xref: /openbmc/linux/drivers/pcmcia/db1xxx_ss.c (revision e0d07278)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * PCMCIA socket code for the Alchemy Db1xxx/Pb1xxx boards.
4  *
5  * Copyright (c) 2009 Manuel Lauss <manuel.lauss@gmail.com>
6  *
7  */
8 
9 /* This is a fairly generic PCMCIA socket driver suitable for the
10  * following Alchemy Development boards:
11  *  Db1000, Db/Pb1500, Db/Pb1100, Db/Pb1550, Db/Pb1200, Db1300
12  *
13  * The Db1000 is used as a reference:  Per-socket card-, carddetect- and
14  *  statuschange IRQs connected to SoC GPIOs, control and status register
15  *  bits arranged in per-socket groups in an external PLD.  All boards
16  *  listed here use this layout, including bit positions and meanings.
17  *  Of course there are exceptions in later boards:
18  *
19  *	- Pb1100/Pb1500:  single socket only; voltage key bits VS are
20  *			  at STATUS[5:4] (instead of STATUS[1:0]).
21  *	- Au1200-based:	  additional card-eject irqs, irqs not gpios!
22  *	- Db1300:	  Db1200-like, no pwr ctrl, single socket (#1).
23  */
24 
25 #include <linux/delay.h>
26 #include <linux/gpio.h>
27 #include <linux/interrupt.h>
28 #include <linux/pm.h>
29 #include <linux/module.h>
30 #include <linux/platform_device.h>
31 #include <linux/resource.h>
32 #include <linux/slab.h>
33 #include <linux/spinlock.h>
34 
35 #include <pcmcia/ss.h>
36 
37 #include <asm/mach-au1x00/au1000.h>
38 #include <asm/mach-db1x00/bcsr.h>
39 
40 #define MEM_MAP_SIZE	0x400000
41 #define IO_MAP_SIZE	0x1000
42 
43 struct db1x_pcmcia_sock {
44 	struct pcmcia_socket	socket;
45 	int		nr;		/* socket number */
46 	void		*virt_io;
47 
48 	phys_addr_t	phys_io;
49 	phys_addr_t	phys_attr;
50 	phys_addr_t	phys_mem;
51 
52 	/* previous flags for set_socket() */
53 	unsigned int old_flags;
54 
55 	/* interrupt sources: linux irq numbers! */
56 	int	insert_irq;	/* default carddetect irq */
57 	int	stschg_irq;	/* card-status-change irq */
58 	int	card_irq;	/* card irq */
59 	int	eject_irq;	/* db1200/pb1200 have these */
60 	int	insert_gpio;	/* db1000 carddetect gpio */
61 
62 #define BOARD_TYPE_DEFAULT	0	/* most boards */
63 #define BOARD_TYPE_DB1200	1	/* IRQs aren't gpios */
64 #define BOARD_TYPE_PB1100	2	/* VS bits slightly different */
65 #define BOARD_TYPE_DB1300	3	/* no power control */
66 	int	board_type;
67 };
68 
69 #define to_db1x_socket(x) container_of(x, struct db1x_pcmcia_sock, socket)
70 
71 static int db1300_card_inserted(struct db1x_pcmcia_sock *sock)
72 {
73 	return bcsr_read(BCSR_SIGSTAT) & (1 << 8);
74 }
75 
76 /* DB/PB1200: check CPLD SIGSTATUS register bit 10/12 */
77 static int db1200_card_inserted(struct db1x_pcmcia_sock *sock)
78 {
79 	unsigned short sigstat;
80 
81 	sigstat = bcsr_read(BCSR_SIGSTAT);
82 	return sigstat & 1 << (8 + 2 * sock->nr);
83 }
84 
85 /* carddetect gpio: low-active */
86 static int db1000_card_inserted(struct db1x_pcmcia_sock *sock)
87 {
88 	return !gpio_get_value(sock->insert_gpio);
89 }
90 
91 static int db1x_card_inserted(struct db1x_pcmcia_sock *sock)
92 {
93 	switch (sock->board_type) {
94 	case BOARD_TYPE_DB1200:
95 		return db1200_card_inserted(sock);
96 	case BOARD_TYPE_DB1300:
97 		return db1300_card_inserted(sock);
98 	default:
99 		return db1000_card_inserted(sock);
100 	}
101 }
102 
103 /* STSCHG tends to bounce heavily when cards are inserted/ejected.
