1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Low-level parallel-support for PC-style hardware integrated in the |
4 | * LASI-Controller (on GSC-Bus) for HP-PARISC Workstations |
5 | * |
6 | * (C) 1999-2001 by Helge Deller <deller@gmx.de> |
7 | * |
8 | * based on parport_pc.c by |
9 | * Grant Guenther <grant@torque.net> |
10 | * Phil Blundell <philb@gnu.org> |
11 | * Tim Waugh <tim@cyberelk.demon.co.uk> |
12 | * Jose Renau <renau@acm.org> |
13 | * David Campbell |
14 | * Andrea Arcangeli |
15 | */ |
16 | |
17 | #undef DEBUG /* undef for production */ |
18 | |
19 | #include <linux/module.h> |
20 | #include <linux/init.h> |
21 | #include <linux/delay.h> |
22 | #include <linux/errno.h> |
23 | #include <linux/interrupt.h> |
24 | #include <linux/ioport.h> |
25 | #include <linux/kernel.h> |
26 | #include <linux/slab.h> |
27 | #include <linux/pci.h> |
28 | #include <linux/sysctl.h> |
29 | |
30 | #include <asm/io.h> |
31 | #include <linux/uaccess.h> |
32 | #include <asm/superio.h> |
33 | |
34 | #include <linux/parport.h> |
35 | #include <asm/pdc.h> |
36 | #include <asm/parisc-device.h> |
37 | #include <asm/hardware.h> |
38 | #include "parport_gsc.h" |
39 | |
40 | |
41 | MODULE_AUTHOR("Helge Deller <deller@gmx.de>" ); |
42 | MODULE_DESCRIPTION("HP-PARISC PC-style parallel port driver" ); |
43 | MODULE_LICENSE("GPL" ); |
44 | |
45 | |
46 | /* |
47 | * Clear TIMEOUT BIT in EPP MODE |
48 | * |
49 | * This is also used in SPP detection. |
50 | */ |
51 | static int clear_epp_timeout(struct parport *pb) |
52 | { |
53 | unsigned char r; |
54 | |
55 | if (!(parport_gsc_read_status(p: pb) & 0x01)) |
56 | return 1; |
57 | |
58 | /* To clear timeout some chips require double read */ |
59 | parport_gsc_read_status(p: pb); |
60 | r = parport_gsc_read_status(p: pb); |
61 | parport_writeb (r | 0x01, STATUS (pb)); /* Some reset by writing 1 */ |
62 | parport_writeb (r & 0xfe, STATUS (pb)); /* Others by writing 0 */ |
63 | r = parport_gsc_read_status(p: pb); |
64 | |
65 | return !(r & 0x01); |
66 | } |
67 | |
68 | /* |
69 | * Access functions. |
70 | * |
71 | * Most of these aren't static because they may be used by the |
72 | * parport_xxx_yyy macros. extern __inline__ versions of several |
73 | * of these are in parport_gsc.h. |
74 | */ |
75 | |
76 | void parport_gsc_init_state(struct pardevice *dev, struct parport_state *s) |
77 | { |
78 | s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0); |
79 | } |
80 | |
81 | void parport_gsc_save_state(struct parport *p, struct parport_state *s) |
82 | { |
83 | s->u.pc.ctr = parport_readb (CONTROL (p)); |
84 | } |
85 | |
86 | void parport_gsc_restore_state(struct parport *p, struct parport_state *s) |
87 | { |
88 | parport_writeb (s->u.pc.ctr, CONTROL (p)); |
89 | } |
90 | |
91 | struct parport_operations parport_gsc_ops = |
92 | { |
93 | .write_data = parport_gsc_write_data, |
94 | .read_data = parport_gsc_read_data, |
95 | |
96 | .write_control = parport_gsc_write_control, |
97 | .read_control = parport_gsc_read_control, |
98 | .frob_control = parport_gsc_frob_control, |
99 | |
100 | .read_status = parport_gsc_read_status, |
101 | |
102 | .enable_irq = parport_gsc_enable_irq, |
103 | .disable_irq = parport_gsc_disable_irq, |
104 | |
105 | .data_forward = parport_gsc_data_forward, |
106 | .data_reverse = parport_gsc_data_reverse, |
