1 /*
2 * drivers/input/serio/gscps2.c
3 *
4 * Copyright (c) 2004-2006 Helge Deller <deller@gmx.de>
5 * Copyright (c) 2002 Laurent Canet <canetl@esiee.fr>
6 * Copyright (c) 2002 Thibaut Varene <varenet@parisc-linux.org>
7 *
8 * Pieces of code based on linux-2.4's hp_mouse.c & hp_keyb.c
9 * Copyright (c) 1999 Alex deVries <alex@onefishtwo.ca>
10 * Copyright (c) 1999-2000 Philipp Rumpf <prumpf@tux.org>
11 * Copyright (c) 2000 Xavier Debacker <debackex@esiee.fr>
12 * Copyright (c) 2000-2001 Thomas Marteau <marteaut@esiee.fr>
13 *
14 * HP GSC PS/2 port driver, found in PA/RISC Workstations
15 *
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file "COPYING" in the main directory of this archive
18 * for more details.
19 *
20 * TODO:
21 * - Dino testing (did HP ever shipped a machine on which this port
22 * was usable/enabled ?)
23 */
24
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/serio.h>
29 #include <linux/input.h>
30 #include <linux/interrupt.h>
31 #include <linux/spinlock.h>
32 #include <linux/delay.h>
33 #include <linux/ioport.h>
34
35 #include <asm/irq.h>
36 #include <asm/io.h>
37 #include <asm/parisc-device.h>
38
39 MODULE_AUTHOR("Laurent Canet <canetl@esiee.fr>, Thibaut Varene <varenet@parisc-linux.org>, Helge Deller <deller@gmx.de>");
40 MODULE_DESCRIPTION("HP GSC PS2 port driver");
41 MODULE_LICENSE("GPL");
42
43 #define PFX "gscps2.c: "
44
45 /*
46 * Driver constants
47 */
48
49 /* various constants */
50 #define ENABLE 1
51 #define DISABLE 0
52
53 #define GSC_DINO_OFFSET 0x0800 /* offset for DINO controller versus LASI one */
54
55 /* PS/2 IO port offsets */
56 #define GSC_ID 0x00 /* device ID offset (see: GSC_ID_XXX) */
57 #define GSC_RESET 0x00 /* reset port offset */
58 #define GSC_RCVDATA 0x04 /* receive port offset */
59 #define GSC_XMTDATA 0x04 /* transmit port offset */
60 #define GSC_CONTROL 0x08 /* see: Control register bits */
61 #define GSC_STATUS 0x0C /* see: Status register bits */
62
63 /* Control register bits */
64 #define GSC_CTRL_ENBL 0x01 /* enable interface */
65 #define GSC_CTRL_LPBXR 0x02 /* loopback operation */
66 #define GSC_CTRL_DIAG 0x20 /* directly control clock/data line */
67 #define GSC_CTRL_DATDIR 0x40 /* data line direct control */
68 #define GSC_CTRL_CLKDIR 0x80 /* clock line direct control */
69
70 /* Status register bits */
71 #define GSC_STAT_RBNE 0x01 /* Receive Buffer Not Empty */
72 #define GSC_STAT_TBNE 0x02 /* Transmit Buffer Not Empty */
73 #define GSC_STAT_TERR 0x04 /* Timeout Error */
74 #define GSC_STAT_PERR 0x08 /* Parity Error */
75 #define GSC_STAT_CMPINTR 0x10 /* Composite Interrupt = irq on any port */
76 #define GSC_STAT_DATSHD 0x40 /* Data Line Shadow */
77 #define GSC_STAT_CLKSHD 0x80 /* Clock Line Shadow */
78
79 /* IDs returned by GSC_ID port register */
80 #define GSC_ID_KEYBOARD 0 /* device ID values */
81 #define GSC_ID_MOUSE 1
82
83
84 static irqreturn_t gscps2_interrupt(int irq, void *dev);
85
86 #define BUFFER_SIZE 0x0f
87
88 /* GSC PS/2 port device struct */
89 struct gscps2port {
90 struct list_head node;
91 struct parisc_device *padev;
92 struct serio *port;
93 spinlock_t lock;
94 char __iomem *addr;
95 u8 act, append; /* position in buffer[] */
96 struct {
97 u8 data;
98 u8 str;
99 } buffer[BUFFER_SIZE+1];
100 int id;