104  * To avoid this, the interrupt is normally disabled and only enabled
105  * after reset to a card has been de-asserted.
106  */
107 static inline void set_stschg(struct db1x_pcmcia_sock *sock, int en)
108 {
109 	if (sock->stschg_irq != -1) {
110 		if (en)
111 			enable_irq(sock->stschg_irq);
112 		else
113 			disable_irq(sock->stschg_irq);
114 	}
115 }
116 
117 static irqreturn_t db1000_pcmcia_cdirq(int irq, void *data)
118 {
119 	struct db1x_pcmcia_sock *sock = data;
120 
121 	pcmcia_parse_events(&sock->socket, SS_DETECT);
122 
123 	return IRQ_HANDLED;
124 }
125 
126 static irqreturn_t db1000_pcmcia_stschgirq(int irq, void *data)
127 {
128 	struct db1x_pcmcia_sock *sock = data;
129 
130 	pcmcia_parse_events(&sock->socket, SS_STSCHG);
131 
132 	return IRQ_HANDLED;
133 }
134 
135 /* Db/Pb1200 have separate per-socket insertion and ejection
136  * interrupts which stay asserted as long as the card is
137  * inserted/missing.  The one which caused us to be called
138  * needs to be disabled and the other one enabled.
139  */
140 static irqreturn_t db1200_pcmcia_cdirq(int irq, void *data)
141 {
142 	disable_irq_nosync(irq);
143 	return IRQ_WAKE_THREAD;
144 }
145 
146 static irqreturn_t db1200_pcmcia_cdirq_fn(int irq, void *data)
147 {
148 	struct db1x_pcmcia_sock *sock = data;
149 
150 	/* Wait a bit for the signals to stop bouncing. */
151 	msleep(100);
152 	if (irq == sock->insert_irq)
153 		enable_irq(sock->eject_irq);
154 	else
155 		enable_irq(sock->insert_irq);
156 
157 	pcmcia_parse_events(&sock->socket, SS_DETECT);
158 
159 	return IRQ_HANDLED;
160 }
161 
162 static int db1x_pcmcia_setup_irqs(struct db1x_pcmcia_sock *sock)
163 {
164 	int ret;
165 
166 	if (sock->stschg_irq != -1) {
167 		ret = request_irq(sock->stschg_irq, db1000_pcmcia_stschgirq,
168 				  0, "pcmcia_stschg", sock);
169 		if (ret)
170 			return ret;
171 	}
172 
173 	/* Db/Pb1200 have separate per-socket insertion and ejection
174 	 * interrupts, which should show edge behaviour but don't.
175 	 * So interrupts are disabled until both insertion and
176 	 * ejection handler have been registered and the currently
177 	 * active one disabled.
178 	 */
179 	if ((sock->board_type == BOARD_TYPE_DB1200) ||
180 	    (sock->board_type == BOARD_TYPE_DB1300)) {
181 		ret = request_threaded_irq(sock->insert_irq, db1200_pcmcia_cdirq,
182 			db1200_pcmcia_cdirq_fn, 0, "pcmcia_insert", sock);
183 		if (ret)
184 			goto out1;
185 
186 		ret = request_threaded_irq(sock->eject_irq, db1200_pcmcia_cdirq,
187 			db1200_pcmcia_cdirq_fn, 0, "pcmcia_eject", sock);
188 		if (ret) {
189 			free_irq(sock->insert_irq, sock);
190 			goto out1;
191 		}
192 
193 		/* enable the currently silent one */
194 		if (db1x_card_inserted(sock))
195 			enable_irq(sock->eject_irq);
196 		else
197 			enable_irq(sock->insert_irq);
198 	} else {
199 		/* all other (older) Db1x00 boards use a GPIO to show
200 		 * card detection status:  use both-edge triggers.
