xref: /openbmc/linux/drivers/parport/parport_gsc.c (revision 87c2ce3b)
1 /*
2  *      Low-level parallel-support for PC-style hardware integrated in the
3  *	LASI-Controller (on GSC-Bus) for HP-PARISC Workstations
4  *
5  *	This program is free software; you can redistribute it and/or modify
6  *	it under the terms of the GNU General Public License as published by
7  *      the Free Software Foundation; either version 2 of the License, or
8  *      (at your option) any later version.
9  *
10  *	(C) 1999-2001 by Helge Deller <deller@gmx.de>
11  *
12  *
13  * based on parport_pc.c by
14  * 	    Grant Guenther <grant@torque.net>
15  * 	    Phil Blundell <philb@gnu.org>
16  *          Tim Waugh <tim@cyberelk.demon.co.uk>
17  *	    Jose Renau <renau@acm.org>
18  *          David Campbell <campbell@torque.net>
19  *          Andrea Arcangeli
20  */
21 
22 #undef DEBUG	/* undef for production */
23 
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/sched.h>
27 #include <linux/delay.h>
28 #include <linux/errno.h>
29 #include <linux/interrupt.h>
30 #include <linux/ioport.h>
31 #include <linux/kernel.h>
32 #include <linux/slab.h>
33 #include <linux/pci.h>
34 #include <linux/sysctl.h>
35 
36 #include <asm/io.h>
37 #include <asm/dma.h>
38 #include <asm/uaccess.h>
39 #include <asm/superio.h>
40 
41 #include <linux/parport.h>
42 #include <asm/pdc.h>
43 #include <asm/parisc-device.h>
44 #include <asm/hardware.h>
45 #include "parport_gsc.h"
46 
47 
48 MODULE_AUTHOR("Helge Deller <deller@gmx.de>");
49 MODULE_DESCRIPTION("HP-PARISC PC-style parallel port driver");
50 MODULE_SUPPORTED_DEVICE("integrated PC-style parallel port");
51 MODULE_LICENSE("GPL");
52 
53 
54 /*
55  * Clear TIMEOUT BIT in EPP MODE
56  *
57  * This is also used in SPP detection.
58  */
59 static int clear_epp_timeout(struct parport *pb)
60 {
61 	unsigned char r;
62 
63 	if (!(parport_gsc_read_status(pb) & 0x01))
64 		return 1;
65 
66 	/* To clear timeout some chips require double read */
67 	parport_gsc_read_status(pb);
68 	r = parport_gsc_read_status(pb);
69 	parport_writeb (r | 0x01, STATUS (pb)); /* Some reset by writing 1 */
70 	parport_writeb (r & 0xfe, STATUS (pb)); /* Others by writing 0 */
71 	r = parport_gsc_read_status(pb);
72 
73 	return !(r & 0x01);
74 }
75 
76 /*
77  * Access functions.
78  *
79  * Most of these aren't static because they may be used by the
80  * parport_xxx_yyy macros.  extern __inline__ versions of several
81  * of these are in parport_gsc.h.
