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1/*
2 * IEEE 1284.3 Parallel port daisy chain and multiplexor code
3 *
4 * Copyright (C) 1999, 2000 Tim Waugh <tim@cyberelk.demon.co.uk>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 * ??-12-1998: Initial implementation.
12 * 31-01-1999: Make port-cloning transparent.
13 * 13-02-1999: Move DeviceID technique from parport_probe.
14 * 13-03-1999: Get DeviceID from non-IEEE 1284.3 devices too.
15 * 22-02-2000: Count devices that are actually detected.
16 *
17 * Any part of this program may be used in documents licensed under
18 * the GNU Free Documentation License, Version 1.1 or any later version
19 * published by the Free Software Foundation.
20 */
21
22#include <linux/module.h>
23#include <linux/parport.h>
24#include <linux/delay.h>
25#include <linux/slab.h>
26#include <linux/sched.h>
27
28#include <asm/current.h>
29#include <asm/uaccess.h>
30
31#undef DEBUG
32
33#ifdef DEBUG
34#define DPRINTK(stuff...) printk(stuff)
35#else
36#define DPRINTK(stuff...)
37#endif
38
39static struct daisydev {
40 struct daisydev *next;
41 struct parport *port;
42 int daisy;
43 int devnum;
44} *topology = NULL;
45static DEFINE_SPINLOCK(topology_lock);
46
47static int numdevs = 0;
48
49/* Forward-declaration of lower-level functions. */
50static int mux_present(struct parport *port);
51static int num_mux_ports(struct parport *port);
52static int select_port(struct parport *port);
53static int assign_addrs(struct parport *port);
54
55/* Add a device to the discovered topology. */
56static void add_dev(int devnum, struct parport *port, int daisy)
57{
58 struct daisydev *newdev, **p;
59 newdev = kmalloc(sizeof(struct daisydev), GFP_KERNEL);
60 if (newdev) {
61 newdev->port = port;
62 newdev->daisy = daisy;
63 newdev->devnum = devnum;
64 spin_lock(&topology_lock);
65 for (p = &topology; *p && (*p)->devnum<devnum; p = &(*p)->next)
66 ;
67 newdev->next = *p;
68 *p = newdev;
69 spin_unlock(&topology_lock);
70 }
71}
72
73/* Clone a parport (actually, make an alias). */
74static struct parport *clone_parport(struct parport *real, int muxport)
75{
76 struct parport *extra = parport_register_port(real->base,
77 real->irq,
78 real->dma,
79 real->ops);
80 if (extra) {
81 extra->portnum = real->portnum;
82 extra->physport = real;
83 extra->muxport = muxport;
84 real->slaves[muxport-1] = extra;
85 }
86
87 return extra;
88}
89
90/* Discover the IEEE1284.3 topology on a port -- muxes and daisy chains.