201 		 */
202 		irq_set_irq_type(sock->insert_irq, IRQ_TYPE_EDGE_BOTH);
203 		ret = request_irq(sock->insert_irq, db1000_pcmcia_cdirq,
204 				  0, "pcmcia_carddetect", sock);
205 
206 		if (ret)
207 			goto out1;
208 	}
209 
210 	return 0;	/* all done */
211 
212 out1:
213 	if (sock->stschg_irq != -1)
214 		free_irq(sock->stschg_irq, sock);
215 
216 	return ret;
217 }
218 
219 static void db1x_pcmcia_free_irqs(struct db1x_pcmcia_sock *sock)
220 {
221 	if (sock->stschg_irq != -1)
222 		free_irq(sock->stschg_irq, sock);
223 
224 	free_irq(sock->insert_irq, sock);
225 	if (sock->eject_irq != -1)
226 		free_irq(sock->eject_irq, sock);
227 }
228 
229 /*
230  * configure a PCMCIA socket on the Db1x00 series of boards (and
231  * compatibles).
232  *
233  * 2 external registers are involved:
234  *   pcmcia_status (offset 0x04): bits [0:1/2:3]: read card voltage id
235  *   pcmcia_control(offset 0x10):
236  *	bits[0:1] set vcc for card
237  *	bits[2:3] set vpp for card
238  *	bit 4:	enable data buffers
239  *	bit 7:	reset# for card
240  *	add 8 for second socket.
241  */
242 static int db1x_pcmcia_configure(struct pcmcia_socket *skt,
243 				 struct socket_state_t *state)
244 {
245 	struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
246 	unsigned short cr_clr, cr_set;
247 	unsigned int changed;
248 	int v, p, ret;
249 
250 	/* card voltage setup */
251 	cr_clr = (0xf << (sock->nr * 8)); /* clear voltage settings */
252 	cr_set = 0;
253 	v = p = ret = 0;
254 
255 	switch (state->Vcc) {
256 	case 50:
257 		++v;
258 		fallthrough;
259 	case 33:
260 		++v;
261 		fallthrough;
262 	case 0:
263 		break;
264 	default:
265 		printk(KERN_INFO "pcmcia%d unsupported Vcc %d\n",
266 			sock->nr, state->Vcc);
267 	}
268 
269 	switch (state->Vpp) {
270 	case 12:
271 		++p;
272 		fallthrough;
273 	case 33:
274 	case 50:
275 		++p;
276 		fallthrough;
277 	case 0:
278 		break;
279 	default:
280 		printk(KERN_INFO "pcmcia%d unsupported Vpp %d\n",
281 			sock->nr, state->Vpp);
282 	}
283 
284 	/* sanity check: Vpp must be 0, 12, or Vcc */
285 	if (((state->Vcc == 33) && (state->Vpp == 50)) ||
286 	    ((state->Vcc == 50) && (state->Vpp == 33))) {
287 		printk(KERN_INFO "pcmcia%d bad Vcc/Vpp combo (%d %d)\n",
288 			sock->nr, state->Vcc, state->Vpp);
289 		v = p = 0;
290 		ret = -EINVAL;
291 	}
292 
293 	/* create new voltage code */
294 	if (sock->board_type != BOARD_TYPE_DB1300)
295 		cr_set |= ((v << 2) | p) << (sock->nr * 8);
296 
297 	changed = state->flags ^ sock->old_flags;
298 
299 	if (changed & SS_RESET) {
300 		if (state->flags & SS_RESET) {
301 			set_stschg(sock, 0);
302 			/* assert reset, disable io buffers */
303 			cr_clr |= (1 << (7 + (sock->nr * 8)));
304 			cr_clr |= (1 << (4 + (sock->nr * 8)));
305 		} else {
306 			/* de-assert reset, enable io buffers */
307 			cr_set |= 1 << (7 + (sock->nr * 8));
308 			cr_set |= 1 << (4 + (sock->nr * 8));
309 		}
310 	}
311 
312 	/* update PCMCIA configuration */
313 	bcsr_mod(BCSR_PCMCIA, cr_clr, cr_set);
314 
315 	sock->old_flags = state->flags;
316 
317 	/* reset was taken away: give card time to initialize properly */
318 	if ((changed & SS_RESET) && !(state->flags & SS_RESET)) {
319 		msleep(500);
