[linux-block.git] / drivers / macintosh / adb-iop.c

// SPDX-License-Identifier: GPL-2.0
/*
 * I/O Processor (IOP) ADB Driver
 * Written and (C) 1999 by Joshua M. Thompson (funaho@jurai.org)
 * Based on via-cuda.c by Paul Mackerras.
 *
 * 1999-07-01 (jmt) - First implementation for new driver architecture.
 *
 * 1999-07-31 (jmt) - First working version.
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/init.h>

#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_iop.h>
#include <asm/adb_iop.h>
#include <asm/unaligned.h>

#include <linux/adb.h>

static struct adb_request *current_req;
static struct adb_request *last_req;
static unsigned int autopoll_devs;
static u8 autopoll_addr;

static enum adb_iop_state {
	idle,
	sending,
	awaiting_reply
} adb_iop_state;

static void adb_iop_start(void);
static int adb_iop_probe(void);
static int adb_iop_init(void);
static int adb_iop_send_request(struct adb_request *, int);
static int adb_iop_write(struct adb_request *);
static int adb_iop_autopoll(int);
static void adb_iop_poll(void);
static int adb_iop_reset_bus(void);

/* ADB command byte structure */
#define ADDR_MASK       0xF0
#define OP_MASK         0x0C
#define TALK            0x0C

struct adb_driver adb_iop_driver = {
	.name         = "ISM IOP",
	.probe        = adb_iop_probe,
	.init         = adb_iop_init,
	.send_request = adb_iop_send_request,
	.autopoll     = adb_iop_autopoll,
	.poll         = adb_iop_poll,
	.reset_bus    = adb_iop_reset_bus
};

static void adb_iop_done(void)
{
	struct adb_request *req = current_req;

	adb_iop_state = idle;

	req->complete = 1;
	current_req = req->next;
	if (req->done)
		(*req->done)(req);

	if (adb_iop_state == idle)
		adb_iop_start();
}

/*
 * Completion routine for ADB commands sent to the IOP.
 *
 * This will be called when a packet has been successfully sent.
 */

static void adb_iop_complete(struct iop_msg *msg)
{
	unsigned long flags;

	local_irq_save(flags);

	adb_iop_state = awaiting_reply;

	local_irq_restore(flags);
}

/*
 * Listen for ADB messages from the IOP.
 *
 * This will be called when unsolicited IOP messages are received.
 * These IOP messages can carry ADB autopoll responses and also occur
 * after explicit ADB commands.
 */

static void adb_iop_listen(struct iop_msg *msg)
{
	struct adb_iopmsg *amsg = (struct adb_iopmsg *)msg->message;
	u8 addr = (amsg->cmd & ADDR_MASK) >> 4;
	u8 op = amsg->cmd & OP_MASK;
	unsigned long flags;
	bool req_done = false;

	local_irq_save(flags);

	/* Responses to Talk commands may be unsolicited as they are
	 * produced when the IOP polls devices. They are mostly timeouts.
	 */
	if (op == TALK && ((1 << addr) & autopoll_devs))
		autopoll_addr = addr;

	switch (amsg->flags & (ADB_IOP_EXPLICIT |
			       ADB_IOP_AUTOPOLL |
			       ADB_IOP_TIMEOUT)) {
	case ADB_IOP_EXPLICIT:
	case ADB_IOP_EXPLICIT | ADB_IOP_TIMEOUT:
		if (adb_iop_state == awaiting_reply) {
			struct adb_request *req = current_req;

			if (req->reply_expected) {
				req->reply_len = amsg->count + 1;
				memcpy(req->reply, &amsg->cmd, req->reply_len);
			}

			req_done = true;
		}
		break;
	case ADB_IOP_AUTOPOLL:
		if (((1 << addr) & autopoll_devs) &&
		    amsg->cmd == ADB_READREG(addr, 0))
			adb_input(&amsg->cmd, amsg->count + 1, 1);
		break;
	}
	msg->reply[0] = autopoll_addr ? ADB_IOP_AUTOPOLL : 0;
	msg->reply[1] = 0;
	msg->reply[2] = autopoll_addr ? ADB_READREG(autopoll_addr, 0) : 0;
	iop_complete_message(msg);

	if (req_done)
		adb_iop_done();

	local_irq_restore(flags);
}

/*
 * Start sending an ADB packet, IOP style
 *
 * There isn't much to do other than hand the packet over to the IOP
 * after encapsulating it in an adb_iopmsg.
 */

static void adb_iop_start(void)
{
	struct adb_request *req;
	struct adb_iopmsg amsg;

