aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/input/serio/gscps2.c
blob: bd0f92d9f40f991c479d9237b851e381887f47e8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
/*
 * drivers/input/serio/gscps2.c
 *
 * Copyright (c) 2004-2006 Helge Deller <deller@gmx.de>
 * Copyright (c) 2002 Laurent Canet <canetl@esiee.fr>
 * Copyright (c) 2002 Thibaut Varene <varenet@parisc-linux.org>
 *
 * Pieces of code based on linux-2.4's hp_mouse.c & hp_keyb.c
 * 	Copyright (c) 1999 Alex deVries <alex@onefishtwo.ca>
 *	Copyright (c) 1999-2000 Philipp Rumpf <prumpf@tux.org>
 *	Copyright (c) 2000 Xavier Debacker <debackex@esiee.fr>
 *	Copyright (c) 2000-2001 Thomas Marteau <marteaut@esiee.fr>
 *
 * HP GSC PS/2 port driver, found in PA/RISC Workstations
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * TODO:
 * - Dino testing (did HP ever shipped a machine on which this port
 *                 was usable/enabled ?)
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/serio.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/pci_ids.h>

#include <asm/irq.h>
#include <asm/io.h>
#include <asm/parisc-device.h>

MODULE_AUTHOR("Laurent Canet <canetl@esiee.fr>, Thibaut Varene <varenet@parisc-linux.org>, Helge Deller <deller@gmx.de>");
MODULE_DESCRIPTION("HP GSC PS2 port driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(parisc, gscps2_device_tbl);

#define PFX "gscps2.c: "

/*
 * Driver constants
 */

/* various constants */
#define ENABLE			1
#define DISABLE			0

#define GSC_DINO_OFFSET		0x0800	/* offset for DINO controller versus LASI one */

/* PS/2 IO port offsets */
#define GSC_ID			0x00	/* device ID offset (see: GSC_ID_XXX) */
#define GSC_RESET		0x00	/* reset port offset */
#define GSC_RCVDATA		0x04	/* receive port offset */
#define GSC_XMTDATA		0x04	/* transmit port offset */
#define GSC_CONTROL		0x08	/* see: Control register bits */
#define GSC_STATUS		0x0C	/* see: Status register bits */

/* Control register bits */
#define GSC_CTRL_ENBL		0x01	/* enable interface */
#define GSC_CTRL_LPBXR		0x02	/* loopback operation */
#define GSC_CTRL_DIAG		0x20	/* directly control clock/data line */
#define GSC_CTRL_DATDIR		0x40	/* data line direct control */
#define GSC_CTRL_CLKDIR		0x80	/* clock line direct control */

/* Status register bits */
#define GSC_STAT_RBNE		0x01	/* Receive Buffer Not Empty */
#define GSC_STAT_TBNE		0x02	/* Transmit Buffer Not Empty */
#define GSC_STAT_TERR		0x04	/* Timeout Error */
#define GSC_STAT_PERR		0x08	/* Parity Error */
#define GSC_STAT_CMPINTR	0x10	/* Composite Interrupt = irq on any port */
#define GSC_STAT_DATSHD		0x40	/* Data Line Shadow */
#define GSC_STAT_CLKSHD		0x80	/* Clock Line Shadow */

/* IDs returned by GSC_ID port register */
#define GSC_ID_KEYBOARD		0	/* device ID values */
#define GSC_ID_MOUSE		1


static irqreturn_t gscps2_interrupt(int irq, void *dev);

#define BUFFER_SIZE 0x0f

/* GSC PS/2 port device struct */
struct gscps2port {
	struct list_head node;
	struct parisc_device *padev;
	struct serio *port;
	spinlock_t lock;
	char *addr;
	u8 act, append; /* position in buffer[] */
	struct {
		u8 data;
		u8 str;
	} buffer[BUFFER_SIZE+1];
	int id;
};

/*
 * Various HW level routines
 */

#define gscps2_readb_input(x)		readb((x)+GSC_RCVDATA)
#define gscps2_readb_control(x)		readb((x)+GSC_CONTROL)
#define gscps2_readb_status(x)		readb((x)+GSC_STATUS)
#define gscps2_writeb_control(x, y)	writeb((x), (y)+GSC_CONTROL)


/*
 * wait_TBE() - wait for Transmit Buffer Empty
 */

static int wait_TBE(char *addr)
{
	int timeout = 25000; /* device is expected to react within 250 msec */
	while (gscps2_readb_status(addr) & GSC_STAT_TBNE) {
		if (!--timeout)
			return 0;	/* This should not happen */
		udelay(10);
	}
	return 1;
}


/*
 * gscps2_flush() - flush the receive buffer
 */

static void gscps2_flush(struct gscps2port *ps2port)
{
	while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
		gscps2_readb_input(ps2port->addr);
	ps2port->act = ps2port->append = 0;
}

