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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for the ADB controller in the Mac I/O (Hydra) chip.
4 */
5#include <linux/types.h>
6#include <linux/errno.h>
7#include <linux/kernel.h>
8#include <linux/delay.h>
9#include <linux/spinlock.h>
10#include <linux/interrupt.h>
11#include <linux/pgtable.h>
12#include <linux/of.h>
13#include <linux/of_address.h>
14#include <linux/of_irq.h>
15#include <linux/adb.h>
16
17#include <asm/io.h>
18#include <asm/hydra.h>
19#include <asm/irq.h>
20#include <linux/init.h>
21#include <linux/ioport.h>
22
23struct preg {
24 unsigned char r;
25 char pad[15];
26};
27
28struct adb_regs {
29 struct preg intr;
30 struct preg data[9];
31 struct preg intr_enb;
32 struct preg dcount;
33 struct preg error;
34 struct preg ctrl;
35 struct preg autopoll;
36 struct preg active_hi;
37 struct preg active_lo;
38 struct preg test;
39};
40
41/* Bits in intr and intr_enb registers */
42#define DFB 1 /* data from bus */
43#define TAG 2 /* transfer access grant */
44
45/* Bits in dcount register */
46#define HMB 0x0f /* how many bytes */
47#define APD 0x10 /* auto-poll data */
48
49/* Bits in error register */
50#define NRE 1 /* no response error */
51#define DLE 2 /* data lost error */
52
53/* Bits in ctrl register */
54#define TAR 1 /* transfer access request */
55#define DTB 2 /* data to bus */
56#define CRE 4 /* command response expected */
57#define ADB_RST 8 /* ADB reset */
58
59/* Bits in autopoll register */
60#define APE 1 /* autopoll enable */
61
62static volatile struct adb_regs __iomem *adb;
63static struct adb_request *current_req, *last_req;
64static DEFINE_SPINLOCK(macio_lock);
65
66static int macio_probe(void);
67static int macio_init(void);
68static irqreturn_t macio_adb_interrupt(int irq, void *arg);
69static int macio_send_request(struct adb_request *req, int sync);
70static int macio_adb_autopoll(int devs);
71static void macio_adb_poll(void);
72static int macio_adb_reset_bus(void);
73
74struct adb_driver macio_adb_driver = {
75 .name = "MACIO",
76 .probe = macio_probe,
77 .init = macio_init,
78 .send_request = macio_send_request,
79 .autopoll = macio_adb_autopoll,
80 .poll = macio_adb_poll,
81 .reset_bus = macio_adb_reset_bus,
82};
83
84int macio_probe(void)
85{
86 struct device_node *np;
87
88 np = of_find_compatible_node(NULL, "adb", "chrp,adb0");
89 if (np) {
90 of_node_put(np);
91 return 0;
92 }
93 return -ENODEV;
94}
95
96int macio_init(void)
97{
98 struct device_node *adbs;
99 struct resource r;
100 unsigned int irq;
101
102 adbs = of_find_compatible_node(NULL, "adb", "chrp,adb0");
103 if (!adbs)
104 return -ENXIO;
105
106 if (of_address_to_resource(adbs, 0, &r)) {
107 of_node_put(adbs);
108 return -ENXIO;
109 }
110 adb = ioremap(r.start, sizeof(struct adb_regs));
111 if (!adb) {
112 of_node_put(adbs);
113 return -ENOMEM;
114 }
115
116 out_8(&adb->ctrl.r, 0);
117 out_8(&adb->intr.r, 0);
118 out_8(&adb->error.r, 0);
119 out_8(&adb->active_hi.r, 0xff); /* for now, set all devices active */
120 out_8(&adb->active_lo.r, 0xff);
121 out_8(&adb->autopoll.r, APE);
122
123 irq = irq_of_parse_and_map(adbs, 0);
124 of_node_put(adbs);
125 if (request_irq(irq, macio_adb_interrupt, 0, "ADB", (void *)0)) {
126 iounmap(adb);
127 printk(KERN_ERR "ADB: can't get irq %d\n", irq);
128 return -EAGAIN;
129 }
130 out_8(&adb->intr_enb.r, DFB | TAG);
131
132 printk("adb: mac-io driver 1.0 for unified ADB\n");
133
134 return 0;
135}
136
137static int macio_adb_autopoll(int devs)
138{
139 unsigned long flags;
140
141 spin_lock_irqsave(&macio_lock, flags);
142 out_8(&adb->active_hi.r, devs >> 8);
143 out_8(&adb->active_lo.r, devs);
144 out_8(&adb->autopoll.r, devs? APE: 0);
145 spin_unlock_irqrestore(&macio_lock, flags);
146 return 0;
147}
148
149static int macio_adb_reset_bus(void)
150{
151 unsigned long flags;
152 int timeout = 1000000;
153
154 /* Hrm... we may want to not lock interrupts for so
155 * long ... oh well, who uses that chip anyway ? :)
156 * That function will be seldom used during boot
157 * on rare machines, so...