101 };
102
103 /*
104 * Various HW level routines
105 */
106
107 #define gscps2_readb_input(x) readb((x)+GSC_RCVDATA)
108 #define gscps2_readb_control(x) readb((x)+GSC_CONTROL)
109 #define gscps2_readb_status(x) readb((x)+GSC_STATUS)
110 #define gscps2_writeb_control(x, y) writeb((x), (y)+GSC_CONTROL)
111
112
113 /*
114 * wait_TBE() - wait for Transmit Buffer Empty
115 */
116
wait_TBE(char __iomem * addr)117 static int wait_TBE(char __iomem *addr)
118 {
119 int timeout = 25000; /* device is expected to react within 250 msec */
120 while (gscps2_readb_status(addr) & GSC_STAT_TBNE) {
121 if (!--timeout)
122 return 0; /* This should not happen */
123 udelay(10);
124 }
125 return 1;
126 }
127
128
129 /*
130 * gscps2_flush() - flush the receive buffer
131 */
132
gscps2_flush(struct gscps2port * ps2port)133 static void gscps2_flush(struct gscps2port *ps2port)
134 {
135 while (gscps2_readb_status(ps2port->addr) & GSC_STAT_RBNE)
136 gscps2_readb_input(ps2port->addr);
137 ps2port->act = ps2port->append = 0;
138 }
139
140 /*
141 * gscps2_writeb_output() - write a byte to the port
142 *
143 * returns 1 on success, 0 on error
144 */
145
gscps2_writeb_output(struct gscps2port * ps2port,u8 data)146 static inline int gscps2_writeb_output(struct gscps2port *ps2port, u8 data)
147 {
148 unsigned long flags;
149 char __iomem *addr = ps2port->addr;
150
151 if (!wait_TBE(addr)) {
152 printk(KERN_DEBUG PFX "timeout - could not write byte %#x\n", data);
153 return 0;
154 }
155
156 while (gscps2_readb_status(addr) & GSC_STAT_RBNE)
157 /* wait */;
158
159 spin_lock_irqsave(&ps2port->lock, flags);
160 writeb(data, addr+GSC_XMTDATA);
161 spin_unlock_irqrestore(&ps2port->lock, flags);
162
163 /* this is ugly, but due to timing of the port it seems to be necessary. */
164 mdelay(6);
165
166 /* make sure any received data is returned as fast as possible */
167 /* this is important e.g. when we set the LEDs on the keyboard */
168 gscps2_interrupt(0, NULL);
169
170 return 1;
171 }
172
173
174 /*
175 * gscps2_enable() - enables or disables the port
176 */
177
gscps2_enable(struct gscps2port * ps2port,int enable)178 static void gscps2_enable(struct gscps2port *ps2port, int enable)
179 {
180 unsigned long flags;
181 u8 data;
182
183 /* now enable/disable the port */
184 spin_lock_irqsave(&ps2port->lock, flags);
185 gscps2_flush(ps2port);
186 data = gscps2_readb_control(ps2port->addr);
187 if (enable)
188 data |= GSC_CTRL_ENBL;
189 else
190 data &= ~GSC_CTRL_ENBL;
191 gscps2_writeb_control(data, ps2port->addr);
192 spin_unlock_irqrestore(&ps2port->lock, flags);
193 wait_TBE(ps2port->addr);
194 gscps2_flush(ps2port);
195 }
196
197 /*
198 * gscps2_reset() - resets the PS/2 port
199 */
200
gscps2_reset(struct gscps2port * ps2port)201 static void gscps2_reset(struct gscps2port *ps2port)
202 {
203 unsigned long flags;
204
205 /* reset the interface */
206 spin_lock_irqsave(&ps2port->lock, flags);
207 gscps2_flush(ps2port);
208 writeb(0xff, ps2port->addr + GSC_RESET);
209 gscps2_flush(ps2port);
210 spin_unlock_irqrestore(&ps2port->lock, flags);
211 }
212
213 static LIST_HEAD(ps2port_list);
214
215 /**
216 * gscps2_interrupt() - Interruption service routine
217 *
218 * This function reads received PS/2 bytes and processes them on
219 * all interfaces.