91 * Return value is number of devices actually detected. */
92int parport_daisy_init(struct parport *port)
93{
94 int detected = 0;
95 char *deviceid;
96 static const char *th[] = { /*0*/"th", "st", "nd", "rd", "th" };
97 int num_ports;
98 int i;
99 int last_try = 0;
100
101again:
102 /* Because this is called before any other devices exist,
103 * we don't have to claim exclusive access. */
104
105 /* If mux present on normal port, need to create new
106 * parports for each extra port. */
107 if (port->muxport < 0 && mux_present(port) &&
108 /* don't be fooled: a mux must have 2 or 4 ports. */
109 ((num_ports = num_mux_ports(port)) == 2 || num_ports == 4)) {
110 /* Leave original as port zero. */
111 port->muxport = 0;
112 printk(KERN_INFO
113 "%s: 1st (default) port of %d-way multiplexor\n",
114 port->name, num_ports);
115 for (i = 1; i < num_ports; i++) {
116 /* Clone the port. */
117 struct parport *extra = clone_parport(port, i);
118 if (!extra) {
119 if (signal_pending(current))
120 break;
121
122 schedule();
123 continue;
124 }
125
126 printk(KERN_INFO
127 "%s: %d%s port of %d-way multiplexor on %s\n",
128 extra->name, i + 1, th[i + 1], num_ports,
129 port->name);
130
131 /* Analyse that port too. We won't recurse
132 forever because of the 'port->muxport < 0'
133 test above. */
134 parport_daisy_init(extra);
135 }
136 }
137
138 if (port->muxport >= 0)
139 select_port(port);
140
141 parport_daisy_deselect_all(port);
142 detected += assign_addrs(port);
143
144 /* Count the potential legacy device at the end. */
145 add_dev(numdevs++, port, -1);
146
147 /* Find out the legacy device's IEEE 1284 device ID. */
148 deviceid = kmalloc(1024, GFP_KERNEL);
149 if (deviceid) {
150 if (parport_device_id(numdevs - 1, deviceid, 1024) > 2)
151 detected++;
152
153 kfree(deviceid);
154 }
155
156 if (!detected && !last_try) {
157 /* No devices were detected. Perhaps they are in some
158 funny state; let's try to reset them and see if
159 they wake up. */
160 parport_daisy_fini(port);
161 parport_write_control(port, PARPORT_CONTROL_SELECT);
162 udelay(50);
163 parport_write_control(port,
164 PARPORT_CONTROL_SELECT |
165 PARPORT_CONTROL_INIT);
166 udelay(50);
167 last_try = 1;
168 goto again;
169 }
170
171 return detected;
172}
173
174/* Forget about devices on a physical port. */
175void parport_daisy_fini(struct parport *port)
176{
177 struct daisydev **p;
178
179 spin_lock(&topology_lock);
180 p = &topology;
181 while (*p) {
182 struct daisydev *dev = *p;
183 if (dev->port != port) {
184 p = &dev->next;
185 continue;
186 }
187 *p = dev->next;
188 kfree(dev);
189 }
190
191 /* Gaps in the numbering could be handled better. How should
192 someone enumerate through all IEEE1284.3 devices in the
193 topology?. */
194 if (!topology) numdevs = 0;
195 spin_unlock(&topology_lock);
196 return;
197}
198
199/**
200 * parport_open - find a device by canonical device number
201 * @devnum: canonical device number
202 * @name: name to associate with the device
203 *
204 * This function is similar to parport_register_device(), except
205 * that it locates a device by its number rather than by the port
206 * it is attached to.
207 *
208 * All parameters except for @devnum are the same as for
209 * parport_register_device(). The return value is the same as
210 * for parport_register_device().
211 **/
212
213struct pardevice *parport_open(int devnum, const char *name)
214{
215 struct daisydev *p = topology;
216 struct parport *port;
217 struct pardevice *dev;
218 int daisy;
219
220 spin_lock(&topology_lock);
221 while (p && p->devnum != devnum)
222 p = p->next;
223
224 if (!p) {
225 spin_unlock(&topology_lock);
226 return NULL;
227 }
228
229 daisy = p->daisy;
230 port = parport_get_port(p->port);
231 spin_unlock(&topology_lock);
232
233 dev = parport_register_device(port, name, NULL, NULL, NULL, 0, NULL);
234 parport_put_port(port);
235 if (!dev)
236 return NULL;
237
238 dev->daisy = daisy;
239
240 /* Check that there really is a device to select. */
241 if (daisy >= 0) {
242 int selected;
243 parport_claim_or_block(dev);
244 selected = port->daisy;
245 parport_release(dev);
246
247 if (selected != daisy) {
248 /* No corresponding device. */
249 parport_unregister_device(dev);
250 return NULL;
251 }
252 }
253
254 return dev;
255}
256
257/**
258 * parport_close - close a device opened with parport_open()
259 * @dev: device to close
260 *
261 * This is to parport_open() as parport_unregister_device() is to
262 * parport_register_device().