158 */
159 spin_lock_irqsave(&macio_lock, flags);
160 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | ADB_RST);
161 while ((in_8(&adb->ctrl.r) & ADB_RST) != 0) {
162 if (--timeout == 0) {
163 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) & ~ADB_RST);
164 spin_unlock_irqrestore(&macio_lock, flags);
165 return -1;
166 }
167 }
168 spin_unlock_irqrestore(&macio_lock, flags);
169 return 0;
170}
171
172/* Send an ADB command */
173static int macio_send_request(struct adb_request *req, int sync)
174{
175 unsigned long flags;
176 int i;
177
178 if (req->data[0] != ADB_PACKET)
179 return -EINVAL;
180
181 for (i = 0; i < req->nbytes - 1; ++i)
182 req->data[i] = req->data[i+1];
183 --req->nbytes;
184
185 req->next = NULL;
186 req->sent = 0;
187 req->complete = 0;
188 req->reply_len = 0;
189
190 spin_lock_irqsave(&macio_lock, flags);
191 if (current_req) {
192 last_req->next = req;
193 last_req = req;
194 } else {
195 current_req = last_req = req;
196 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
197 }
198 spin_unlock_irqrestore(&macio_lock, flags);
199
200 if (sync) {
201 while (!req->complete)
202 macio_adb_poll();
203 }
204
205 return 0;
206}
207
208static irqreturn_t macio_adb_interrupt(int irq, void *arg)
209{
210 int i, n, err;
211 struct adb_request *req = NULL;
212 unsigned char ibuf[16];
213 int ibuf_len = 0;
214 int complete = 0;
215 int autopoll = 0;
216 int handled = 0;
217
218 spin_lock(&macio_lock);
219 if (in_8(&adb->intr.r) & TAG) {
220 handled = 1;
221 req = current_req;
222 if (req) {
223 /* put the current request in */
224 for (i = 0; i < req->nbytes; ++i)
225 out_8(&adb->data[i].r, req->data[i]);
226 out_8(&adb->dcount.r, req->nbytes & HMB);
227 req->sent = 1;
228 if (req->reply_expected) {
229 out_8(&adb->ctrl.r, DTB + CRE);
230 } else {
231 out_8(&adb->ctrl.r, DTB);
232 current_req = req->next;
233 complete = 1;
234 if (current_req)
235 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
236 }
237 }
238 out_8(&adb->intr.r, 0);
239 }
240
241 if (in_8(&adb->intr.r) & DFB) {
242 handled = 1;
243 err = in_8(&adb->error.r);
244 if (current_req && current_req->sent) {
245 /* this is the response to a command */
246 req = current_req;
247 if (err == 0) {
248 req->reply_len = in_8(&adb->dcount.r) & HMB;
249 for (i = 0; i < req->reply_len; ++i)
250 req->reply[i] = in_8(&adb->data[i].r);
251 }
252 current_req = req->next;
253 complete = 1;
254 if (current_req)
255 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
256 } else if (err == 0) {
257 /* autopoll data */
258 n = in_8(&adb->dcount.r) & HMB;
259 for (i = 0; i < n; ++i)
260 ibuf[i] = in_8(&adb->data[i].r);
261 ibuf_len = n;
262 autopoll = (in_8(&adb->dcount.r) & APD) != 0;
263 }
264 out_8(&adb->error.r, 0);
265 out_8(&adb->intr.r, 0);
266 }
267 spin_unlock(&macio_lock);
268 if (complete && req) {
269 void (*done)(struct adb_request *) = req->done;
270 mb();
271 req->complete = 1;
272 /* Here, we assume that if the request has a done member, the
273 * struct request will survive to setting req->complete to 1
274 */
275 if (done)
276 (*done)(req);
277 }
278 if (ibuf_len)
279 adb_input(ibuf, ibuf_len, autopoll);
280
281 return IRQ_RETVAL(handled);
282}
283
284static void macio_adb_poll(void)
285{
286 unsigned long flags;
287
288 local_irq_save(flags);
289 if (in_8(&adb->intr.r) != 0)
290 macio_adb_interrupt(0, NULL);
291 local_irq_restore(flags);
292}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for the ADB controller in the Mac I/O (Hydra) chip.