107 | |
108 | .init_state = parport_gsc_init_state, |
109 | .save_state = parport_gsc_save_state, |
110 | .restore_state = parport_gsc_restore_state, |
111 | |
112 | .epp_write_data = parport_ieee1284_epp_write_data, |
113 | .epp_read_data = parport_ieee1284_epp_read_data, |
114 | .epp_write_addr = parport_ieee1284_epp_write_addr, |
115 | .epp_read_addr = parport_ieee1284_epp_read_addr, |
116 | |
117 | .ecp_write_data = parport_ieee1284_ecp_write_data, |
118 | .ecp_read_data = parport_ieee1284_ecp_read_data, |
119 | .ecp_write_addr = parport_ieee1284_ecp_write_addr, |
120 | |
121 | .compat_write_data = parport_ieee1284_write_compat, |
122 | .nibble_read_data = parport_ieee1284_read_nibble, |
123 | .byte_read_data = parport_ieee1284_read_byte, |
124 | |
125 | .owner = THIS_MODULE, |
126 | }; |
127 | |
128 | /* --- Mode detection ------------------------------------- */ |
129 | |
130 | /* |
131 | * Checks for port existence, all ports support SPP MODE |
132 | */ |
133 | static int parport_SPP_supported(struct parport *pb) |
134 | { |
135 | unsigned char r, w; |
136 | |
137 | /* |
138 | * first clear an eventually pending EPP timeout |
139 | * I (sailer@ife.ee.ethz.ch) have an SMSC chipset |
140 | * that does not even respond to SPP cycles if an EPP |
141 | * timeout is pending |
142 | */ |
143 | clear_epp_timeout(pb); |
144 | |
145 | /* Do a simple read-write test to make sure the port exists. */ |
146 | w = 0xc; |
147 | parport_writeb (w, CONTROL (pb)); |
148 | |
149 | /* Is there a control register that we can read from? Some |
150 | * ports don't allow reads, so read_control just returns a |
151 | * software copy. Some ports _do_ allow reads, so bypass the |
152 | * software copy here. In addition, some bits aren't |
153 | * writable. */ |
154 | r = parport_readb (CONTROL (pb)); |
155 | if ((r & 0xf) == w) { |
156 | w = 0xe; |
157 | parport_writeb (w, CONTROL (pb)); |
158 | r = parport_readb (CONTROL (pb)); |
159 | parport_writeb (0xc, CONTROL (pb)); |
160 | if ((r & 0xf) == w) |
161 | return PARPORT_MODE_PCSPP; |
162 | } |
163 | |
164 | /* Try the data register. The data lines aren't tri-stated at |
165 | * this stage, so we expect back what we wrote. */ |
166 | w = 0xaa; |
167 | parport_gsc_write_data (p: pb, d: w); |
168 | r = parport_gsc_read_data (p: pb); |
169 | if (r == w) { |
170 | w = 0x55; |
171 | parport_gsc_write_data (p: pb, d: w); |
172 | r = parport_gsc_read_data (p: pb); |
173 | if (r == w) |
174 | return PARPORT_MODE_PCSPP; |
175 | } |
176 | |
177 | return 0; |
178 | } |
179 | |
180 | /* Detect PS/2 support. |
181 | * |
182 | * Bit 5 (0x20) sets the PS/2 data direction; setting this high |
183 | * allows us to read data from the data lines. In theory we would get back |
184 | * 0xff but any peripheral attached to the port may drag some or all of the |
185 | * lines down to zero. So if we get back anything that isn't the contents |
186 | * of the data register we deem PS/2 support to be present. |
187 | * |
188 | * Some SPP ports have "half PS/2" ability - you can't turn off the line |
189 | * drivers, but an external peripheral with sufficiently beefy drivers of |
190 | * its own can overpower them and assert its own levels onto the bus, from |
191 | * where they can then be read back as normal. Ports with this property |