263 **/
264
265void parport_close(struct pardevice *dev)
266{
267 parport_unregister_device(dev);
268}
269
270/* Send a daisy-chain-style CPP command packet. */
271static int cpp_daisy(struct parport *port, int cmd)
272{
273 unsigned char s;
274
275 parport_data_forward(port);
276 parport_write_data(port, 0xaa); udelay(2);
277 parport_write_data(port, 0x55); udelay(2);
278 parport_write_data(port, 0x00); udelay(2);
279 parport_write_data(port, 0xff); udelay(2);
280 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
281 | PARPORT_STATUS_PAPEROUT
282 | PARPORT_STATUS_SELECT
283 | PARPORT_STATUS_ERROR);
284 if (s != (PARPORT_STATUS_BUSY
285 | PARPORT_STATUS_PAPEROUT
286 | PARPORT_STATUS_SELECT
287 | PARPORT_STATUS_ERROR)) {
288 DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff(%02x)\n",
289 port->name, s);
290 return -ENXIO;
291 }
292
293 parport_write_data(port, 0x87); udelay(2);
294 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
295 | PARPORT_STATUS_PAPEROUT
296 | PARPORT_STATUS_SELECT
297 | PARPORT_STATUS_ERROR);
298 if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
299 DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff87(%02x)\n",
300 port->name, s);
301 return -ENXIO;
302 }
303
304 parport_write_data(port, 0x78); udelay(2);
305 parport_write_data(port, cmd); udelay(2);
306 parport_frob_control(port,
307 PARPORT_CONTROL_STROBE,
308 PARPORT_CONTROL_STROBE);
309 udelay(1);
310 s = parport_read_status(port);
311 parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
312 udelay(1);
313 parport_write_data(port, 0xff); udelay(2);
314
315 return s;
316}
317
318/* Send a mux-style CPP command packet. */
319static int cpp_mux(struct parport *port, int cmd)
320{
321 unsigned char s;
322 int rc;
323
324 parport_data_forward(port);
325 parport_write_data(port, 0xaa); udelay(2);
326 parport_write_data(port, 0x55); udelay(2);
327 parport_write_data(port, 0xf0); udelay(2);
328 parport_write_data(port, 0x0f); udelay(2);
329 parport_write_data(port, 0x52); udelay(2);
330 parport_write_data(port, 0xad); udelay(2);
331 parport_write_data(port, cmd); udelay(2);
332
333 s = parport_read_status(port);
334 if (!(s & PARPORT_STATUS_ACK)) {
335 DPRINTK(KERN_DEBUG "%s: cpp_mux: aa55f00f52ad%02x(%02x)\n",
336 port->name, cmd, s);
337 return -EIO;
338 }
339
340 rc = (((s & PARPORT_STATUS_SELECT ? 1 : 0) << 0) |
341 ((s & PARPORT_STATUS_PAPEROUT ? 1 : 0) << 1) |
342 ((s & PARPORT_STATUS_BUSY ? 0 : 1) << 2) |
343 ((s & PARPORT_STATUS_ERROR ? 0 : 1) << 3));
344
345 return rc;
346}
347
348void parport_daisy_deselect_all(struct parport *port)
349{
350 cpp_daisy(port, 0x30);
351}
352
353int parport_daisy_select(struct parport *port, int daisy, int mode)
354{
355 switch (mode)
356 {
357 // For these modes we should switch to EPP mode:
358 case IEEE1284_MODE_EPP:
359 case IEEE1284_MODE_EPPSL:
360 case IEEE1284_MODE_EPPSWE:
361 return !(cpp_daisy(port, 0x20 + daisy) &
362 PARPORT_STATUS_ERROR);
363
364 // For these modes we should switch to ECP mode:
365 case IEEE1284_MODE_ECP:
366 case IEEE1284_MODE_ECPRLE:
367 case IEEE1284_MODE_ECPSWE:
368 return !(cpp_daisy(port, 0xd0 + daisy) &
369 PARPORT_STATUS_ERROR);
370
371 // Nothing was told for BECP in Daisy chain specification.
372 // May be it's wise to use ECP?
