1 /*
2 * I/O Processor (IOP) ADB Driver
3 * Written and (C) 1999 by Joshua M. Thompson (funaho@jurai.org)
4 * Based on via-cuda.c by Paul Mackerras.
5 *
6 * 1999-07-01 (jmt) - First implementation for new driver architecture.
7 *
8 * 1999-07-31 (jmt) - First working version.
9 *
10 * TODO:
11 *
12 * o Implement SRQ handling.
13 */
14
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/mm.h>
18 #include <linux/delay.h>
19 #include <linux/init.h>
20 #include <linux/proc_fs.h>
21
22 #include <asm/bootinfo.h>
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 extern void iop_ism_irq(int, void *, struct pt_regs *);
34
35 static struct adb_request *current_req;
36 static struct adb_request *last_req;
37 #if 0
38 static unsigned char reply_buff[16];
39 static unsigned char *reply_ptr;
40 #endif
41
42 static enum adb_iop_state {
43 idle,
44 sending,
45 awaiting_reply
46 } adb_iop_state;
47
48 static void adb_iop_start(void);
49 static int adb_iop_probe(void);
50 static int adb_iop_init(void);
51 static int adb_iop_send_request(struct adb_request *, int);
52 static int adb_iop_write(struct adb_request *);
53 static int adb_iop_autopoll(int);
54 static void adb_iop_poll(void);
55 static int adb_iop_reset_bus(void);
56
57 struct adb_driver adb_iop_driver = {
58 "ISM IOP",
59 adb_iop_probe,
60 adb_iop_init,
61 adb_iop_send_request,
62 adb_iop_autopoll,
63 adb_iop_poll,
64 adb_iop_reset_bus
65 };
66
adb_iop_end_req(struct adb_request * req,int state)67 static void adb_iop_end_req(struct adb_request *req, int state)
68 {
69 req->complete = 1;
70 current_req = req->next;
71 if (req->done) (*req->done)(req);
72 adb_iop_state = state;
73 }
74
75 /*
76 * Completion routine for ADB commands sent to the IOP.
77 *
78 * This will be called when a packet has been successfully sent.
79 */
80
adb_iop_complete(struct iop_msg * msg,struct pt_regs * regs)81 static void adb_iop_complete(struct iop_msg *msg, struct pt_regs *regs)
82 {
83 struct adb_request *req;
84 uint flags;
85
86 save_flags(flags);
87 cli();
88
89 req = current_req;
90 if ((adb_iop_state == sending) && req && req->reply_expected) {
91 adb_iop_state = awaiting_reply;
92 }
93
94 restore_flags(flags);
95 }
96
97 /*
98 * Listen for ADB messages from the IOP.
99 *
100 * This will be called when unsolicited messages (usually replies to TALK
101 * commands or autopoll packets) are received.
102 */
103
adb_iop_listen(struct iop_msg * msg,struct pt_regs * regs)104 static void adb_iop_listen(struct iop_msg *msg, struct pt_regs *regs)
105 {
106 struct adb_iopmsg *amsg = (struct adb_iopmsg *) msg->message;
107 struct adb_request *req;
108 uint flags;
109 #ifdef DEBUG_ADB_IOP
110 int i;
111 #endif
112
113 save_flags(flags);
114 cli();
115
116 req = current_req;
117
118 #ifdef DEBUG_ADB_IOP
119 printk("adb_iop_listen %p: rcvd packet, %d bytes: %02X %02X", req,
120 (uint) amsg->count + 2, (uint) amsg->flags, (uint) amsg->cmd);
121 for (i = 0; i < amsg->count; i++)
122 printk(" %02X", (uint) amsg->data[i]);
123 printk("\n");
124 #endif
125
126 /* Handle a timeout. Timeout packets seem to occur even after */
127 /* we've gotten a valid reply to a TALK, so I'm assuming that */
128 /* a "timeout" is actually more like an "end-of-data" signal. */
129 /* We need to send back a timeout packet to the IOP to shut */
130 /* it up, plus complete the current request, if any. */
131
132 if (amsg->flags & ADB_IOP_TIMEOUT) {
133 msg->reply[0] = ADB_IOP_TIMEOUT | ADB_IOP_AUTOPOLL;
134 msg->reply[1] = 0;
135 msg->reply[2] = 0;
136 if (req && (adb_iop_state != idle)) {
137 adb_iop_end_req(req, idle);
138 }
139 } else {
140 /* TODO: is it possible for more than one chunk of data */
141 /* to arrive before the timeout? If so we need to */
142 /* use reply_ptr here like the other drivers do. */
143 if ((adb_iop_state == awaiting_reply) &&
144 (amsg->flags & ADB_IOP_EXPLICIT)) {
145 req->reply_len = amsg->count + 1;
146 memcpy(req->reply, &amsg->cmd, req->reply_len);
147 } else {
148 adb_input(&amsg->cmd, amsg->count + 1, regs,
149 amsg->flags & ADB_IOP_AUTOPOLL);
150 }
151 memcpy(msg->reply, msg->message, IOP_MSG_LEN);
152 }
153 iop_complete_message(msg);
154 restore_flags(flags);
155 }
156
157 /*
158 * Start sending an ADB packet, IOP style
159 *
160 * There isn't much to do other than hand the packet over to the IOP
161 * after encapsulating it in an adb_iopmsg.