82  */
83 
84 static irqreturn_t parport_gsc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
85 {
86 	parport_generic_irq(irq, (struct parport *) dev_id, regs);
87 	return IRQ_HANDLED;
88 }
89 
90 void parport_gsc_init_state(struct pardevice *dev, struct parport_state *s)
91 {
92 	s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
93 }
94 
95 void parport_gsc_save_state(struct parport *p, struct parport_state *s)
96 {
97 	s->u.pc.ctr = parport_readb (CONTROL (p));
98 }
99 
100 void parport_gsc_restore_state(struct parport *p, struct parport_state *s)
101 {
102 	parport_writeb (s->u.pc.ctr, CONTROL (p));
103 }
104 
105 struct parport_operations parport_gsc_ops =
106 {
107 	.write_data	= parport_gsc_write_data,
108 	.read_data	= parport_gsc_read_data,
109 
110 	.write_control	= parport_gsc_write_control,
111 	.read_control	= parport_gsc_read_control,
112 	.frob_control	= parport_gsc_frob_control,
113 
114 	.read_status	= parport_gsc_read_status,
115 
116 	.enable_irq	= parport_gsc_enable_irq,
117 	.disable_irq	= parport_gsc_disable_irq,
118 
119 	.data_forward	= parport_gsc_data_forward,
120 	.data_reverse	= parport_gsc_data_reverse,
121 
122 	.init_state	= parport_gsc_init_state,
123 	.save_state	= parport_gsc_save_state,
124 	.restore_state	= parport_gsc_restore_state,
125 
126 	.epp_write_data	= parport_ieee1284_epp_write_data,
127 	.epp_read_data	= parport_ieee1284_epp_read_data,
128 	.epp_write_addr	= parport_ieee1284_epp_write_addr,
129 	.epp_read_addr	= parport_ieee1284_epp_read_addr,
130 
131 	.ecp_write_data	= parport_ieee1284_ecp_write_data,
132 	.ecp_read_data	= parport_ieee1284_ecp_read_data,
133 	.ecp_write_addr	= parport_ieee1284_ecp_write_addr,
134 
135 	.compat_write_data 	= parport_ieee1284_write_compat,
136 	.nibble_read_data	= parport_ieee1284_read_nibble,
137 	.byte_read_data		= parport_ieee1284_read_byte,
138 
139 	.owner		= THIS_MODULE,
140 };
141 
142 /* --- Mode detection ------------------------------------- */
143 
144 /*
145  * Checks for port existence, all ports support SPP MODE
146  */
147 static int __devinit parport_SPP_supported(struct parport *pb)
148 {
149 	unsigned char r, w;
150 
151 	/*
152 	 * first clear an eventually pending EPP timeout
153 	 * I (sailer@ife.ee.ethz.ch) have an SMSC chipset
154 	 * that does not even respond to SPP cycles if an EPP
155 	 * timeout is pending
156 	 */
157 	clear_epp_timeout(pb);
158 
159 	/* Do a simple read-write test to make sure the port exists. */
160 	w = 0xc;
161 	parport_writeb (w, CONTROL (pb));
162 
163 	/* Is there a control register that we can read from?  Some
164 	 * ports don't allow reads, so read_control just returns a
165 	 * software copy. Some ports _do_ allow reads, so bypass the
166 	 * software copy here.  In addition, some bits aren't
167 	 * writable. */
168 	r = parport_readb (CONTROL (pb));
169 	if ((r & 0xf) == w) {
170 		w = 0xe;
171 		parport_writeb (w, CONTROL (pb));
172 		r = parport_readb (CONTROL (pb));
173 		parport_writeb (0xc, CONTROL (pb));
174 		if ((r & 0xf) == w)
175 			return PARPORT_MODE_PCSPP;
176 	}
177 
178 	/* Try the data register.  The data lines aren't tri-stated at
179 	 * this stage, so we expect back what we wrote. */
180 	w = 0xaa;
181 	parport_gsc_write_data (pb, w);
182 	r = parport_gsc_read_data (pb);
183 	if (r == w) {
184 		w = 0x55;
185 		parport_gsc_write_data (pb, w);
186 		r = parport_gsc_read_data (pb);
187 		if (r == w)
188 			return PARPORT_MODE_PCSPP;
189 	}
190 
191 	return 0;
192 }
193 
194 /* Detect PS/2 support.
195  *
196  * Bit 5 (0x20) sets the PS/2 data direction; setting this high
197  * allows us to read data from the data lines.  In theory we would get back
198  * 0xff but any peripheral attached to the port may drag some or all of the
199  * lines down to zero.  So if we get back anything that isn't the contents
200  * of the data register we deem PS/2 support to be present.
201  *
202  * Some SPP ports have "half PS/2" ability - you can't turn off the line
203  * drivers, but an external peripheral with sufficiently beefy drivers of
204  * its own can overpower them and assert its own levels onto the bus, from
205  * where they can then be read back as normal.  Ports with this property
206  * and the right type of device attached are likely to fail the SPP test,
207  * (as they will appear to have stuck bits) and so the fact that they might
208  * be misdetected here is rather academic.