373 case IEEE1284_MODE_BECP:
374 // Others use compat mode
375 case IEEE1284_MODE_NIBBLE:
376 case IEEE1284_MODE_BYTE:
377 case IEEE1284_MODE_COMPAT:
378 default:
379 return !(cpp_daisy(port, 0xe0 + daisy) &
380 PARPORT_STATUS_ERROR);
381 }
382}
383
384static int mux_present(struct parport *port)
385{
386 return cpp_mux(port, 0x51) == 3;
387}
388
389static int num_mux_ports(struct parport *port)
390{
391 return cpp_mux(port, 0x58);
392}
393
394static int select_port(struct parport *port)
395{
396 int muxport = port->muxport;
397 return cpp_mux(port, 0x60 + muxport) == muxport;
398}
399
400static int assign_addrs(struct parport *port)
401{
402 unsigned char s;
403 unsigned char daisy;
404 int thisdev = numdevs;
405 int detected;
406 char *deviceid;
407
408 parport_data_forward(port);
409 parport_write_data(port, 0xaa); udelay(2);
410 parport_write_data(port, 0x55); udelay(2);
411 parport_write_data(port, 0x00); udelay(2);
412 parport_write_data(port, 0xff); udelay(2);
413 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
414 | PARPORT_STATUS_PAPEROUT
415 | PARPORT_STATUS_SELECT
416 | PARPORT_STATUS_ERROR);
417 if (s != (PARPORT_STATUS_BUSY
418 | PARPORT_STATUS_PAPEROUT
419 | PARPORT_STATUS_SELECT
420 | PARPORT_STATUS_ERROR)) {
421 DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff(%02x)\n",
422 port->name, s);
423 return 0;
424 }
425
426 parport_write_data(port, 0x87); udelay(2);
427 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
428 | PARPORT_STATUS_PAPEROUT
429 | PARPORT_STATUS_SELECT
430 | PARPORT_STATUS_ERROR);
431 if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
432 DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff87(%02x)\n",
433 port->name, s);
434 return 0;
435 }
436
437 parport_write_data(port, 0x78); udelay(2);
438 s = parport_read_status(port);
439
440 for (daisy = 0;
441 (s & (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT))
442 == (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT)
443 && daisy < 4;
444 ++daisy) {
445 parport_write_data(port, daisy);
446 udelay(2);
447 parport_frob_control(port,
448 PARPORT_CONTROL_STROBE,
449 PARPORT_CONTROL_STROBE);
450 udelay(1);
451 parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
452 udelay(1);
453
454 add_dev(numdevs++, port, daisy);
455
456 /* See if this device thought it was the last in the
457 * chain. */
458 if (!(s & PARPORT_STATUS_BUSY))
459 break;
460
461 /* We are seeing pass through status now. We see
462 last_dev from next device or if last_dev does not
463 work status lines from some non-daisy chain
464 device. */
465 s = parport_read_status(port);
466 }
467
468 parport_write_data(port, 0xff); udelay(2);
469 detected = numdevs - thisdev;
470 DPRINTK(KERN_DEBUG "%s: Found %d daisy-chained devices\n", port->name,
471 detected);
472
473 /* Ask the new devices to introduce themselves. */
474 deviceid = kmalloc(1024, GFP_KERNEL);
475 if (!deviceid) return 0;
476
477 for (daisy = 0; thisdev < numdevs; thisdev++, daisy++)
478 parport_device_id(thisdev, deviceid, 1024);
479
480 kfree(deviceid);
481 return detected;
482}
1/*
2 * IEEE 1284.3 Parallel port daisy chain and multiplexor code
3 *
4 * Copyright (C) 1999, 2000 Tim Waugh <tim@cyberelk.demon.co.uk>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 * ??-12-1998: Initial implementation.
12 * 31-01-1999: Make port-cloning transparent.
13 * 13-02-1999: Move DeviceID technique from parport_probe.
14 * 13-03-1999: Get DeviceID from non-IEEE 1284.3 devices too.
15 * 22-02-2000: Count devices that are actually detected.