192 | * and the right type of device attached are likely to fail the SPP test, |
193 | * (as they will appear to have stuck bits) and so the fact that they might |
194 | * be misdetected here is rather academic. |
195 | */ |
196 | |
197 | static int parport_PS2_supported(struct parport *pb) |
198 | { |
199 | int ok = 0; |
200 | |
201 | clear_epp_timeout(pb); |
202 | |
203 | /* try to tri-state the buffer */ |
204 | parport_gsc_data_reverse (p: pb); |
205 | |
206 | parport_gsc_write_data(p: pb, d: 0x55); |
207 | if (parport_gsc_read_data(p: pb) != 0x55) ok++; |
208 | |
209 | parport_gsc_write_data(p: pb, d: 0xaa); |
210 | if (parport_gsc_read_data(p: pb) != 0xaa) ok++; |
211 | |
212 | /* cancel input mode */ |
213 | parport_gsc_data_forward (p: pb); |
214 | |
215 | if (ok) { |
216 | pb->modes |= PARPORT_MODE_TRISTATE; |
217 | } else { |
218 | struct parport_gsc_private *priv = pb->private_data; |
219 | priv->ctr_writable &= ~0x20; |
220 | } |
221 | |
222 | return ok; |
223 | } |
224 | |
225 | |
226 | /* --- Initialisation code -------------------------------- */ |
227 | |
228 | static struct parport *parport_gsc_probe_port(unsigned long base, |
229 | unsigned long base_hi, int irq, |
230 | struct parisc_device *padev) |
231 | { |
232 | struct parport_gsc_private *priv; |
233 | struct parport_operations *ops; |
234 | struct parport tmp; |
235 | struct parport *p = &tmp; |
236 | |
237 | priv = kzalloc (size: sizeof (struct parport_gsc_private), GFP_KERNEL); |
238 | if (!priv) { |
239 | printk(KERN_DEBUG "parport (0x%lx): no memory!\n" , base); |
240 | return NULL; |
241 | } |
242 | ops = kmemdup(p: &parport_gsc_ops, size: sizeof(struct parport_operations), |
243 | GFP_KERNEL); |
244 | if (!ops) { |
245 | printk(KERN_DEBUG "parport (0x%lx): no memory for ops!\n" , |
246 | base); |
247 | kfree (objp: priv); |
248 | return NULL; |
249 | } |
250 | priv->ctr = 0xc; |
251 | priv->ctr_writable = 0xff; |
252 | p->base = base; |
253 | p->base_hi = base_hi; |
254 | p->irq = irq; |
255 | p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT; |
256 | p->ops = ops; |
257 | p->private_data = priv; |
258 | p->physport = p; |
259 | if (!parport_SPP_supported (pb: p)) { |
260 | /* No port. */ |
261 | kfree (objp: priv); |
262 | kfree(objp: ops); |
263 | return NULL; |
264 | } |
265 | parport_PS2_supported (pb: p); |
266 | |
267 | if (!(p = parport_register_port(base, PARPORT_IRQ_NONE, |
268 | PARPORT_DMA_NONE, ops))) { |
269 | kfree (objp: priv); |
270 | kfree (objp: ops); |
271 | return NULL; |
272 | } |
273 | |
274 | p->dev = &padev->dev; |
275 | p->base_hi = base_hi; |
276 | p->modes = tmp.modes; |
277 | p->size = (p->modes & PARPORT_MODE_EPP)?8:3; |
278 | p->private_data = priv; |
279 | |
280 | pr_info("%s: PC-style at 0x%lx" , p->name, p->base); |
281 | p->irq = irq; |
282 | if (p->irq == PARPORT_IRQ_AUTO) { |
283 | p->irq = PARPORT_IRQ_NONE; |
284 | } |
285 | if (p->irq != PARPORT_IRQ_NONE) |
286 | pr_cont(", irq %d" , p->irq); |
287 | |
288 | pr_cont(" [" ); |
289 | #define printmode(x) \ |
290 | do { \ |
291 | if (p->modes & PARPORT_MODE_##x) \ |
292 | pr_cont("%s%s", f++ ? "," : "", #x); \ |
293 | } while (0) |
294 | { |
295 | int f = 0; |
296 | printmode(PCSPP); |
297 | printmode(TRISTATE); |
298 | printmode(COMPAT); |
299 | printmode(EPP); |