	/* get the packet to send */
	req = current_req;
	if (!req)
		return;

	/* The IOP takes MacII-style packets, so strip the initial
	 * ADB_PACKET byte.
	 */
	amsg.flags = ADB_IOP_EXPLICIT;
	amsg.count = req->nbytes - 2;

	/* amsg.data immediately follows amsg.cmd, effectively making
	 * &amsg.cmd a pointer to the beginning of a full ADB packet.
	 */
	memcpy(&amsg.cmd, req->data + 1, req->nbytes - 1);

	req->sent = 1;
	adb_iop_state = sending;

	/* Now send it. The IOP manager will call adb_iop_complete
	 * when the message has been sent.
	 */
	iop_send_message(ADB_IOP, ADB_CHAN, req, sizeof(amsg), (__u8 *)&amsg,
			 adb_iop_complete);
}

static int adb_iop_probe(void)
{
	if (!iop_ism_present)
		return -ENODEV;
	return 0;
}

static int adb_iop_init(void)
{
	pr_info("adb: IOP ISM driver v0.4 for Unified ADB\n");
	iop_listen(ADB_IOP, ADB_CHAN, adb_iop_listen, "ADB");
	return 0;
}

static int adb_iop_send_request(struct adb_request *req, int sync)
{
	int err;

	err = adb_iop_write(req);
	if (err)
		return err;

	if (sync) {
		while (!req->complete)
			adb_iop_poll();
	}
	return 0;
}

static int adb_iop_write(struct adb_request *req)
{
	unsigned long flags;

	if ((req->nbytes < 2) || (req->data[0] != ADB_PACKET)) {
		req->complete = 1;
		return -EINVAL;
	}

	req->next = NULL;
	req->sent = 0;
	req->complete = 0;
	req->reply_len = 0;

	local_irq_save(flags);

	if (current_req) {
		last_req->next = req;
		last_req = req;
	} else {
		current_req = req;
		last_req = req;
	}

	if (adb_iop_state == idle)
		adb_iop_start();

	local_irq_restore(flags);

	return 0;
}

static void adb_iop_set_ap_complete(struct iop_msg *msg)
{
	struct adb_iopmsg *amsg = (struct adb_iopmsg *)msg->message;

	autopoll_devs = get_unaligned_be16(amsg->data);
	if (autopoll_devs & (1 << autopoll_addr))
		return;
	autopoll_addr = autopoll_devs ? (ffs(autopoll_devs) - 1) : 0;
}

static int adb_iop_autopoll(int devs)
{
	struct adb_iopmsg amsg;
	unsigned long flags;
	unsigned int mask = (unsigned int)devs & 0xFFFE;

	local_irq_save(flags);

	amsg.flags = ADB_IOP_SET_AUTOPOLL | (mask ? ADB_IOP_AUTOPOLL : 0);
	amsg.count = 2;
	amsg.cmd = 0;
	put_unaligned_be16(mask, amsg.data);

	iop_send_message(ADB_IOP, ADB_CHAN, NULL, sizeof(amsg), (__u8 *)&amsg,
			 adb_iop_set_ap_complete);

	local_irq_restore(flags);

	return 0;
}

static void adb_iop_poll(void)
{
	iop_ism_irq_poll(ADB_IOP);
}

static int adb_iop_reset_bus(void)
{
	struct adb_request req;

	/* Command = 0, Address = ignored */
	adb_request(&req, NULL, ADBREQ_NOSEND, 1, ADB_BUSRESET);
	adb_iop_send_request(&req, 1);