4 */
5#include <stdarg.h>
6#include <linux/types.h>
7#include <linux/errno.h>
8#include <linux/kernel.h>
9#include <linux/delay.h>
10#include <linux/spinlock.h>
11#include <linux/interrupt.h>
12#include <asm/prom.h>
13#include <linux/adb.h>
14#include <asm/io.h>
15#include <asm/pgtable.h>
16#include <asm/hydra.h>
17#include <asm/irq.h>
18#include <linux/init.h>
19#include <linux/ioport.h>
20
21struct preg {
22 unsigned char r;
23 char pad[15];
24};
25
26struct adb_regs {
27 struct preg intr;
28 struct preg data[9];
29 struct preg intr_enb;
30 struct preg dcount;
31 struct preg error;
32 struct preg ctrl;
33 struct preg autopoll;
34 struct preg active_hi;
35 struct preg active_lo;
36 struct preg test;
37};
38
39/* Bits in intr and intr_enb registers */
40#define DFB 1 /* data from bus */
41#define TAG 2 /* transfer access grant */
42
43/* Bits in dcount register */
44#define HMB 0x0f /* how many bytes */
45#define APD 0x10 /* auto-poll data */
46
47/* Bits in error register */
48#define NRE 1 /* no response error */
49#define DLE 2 /* data lost error */
50
51/* Bits in ctrl register */
52#define TAR 1 /* transfer access request */
53#define DTB 2 /* data to bus */
54#define CRE 4 /* command response expected */
55#define ADB_RST 8 /* ADB reset */
56
57/* Bits in autopoll register */
58#define APE 1 /* autopoll enable */
59
60static volatile struct adb_regs __iomem *adb;
61static struct adb_request *current_req, *last_req;
62static DEFINE_SPINLOCK(macio_lock);
63
64static int macio_probe(void);
65static int macio_init(void);
66static irqreturn_t macio_adb_interrupt(int irq, void *arg);
67static int macio_send_request(struct adb_request *req, int sync);
68static int macio_adb_autopoll(int devs);
69static void macio_adb_poll(void);
70static int macio_adb_reset_bus(void);
71
72struct adb_driver macio_adb_driver = {
73 .name = "MACIO",
74 .probe = macio_probe,
75 .init = macio_init,
76 .send_request = macio_send_request,
77 .autopoll = macio_adb_autopoll,
78 .poll = macio_adb_poll,
79 .reset_bus = macio_adb_reset_bus,
80};
81
82int macio_probe(void)
83{
84 struct device_node *np;
85
86 np = of_find_compatible_node(NULL, "adb", "chrp,adb0");
87 if (np) {
88 of_node_put(np);
89 return 0;
90 }
91 return -ENODEV;
92}
93
94int macio_init(void)
95{
96 struct device_node *adbs;
97 struct resource r;
98 unsigned int irq;
99
100 adbs = of_find_compatible_node(NULL, "adb", "chrp,adb0");
101 if (adbs == 0)
102 return -ENXIO;
103
104 if (of_address_to_resource(adbs, 0, &r)) {
105 of_node_put(adbs);
106 return -ENXIO;
107 }
108 adb = ioremap(r.start, sizeof(struct adb_regs));
109
110 out_8(&adb->ctrl.r, 0);
111 out_8(&adb->intr.r, 0);
112 out_8(&adb->error.r, 0);
113 out_8(&adb->active_hi.r, 0xff); /* for now, set all devices active */
114 out_8(&adb->active_lo.r, 0xff);
115 out_8(&adb->autopoll.r, APE);
116
117 irq = irq_of_parse_and_map(adbs, 0);
118 of_node_put(adbs);
119 if (request_irq(irq, macio_adb_interrupt, 0, "ADB", (void *)0)) {
120 printk(KERN_ERR "ADB: can't get irq %d\n", irq);
121 return -EAGAIN;
122 }
123 out_8(&adb->intr_enb.r, DFB | TAG);
124
125 printk("adb: mac-io driver 1.0 for unified ADB\n");
126
127 return 0;
128}
129
130static int macio_adb_autopoll(int devs)
131{
132 unsigned long flags;
133
134 spin_lock_irqsave(&macio_lock, flags);
135 out_8(&adb->active_hi.r, devs >> 8);
136 out_8(&adb->active_lo.r, devs);
137 out_8(&adb->autopoll.r, devs? APE: 0);
138 spin_unlock_irqrestore(&macio_lock, flags);
139 return 0;
140}
141
142static int macio_adb_reset_bus(void)
143{
144 unsigned long flags;
145 int timeout = 1000000;
146
147 /* Hrm... we may want to not lock interrupts for so
148 * long ... oh well, who uses that chip anyway ? :)
149 * That function will be seldom used during boot
150 * on rare machines, so...
