB_ENDPOINT_XFER_ISOC: 141 /* ISO: limit 1023 bytes full speed, 1024 high speed */ 142 if (ep->maxpacket < max) 143 return 0; 144 if (!gadget->is_dualspeed && max > 1023) 145 return 0; 146 147 /* BOTH: "high bandwidth" works only at high speed */ 148 if ((get_unaligned(&desc->wMaxPacketSize) & 149 __constant_cpu_to_le16(3<<11))) { 150 if (!gadget->is_dualspeed) 151 return 0; 152 /* configure your hardware with enough buffering!! */ 153 } 154 break; 155 } 156 157 /* MATCH!! */ 158 159 /* report address */ 160 if (isdigit(ep->name[2])) { 161 u8 num = simple_strtoul(&ep->name[2], NULL, 10); 162 desc->bEndpointAddress |= num; 163 #ifdef MANY_ENDPOINTS 164 } else if (desc->bEndpointAddress & USB_DIR_IN) { 165 if (++in_epnum > 15) 166 return 0; 167 desc->bEndpointAddress = USB_DIR_IN | in_epnum; 168 #endif 169 } else { 170 if (++epnum > 15) 171 return 0; 172 desc->bEndpointAddress |= epnum; 173 } 174 175 /* report (variable) full speed bulk maxpacket */ 176 if (USB_ENDPOINT_XFER_BULK == type) { 177 int size = ep->maxpacket; 178 179 /* min() doesn't work on bitfields with gcc-3.5 */ 180 if (size > 64) 181 size = 64; 182 put_unaligned(cpu_to_le16(size), &desc->wMaxPacketSize); 183 } 184 return 1; 185 } 186 187 static struct usb_ep * 188 find_ep(struct usb_gadget *gadget, const char *name) 189 { 190 struct usb_ep *ep; 191 192 list_for_each_entry(ep, &gadget->ep_list, ep_list) { 193 if (0 == strcmp(ep->name, name)) 194 return ep; 195 } 196 return NULL; 197 } 198 199 /** 200 * usb_ep_autoconfig - choose an endpoint matching the descriptor 201 * @gadget: The device to which the endpoint must belong. 202 * @desc: Endpoint descriptor, with endpoint direction and transfer mode 203 * initialized. For periodic transfers, the maximum packet 204 * size must also be initialized. This is modified on success. 205 * 206 * By choosing an endpoint to use with the specified descriptor, this 207 * routine simplifies writing gadget drivers that work with multiple 208 * USB device controllers. The endpoint would be passed later to 209 * usb_ep_enable(), along with some descriptor. 210 * 211 * That second descriptor won't always be the same as the first one. 212 * For example, isochronous endpoints can be autoconfigured for high 213 * bandwidth, and then used in several lower bandwidth altsettings. 214 * Also, high and full speed descriptors will be different. 215 * 216 * Be sure to examine and test the results of autoconfiguration on your 217 * hardware. This code may not make the best choices about how to use the 218 * USB controller, and it can't know all the restrictions that may apply. 219 * Some combinations of driver and hardware won't be able to autoconfigure. 220 * 221 * On success, this returns an un-claimed usb_ep, and modifies the endpoint 222 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value 223 * is initialized as if the endpoint were used at full speed. To prevent 224 * the endpoint from being returned by a later autoconfig call, claim it 225 * by assigning ep->driver_data to some non-null value. 226 * 227 * On failure, this returns a null endpoint descriptor. 228 */ 229 struct usb_ep *usb_ep_autoconfig( 230 struct usb_gadget *gadget, 231 struct usb_endpoint_descriptor *desc 232 ) 233 { 234 struct usb_ep *ep; 235 u8 type; 236 237 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; 238 239 /* First, apply chip-specific "best usage" knowledge. 240 * This might make a good usb_gadget_ops hook ... 241 */ 242 if (gadget_is_net2280(gadget) && type == USB_ENDPOINT_XFER_INT) { 243 /* ep-e, ep-f are PIO with only 64 byte fifos */ 244 ep = find_ep(gadget, "ep-e"); 245 if (ep && ep_matches(gadget, ep, desc)) 246 return ep; 247 ep = find_ep(gadget, "ep-f"); 248 if (ep && ep_matches(gadget, ep, desc)) 249 return ep; 250 251 } else if (gadget_is_goku(gadget)) { 252 if (USB_ENDPOINT_XFER_INT == type) { 253 /* single buffering is enough */ 254 ep = find_ep(gadget, "ep3-bulk"); 255 if (ep && ep_matches(gadget, ep, desc)) 256 return ep; 257 } else if (USB_ENDPOINT_XFER_BULK == type 258 && (USB_DIR_IN & desc->bEndpointAddress)) { 259 /* DMA may be available */ 260 ep = find_ep(gadget, "ep2-bulk"); 261 if (ep && ep_matches(gadget, ep, desc)) 262 return ep; 263 } 264 265 } else if (gadget_is_sh(gadget) && USB_ENDPOINT_XFER_INT == type) { 266 /* single buffering is enough; maybe 8 byte fifo is too */ 267 ep = find_ep(gadget, "ep3in-bulk"); 268 if (ep && ep_matches(gadget, ep, desc)) 269 return ep; 270 271 } else if (gadget_is_mq11xx(gadget) && USB_ENDPOINT_XFER_INT == type) { 272 ep = find_ep(gadget, "ep1-bulk"); 273 if (ep && ep_matches(gadget, ep, desc)) 274 return ep; 275 } 276 277 /* Second, look at endpoints until an unclaimed one looks usable */ 278 list_for_each_entry(ep, &gadget->ep_list, ep_list) { 279 if (ep_matches(gadget, ep, desc)) 280 return ep; 281 } 282 283 /* Fail */ 284 return NULL; 285 } 286 287 /** 288 * usb_ep_autoconfig_reset - reset endpoint autoconfig state 289 * @gadget: device for which autoconfig state will be reset 290 * 291 * Use this for devices where one configuration may need to assign 292 * endpoint resources very differently from the next one. It clears 293 * state such as ep->driver_data and the record of assigned endpoints 294 * used by usb_ep_autoconfig(). 295 */ 296 void usb_ep_autoconfig_reset(struct usb_gadget *gadget) 297 { 298 struct usb_ep *ep; 299 300 list_for_each_entry(ep, &gadget->ep_list, ep_list) { 301 ep->driver_data = NULL; 302 } 303 #ifdef MANY_ENDPOINTS 304 in_epnum = 0; 305 #endif 306 epnum = 0; 307 } 308