16 *
17 * Any part of this program may be used in documents licensed under
18 * the GNU Free Documentation License, Version 1.1 or any later version
19 * published by the Free Software Foundation.
20 */
21
22#include <linux/module.h>
23#include <linux/parport.h>
24#include <linux/delay.h>
25#include <linux/slab.h>
26#include <linux/sched/signal.h>
27
28#include <asm/current.h>
29#include <linux/uaccess.h>
30
31#undef DEBUG
32
33static struct daisydev {
34 struct daisydev *next;
35 struct parport *port;
36 int daisy;
37 int devnum;
38} *topology = NULL;
39static DEFINE_SPINLOCK(topology_lock);
40
41static int numdevs;
42static bool daisy_init_done;
43
44/* Forward-declaration of lower-level functions. */
45static int mux_present(struct parport *port);
46static int num_mux_ports(struct parport *port);
47static int select_port(struct parport *port);
48static int assign_addrs(struct parport *port);
49
50/* Add a device to the discovered topology. */
51static void add_dev(int devnum, struct parport *port, int daisy)
52{
53 struct daisydev *newdev, **p;
54 newdev = kmalloc(sizeof(struct daisydev), GFP_KERNEL);
55 if (newdev) {
56 newdev->port = port;
57 newdev->daisy = daisy;
58 newdev->devnum = devnum;
59 spin_lock(&topology_lock);
60 for (p = &topology; *p && (*p)->devnum<devnum; p = &(*p)->next)
61 ;
62 newdev->next = *p;
63 *p = newdev;
64 spin_unlock(&topology_lock);
65 }
66}
67
68/* Clone a parport (actually, make an alias). */
69static struct parport *clone_parport(struct parport *real, int muxport)
70{
71 struct parport *extra = parport_register_port(real->base,
72 real->irq,
73 real->dma,
74 real->ops);
75 if (extra) {
76 extra->portnum = real->portnum;
77 extra->physport = real;
78 extra->muxport = muxport;
79 real->slaves[muxport-1] = extra;
80 }
81
82 return extra;
83}
84
85static int daisy_drv_probe(struct pardevice *par_dev)
86{
87 struct device_driver *drv = par_dev->dev.driver;
88
89 if (strcmp(drv->name, "daisy_drv"))
90 return -ENODEV;
91 if (strcmp(par_dev->name, daisy_dev_name))
92 return -ENODEV;
93
94 return 0;
95}
96
97static struct parport_driver daisy_driver = {
98 .name = "daisy_drv",
99 .probe = daisy_drv_probe,
100};
101
102/* Discover the IEEE1284.3 topology on a port -- muxes and daisy chains.
103 * Return value is number of devices actually detected. */
104int parport_daisy_init(struct parport *port)
105{
106 int detected = 0;
107 char *deviceid;
108 static const char *th[] = { /*0*/"th", "st", "nd", "rd", "th" };
109 int num_ports;
110 int i;
111 int last_try = 0;
112
113 if (!daisy_init_done) {
114 /*
115 * flag should be marked true first as
116 * parport_register_driver() might try to load the low
117 * level driver which will lead to announcing new ports
118 * and which will again come back here at
119 * parport_daisy_init()
120 */
121 daisy_init_done = true;
122 i = parport_register_driver(&daisy_driver);
123 if (i) {
124 pr_err("daisy registration failed\n");
125 daisy_init_done = false;
126 return i;
127 }
128 }
129
130again:
131 /* Because this is called before any other devices exist,
132 * we don't have to claim exclusive access. */
133
134 /* If mux present on normal port, need to create new
135 * parports for each extra port. */
136 if (port->muxport < 0 && mux_present(port) &&
137 /* don't be fooled: a mux must have 2 or 4 ports. */
138 ((num_ports = num_mux_ports(port)) == 2 || num_ports == 4)) {
139 /* Leave original as port zero. */
140 port->muxport = 0;
141 pr_info("%s: 1st (default) port of %d-way multiplexor\n",
142 port->name, num_ports);
143 for (i = 1; i < num_ports; i++) {
144 /* Clone the port. */