	/* Don't want any more requests during the Global Reset low time. */
	mdelay(3);

	return 0;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	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.
1da177e4 LT	10	*/
	11
	12	#include <linux/types.h>
	13	#include <linux/kernel.h>
	14	#include <linux/mm.h>
	15	#include <linux/delay.h>
	16	#include <linux/init.h>
1da177e4	17
47fd2060 FT	18	#include <asm/macintosh.h>
47fd2060 FT	19	#include <asm/macints.h>
1da177e4	20	#include <asm/mac_iop.h>
1da177e4	21	#include <asm/adb_iop.h>
c396dd2e	22	#include <asm/unaligned.h>
1da177e4	23
47fd2060	24	#include <linux/adb.h>
1da177e4	25
1da177e4 LT	26	static struct adb_request *current_req;
1da177e4 LT	27	static struct adb_request *last_req;
c66da95a	28	static unsigned int autopoll_devs;
10199e90	29	static u8 autopoll_addr;
1da177e4 LT	30
1da177e4 LT	31	static enum adb_iop_state {
47fd2060 FT	32	idle,
	33	sending,
	34	awaiting_reply
1da177e4 LT	35	} adb_iop_state;
	36
	37	static void adb_iop_start(void);
	38	static int adb_iop_probe(void);
	39	static int adb_iop_init(void);
	40	static int adb_iop_send_request(struct adb_request *, int);
	41	static int adb_iop_write(struct adb_request *);
	42	static int adb_iop_autopoll(int);
	43	static void adb_iop_poll(void);
	44	static int adb_iop_reset_bus(void);
	45
10199e90 FT	46	/* ADB command byte structure */
	47	#define ADDR_MASK 0xF0
	48	#define OP_MASK 0x0C
	49	#define TALK 0x0C
	50
1da177e4	51	struct adb_driver adb_iop_driver = {
3a52f6f9 FT	52	.name = "ISM IOP",
	53	.probe = adb_iop_probe,
	54	.init = adb_iop_init,
	55	.send_request = adb_iop_send_request,
	56	.autopoll = adb_iop_autopoll,
	57	.poll = adb_iop_poll,
	58	.reset_bus = adb_iop_reset_bus
1da177e4 LT	59	};
1da177e4 LT	60
32226e81	61	static void adb_iop_done(void)
1da177e4	62	{
32226e81 FT	63	struct adb_request *req = current_req;
	64
	65	adb_iop_state = idle;
	66
1da177e4 LT	67	req->complete = 1;
1da177e4 LT	68	current_req = req->next;
47fd2060 FT	69	if (req->done)
47fd2060 FT	70	(*req->done)(req);
32226e81 FT	71
	72	if (adb_iop_state == idle)
	73	adb_iop_start();
1da177e4 LT	74	}
	75
	76	/*
	77	* Completion routine for ADB commands sent to the IOP.
	78	*
	79	* This will be called when a packet has been successfully sent.
	80	*/
	81
7d12e780	82	static void adb_iop_complete(struct iop_msg *msg)
1da177e4	83	{
38b7a2ae	84	unsigned long flags;
1da177e4 LT	85
	86	local_irq_save(flags);
	87
2c9cfbad	88	adb_iop_state = awaiting_reply;
1da177e4 LT	89
	90	local_irq_restore(flags);
	91	}
	92
	93	/*
	94	* Listen for ADB messages from the IOP.
	95	*
2c9cfbad FT	96	* This will be called when unsolicited IOP messages are received.
	97	* These IOP messages can carry ADB autopoll responses and also occur
	98	* after explicit ADB commands.
1da177e4 LT	99	*/
1da177e4 LT	100
7d12e780	101	static void adb_iop_listen(struct iop_msg *msg)
1da177e4	102	{
