1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * I/O Processor (IOP) ADB Driver 4 * Written and (C) 1999 by Joshua M. Thompson (funaho@jurai.org) 5 * Based on via-cuda.c by Paul Mackerras. 6 * 7 * 1999-07-01 (jmt) - First implementation for new driver architecture. 8 * 9 * 1999-07-31 (jmt) - First working version. 10 * 11 * TODO: 12 * 13 * o Implement SRQ handling. 14 */ 15 16 #include <linux/types.h> 17 #include <linux/kernel.h> 18 #include <linux/mm.h> 19 #include <linux/delay.h> 20 #include <linux/init.h> 21 #include <linux/proc_fs.h> 22 23 #include <asm/macintosh.h> 24 #include <asm/macints.h> 25 #include <asm/mac_iop.h> 26 #include <asm/mac_oss.h> 27 #include <asm/adb_iop.h> 28 29 #include <linux/adb.h> 30 31 /*#define DEBUG_ADB_IOP*/ 32 33 static struct adb_request *current_req; 34 static struct adb_request *last_req; 35 #if 0 36 static unsigned char reply_buff[16]; 37 static unsigned char *reply_ptr; 38 #endif 39 40 static enum adb_iop_state { 41 idle, 42 sending, 43 awaiting_reply 44 } adb_iop_state; 45 46 static void adb_iop_start(void); 47 static int adb_iop_probe(void); 48 static int adb_iop_init(void); 49 static int adb_iop_send_request(struct adb_request *, int); 50 static int adb_iop_write(struct adb_request *); 51 static int adb_iop_autopoll(int); 52 static void adb_iop_poll(void); 53 static int adb_iop_reset_bus(void); 54 55 struct adb_driver adb_iop_driver = { 56 "ISM IOP", 57 adb_iop_probe, 58 adb_iop_init, 59 adb_iop_send_request, 60 adb_iop_autopoll, 61 adb_iop_poll, 62 adb_iop_reset_bus 63 }; 64 65 static void adb_iop_end_req(struct adb_request *req, int state) 66 { 67 req->complete = 1; 68 current_req = req->next; 69 if (req->done) (*req->done)(req); 70 adb_iop_state = state; 71 } 72 73 /* 74 * Completion routine for ADB commands sent to the IOP. 75 * 76 * This will be called when a packet has been successfully sent. 77 */ 78 79 static void adb_iop_complete(struct iop_msg *msg) 80 { 81 struct adb_request *req; 82 unsigned long flags; 83 84 local_irq_save(flags); 85 86 req = current_req; 87 if ((adb_iop_state == sending) && req && req->reply_expected) { 88 adb_iop_state = awaiting_reply; 89 } 90 91 local_irq_restore(flags); 92 } 93 94 /* 95 * Listen for ADB messages from the IOP. 96 * 97 * This will be called when unsolicited messages (usually replies to TALK 98 * commands or autopoll packets) are received. 99 */ 100 101 static void adb_iop_listen(struct iop_msg *msg) 102 { 103 struct adb_iopmsg *amsg = (struct adb_iopmsg *) msg->message; 104 struct adb_request *req; 105 unsigned long flags; 106 #ifdef DEBUG_ADB_IOP 107 int i; 108 #endif 109 110 local_irq_save(flags); 111 112 req = current_req; 113 114 #ifdef DEBUG_ADB_IOP 115 printk("adb_iop_listen %p: rcvd packet, %d bytes: %02X %02X", req, 116 (uint) amsg->count + 2, (uint) amsg->flags, (uint) amsg->cmd); 117 for (i = 0; i < amsg->count; i++) 118 printk(" %02X", (uint) amsg->data[i]); 119 printk("\n"); 120 #endif 121 122 /* Handle a timeout. Timeout packets seem to occur even after */ 123 /* we've gotten a valid reply to a TALK, so I'm assuming that */ 124 /* a "timeout" is actually more like an "end-of-data" signal. */ 125 /* We need to send back a timeout packet to the IOP to shut */ 126 /* it up, plus complete the current request, if any. */ 127 128 if (amsg->flags & ADB_IOP_TIMEOUT) { 129 msg->reply[0] = ADB_IOP_TIMEOUT | ADB_IOP_AUTOPOLL; 130 msg->reply[1] = 0; 131 msg->reply[2] = 0; 132 if (req && (adb_iop_state != idle)) { 133 adb_iop_end_req(req, idle); 134 } 135 } else { 