145 struct parport *extra = clone_parport(port, i);
146 if (!extra) {
147 if (signal_pending(current))
148 break;
149
150 schedule();
151 continue;
152 }
153
154 pr_info("%s: %d%s port of %d-way multiplexor on %s\n",
155 extra->name, i + 1, th[i + 1], num_ports,
156 port->name);
157
158 /* Analyse that port too. We won't recurse
159 forever because of the 'port->muxport < 0'
160 test above. */
161 parport_daisy_init(extra);
162 }
163 }
164
165 if (port->muxport >= 0)
166 select_port(port);
167
168 parport_daisy_deselect_all(port);
169 detected += assign_addrs(port);
170
171 /* Count the potential legacy device at the end. */
172 add_dev(numdevs++, port, -1);
173
174 /* Find out the legacy device's IEEE 1284 device ID. */
175 deviceid = kmalloc(1024, GFP_KERNEL);
176 if (deviceid) {
177 if (parport_device_id(numdevs - 1, deviceid, 1024) > 2)
178 detected++;
179
180 kfree(deviceid);
181 }
182
183 if (!detected && !last_try) {
184 /* No devices were detected. Perhaps they are in some
185 funny state; let's try to reset them and see if
186 they wake up. */
187 parport_daisy_fini(port);
188 parport_write_control(port, PARPORT_CONTROL_SELECT);
189 udelay(50);
190 parport_write_control(port,
191 PARPORT_CONTROL_SELECT |
192 PARPORT_CONTROL_INIT);
193 udelay(50);
194 last_try = 1;
195 goto again;
196 }
197
198 return detected;
199}
200
201/* Forget about devices on a physical port. */
202void parport_daisy_fini(struct parport *port)
203{
204 struct daisydev **p;
205
206 spin_lock(&topology_lock);
207 p = &topology;
208 while (*p) {
209 struct daisydev *dev = *p;
210 if (dev->port != port) {
211 p = &dev->next;
212 continue;
213 }
214 *p = dev->next;
215 kfree(dev);
216 }
217
218 /* Gaps in the numbering could be handled better. How should
219 someone enumerate through all IEEE1284.3 devices in the
220 topology?. */
221 if (!topology) numdevs = 0;
222 spin_unlock(&topology_lock);
223 return;
224}
225
226/**
227 * parport_open - find a device by canonical device number
228 * @devnum: canonical device number
229 * @name: name to associate with the device
230 *
231 * This function is similar to parport_register_device(), except
232 * that it locates a device by its number rather than by the port
233 * it is attached to.
234 *
235 * All parameters except for @devnum are the same as for
236 * parport_register_device(). The return value is the same as
237 * for parport_register_device().
238 **/
239
240struct pardevice *parport_open(int devnum, const char *name)
241{
242 struct daisydev *p = topology;
243 struct pardev_cb par_cb;
244 struct parport *port;
245 struct pardevice *dev;
246 int daisy;
247
248 memset(&par_cb, 0, sizeof(par_cb));
249 spin_lock(&topology_lock);
250 while (p && p->devnum != devnum)
251 p = p->next;
252
253 if (!p) {
254 spin_unlock(&topology_lock);
255 return NULL;
256 }
257
258 daisy = p->daisy;
259 port = parport_get_port(p->port);
260 spin_unlock(&topology_lock);
261
262 dev = parport_register_dev_model(port, name, &par_cb, devnum);
263 parport_put_port(port);
264 if (!dev)
265 return NULL;
266
267 dev->daisy = daisy;
268
269 /* Check that there really is a device to select. */
270 if (daisy >= 0) {
271 int selected;
272 parport_claim_or_block(dev);
273 selected = port->daisy;
274 parport_release(dev);
275
276 if (selected != daisy) {
277 /* No corresponding device. */
278 parport_unregister_device(dev);
279 return NULL;
280 }
281 }
282
283 return dev;
284}
285
286/**
287 * parport_close - close a device opened with parport_open()
288 * @dev: device to close
289 *
290 * This is to parport_open() as parport_unregister_device() is to
291 * parport_register_device().
