2 * Driver for the ADB controller in the Mac I/O (Hydra) chip.
5 #include <linux/types.h>
6 #include <linux/errno.h>
7 #include <linux/kernel.h>
8 #include <linux/delay.h>
9 #include <linux/sched.h>
10 #include <linux/spinlock.h>
11 #include <linux/interrupt.h>
13 #include <linux/adb.h>
15 #include <asm/pgtable.h>
16 #include <asm/hydra.h>
18 #include <asm/system.h>
19 #include <linux/init.h>
34 struct preg active_hi
;
35 struct preg active_lo
;
39 /* Bits in intr and intr_enb registers */
40 #define DFB 1 /* data from bus */
41 #define TAG 2 /* transfer access grant */
43 /* Bits in dcount register */
44 #define HMB 0x0f /* how many bytes */
45 #define APD 0x10 /* auto-poll data */
47 /* Bits in error register */
48 #define NRE 1 /* no response error */
49 #define DLE 2 /* data lost error */
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 */
57 /* Bits in autopoll register */
58 #define APE 1 /* autopoll enable */
60 static volatile struct adb_regs __iomem
*adb
;
61 static struct adb_request
*current_req
, *last_req
;
62 static DEFINE_SPINLOCK(macio_lock
);
64 static int macio_probe(void);
65 static int macio_init(void);
66 static irqreturn_t
macio_adb_interrupt(int irq
, void *arg
, struct pt_regs
*regs
);
67 static int macio_send_request(struct adb_request
*req
, int sync
);
68 static int macio_adb_autopoll(int devs
);
69 static void macio_adb_poll(void);
70 static int macio_adb_reset_bus(void);
72 struct adb_driver macio_adb_driver
= {
85 return find_compatible_devices("adb", "chrp,adb0")? 0: -ENODEV
;
90 struct device_node
*adbs
;
92 adbs
= find_compatible_devices("adb", "chrp,adb0");
99 printk("macio_adb_init: node = %p, addrs =", adbs
->node
);
100 for (i
= 0; i
< adbs
->n_addrs
; ++i
)
101 printk(" %x(%x)", adbs
->addrs
[i
].address
, adbs
->addrs
[i
].size
);
103 for (i
= 0; i
< adbs
->n_intrs
; ++i
)
104 printk(" %x", adbs
->intrs
[i
].line
);
108 adb
= ioremap(adbs
->addrs
->address
, sizeof(struct adb_regs
));
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
);
117 if (request_irq(adbs
->intrs
[0].line
, macio_adb_interrupt
,
118 0, "ADB", (void *)0)) {
119 printk(KERN_ERR
"ADB: can't get irq %d\n",
120 adbs
->intrs
[0].line
);
123 out_8(&adb
->intr_enb
.r
, DFB
| TAG
);
125 printk("adb: mac-io driver 1.0 for unified ADB\n");
130 static int macio_adb_autopoll(int devs
)
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
);
142 static int macio_adb_reset_bus(void)
145 int timeout
= 1000000;
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 seldomly used during boot
150 * on rare machines, so...
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
);
160 spin_unlock_irqrestore(&macio_lock
, flags
);
164 /* Send an ADB command */
165 static int macio_send_request(struct adb_request
*req
, int sync
)
170 if (req
->data
[0] != ADB_PACKET
)
173 for (i
= 0; i
< req
->nbytes
- 1; ++i
)
174 req
->data
[i
] = req
->data
[i
+1];
182 spin_lock_irqsave(&macio_lock
, flags
);
183 if (current_req
!= 0) {
184 last_req
->next
= req
;
187 current_req
= last_req
= req
;
188 out_8(&adb
->ctrl
.r
, in_8(&adb
->ctrl
.r
) | TAR
);
190 spin_unlock_irqrestore(&macio_lock
, flags
);
193 while (!req
->complete
)
200 static irqreturn_t
macio_adb_interrupt(int irq
, void *arg
,
201 struct pt_regs
*regs
)
204 struct adb_request
*req
= NULL
;
205 unsigned char ibuf
[16];
211 spin_lock(&macio_lock
);
212 if (in_8(&adb
->intr
.r
) & TAG
) {
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
);
220 if (req
->reply_expected
) {
221 out_8(&adb
->ctrl
.r
, DTB
+ CRE
);
223 out_8(&adb
->ctrl
.r
, DTB
);
224 current_req
= req
->next
;
227 out_8(&adb
->ctrl
.r
, in_8(&adb
->ctrl
.r
) | TAR
);
230 out_8(&adb
->intr
.r
, 0);
233 if (in_8(&adb
->intr
.r
) & DFB
) {
235 err
= in_8(&adb
->error
.r
);
236 if (current_req
&& current_req
->sent
) {
237 /* this is the response to a command */
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
);
244 current_req
= req
->next
;
247 out_8(&adb
->ctrl
.r
, in_8(&adb
->ctrl
.r
) | TAR
);
248 } else if (err
== 0) {
250 n
= in_8(&adb
->dcount
.r
) & HMB
;
251 for (i
= 0; i
< n
; ++i
)
252 ibuf
[i
] = in_8(&adb
->data
[i
].r
);
254 autopoll
= (in_8(&adb
->dcount
.r
) & APD
) != 0;
256 out_8(&adb
->error
.r
, 0);
257 out_8(&adb
->intr
.r
, 0);
259 spin_unlock(&macio_lock
);
260 if (complete
&& req
) {
261 void (*done
)(struct adb_request
*) = req
->done
;
264 /* Here, we assume that if the request has a done member, the
265 * struct request will survive to setting req->complete to 1
271 adb_input(ibuf
, ibuf_len
, regs
, autopoll
);
273 return IRQ_RETVAL(handled
);
276 static void macio_adb_poll(void)
280 local_irq_save(flags
);
281 if (in_8(&adb
->intr
.r
) != 0)
282 macio_adb_interrupt(0, NULL
, NULL
);
283 local_irq_restore(flags
);