151 */
152 spin_lock_irqsave(&macio_lock, flags);
153 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | ADB_RST);
154 while ((in_8(&adb->ctrl.r) & ADB_RST) != 0) {
155 if (--timeout == 0) {
156 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) & ~ADB_RST);
157 spin_unlock_irqrestore(&macio_lock, flags);
158 return -1;
159 }
160 }
161 spin_unlock_irqrestore(&macio_lock, flags);
162 return 0;
163}
164
165/* Send an ADB command */
166static int macio_send_request(struct adb_request *req, int sync)
167{
168 unsigned long flags;
169 int i;
170
171 if (req->data[0] != ADB_PACKET)
172 return -EINVAL;
173
174 for (i = 0; i < req->nbytes - 1; ++i)
175 req->data[i] = req->data[i+1];
176 --req->nbytes;
177
178 req->next = NULL;
179 req->sent = 0;
180 req->complete = 0;
181 req->reply_len = 0;
182
183 spin_lock_irqsave(&macio_lock, flags);
184 if (current_req != 0) {
185 last_req->next = req;
186 last_req = req;
187 } else {
188 current_req = last_req = req;
189 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
190 }
191 spin_unlock_irqrestore(&macio_lock, flags);
192
193 if (sync) {
194 while (!req->complete)
195 macio_adb_poll();
196 }
197
198 return 0;
199}
200
201static irqreturn_t macio_adb_interrupt(int irq, void *arg)
202{
203 int i, n, err;
204 struct adb_request *req = NULL;
205 unsigned char ibuf[16];
206 int ibuf_len = 0;
207 int complete = 0;
208 int autopoll = 0;
209 int handled = 0;
210
211 spin_lock(&macio_lock);
212 if (in_8(&adb->intr.r) & TAG) {
213 handled = 1;
214 if ((req = current_req) != 0) {
215 /* put the current request in */
216 for (i = 0; i < req->nbytes; ++i)
217 out_8(&adb->data[i].r, req->data[i]);
218 out_8(&adb->dcount.r, req->nbytes & HMB);
219 req->sent = 1;
220 if (req->reply_expected) {
221 out_8(&adb->ctrl.r, DTB + CRE);
222 } else {
223 out_8(&adb->ctrl.r, DTB);
224 current_req = req->next;
225 complete = 1;
226 if (current_req)
227 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
228 }
229 }
230 out_8(&adb->intr.r, 0);
231 }
232
233 if (in_8(&adb->intr.r) & DFB) {
234 handled = 1;
235 err = in_8(&adb->error.r);
236 if (current_req && current_req->sent) {
237 /* this is the response to a command */
238 req = current_req;
239 if (err == 0) {
240 req->reply_len = in_8(&adb->dcount.r) & HMB;
241 for (i = 0; i < req->reply_len; ++i)
242 req->reply[i] = in_8(&adb->data[i].r);
243 }
244 current_req = req->next;
245 complete = 1;
246 if (current_req)
247 out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
248 } else if (err == 0) {
249 /* autopoll data */
250 n = in_8(&adb->dcount.r) & HMB;
251 for (i = 0; i < n; ++i)
252 ibuf[i] = in_8(&adb->data[i].r);
253 ibuf_len = n;
254 autopoll = (in_8(&adb->dcount.r) & APD) != 0;
255 }
256 out_8(&adb->error.r, 0);
257 out_8(&adb->intr.r, 0);
258 }
259 spin_unlock(&macio_lock);
260 if (complete && req) {
261 void (*done)(struct adb_request *) = req->done;
262 mb();
263 req->complete = 1;
264 /* Here, we assume that if the request has a done member, the
265 * struct request will survive to setting req->complete to 1
266 */
267 if (done)
268 (*done)(req);
269 }
270 if (ibuf_len)
271 adb_input(ibuf, ibuf_len, autopoll);
272
273 return IRQ_RETVAL(handled);
274}
275
276static void macio_adb_poll(void)
277{
278 unsigned long flags;
279
280 local_irq_save(flags);
281 if (in_8(&adb->intr.r) != 0)
282 macio_adb_interrupt(0, NULL);
283 local_irq_restore(flags);
284}