ss_mustek.c revision 1.12.4.4 1 /* $NetBSD: ss_mustek.c,v 1.12.4.4 2002/01/08 00:31:56 nathanw Exp $ */
2
3 /*
4 * Copyright (c) 1995 Joachim Koenig-Baltes. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 * must display the following acknowledgement:
16 * This product includes software developed by Joachim Koenig-Baltes.
17 * 4. The name of the author may not be used to endorse or promote products
18 * derived from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 /*
33 * special driver for MUSTEK flatbed scanners MFS 06000CX and MFS 12000CX
34 * these scanners come with their own scsi card, containing an NCR53C400
35 * SCSI controller chip. I'm in the progress of writing a driver for this
36 * card to work under NetBSD-current. I've hooked it up to a Seagate ST01
37 * hostadapter in the meantime, giving 350KB/sec for higher resolutions!
38 *
39 * I tried to connect it to my Adaptec 1542B, but with no success. It seems,
40 * it does not like synchronous negotiation between Hostadapter and other
41 * targets, but I could not turn this off for the 1542B.
42 *
43 * There is also an other reason why you would not like to connect it to your
44 * favourite SCSI host adapter: The Mustek DOES NOT DISCONNECT. It will block
45 * other traffic from the bus while a transfer is active.
46 */
47
48 #include <sys/cdefs.h>
49 __KERNEL_RCSID(0, "$NetBSD: ss_mustek.c,v 1.12.4.4 2002/01/08 00:31:56 nathanw Exp $");
50
51 #include <sys/param.h>
52 #include <sys/kernel.h>
53 #include <sys/systm.h>
54 #include <sys/fcntl.h>
55 #include <sys/errno.h>
56 #include <sys/ioctl.h>
57 #include <sys/malloc.h>
58 #include <sys/buf.h>
59 #include <sys/proc.h>
60 #include <sys/user.h>
61 #include <sys/device.h>
62 #include <sys/conf.h> /* for cdevsw */
63 #include <sys/scanio.h>
64
65 #include <dev/scsipi/scsi_all.h>
66 #include <dev/scsipi/scsipi_all.h>
67 #include <dev/scsipi/scsi_scanner.h>
68 #include <dev/scsipi/scsiconf.h>
69 #include <dev/scsipi/ssvar.h>
70 #include <dev/scsipi/ss_mustek.h>
71
72 #define MUSTEK_RETRIES 4
73
74 int mustek_get_params __P((struct ss_softc *));
75 int mustek_set_params __P((struct ss_softc *, struct scan_io *));
76 int mustek_trigger_scanner __P((struct ss_softc *));
77 void mustek_minphys __P((struct ss_softc *, struct buf *));
78 int mustek_read __P((struct ss_softc *, struct buf *));
79 int mustek_rewind_scanner __P((struct ss_softc *));
80
81 /* only used internally */
82 int mustek_get_status __P((struct ss_softc *, int, int));
83 void mustek_compute_sizes __P((struct ss_softc *));
84
85 /*
86 * structure for the special handlers
87 */
88 struct ss_special mustek_special = {
89 mustek_set_params,
90 mustek_trigger_scanner,
91 mustek_get_params,
92 mustek_minphys,
93 mustek_read,
94 mustek_rewind_scanner,
95 NULL, /* no adf support right now */
96 NULL /* no adf support right now */
97 };
98
99 /*
100 * mustek_attach: attach special functions to ss
101 */
102 void
103 mustek_attach(ss, sa)
104 struct ss_softc *ss;
105 struct scsipibus_attach_args *sa;
106 {
107 #ifdef SCSIPI_DEBUG
108 struct scsipi_periph *periph = sa->sa_periph;
109 #endif
110
111 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_attach: start\n"));
112 ss->sio.scan_scanner_type = 0;
113
114 printf("\n%s: ", ss->sc_dev.dv_xname);
115
116 /* first, check the model which determines resolutions */
117 if (!memcmp(sa->sa_inqbuf.product, "MFS-06000CX", 11)) {
118 ss->sio.scan_scanner_type = MUSTEK_06000CX;
119 printf("Mustek 6000CX Flatbed 3-pass color scanner, 3 - 600 dpi\n");
120 }
121 if (!memcmp(sa->sa_inqbuf.product, "MFS-12000CX", 11)) {
122 ss->sio.scan_scanner_type = MUSTEK_12000CX;
123 printf("Mustek 12000CX Flatbed 3-pass color scanner, 6 - 1200 dpi\n");
124 }
125
126 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_attach: scanner_type = %d\n",
127 ss->sio.scan_scanner_type));
128
129 /* install special handlers */