136 /* TODO: is it possible for more than one chunk of data */ 137 /* to arrive before the timeout? If so we need to */ 138 /* use reply_ptr here like the other drivers do. */ 139 if ((adb_iop_state == awaiting_reply) && 140 (amsg->flags & ADB_IOP_EXPLICIT)) { 141 req->reply_len = amsg->count + 1; 142 memcpy(req->reply, &amsg->cmd, req->reply_len); 143 } else { 144 adb_input(&amsg->cmd, amsg->count + 1, 145 amsg->flags & ADB_IOP_AUTOPOLL); 146 } 147 memcpy(msg->reply, msg->message, IOP_MSG_LEN); 148 } 149 iop_complete_message(msg); 150 local_irq_restore(flags); 151 } 152 153 /* 154 * Start sending an ADB packet, IOP style 155 * 156 * There isn't much to do other than hand the packet over to the IOP 157 * after encapsulating it in an adb_iopmsg. 158 */ 159 160 static void adb_iop_start(void) 161 { 162 unsigned long flags; 163 struct adb_request *req; 164 struct adb_iopmsg amsg; 165 #ifdef DEBUG_ADB_IOP 166 int i; 167 #endif 168 169 /* get the packet to send */ 170 req = current_req; 171 if (!req) return; 172 173 local_irq_save(flags); 174 175 #ifdef DEBUG_ADB_IOP 176 printk("adb_iop_start %p: sending packet, %d bytes:", req, req->nbytes); 177 for (i = 0 ; i < req->nbytes ; i++) 178 printk(" %02X", (uint) req->data[i]); 179 printk("\n"); 180 #endif 181 182 /* The IOP takes MacII-style packets, so */ 183 /* strip the initial ADB_PACKET byte. */ 184 185 amsg.flags = ADB_IOP_EXPLICIT; 186 amsg.count = req->nbytes - 2; 187 188 /* amsg.data immediately follows amsg.cmd, effectively making */ 189 /* amsg.cmd a pointer to the beginning of a full ADB packet. */ 190 memcpy(&amsg.cmd, req->data + 1, req->nbytes - 1); 191 192 req->sent = 1; 193 adb_iop_state = sending; 194 local_irq_restore(flags); 195 196 /* Now send it. The IOP manager will call adb_iop_complete */ 197 /* when the packet has been sent. */ 198 199 iop_send_message(ADB_IOP, ADB_CHAN, req, 200 sizeof(amsg), (__u8 *) &amsg, adb_iop_complete); 201 } 202 203 int adb_iop_probe(void) 204 { 205 if (!iop_ism_present) return -ENODEV; 206 return 0; 207 } 208 209 int adb_iop_init(void) 210 { 211 printk("adb: IOP ISM driver v0.4 for Unified ADB.\n"); 212 iop_listen(ADB_IOP, ADB_CHAN, adb_iop_listen, "ADB"); 213 return 0; 214 } 215 216 int adb_iop_send_request(struct adb_request *req, int sync) 217 { 218 int err; 219 220 err = adb_iop_write(req); 221 if (err) return err; 222 223 if (sync) { 224 while (!req->complete) adb_iop_poll(); 225 } 226 return 0; 227 } 228 229 static int adb_iop_write(struct adb_request *req) 230 { 231 unsigned long flags; 232 233 if ((req->nbytes < 2) || (req->data[0] != ADB_PACKET)) { 234 req->complete = 1; 235 return -EINVAL; 236 } 237 238 local_irq_save(flags); 239 240 req->next = NULL; 241 req->sent = 0; 242 req->complete = 0; 243 req->reply_len = 0; 244 245 if (current_req != 0) { 246 last_req->next = req; 247 last_req = req; 248 } else { 249 current_req = req; 250 last_req = req; 251 } 252 253 local_irq_restore(flags); 254 if (adb_iop_state == idle) adb_iop_start(); 255 return 0; 256 } 257 258 int adb_iop_autopoll(int devs) 259 { 260 /* TODO: how do we enable/disable autopoll? */ 261 return 0; 262 } 263 264 void adb_iop_poll(void) 265 { 266 if (adb_iop_state == idle) adb_iop_start(); 267 iop_ism_irq_poll(ADB_IOP); 268 } 269 270 int adb_iop_reset_bus(void) 271 { 272 struct adb_request req = { 273 .reply_expected = 0, 274 .nbytes = 2, 275 .data = { ADB_PACKET, 0 }, 276 }; 277 278 adb_iop_write(&req); 279 while (!req.complete) { 280 adb_iop_poll(); 281 schedule(); 282 } 283 284 return 0; 285 } 286