/*
 * gscps2_writeb_output() - write a byte to the port
 *
 * returns 1 on success, 0 on error
 */

static inline int gscps2_writeb_output(struct gscps2port *ps2port, u8 data)
{
	unsigned long flags;
	char *addr = ps2port->addr;

	if (!wait_TBE(addr)) {
		printk(KERN_DEBUG PFX "timeout - could not write byte %#x\n", data);
		return 0;
	}

	while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
		/* wait */;

	spin_lock_irqsave(&ps2port->lock, flags);
	writeb(data, addr+GSC_XMTDATA);
	spin_unlock_irqrestore(&ps2port->lock, flags);

	/* this is ugly, but due to timing of the port it seems to be necessary. */
	mdelay(6);

	/* make sure any received data is returned as fast as possible */
	/* this is important e.g. when we set the LEDs on the keyboard */
	gscps2_interrupt(0, NULL);

	return 1;
}


/*
 * gscps2_enable() - enables or disables the port
 */

static void gscps2_enable(struct gscps2port *ps2port, int enable)
{
	unsigned long flags;
	u8 data;

	/* now enable/disable the port */
	spin_lock_irqsave(&ps2port->lock, flags);
	gscps2_flush(ps2port);
	data = gscps2_readb_control(ps2port->addr);
	if (enable)
		data |= GSC_CTRL_ENBL;
	else
		data &= ~GSC_CTRL_ENBL;
	gscps2_writeb_control(data, ps2port->addr);
	spin_unlock_irqrestore(&ps2port->lock, flags);
	wait_TBE(ps2port->addr);
	gscps2_flush(ps2port);
}

/*
 * gscps2_reset() - resets the PS/2 port
 */

static void gscps2_reset(struct gscps2port *ps2port)
{
	char *addr = ps2port->addr;
	unsigned long flags;

	/* reset the interface */
	spin_lock_irqsave(&ps2port->lock, flags);
	gscps2_flush(ps2port);
	writeb(0xff, addr+GSC_RESET);
	gscps2_flush(ps2port);
	spin_unlock_irqrestore(&ps2port->lock, flags);
}

static LIST_HEAD(ps2port_list);

/**
 * gscps2_interrupt() - Interruption service routine
 *
 * This function reads received PS/2 bytes and processes them on
 * all interfaces.
 * The problematic part here is, that the keyboard and mouse PS/2 port
 * share the same interrupt and it's not possible to send data if any
 * one of them holds input data. To solve this problem we try to receive
 * the data as fast as possible and handle the reporting to the upper layer
 * later.
 */

static irqreturn_t gscps2_interrupt(int irq, void *dev)
{
	struct gscps2port *ps2port;

	list_for_each_entry(ps2port, &ps2port_list, node) {

	  unsigned long flags;
	  spin_lock_irqsave(&ps2port->lock, flags);

	  while ( (ps2port->buffer[ps2port->append].str =
		   gscps2_readb_status(ps2port->addr)) & GSC_STAT_RBNE ) {
		ps2port->buffer[ps2port->append].data =
				gscps2_readb_input(ps2port->addr);
		ps2port->append = ((ps2port->append+1) & BUFFER_SIZE);
	  }

	  spin_unlock_irqrestore(&ps2port->lock, flags);

	} /* list_for_each_entry */

	/* all data was read from the ports - now report the data to upper layer */

	list_for_each_entry(ps2port, &ps2port_list, node) {

	  while (ps2port->act != ps2port->append) {

	    unsigned int rxflags;
	    u8 data, status;

	    /* Did new data arrived while we read existing data ?
	       If yes, exit now and let the new irq handler start over again */
	    if (gscps2_readb_status(ps2port->addr) & GSC_STAT_CMPINTR)
		return IRQ_HANDLED;

	    status = ps2port->buffer[ps2port->act].str;
	    data   = ps2port->buffer[ps2port->act].data;

	    ps2port->act = ((ps2port->act+1) & BUFFER_SIZE);
	    rxflags =	((status & GSC_STAT_TERR) ? SERIO_TIMEOUT : 0 ) |
			((status & GSC_STAT_PERR) ? SERIO_PARITY  : 0 );

	    serio_interrupt(ps2port->port, data, rxflags);

	  } /* while() */

	} /* list_for_each_entry */

	return IRQ_HANDLED;
}


/*
 * gscps2_write() - send a byte out through the aux interface.
 */

static int gscps2_write(struct serio *port, unsigned char data)
{
	struct gscps2port *ps2port = port->port_data;

	if (!gscps2_writeb_output(ps2port, data)) {
		printk(KERN_DEBUG PFX "sending byte %#x failed.\n", data);
		return -1;
	}
	return 0;
}