320 		set_stschg(sock, 1);
321 	}
322 
323 	return ret;
324 }
325 
326 /* VCC bits at [3:2]/[11:10] */
327 #define GET_VCC(cr, socknr)		\
328 	((((cr) >> 2) >> ((socknr) * 8)) & 3)
329 
330 /* VS bits at [0:1]/[3:2] */
331 #define GET_VS(sr, socknr)		\
332 	(((sr) >> (2 * (socknr))) & 3)
333 
334 /* reset bits at [7]/[15] */
335 #define GET_RESET(cr, socknr)		\
336 	((cr) & (1 << (7 + (8 * (socknr)))))
337 
338 static int db1x_pcmcia_get_status(struct pcmcia_socket *skt,
339 				  unsigned int *value)
340 {
341 	struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
342 	unsigned short cr, sr;
343 	unsigned int status;
344 
345 	status = db1x_card_inserted(sock) ? SS_DETECT : 0;
346 
347 	cr = bcsr_read(BCSR_PCMCIA);
348 	sr = bcsr_read(BCSR_STATUS);
349 
350 	/* PB1100/PB1500: voltage key bits are at [5:4] */
351 	if (sock->board_type == BOARD_TYPE_PB1100)
352 		sr >>= 4;
353 
354 	/* determine card type */
355 	switch (GET_VS(sr, sock->nr)) {
356 	case 0:
357 	case 2:
358 		status |= SS_3VCARD;	/* 3V card */
359 	case 3:
360 		break;			/* 5V card: set nothing */
361 	default:
362 		status |= SS_XVCARD;	/* treated as unsupported in core */
363 	}
364 
365 	/* if Vcc is not zero, we have applied power to a card */
366 	status |= GET_VCC(cr, sock->nr) ? SS_POWERON : 0;
367 
368 	/* DB1300: power always on, but don't tell when no card present */
369 	if ((sock->board_type == BOARD_TYPE_DB1300) && (status & SS_DETECT))
370 		status = SS_POWERON | SS_3VCARD | SS_DETECT;
371 
372 	/* reset de-asserted? then we're ready */
373 	status |= (GET_RESET(cr, sock->nr)) ? SS_READY : SS_RESET;
374 
375 	*value = status;
376 
377 	return 0;
378 }
379 
380 static int db1x_pcmcia_sock_init(struct pcmcia_socket *skt)
381 {
382 	return 0;
383 }
384 
385 static int db1x_pcmcia_sock_suspend(struct pcmcia_socket *skt)
386 {
387 	return 0;
388 }
389 
390 static int au1x00_pcmcia_set_io_map(struct pcmcia_socket *skt,
391 				    struct pccard_io_map *map)
392 {
393 	struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
394 
395 	map->start = (u32)sock->virt_io;
396 	map->stop = map->start + IO_MAP_SIZE;
397 
398 	return 0;
399 }
400 
401 static int au1x00_pcmcia_set_mem_map(struct pcmcia_socket *skt,
402 				     struct pccard_mem_map *map)
403 {
404 	struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
405 
406 	if (map->flags & MAP_ATTRIB)
407 		map->static_start = sock->phys_attr + map->card_start;
408 	else
409 		map->static_start = sock->phys_mem + map->card_start;
410 
411 	return 0;
412 }
413 
414 static struct pccard_operations db1x_pcmcia_operations = {
415 	.init			= db1x_pcmcia_sock_init,
416 	.suspend		= db1x_pcmcia_sock_suspend,
417 	.get_status		= db1x_pcmcia_get_status,
418 	.set_socket		= db1x_pcmcia_configure,
419 	.set_io_map		= au1x00_pcmcia_set_io_map,
420 	.set_mem_map		= au1x00_pcmcia_set_mem_map,
421 };
422 
423 static int db1x_pcmcia_socket_probe(struct platform_device *pdev)
424 {
425 	struct db1x_pcmcia_sock *sock;
426 	struct resource *r;
427 	int ret, bid;
428 
429 	sock = kzalloc(sizeof(struct db1x_pcmcia_sock), GFP_KERNEL);
430 	if (!sock)
431 		return -ENOMEM;
432 
433 	sock->nr = pdev->id;
434 
