1 // SPDX-License-Identifier: GPL-2.0
3  * Device driver for the via ADB on (many) Mac II-class machines
13  * 1999-08-02 (jmt) - Initial rewrite for Unified ADB.
14  * 2000-03-29 Tony Mantler <tonym@mac.linux-m68k.org>
15  *            - Big overhaul, should actually work now.
16  * 2006-12-31 Finn Thain - Another overhaul.
24  *   ftp://ftp.apple.com/developer/Tool_Chest/Devices_-_Hardware/Apple_Desktop_Bus/
39 /* VIA registers - spaced 0x200 bytes apart */
41 #define B		0		/* B-side data */
42 #define A		RS		/* A-side data */
43 #define DIRB		(2*RS)		/* B-side direction (1=output) */
44 #define DIRA		(3*RS)		/* A-side direction (1=output) */
56 #define ANH		(15*RS)		/* A-side data, no handshake */
72 /* ADB transaction states according to GMHW */
116 static unsigned char *reply_ptr;     /* next byte in reply_buf or req->reply */
117 static bool reading_reply;       /* store reply in reply_buf else req->reply */
118 static int data_index;      /* index of the next byte to send from req->data */
119 static int reply_len; /* number of bytes received in reply_buf or req->reply */
131 	if (macintosh_config->adb_type != MAC_ADB_II)  in macii_probe()
132 		return -ENODEV;  in macii_probe()
168 	/* We want CTLR_IRQ as input and ST_EVEN | ST_ODD as output lines. */  in macii_init_via()
208 		higher_devs = autopoll_devs & -(1 << (poll_addr + 1));  in macii_queue_poll()
209 		poll_addr = ffs(higher_devs ? higher_devs : autopoll_devs) - 1;  in macii_queue_poll()
246 		while (!req->complete)  in macii_send_request()
257 	if (req->nbytes < 2 || req->data[0] != ADB_PACKET || req->nbytes > 15) {  in macii_write()
258 		req->complete = 1;  in macii_write()
259 		return -EINVAL;  in macii_write()
262 	req->next = NULL;  in macii_write()
263 	req->sent = 0;  in macii_write()
264 	req->complete = 0;  in macii_write()
265 	req->reply_len = 0;  in macii_write()
270 		last_req->next = req;  in macii_write()
284 /* Start auto-polling */
335 	 * And req->nbytes is the number of bytes of real data plus one.  in macii_start()
341 	via[SR] = req->data[1];  in macii_start()
353  * The notorious ADB interrupt handler - does all of the protocol handling.
359  * sees a transition on the PB4 and PB5 lines it will crank over the VIA shift
364  *     CMD -> IDLE
366  *     CMD -> EVEN -> ODD -> EVEN -> ... -> IDLE
368  *     IDLE -> EVEN -> ODD -> EVEN -> ... -> IDLE
423 			/* /CTLR_IRQ de-asserted after the command byte means  in macii_interrupt()
428 			last_cmd = req->data[1];  in macii_interrupt()
451 		} else if (data_index >= req->nbytes) {  in macii_interrupt()
452 			req->sent = 1;  in macii_interrupt()
454 			if (req->reply_expected) {  in macii_interrupt()
458 				reply_ptr = req->reply;  in macii_interrupt()
459 				*reply_ptr = req->data[1];  in macii_interrupt()
464 			} else if ((req->data[1] & OP_MASK) == TALK) {  in macii_interrupt()
469 				*reply_ptr = req->data[1];  in macii_interrupt()
475 				req->complete = 1;  in macii_interrupt()
476 				current_req = req->next;  in macii_interrupt()
477 				if (req->done)  in macii_interrupt()
478 					(*req->done)(req);  in macii_interrupt()
482 				req->complete = 1;  in macii_interrupt()
483 				current_req = req->next;  in macii_interrupt()
484 				if (req->done)  in macii_interrupt()
485 					(*req->done)(req);  in macii_interrupt()
489 			via[SR] = req->data[data_index++];  in macii_interrupt()
520 					req->reply_len = reply_len;  in macii_interrupt()
522 					req->complete = 1;  in macii_interrupt()
523 					current_req = req->next;  in macii_interrupt()
524 					if (req->done)  in macii_interrupt()
525 						(*req->done)(req);  in macii_interrupt()