/*
 * gscps2_open() is called when a port is opened by the higher layer.
 * It resets and enables the port.
 */

static int gscps2_open(struct serio *port)
{
	struct gscps2port *ps2port = port->port_data;

	gscps2_reset(ps2port);

	/* enable it */
	gscps2_enable(ps2port, ENABLE);

	gscps2_interrupt(0, NULL);

	return 0;
}

/*
 * gscps2_close() disables the port
 */

static void gscps2_close(struct serio *port)
{
	struct gscps2port *ps2port = port->port_data;
	gscps2_enable(ps2port, DISABLE);
}

/**
 * gscps2_probe() - Probes PS2 devices
 * @return: success/error report
 */

static int __init gscps2_probe(struct parisc_device *dev)
{
	struct gscps2port *ps2port;
	struct serio *serio;
	unsigned long hpa = dev->hpa.start;
	int ret;

	if (!dev->irq)
		return -ENODEV;

	/* Offset for DINO PS/2. Works with LASI even */
	if (dev->id.sversion == 0x96)
		hpa += GSC_DINO_OFFSET;

	ps2port = kzalloc(sizeof(struct gscps2port), GFP_KERNEL);
	serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
	if (!ps2port || !serio) {
		ret = -ENOMEM;
		goto fail_nomem;
	}

	dev_set_drvdata(&dev->dev, ps2port);

	ps2port->port = serio;
	ps2port->padev = dev;
	ps2port->addr = ioremap_nocache(hpa, GSC_STATUS + 4);
	spin_lock_init(&ps2port->lock);

	gscps2_reset(ps2port);
	ps2port->id = readb(ps2port->addr + GSC_ID) & 0x0f;

	snprintf(serio->name, sizeof(serio->name), "GSC PS/2 %s",
		 (ps2port->id == GSC_ID_KEYBOARD) ? "keyboard" : "mouse");
	strlcpy(serio->phys, dev_name(&dev->dev), sizeof(serio->phys));
	serio->id.type		= SERIO_8042;
	serio->write		= gscps2_write;
	serio->open		= gscps2_open;
	serio->close		= gscps2_close;
	serio->port_data	= ps2port;
	serio->dev.parent	= &dev->dev;

	ret = -EBUSY;
	if (request_irq(dev->irq, gscps2_interrupt, IRQF_SHARED, ps2port->port->name, ps2port))
		goto fail_miserably;

	if (ps2port->id != GSC_ID_KEYBOARD && ps2port->id != GSC_ID_MOUSE) {
		printk(KERN_WARNING PFX "Unsupported PS/2 port at 0x%08lx (id=%d) ignored\n",
				hpa, ps2port->id);
		ret = -ENODEV;
		goto fail;
	}

#if 0
	if (!request_mem_region(hpa, GSC_STATUS + 4, ps2port->port.name))
		goto fail;
#endif

	printk(KERN_INFO "serio: %s port at 0x%p irq %d @ %s\n",
		ps2port->port->name,
		ps2port->addr,
		ps2port->padev->irq,
		ps2port->port->phys);

	serio_register_port(ps2port->port);

	list_add_tail(&ps2port->node, &ps2port_list);

	return 0;

fail:
	free_irq(dev->irq, ps2port);

fail_miserably:
	iounmap(ps2port->addr);
	release_mem_region(dev->hpa.start, GSC_STATUS + 4);

fail_nomem:
	kfree(ps2port);
	kfree(serio);
	return ret;
}

/**
 * gscps2_remove() - Removes PS2 devices
 * @return: success/error report
 */

static int __devexit gscps2_remove(struct parisc_device *dev)
{
	struct gscps2port *ps2port = dev_get_drvdata(&dev->dev);

	serio_unregister_port(ps2port->port);
	free_irq(dev->irq, ps2port);
	gscps2_flush(ps2port);
	list_del(&ps2port->node);
	iounmap(ps2port->addr);
#if 0
	release_mem_region(dev->hpa, GSC_STATUS + 4);
#endif
	dev_set_drvdata(&dev->dev, NULL);
	kfree(ps2port);
	return 0;
}


static struct parisc_device_id gscps2_device_tbl[] = {
	{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00084 }, /* LASI PS/2 */
#ifdef DINO_TESTED
	{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00096 }, /* DINO PS/2 */
#endif
	{ 0, }	/* 0 terminated list */
};

static struct parisc_driver parisc_ps2_driver = {
	.name		= "gsc_ps2",
	.id_table	= gscps2_device_tbl,
	.probe		= gscps2_probe,
	.remove		= gscps2_remove,
};

static int __init gscps2_init(void)
{
	register_parisc_driver(&parisc_ps2_driver);
	return 0;
}

static void __exit gscps2_exit(void)
{
	unregister_parisc_driver(&parisc_ps2_driver);
}


module_init(gscps2_init);
module_exit(gscps2_exit);