435 	bid = BCSR_WHOAMI_BOARD(bcsr_read(BCSR_WHOAMI));
436 	switch (bid) {
437 	case BCSR_WHOAMI_PB1500:
438 	case BCSR_WHOAMI_PB1500R2:
439 	case BCSR_WHOAMI_PB1100:
440 		sock->board_type = BOARD_TYPE_PB1100;
441 		break;
442 	case BCSR_WHOAMI_DB1000 ... BCSR_WHOAMI_PB1550_SDR:
443 		sock->board_type = BOARD_TYPE_DEFAULT;
444 		break;
445 	case BCSR_WHOAMI_PB1200 ... BCSR_WHOAMI_DB1200:
446 		sock->board_type = BOARD_TYPE_DB1200;
447 		break;
448 	case BCSR_WHOAMI_DB1300:
449 		sock->board_type = BOARD_TYPE_DB1300;
450 		break;
451 	default:
452 		printk(KERN_INFO "db1xxx-ss: unknown board %d!\n", bid);
453 		ret = -ENODEV;
454 		goto out0;
455 	};
456 
457 	/*
458 	 * gather resources necessary and optional nice-to-haves to
459 	 * operate a socket:
460 	 * This includes IRQs for Carddetection/ejection, the card
461 	 *  itself and optional status change detection.
462 	 * Also, the memory areas covered by a socket.  For these
463 	 *  we require the real 36bit addresses (see the au1000.h
464 	 *  header for more information).
465 	 */
466 
467 	/* card: irq assigned to the card itself. */
468 	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "card");
469 	sock->card_irq = r ? r->start : 0;
470 
471 	/* insert: irq which triggers on card insertion/ejection
472 	 * BIG FAT NOTE: on DB1000/1100/1500/1550 we pass a GPIO here!
473 	 */
474 	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "insert");
475 	sock->insert_irq = r ? r->start : -1;
476 	if (sock->board_type == BOARD_TYPE_DEFAULT) {
477 		sock->insert_gpio = r ? r->start : -1;
478 		sock->insert_irq = r ? gpio_to_irq(r->start) : -1;
479 	}
480 
481 	/* stschg: irq which trigger on card status change (optional) */
482 	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "stschg");
483 	sock->stschg_irq = r ? r->start : -1;
484 
485 	/* eject: irq which triggers on ejection (DB1200/PB1200 only) */
486 	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "eject");
487 	sock->eject_irq = r ? r->start : -1;
488 
489 	ret = -ENODEV;
490 
491 	/* 36bit PCMCIA Attribute area address */
492 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-attr");
493 	if (!r) {
494 		printk(KERN_ERR "pcmcia%d has no 'pseudo-attr' resource!\n",
495 			sock->nr);
496 		goto out0;
497 	}
498 	sock->phys_attr = r->start;
499 
500 	/* 36bit PCMCIA Memory area address */
501 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-mem");
502 	if (!r) {
503 		printk(KERN_ERR "pcmcia%d has no 'pseudo-mem' resource!\n",
504 			sock->nr);
505 		goto out0;
506 	}
507 	sock->phys_mem = r->start;
508 
509 	/* 36bit PCMCIA IO area address */
510 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-io");
511 	if (!r) {
512 		printk(KERN_ERR "pcmcia%d has no 'pseudo-io' resource!\n",
513 			sock->nr);
514 		goto out0;
515 	}
516 	sock->phys_io = r->start;
517 
518 	/*
519 	 * PCMCIA client drivers use the inb/outb macros to access
520 	 * the IO registers.  Since mips_io_port_base is added
521 	 * to the access address of the mips implementation of
522 	 * inb/outb, we need to subtract it here because we want
523 	 * to access the I/O or MEM address directly, without
524 	 * going through this "mips_io_port_base" mechanism.