130 ss->special = &mustek_special;
131
132 /*
133 * populate the scanio struct with legal values
134 * the default should come from user space
135 */
136 ss->sio.scan_width = 1200;
137 ss->sio.scan_height = 1200;
138 ss->sio.scan_x_resolution = 99;
139 ss->sio.scan_y_resolution = 99;
140 ss->sio.scan_x_origin = 0;
141 ss->sio.scan_y_origin = 0;
142 ss->sio.scan_brightness = 100;
143 ss->sio.scan_contrast = 100;
144 ss->sio.scan_quality = 100;
145 ss->sio.scan_image_mode = SIM_GRAYSCALE;
146
147 mustek_compute_sizes(ss);
148 }
149
150 int
151 mustek_get_params (ss)
152 struct ss_softc *ss;
153 {
154
155 return (0);
156 }
157
158 /*
159 * check the parameters if the mustek is capable of fulfilling it
160 * but don't send the command to the scanner in case the user wants
161 * to change parameters by more than one call
162 */
163 int
164 mustek_set_params(ss, sio)
165 struct ss_softc *ss;
166 struct scan_io *sio;
167 {
168 int error;
169
170 /*
171 * if the scanner is triggered, then rewind it
172 */
173 if (ss->flags & SSF_TRIGGERED) {
174 error = mustek_rewind_scanner(ss);
175 if (error)
176 return (error);
177 }
178
179 /* size constraints: 8.5" horizontally and 14" vertically */
180 #ifdef MUSTEK_INCH_SPEC
181 /* sizes must be a multiple of 1/8" */
182 sio->scan_x_origin -= sio->scan_x_origin % 150;
183 sio->scan_y_origin -= sio->scan_y_origin % 150;
184 sio->scan_width -= sio->scan_width % 150;
185 sio->scan_height -= sio->scan_height % 150;
186 #endif
187 if (sio->scan_width == 0 ||
188 sio->scan_x_origin + sio->scan_width > 10200 ||
189 sio->scan_height == 0 ||
190 sio->scan_y_origin + sio->scan_height > 16800)
191 return (EINVAL);
192
193 /*
194 * for now, only realize the values for the MUSTEK_06000CX
195 * in the future, values for the MUSTEK_12000CX will be implemented
196 */
197
198 /*
199 * resolution (dpi) must be <= 300 and a multiple of 3 or
200 * between 300 and 600 and a multiple of 30
201 */
202 sio->scan_x_resolution -= sio->scan_x_resolution <= 300 ?
203 sio->scan_x_resolution % 3 : sio->scan_x_resolution % 30;
204 sio->scan_y_resolution -= sio->scan_y_resolution <= 300 ?
205 sio->scan_y_resolution % 3 : sio->scan_y_resolution % 30;
206 if (sio->scan_x_resolution < 3 || sio->scan_x_resolution > 600 ||
207 sio->scan_x_resolution != sio->scan_y_resolution)
208 return (EINVAL);
209
210 /* assume brightness values are between 64 and 136 in steps of 3 */
211 sio->scan_brightness -= (sio->scan_brightness - 64) % 3;
212 if (sio->scan_brightness < 64 || sio->scan_brightness > 136)
213 return (EINVAL);
214
215 /* contrast values must be between 16 and 184 in steps of 7 */
216 sio->scan_contrast -= (sio->scan_contrast - 16) % 7;
217 if (sio->scan_contrast < 16 || sio->scan_contrast > 184)
218 return (EINVAL);
219
220 /*
221 * velocity: between 0 (fast) and 4 (slow) which will be mapped
222 * to 100% = 4, 80% = 3, 60% = 2, 40% = 1, 20% = 0
223 * must be a multiple of 20
224 */
225 sio->scan_quality -= sio->scan_quality % 20;
226 if (sio->scan_quality < 20 || sio->scan_quality > 100)
227 return (EINVAL);
228
229 switch (sio->scan_image_mode) {
230 case SIM_BINARY_MONOCHROME:
231 case SIM_DITHERED_MONOCHROME:
232 case SIM_GRAYSCALE:
233 case SIM_RED:
234 case SIM_GREEN:
235 case SIM_BLUE:
236 break;
237 default:
238 return (EINVAL);
239 }
240
241 /* change ss_softc to the new values, but save ro-variables */
242 sio->scan_scanner_type = ss->sio.scan_scanner_type;
243 memcpy(&ss->sio, sio, sizeof(struct scan_io));
244
245 mustek_compute_sizes(ss);
246
247 return (0);
248 }
249
250 /*
251 * trim the requested transfer to a multiple of the line size
252 * this is called only from ssread() which guarantees, scanner is triggered
253 * In the future, it will trim the transfer to not read to much at a time
254 * because the mustek cannot disconnect. It will be calculated by the
255 * resolution, the velocity and the number of bytes per line.