292 **/
293
294void parport_close(struct pardevice *dev)
295{
296 parport_unregister_device(dev);
297}
298
299/* Send a daisy-chain-style CPP command packet. */
300static int cpp_daisy(struct parport *port, int cmd)
301{
302 unsigned char s;
303
304 parport_data_forward(port);
305 parport_write_data(port, 0xaa); udelay(2);
306 parport_write_data(port, 0x55); udelay(2);
307 parport_write_data(port, 0x00); udelay(2);
308 parport_write_data(port, 0xff); udelay(2);
309 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
310 | PARPORT_STATUS_PAPEROUT
311 | PARPORT_STATUS_SELECT
312 | PARPORT_STATUS_ERROR);
313 if (s != (PARPORT_STATUS_BUSY
314 | PARPORT_STATUS_PAPEROUT
315 | PARPORT_STATUS_SELECT
316 | PARPORT_STATUS_ERROR)) {
317 pr_debug("%s: cpp_daisy: aa5500ff(%02x)\n", port->name, s);
318 return -ENXIO;
319 }
320
321 parport_write_data(port, 0x87); udelay(2);
322 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
323 | PARPORT_STATUS_PAPEROUT
324 | PARPORT_STATUS_SELECT
325 | PARPORT_STATUS_ERROR);
326 if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
327 pr_debug("%s: cpp_daisy: aa5500ff87(%02x)\n", port->name, s);
328 return -ENXIO;
329 }
330
331 parport_write_data(port, 0x78); udelay(2);
332 parport_write_data(port, cmd); udelay(2);
333 parport_frob_control(port,
334 PARPORT_CONTROL_STROBE,
335 PARPORT_CONTROL_STROBE);
336 udelay(1);
337 s = parport_read_status(port);
338 parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
339 udelay(1);
340 parport_write_data(port, 0xff); udelay(2);
341
342 return s;
343}
344
345/* Send a mux-style CPP command packet. */
346static int cpp_mux(struct parport *port, int cmd)
347{
348 unsigned char s;
349 int rc;
350
351 parport_data_forward(port);
352 parport_write_data(port, 0xaa); udelay(2);
353 parport_write_data(port, 0x55); udelay(2);
354 parport_write_data(port, 0xf0); udelay(2);
355 parport_write_data(port, 0x0f); udelay(2);
356 parport_write_data(port, 0x52); udelay(2);
357 parport_write_data(port, 0xad); udelay(2);
358 parport_write_data(port, cmd); udelay(2);
359
360 s = parport_read_status(port);
361 if (!(s & PARPORT_STATUS_ACK)) {
362 pr_debug("%s: cpp_mux: aa55f00f52ad%02x(%02x)\n",
363 port->name, cmd, s);
364 return -EIO;
365 }
366
367 rc = (((s & PARPORT_STATUS_SELECT ? 1 : 0) << 0) |
368 ((s & PARPORT_STATUS_PAPEROUT ? 1 : 0) << 1) |
369 ((s & PARPORT_STATUS_BUSY ? 0 : 1) << 2) |
370 ((s & PARPORT_STATUS_ERROR ? 0 : 1) << 3));
371
372 return rc;
373}
374
375void parport_daisy_deselect_all(struct parport *port)
376{
377 cpp_daisy(port, 0x30);
378}
379
380int parport_daisy_select(struct parport *port, int daisy, int mode)
381{
382 switch (mode)
383 {
384 // For these modes we should switch to EPP mode:
385 case IEEE1284_MODE_EPP:
386 case IEEE1284_MODE_EPPSL:
387 case IEEE1284_MODE_EPPSWE:
388 return !(cpp_daisy(port, 0x20 + daisy) &
389 PARPORT_STATUS_ERROR);
390
391 // For these modes we should switch to ECP mode:
392 case IEEE1284_MODE_ECP:
393 case IEEE1284_MODE_ECPRLE:
394 case IEEE1284_MODE_ECPSWE:
395 return !(cpp_daisy(port, 0xd0 + daisy) &
396 PARPORT_STATUS_ERROR);
397
398 // Nothing was told for BECP in Daisy chain specification.