220 * The problematic part here is, that the keyboard and mouse PS/2 port
221 * share the same interrupt and it's not possible to send data if any
222 * one of them holds input data. To solve this problem we try to receive
223 * the data as fast as possible and handle the reporting to the upper layer
224 * later.
225 */
226
gscps2_interrupt(int irq,void * dev)227 static irqreturn_t gscps2_interrupt(int irq, void *dev)
228 {
229 struct gscps2port *ps2port;
230
231 list_for_each_entry(ps2port, &ps2port_list, node) {
232
233 unsigned long flags;
234 spin_lock_irqsave(&ps2port->lock, flags);
235
236 while ( (ps2port->buffer[ps2port->append].str =
237 gscps2_readb_status(ps2port->addr)) & GSC_STAT_RBNE ) {
238 ps2port->buffer[ps2port->append].data =
239 gscps2_readb_input(ps2port->addr);
240 ps2port->append = ((ps2port->append+1) & BUFFER_SIZE);
241 }
242
243 spin_unlock_irqrestore(&ps2port->lock, flags);
244
245 } /* list_for_each_entry */
246
247 /* all data was read from the ports - now report the data to upper layer */
248
249 list_for_each_entry(ps2port, &ps2port_list, node) {
250
251 while (ps2port->act != ps2port->append) {
252
253 unsigned int rxflags;
254 u8 data, status;
255
256 /* Did new data arrived while we read existing data ?
257 If yes, exit now and let the new irq handler start over again */
258 if (gscps2_readb_status(ps2port->addr) & GSC_STAT_CMPINTR)
259 return IRQ_HANDLED;
260
261 status = ps2port->buffer[ps2port->act].str;
262 data = ps2port->buffer[ps2port->act].data;
263
264 ps2port->act = ((ps2port->act+1) & BUFFER_SIZE);
265 rxflags = ((status & GSC_STAT_TERR) ? SERIO_TIMEOUT : 0 ) |
266 ((status & GSC_STAT_PERR) ? SERIO_PARITY : 0 );
267
268 serio_interrupt(ps2port->port, data, rxflags);
269
270 } /* while() */
271
272 } /* list_for_each_entry */
273
274 return IRQ_HANDLED;
275 }
276
277
278 /*
279 * gscps2_write() - send a byte out through the aux interface.
280 */
281
gscps2_write(struct serio * port,unsigned char data)282 static int gscps2_write(struct serio *port, unsigned char data)
283 {
284 struct gscps2port *ps2port = port->port_data;
285
286 if (!gscps2_writeb_output(ps2port, data)) {
287 printk(KERN_DEBUG PFX "sending byte %#x failed.\n", data);
288 return -1;
289 }
290 return 0;
291 }
292
293 /*
294 * gscps2_open() is called when a port is opened by the higher layer.
295 * It resets and enables the port.
296 */
297
gscps2_open(struct serio * port)298 static int gscps2_open(struct serio *port)
299 {
300 struct gscps2port *ps2port = port->port_data;
301
302 gscps2_reset(ps2port);
303
304 /* enable it */
305 gscps2_enable(ps2port, ENABLE);
306
307 gscps2_interrupt(0, NULL);
308
309 return 0;
310 }
311
312 /*
313 * gscps2_close() disables the port
314 */
315
gscps2_close(struct serio * port)316 static void gscps2_close(struct serio *port)
317 {
318 struct gscps2port *ps2port = port->port_data;
319 gscps2_enable(ps2port, DISABLE);
320 }
321
322 /**
323 * gscps2_probe() - Probes PS2 devices
324 * @return: success/error report
325 */
326
gscps2_probe(struct parisc_device * dev)327 static int __init gscps2_probe(struct parisc_device *dev)
328 {
329 struct gscps2port *ps2port;
330 struct serio *serio;
331 unsigned long hpa = dev->hpa.start;
332 int ret;
333
334 if (!dev->irq)
335 return -ENODEV;
336
337 /* Offset for DINO PS/2. Works with LASI even */
338 if (dev->id.sversion == 0x96)