162 */
163
adb_iop_start(void)164 static void adb_iop_start(void)
165 {
166 unsigned long flags;
167 struct adb_request *req;
168 struct adb_iopmsg amsg;
169 #ifdef DEBUG_ADB_IOP
170 int i;
171 #endif
172
173 /* get the packet to send */
174 req = current_req;
175 if (!req) return;
176
177 save_flags(flags);
178 cli();
179
180 #ifdef DEBUG_ADB_IOP
181 printk("adb_iop_start %p: sending packet, %d bytes:", req, req->nbytes);
182 for (i = 0 ; i < req->nbytes ; i++)
183 printk(" %02X", (uint) req->data[i]);
184 printk("\n");
185 #endif
186
187 /* The IOP takes MacII-style packets, so */
188 /* strip the initial ADB_PACKET byte. */
189
190 amsg.flags = ADB_IOP_EXPLICIT;
191 amsg.count = req->nbytes - 2;
192
193 /* amsg.data immediately follows amsg.cmd, effectively making */
194 /* amsg.cmd a pointer to the beginning of a full ADB packet. */
195 memcpy(&amsg.cmd, req->data + 1, req->nbytes - 1);
196
197 req->sent = 1;
198 adb_iop_state = sending;
199 restore_flags(flags);
200
201 /* Now send it. The IOP manager will call adb_iop_complete */
202 /* when the packet has been sent. */
203
204 iop_send_message(ADB_IOP, ADB_CHAN, req,
205 sizeof(amsg), (__u8 *) &amsg, adb_iop_complete);
206 }
207
adb_iop_probe(void)208 int adb_iop_probe(void)
209 {
210 if (!iop_ism_present) return -ENODEV;
211 return 0;
212 }
213
adb_iop_init(void)214 int adb_iop_init(void)
215 {
216 printk("adb: IOP ISM driver v0.4 for Unified ADB.\n");
217 iop_listen(ADB_IOP, ADB_CHAN, adb_iop_listen, "ADB");
218 return 0;
219 }
220
adb_iop_send_request(struct adb_request * req,int sync)221 int adb_iop_send_request(struct adb_request *req, int sync)
222 {
223 int err;
224
225 err = adb_iop_write(req);
226 if (err) return err;
227
228 if (sync) {
229 while (!req->complete) adb_iop_poll();
230 }
231 return 0;
232 }
233
adb_iop_write(struct adb_request * req)234 static int adb_iop_write(struct adb_request *req)
235 {
236 unsigned long flags;
237
238 if ((req->nbytes < 2) || (req->data[0] != ADB_PACKET)) {
239 req->complete = 1;
240 return -EINVAL;
241 }
242
243 save_flags(flags);
244 cli();
245
246 req->next = 0;
247 req->sent = 0;
248 req->complete = 0;
249 req->reply_len = 0;
250
251 if (current_req != 0) {
252 last_req->next = req;
253 last_req = req;
254 } else {
255 current_req = req;
256 last_req = req;
257 }
258
259 restore_flags(flags);
260 if (adb_iop_state == idle) adb_iop_start();
261 return 0;
262 }
263
adb_iop_autopoll(int devs)264 int adb_iop_autopoll(int devs)
265 {
266 /* TODO: how do we enable/disable autopoll? */
267 return 0;
268 }
269
adb_iop_poll(void)270 void adb_iop_poll(void)
271 {
272 if (adb_iop_state == idle) adb_iop_start();
273 iop_ism_irq(0, (void *) ADB_IOP, NULL);
274 }
275
adb_iop_reset_bus(void)276 int adb_iop_reset_bus(void)
277 {
278 struct adb_request req = {
279 .reply_expected = 0,
280 .nbytes = 2,
281 .data = { ADB_PACKET, 0 },
282 };
283
284 adb_iop_write(&req);
285 while (!req.complete) {
286 adb_iop_poll();
287 schedule();
288 }
289
290 return 0;
291 }
292