399 // May be it's wise to use ECP?
400 case IEEE1284_MODE_BECP:
401 // Others use compat mode
402 case IEEE1284_MODE_NIBBLE:
403 case IEEE1284_MODE_BYTE:
404 case IEEE1284_MODE_COMPAT:
405 default:
406 return !(cpp_daisy(port, 0xe0 + daisy) &
407 PARPORT_STATUS_ERROR);
408 }
409}
410
411static int mux_present(struct parport *port)
412{
413 return cpp_mux(port, 0x51) == 3;
414}
415
416static int num_mux_ports(struct parport *port)
417{
418 return cpp_mux(port, 0x58);
419}
420
421static int select_port(struct parport *port)
422{
423 int muxport = port->muxport;
424 return cpp_mux(port, 0x60 + muxport) == muxport;
425}
426
427static int assign_addrs(struct parport *port)
428{
429 unsigned char s;
430 unsigned char daisy;
431 int thisdev = numdevs;
432 int detected;
433 char *deviceid;
434
435 parport_data_forward(port);
436 parport_write_data(port, 0xaa); udelay(2);
437 parport_write_data(port, 0x55); udelay(2);
438 parport_write_data(port, 0x00); udelay(2);
439 parport_write_data(port, 0xff); udelay(2);
440 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
441 | PARPORT_STATUS_PAPEROUT
442 | PARPORT_STATUS_SELECT
443 | PARPORT_STATUS_ERROR);
444 if (s != (PARPORT_STATUS_BUSY
445 | PARPORT_STATUS_PAPEROUT
446 | PARPORT_STATUS_SELECT
447 | PARPORT_STATUS_ERROR)) {
448 pr_debug("%s: assign_addrs: aa5500ff(%02x)\n", port->name, s);
449 return 0;
450 }
451
452 parport_write_data(port, 0x87); udelay(2);
453 s = parport_read_status(port) & (PARPORT_STATUS_BUSY
454 | PARPORT_STATUS_PAPEROUT
455 | PARPORT_STATUS_SELECT
456 | PARPORT_STATUS_ERROR);
457 if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
458 pr_debug("%s: assign_addrs: aa5500ff87(%02x)\n", port->name, s);
459 return 0;
460 }
461
462 parport_write_data(port, 0x78); udelay(2);
463 s = parport_read_status(port);
464
465 for (daisy = 0;
466 (s & (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT))
467 == (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT)
468 && daisy < 4;
469 ++daisy) {
470 parport_write_data(port, daisy);
471 udelay(2);
472 parport_frob_control(port,
473 PARPORT_CONTROL_STROBE,
474 PARPORT_CONTROL_STROBE);
475 udelay(1);
476 parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
477 udelay(1);
478
479 add_dev(numdevs++, port, daisy);
480
481 /* See if this device thought it was the last in the
482 * chain. */
483 if (!(s & PARPORT_STATUS_BUSY))
484 break;
485
486 /* We are seeing pass through status now. We see
487 last_dev from next device or if last_dev does not
488 work status lines from some non-daisy chain
489 device. */
490 s = parport_read_status(port);
491 }
492
493 parport_write_data(port, 0xff); udelay(2);
494 detected = numdevs - thisdev;
495 pr_debug("%s: Found %d daisy-chained devices\n", port->name, detected);
496
497 /* Ask the new devices to introduce themselves. */
498 deviceid = kmalloc(1024, GFP_KERNEL);
499 if (!deviceid) return 0;
500
501 for (daisy = 0; thisdev < numdevs; thisdev++, daisy++)
502 parport_device_id(thisdev, deviceid, 1024);
503
504 kfree(deviceid);
505 return detected;
506}