209  */
210 
211 static int __devinit parport_PS2_supported(struct parport *pb)
212 {
213 	int ok = 0;
214 
215 	clear_epp_timeout(pb);
216 
217 	/* try to tri-state the buffer */
218 	parport_gsc_data_reverse (pb);
219 
220 	parport_gsc_write_data(pb, 0x55);
221 	if (parport_gsc_read_data(pb) != 0x55) ok++;
222 
223 	parport_gsc_write_data(pb, 0xaa);
224 	if (parport_gsc_read_data(pb) != 0xaa) ok++;
225 
226 	/* cancel input mode */
227 	parport_gsc_data_forward (pb);
228 
229 	if (ok) {
230 		pb->modes |= PARPORT_MODE_TRISTATE;
231 	} else {
232 		struct parport_gsc_private *priv = pb->private_data;
233 		priv->ctr_writable &= ~0x20;
234 	}
235 
236 	return ok;
237 }
238 
239 
240 /* --- Initialisation code -------------------------------- */
241 
242 struct parport *__devinit parport_gsc_probe_port (unsigned long base,
243 						 unsigned long base_hi,
244 						 int irq, int dma,
245 						 struct pci_dev *dev)
246 {
247 	struct parport_gsc_private *priv;
248 	struct parport_operations *ops;
249 	struct parport tmp;
250 	struct parport *p = &tmp;
251 
252 	priv = kmalloc (sizeof (struct parport_gsc_private), GFP_KERNEL);
253 	if (!priv) {
254 		printk (KERN_DEBUG "parport (0x%lx): no memory!\n", base);
255 		return NULL;
256 	}
257 	ops = kmalloc (sizeof (struct parport_operations), GFP_KERNEL);
258 	if (!ops) {
259 		printk (KERN_DEBUG "parport (0x%lx): no memory for ops!\n",
260 			base);
261 		kfree (priv);
262 		return NULL;
263 	}
264 	memcpy (ops, &parport_gsc_ops, sizeof (struct parport_operations));
265 	priv->ctr = 0xc;
266 	priv->ctr_writable = 0xff;
267 	priv->dma_buf = 0;
268 	priv->dma_handle = 0;
269 	priv->dev = dev;
270 	p->base = base;
271 	p->base_hi = base_hi;
272 	p->irq = irq;
273 	p->dma = dma;
274 	p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;
275 	p->ops = ops;
276 	p->private_data = priv;
277 	p->physport = p;
278 	if (!parport_SPP_supported (p)) {
279 		/* No port. */
280 		kfree (priv);
281 		return NULL;
282 	}
283 	parport_PS2_supported (p);
284 
285 	if (!(p = parport_register_port(base, PARPORT_IRQ_NONE,
286 					PARPORT_DMA_NONE, ops))) {
287 		kfree (priv);
288 		kfree (ops);
289 		return NULL;
290 	}
291 
292 	p->base_hi = base_hi;
293 	p->modes = tmp.modes;
294 	p->size = (p->modes & PARPORT_MODE_EPP)?8:3;
295 	p->private_data = priv;
296 
297 	printk(KERN_INFO "%s: PC-style at 0x%lx", p->name, p->base);
298 	p->irq = irq;
299 	if (p->irq == PARPORT_IRQ_AUTO) {
300 		p->irq = PARPORT_IRQ_NONE;
301 	}
302 	if (p->irq != PARPORT_IRQ_NONE) {
303 		printk(", irq %d", p->irq);
304 
305 		if (p->dma == PARPORT_DMA_AUTO) {
306 			p->dma = PARPORT_DMA_NONE;
307 		}
308 	}
309 	if (p->dma == PARPORT_DMA_AUTO) /* To use DMA, giving the irq
310                                            is mandatory (see above) */
311 		p->dma = PARPORT_DMA_NONE;
312 
313 	printk(" [");
314 #define printmode(x) {if(p->modes&PARPORT_MODE_##x){printk("%s%s",f?",":"",#x);f++;}}
315 	{
316 		int f = 0;
317 		printmode(PCSPP);
318 		printmode(TRISTATE);
319 		printmode(COMPAT)
320 		printmode(EPP);
321 //		printmode(ECP);
322 //		printmode(DMA);
323 	}
324 #undef printmode
325 	printk("]\n");
326 