300 | // printmode(ECP); |
301 | // printmode(DMA); |
302 | } |
303 | #undef printmode |
304 | pr_cont("]\n" ); |
305 | |
306 | if (p->irq != PARPORT_IRQ_NONE) { |
307 | if (request_irq (irq: p->irq, handler: parport_irq_handler, |
308 | flags: 0, name: p->name, dev: p)) { |
309 | pr_warn("%s: irq %d in use, resorting to polled operation\n" , |
310 | p->name, p->irq); |
311 | p->irq = PARPORT_IRQ_NONE; |
312 | } |
313 | } |
314 | |
315 | /* Done probing. Now put the port into a sensible start-up state. */ |
316 | |
317 | parport_gsc_write_data(p, d: 0); |
318 | parport_gsc_data_forward (p); |
319 | |
320 | /* Now that we've told the sharing engine about the port, and |
321 | found out its characteristics, let the high-level drivers |
322 | know about it. */ |
323 | parport_announce_port (port: p); |
324 | |
325 | return p; |
326 | } |
327 | |
328 | |
329 | #define PARPORT_GSC_OFFSET 0x800 |
330 | |
331 | static int parport_count; |
332 | |
333 | static int __init parport_init_chip(struct parisc_device *dev) |
334 | { |
335 | struct parport *p; |
336 | unsigned long port; |
337 | |
338 | if (!dev->irq) { |
339 | pr_warn("IRQ not found for parallel device at 0x%llx\n" , |
340 | (unsigned long long)dev->hpa.start); |
341 | return -ENODEV; |
342 | } |
343 | |
344 | port = dev->hpa.start + PARPORT_GSC_OFFSET; |
345 | |
346 | /* some older machines with ASP-chip don't support |
347 | * the enhanced parport modes. |
348 | */ |
349 | if (boot_cpu_data.cpu_type > pcxt && !pdc_add_valid(port+4)) { |
350 | |
351 | /* Initialize bidirectional-mode (0x10) & data-tranfer-mode #1 (0x20) */ |
352 | pr_info("%s: initialize bidirectional-mode\n" , __func__); |
353 | parport_writeb ( (0x10 + 0x20), port + 4); |
354 | |
355 | } else { |
356 | pr_info("%s: enhanced parport-modes not supported\n" , __func__); |
357 | } |
358 | |
359 | p = parport_gsc_probe_port(base: port, base_hi: 0, irq: dev->irq, padev: dev); |
360 | if (p) |
361 | parport_count++; |
362 | dev_set_drvdata(dev: &dev->dev, data: p); |
363 | |
364 | return 0; |
365 | } |
366 | |
367 | static void __exit parport_remove_chip(struct parisc_device *dev) |
368 | { |
369 | struct parport *p = dev_get_drvdata(dev: &dev->dev); |
370 | if (p) { |
371 | struct parport_operations *ops = p->ops; |
372 | parport_remove_port(port: p); |
373 | if (p->irq != PARPORT_IRQ_NONE) |
374 | free_irq(p->irq, p); |
375 | kfree (objp: p->private_data); |
376 | parport_put_port(p); |
377 | kfree (objp: ops); /* hope no-one cached it */ |
378 | } |
379 | } |
380 | |
381 | static const struct parisc_device_id parport_tbl[] __initconst = { |
382 | { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x74 }, |
383 | { 0, } |
384 | }; |
385 | |
386 | MODULE_DEVICE_TABLE(parisc, parport_tbl); |
387 | |
388 | static struct parisc_driver parport_driver __refdata = { |
389 | .name = "Parallel" , |
390 | .id_table = parport_tbl, |
391 | .probe = parport_init_chip, |
392 | .remove = __exit_p(parport_remove_chip), |
393 | }; |
394 | |
395 | int parport_gsc_init(void) |
396 | { |
397 | return register_parisc_driver(&parport_driver); |
398 | } |
399 | |
400 | static void parport_gsc_exit(void) |
401 | { |
402 | unregister_parisc_driver(&parport_driver); |
403 | } |
404 | |
405 | module_init(parport_gsc_init); |
406 | module_exit(parport_gsc_exit); |
407 | |