339 hpa += GSC_DINO_OFFSET;
340
341 ps2port = kzalloc(sizeof(struct gscps2port), GFP_KERNEL);
342 serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
343 if (!ps2port || !serio) {
344 ret = -ENOMEM;
345 goto fail_nomem;
346 }
347
348 dev_set_drvdata(&dev->dev, ps2port);
349
350 ps2port->port = serio;
351 ps2port->padev = dev;
352 ps2port->addr = ioremap_nocache(hpa, GSC_STATUS + 4);
353 spin_lock_init(&ps2port->lock);
354
355 gscps2_reset(ps2port);
356 ps2port->id = readb(ps2port->addr + GSC_ID) & 0x0f;
357
358 snprintf(serio->name, sizeof(serio->name), "gsc-ps2-%s",
359 (ps2port->id == GSC_ID_KEYBOARD) ? "keyboard" : "mouse");
360 strlcpy(serio->phys, dev_name(&dev->dev), sizeof(serio->phys));
361 serio->id.type = SERIO_8042;
362 serio->write = gscps2_write;
363 serio->open = gscps2_open;
364 serio->close = gscps2_close;
365 serio->port_data = ps2port;
366 serio->dev.parent = &dev->dev;
367
368 ret = -EBUSY;
369 if (request_irq(dev->irq, gscps2_interrupt, IRQF_SHARED, ps2port->port->name, ps2port))
370 goto fail_miserably;
371
372 if (ps2port->id != GSC_ID_KEYBOARD && ps2port->id != GSC_ID_MOUSE) {
373 printk(KERN_WARNING PFX "Unsupported PS/2 port at 0x%08lx (id=%d) ignored\n",
374 hpa, ps2port->id);
375 ret = -ENODEV;
376 goto fail;
377 }
378
379 #if 0
380 if (!request_mem_region(hpa, GSC_STATUS + 4, ps2port->port.name))
381 goto fail;
382 #endif
383
384 printk(KERN_INFO "serio: %s port at 0x%p irq %d @ %s\n",
385 ps2port->port->name,
386 ps2port->addr,
387 ps2port->padev->irq,
388 ps2port->port->phys);
389
390 serio_register_port(ps2port->port);
391
392 list_add_tail(&ps2port->node, &ps2port_list);
393
394 return 0;
395
396 fail:
397 free_irq(dev->irq, ps2port);
398
399 fail_miserably:
400 iounmap(ps2port->addr);
401 release_mem_region(dev->hpa.start, GSC_STATUS + 4);
402
403 fail_nomem:
404 kfree(ps2port);
405 kfree(serio);
406 return ret;
407 }
408
409 /**
410 * gscps2_remove() - Removes PS2 devices
411 * @return: success/error report
412 */
413
gscps2_remove(struct parisc_device * dev)414 static int __exit gscps2_remove(struct parisc_device *dev)
415 {
416 struct gscps2port *ps2port = dev_get_drvdata(&dev->dev);
417
418 serio_unregister_port(ps2port->port);
419 free_irq(dev->irq, ps2port);
420 gscps2_flush(ps2port);
421 list_del(&ps2port->node);
422 iounmap(ps2port->addr);
423 #if 0
424 release_mem_region(dev->hpa, GSC_STATUS + 4);
425 #endif
426 dev_set_drvdata(&dev->dev, NULL);
427 kfree(ps2port);
428 return 0;
429 }
430
431
432 static const struct parisc_device_id gscps2_device_tbl[] __initconst = {
433 { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00084 }, /* LASI PS/2 */
434 #ifdef DINO_TESTED
435 { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00096 }, /* DINO PS/2 */
436 #endif
437 { 0, } /* 0 terminated list */
438 };
439 MODULE_DEVICE_TABLE(parisc, gscps2_device_tbl);
440
441 static struct parisc_driver parisc_ps2_driver __refdata = {
442 .name = "gsc_ps2",
443 .id_table = gscps2_device_tbl,
444 .probe = gscps2_probe,
445 .remove = __exit_p(gscps2_remove),
446 };
447
gscps2_init(void)448 static int __init gscps2_init(void)
449 {
450 register_parisc_driver(&parisc_ps2_driver);
451 return 0;
452 }
453
gscps2_exit(void)454 static void __exit gscps2_exit(void)
455 {
456 unregister_parisc_driver(&parisc_ps2_driver);
457 }
458
459
460 module_init(gscps2_init);
461 module_exit(gscps2_exit);
462
463