47fd2060	103	struct adb_iopmsg amsg = (struct adb_iopmsg )msg->message;
10199e90 FT	104	u8 addr = (amsg->cmd & ADDR_MASK) >> 4;
10199e90 FT	105	u8 op = amsg->cmd & OP_MASK;
38b7a2ae	106	unsigned long flags;
32226e81	107	bool req_done = false;
1da177e4 LT	108
	109	local_irq_save(flags);
	110
10199e90 FT	111	/* Responses to Talk commands may be unsolicited as they are
10199e90 FT	112	* produced when the IOP polls devices. They are mostly timeouts.
ff785e17	113	*/
10199e90 FT	114	if (op == TALK && ((1 << addr) & autopoll_devs))
	115	autopoll_addr = addr;
	116
	117	switch (amsg->flags & (ADB_IOP_EXPLICIT \|
	118	ADB_IOP_AUTOPOLL \|
	119	ADB_IOP_TIMEOUT)) {
	120	case ADB_IOP_EXPLICIT:
	121	case ADB_IOP_EXPLICIT \| ADB_IOP_TIMEOUT:
32226e81 FT	122	if (adb_iop_state == awaiting_reply) {
	123	struct adb_request *req = current_req;
	124
2c9cfbad FT	125	if (req->reply_expected) {
	126	req->reply_len = amsg->count + 1;
	127	memcpy(req->reply, &amsg->cmd, req->reply_len);
	128	}
32226e81 FT	129
32226e81 FT	130	req_done = true;
1da177e4	131	}
10199e90 FT	132	break;
	133	case ADB_IOP_AUTOPOLL:
	134	if (((1 << addr) & autopoll_devs) &&
	135	amsg->cmd == ADB_READREG(addr, 0))
	136	adb_input(&amsg->cmd, amsg->count + 1, 1);
	137	break;
1da177e4	138	}
10199e90 FT	139	msg->reply[0] = autopoll_addr ? ADB_IOP_AUTOPOLL : 0;
	140	msg->reply[1] = 0;
	141	msg->reply[2] = autopoll_addr ? ADB_READREG(autopoll_addr, 0) : 0;
1da177e4	142	iop_complete_message(msg);
32226e81 FT	143
	144	if (req_done)
	145	adb_iop_done();
	146
1da177e4 LT	147	local_irq_restore(flags);
	148	}
	149
	150	/*
	151	* Start sending an ADB packet, IOP style
	152	*
	153	* There isn't much to do other than hand the packet over to the IOP
	154	* after encapsulating it in an adb_iopmsg.
	155	*/
	156
	157	static void adb_iop_start(void)
	158	{
1da177e4 LT	159	struct adb_request *req;
1da177e4 LT	160	struct adb_iopmsg amsg;
1da177e4 LT	161
	162	/* get the packet to send */
	163	req = current_req;
47fd2060 FT	164	if (!req)
47fd2060 FT	165	return;
1da177e4	166
ff785e17 FT	167	/* The IOP takes MacII-style packets, so strip the initial
	168	* ADB_PACKET byte.
	169	*/
1da177e4 LT	170	amsg.flags = ADB_IOP_EXPLICIT;
	171	amsg.count = req->nbytes - 2;
	172
ff785e17 FT	173	/* amsg.data immediately follows amsg.cmd, effectively making
	174	* &amsg.cmd a pointer to the beginning of a full ADB packet.
	175	*/
1da177e4 LT	176	memcpy(&amsg.cmd, req->data + 1, req->nbytes - 1);
	177
	178	req->sent = 1;
	179	adb_iop_state = sending;
1da177e4	180
ff785e17 FT	181	/* Now send it. The IOP manager will call adb_iop_complete
	182	* when the message has been sent.
	183	*/
47fd2060 FT	184	iop_send_message(ADB_IOP, ADB_CHAN, req, sizeof(amsg), (__u8 *)&amsg,
47fd2060 FT	185	adb_iop_complete);
1da177e4 LT	186	}
1da177e4 LT	187
56b732ed	188	static int adb_iop_probe(void)
1da177e4	189	{