327 	if (p->irq != PARPORT_IRQ_NONE) {
328 		if (request_irq (p->irq, parport_gsc_interrupt,
329 				 0, p->name, p)) {
330 			printk (KERN_WARNING "%s: irq %d in use, "
331 				"resorting to polled operation\n",
332 				p->name, p->irq);
333 			p->irq = PARPORT_IRQ_NONE;
334 			p->dma = PARPORT_DMA_NONE;
335 		}
336 	}
337 
338 	/* Done probing.  Now put the port into a sensible start-up state. */
339 
340 	parport_gsc_write_data(p, 0);
341 	parport_gsc_data_forward (p);
342 
343 	/* Now that we've told the sharing engine about the port, and
344 	   found out its characteristics, let the high-level drivers
345 	   know about it. */
346 	parport_announce_port (p);
347 
348 	return p;
349 }
350 
351 
352 #define PARPORT_GSC_OFFSET 0x800
353 
354 static int __initdata parport_count;
355 
356 static int __devinit parport_init_chip(struct parisc_device *dev)
357 {
358 	struct parport *p;
359 	unsigned long port;
360 
361 	if (!dev->irq) {
362 		printk(KERN_WARNING "IRQ not found for parallel device at 0x%lx\n",
363 			dev->hpa.start);
364 		return -ENODEV;
365 	}
366 
367 	port = dev->hpa.start + PARPORT_GSC_OFFSET;
368 
369 	/* some older machines with ASP-chip don't support
370 	 * the enhanced parport modes.
371 	 */
372 	if (boot_cpu_data.cpu_type > pcxt && !pdc_add_valid(port+4)) {
373 
374 		/* Initialize bidirectional-mode (0x10) & data-tranfer-mode #1 (0x20) */
375 		printk("%s: initialize bidirectional-mode.\n", __FUNCTION__);
376 		parport_writeb ( (0x10 + 0x20), port + 4);
377 
378 	} else {
379 		printk("%s: enhanced parport-modes not supported.\n", __FUNCTION__);
380 	}
381 
382 	p = parport_gsc_probe_port(port, 0, dev->irq,
383 			/* PARPORT_IRQ_NONE */ PARPORT_DMA_NONE, NULL);
384 	if (p)
385 		parport_count++;
386 	dev->dev.driver_data = p;
387 
388 	return 0;
389 }
390 
391 static int __devexit parport_remove_chip(struct parisc_device *dev)
392 {
393 	struct parport *p = dev->dev.driver_data;
394 	if (p) {
395 		struct parport_gsc_private *priv = p->private_data;
396 		struct parport_operations *ops = p->ops;
397 		parport_remove_port(p);
398 		if (p->dma != PARPORT_DMA_NONE)
399 			free_dma(p->dma);
400 		if (p->irq != PARPORT_IRQ_NONE)
401 			free_irq(p->irq, p);
402 		if (priv->dma_buf)
403 			pci_free_consistent(priv->dev, PAGE_SIZE,
404 					    priv->dma_buf,
405 					    priv->dma_handle);
406 		kfree (p->private_data);
407 		parport_put_port(p);
408 		kfree (ops); /* hope no-one cached it */
409 	}
410 	return 0;
411 }
412 
413 static struct parisc_device_id parport_tbl[] = {
414 	{ HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x74 },
415 	{ 0, }
416 };
417 
418 MODULE_DEVICE_TABLE(parisc, parport_tbl);
419 
420 static struct parisc_driver parport_driver = {
421 	.name		= "Parallel",
422 	.id_table	= parport_tbl,
423 	.probe		= parport_init_chip,
424 	.remove		= __devexit_p(parport_remove_chip),
425 };
426 
427 int __devinit parport_gsc_init(void)
428 {
429 	return register_parisc_driver(&parport_driver);
430 }
431 
432 static void __devexit parport_gsc_exit(void)
433 {
434 	unregister_parisc_driver(&parport_driver);
435 }
436 
437 module_init(parport_gsc_init);
438 module_exit(parport_gsc_exit);
439