525 	 */
526 	sock->virt_io = (void *)(ioremap(sock->phys_io, IO_MAP_SIZE) -
527 				 mips_io_port_base);
528 
529 	if (!sock->virt_io) {
530 		printk(KERN_ERR "pcmcia%d: cannot remap IO area\n",
531 			sock->nr);
532 		ret = -ENOMEM;
533 		goto out0;
534 	}
535 
536 	sock->socket.ops	= &db1x_pcmcia_operations;
537 	sock->socket.owner	= THIS_MODULE;
538 	sock->socket.pci_irq	= sock->card_irq;
539 	sock->socket.features	= SS_CAP_STATIC_MAP | SS_CAP_PCCARD;
540 	sock->socket.map_size	= MEM_MAP_SIZE;
541 	sock->socket.io_offset	= (unsigned long)sock->virt_io;
542 	sock->socket.dev.parent	= &pdev->dev;
543 	sock->socket.resource_ops = &pccard_static_ops;
544 
545 	platform_set_drvdata(pdev, sock);
546 
547 	ret = db1x_pcmcia_setup_irqs(sock);
548 	if (ret) {
549 		printk(KERN_ERR "pcmcia%d cannot setup interrupts\n",
550 			sock->nr);
551 		goto out1;
552 	}
553 
554 	set_stschg(sock, 0);
555 
556 	ret = pcmcia_register_socket(&sock->socket);
557 	if (ret) {
558 		printk(KERN_ERR "pcmcia%d failed to register\n", sock->nr);
559 		goto out2;
560 	}
561 
562 	printk(KERN_INFO "Alchemy Db/Pb1xxx pcmcia%d @ io/attr/mem %09llx"
563 		"(%p) %09llx %09llx  card/insert/stschg/eject irqs @ %d "
564 		"%d %d %d\n", sock->nr, sock->phys_io, sock->virt_io,
565 		sock->phys_attr, sock->phys_mem, sock->card_irq,
566 		sock->insert_irq, sock->stschg_irq, sock->eject_irq);
567 
568 	return 0;
569 
570 out2:
571 	db1x_pcmcia_free_irqs(sock);
572 out1:
573 	iounmap((void *)(sock->virt_io + (u32)mips_io_port_base));
574 out0:
575 	kfree(sock);
576 	return ret;
577 }
578 
579 static int db1x_pcmcia_socket_remove(struct platform_device *pdev)
580 {
581 	struct db1x_pcmcia_sock *sock = platform_get_drvdata(pdev);
582 
583 	db1x_pcmcia_free_irqs(sock);
584 	pcmcia_unregister_socket(&sock->socket);
585 	iounmap((void *)(sock->virt_io + (u32)mips_io_port_base));
586 	kfree(sock);
587 
588 	return 0;
589 }
590 
591 static struct platform_driver db1x_pcmcia_socket_driver = {
592 	.driver	= {
593 		.name	= "db1xxx_pcmcia",
594 	},
595 	.probe		= db1x_pcmcia_socket_probe,
596 	.remove		= db1x_pcmcia_socket_remove,
597 };
598 
599 module_platform_driver(db1x_pcmcia_socket_driver);
600 
601 MODULE_LICENSE("GPL");
602 MODULE_DESCRIPTION("PCMCIA Socket Services for Alchemy Db/Pb1x00 boards");
603 MODULE_AUTHOR("Manuel Lauss");
604