47fd2060 FT	190	if (!iop_ism_present)
47fd2060 FT	191	return -ENODEV;
1da177e4 LT	192	return 0;
	193	}
	194
56b732ed	195	static int adb_iop_init(void)
1da177e4	196	{
351e5ad3	197	pr_info("adb: IOP ISM driver v0.4 for Unified ADB\n");
1da177e4 LT	198	iop_listen(ADB_IOP, ADB_CHAN, adb_iop_listen, "ADB");
	199	return 0;
	200	}
	201
56b732ed	202	static int adb_iop_send_request(struct adb_request *req, int sync)
1da177e4 LT	203	{
	204	int err;
	205
	206	err = adb_iop_write(req);
47fd2060 FT	207	if (err)
47fd2060 FT	208	return err;
1da177e4 LT	209
1da177e4 LT	210	if (sync) {
47fd2060 FT	211	while (!req->complete)
47fd2060 FT	212	adb_iop_poll();
1da177e4 LT	213	}
	214	return 0;
	215	}
	216
	217	static int adb_iop_write(struct adb_request *req)
	218	{
	219	unsigned long flags;
	220
	221	if ((req->nbytes < 2) \|\| (req->data[0] != ADB_PACKET)) {
	222	req->complete = 1;
	223	return -EINVAL;
	224	}
	225
a5d361fc	226	req->next = NULL;
1da177e4 LT	227	req->sent = 0;
	228	req->complete = 0;
	229	req->reply_len = 0;
	230
aac840ec FT	231	local_irq_save(flags);
aac840ec FT	232
56b732ed	233	if (current_req) {
1da177e4 LT	234	last_req->next = req;
	235	last_req = req;
	236	} else {
	237	current_req = req;
	238	last_req = req;
	239	}
	240
47fd2060 FT	241	if (adb_iop_state == idle)
47fd2060 FT	242	adb_iop_start();
aac840ec FT	243
	244	local_irq_restore(flags);
	245
1da177e4 LT	246	return 0;
	247	}
	248
c66da95a FT	249	static void adb_iop_set_ap_complete(struct iop_msg *msg)
	250	{
	251	struct adb_iopmsg amsg = (struct adb_iopmsg )msg->message;
	252
c396dd2e	253	autopoll_devs = get_unaligned_be16(amsg->data);
10199e90 FT	254	if (autopoll_devs & (1 << autopoll_addr))
	255	return;
	256	autopoll_addr = autopoll_devs ? (ffs(autopoll_devs) - 1) : 0;
c66da95a FT	257	}
c66da95a FT	258
56b732ed	259	static int adb_iop_autopoll(int devs)
1da177e4	260	{
c66da95a FT	261	struct adb_iopmsg amsg;
	262	unsigned long flags;
	263	unsigned int mask = (unsigned int)devs & 0xFFFE;
	264
	265	local_irq_save(flags);
	266
	267	amsg.flags = ADB_IOP_SET_AUTOPOLL \| (mask ? ADB_IOP_AUTOPOLL : 0);
	268	amsg.count = 2;
	269	amsg.cmd = 0;
c396dd2e	270	put_unaligned_be16(mask, amsg.data);
c66da95a FT	271
	272	iop_send_message(ADB_IOP, ADB_CHAN, NULL, sizeof(amsg), (__u8 *)&amsg,
	273	adb_iop_set_ap_complete);
	274
	275	local_irq_restore(flags);
	276
1da177e4 LT	277	return 0;
	278	}
	279
56b732ed	280	static void adb_iop_poll(void)
1da177e4	281	{
92178fca	282	iop_ism_irq_poll(ADB_IOP);
1da177e4 LT	283	}
1da177e4 LT	284
56b732ed	285	static int adb_iop_reset_bus(void)
1da177e4	286	{
303511ed FT	287	struct adb_request req;
	288
	289	/* Command = 0, Address = ignored */
	290	adb_request(&req, NULL, ADBREQ_NOSEND, 1, ADB_BUSRESET);
	291	adb_iop_send_request(&req, 1);
	292
	293	/* Don't want any more requests during the Global Reset low time. */
	294	mdelay(3);
1da177e4 LT	295
	296	return 0;
	297	}