256 */
257 void
258 mustek_minphys(ss, bp)
259 struct ss_softc *ss;
260 struct buf *bp;
261 {
262 #ifdef SCSIPI_DEBUG
263 struct scsipi_periph *periph = ss->sc_periph;
264 #endif
265
266 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_minphys: before: %ld\n",
267 bp->b_bcount));
268 bp->b_bcount -= bp->b_bcount %
269 ((ss->sio.scan_pixels_per_line * ss->sio.scan_bits_per_pixel) / 8);
270 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_minphys: after: %ld\n",
271 bp->b_bcount));
272 }
273
274 /*
275 * trigger the scanner to start a scan operation
276 * this includes sending the mode- and window-data, starting the scanner
277 * and getting the image size info
278 */
279 int
280 mustek_trigger_scanner(ss)
281 struct ss_softc *ss;
282 {
283 struct mustek_mode_select_cmd mode_cmd;
284 struct mustek_mode_select_data mode_data;
285 struct mustek_set_window_cmd window_cmd;
286 struct mustek_set_window_data window_data;
287 struct mustek_start_scan_cmd start_scan_cmd;
288 struct scsipi_periph *periph = ss->sc_periph;
289 int pixel_tlx, pixel_tly, pixel_brx, pixel_bry, paperlength;
290 int error;
291
292 mustek_compute_sizes(ss);
293
294 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner\n"));
295
296 /*
297 * set the window params and send the scsi command
298 */
299 memset(&window_cmd, 0, sizeof(window_cmd));
300 window_cmd.opcode = MUSTEK_SET_WINDOW;
301 window_cmd.length = sizeof(window_data);
302
303 memset(&window_data, 0, sizeof(window_data));
304 window_data.frame.header = MUSTEK_LINEART_BACKGROUND | MUSTEK_UNIT_SPEC;
305 #ifdef MUSTEK_INCH_SPEC
306 /* the positional values are all 1 byte because 256 / 8 = 32" */
307 pixel_tlx = ss->sio.scan_x_origin / 150;
308 pixel_tly = ss->sio.scan_y_origin / 150;
309 pixel_brx = pixel_tlx + ss->sio.scan_width / 150;
310 pixel_bry = pixel_tly + ss->sio.scan_height / 150;
311 #else
312 pixel_tlx = (ss->sio.scan_x_origin * ss->sio.scan_x_resolution) / 1200;
313 pixel_tly = (ss->sio.scan_y_origin * ss->sio.scan_y_resolution) / 1200;
314 pixel_brx = pixel_tlx +
315 (ss->sio.scan_width * ss->sio.scan_x_resolution) / 1200;
316 pixel_bry = pixel_tly +
317 (ss->sio.scan_height * ss->sio.scan_y_resolution) / 1200;
318 #endif
319 _lto2l(pixel_tlx, window_data.frame.tl_x);
320 _lto2l(pixel_tly, window_data.frame.tl_y);
321 _lto2l(pixel_brx, window_data.frame.br_x);
322 _lto2l(pixel_bry, window_data.frame.br_y);
323
324 #if MUSTEK_WINDOWS >= 1
325 window_data.window1 = window_data.frame;
326 window_data.window1.header = MUSTEK_WINDOW_MASK | MUSTEK_UNIT_SPEC;
327 #endif
328
329 /* send the set window command to the scanner */
330 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_set_parms: set_window\n"));
331 error = scsipi_command(periph,
332 (struct scsipi_generic *) &window_cmd,
333 sizeof(window_cmd), (u_char *) &window_data, sizeof(window_data),
334 MUSTEK_RETRIES, 5000, NULL, XS_CTL_DATA_OUT | XS_CTL_DATA_ONSTACK);
335 if (error)
336 return (error);
337
338 /*
339 * do what it takes to actualize the mode
340 */
341 memset(&mode_cmd, 0, sizeof(mode_cmd));
342 mode_cmd.opcode = MUSTEK_MODE_SELECT;
343 _lto2b(sizeof(mode_data), mode_cmd.length);
344
345 memset(&mode_data, 0, sizeof(mode_data));
346 mode_data.mode =
347 MUSTEK_MODE_MASK | MUSTEK_HT_PATTERN_BUILTIN | MUSTEK_UNIT_SPEC;
348 if (ss->sio.scan_x_resolution <= 300) {
349 mode_data.resolution = ss->sio.scan_x_resolution / 3;
350 } else {
351 /*
352 * the resolution values is computed by modulo 100, but not
353 * for 600dpi, where the value is 100 (a bit tricky, but ...)
354 */
355 mode_data.resolution =
356 ((ss->sio.scan_x_resolution - 1) % 100) + 1;
357 }
358 mode_data.brightness = (ss->sio.scan_brightness - 64) / 3;
359 mode_data.contrast = (ss->sio.scan_contrast - 16) / 7;
360 mode_data.grain = 0;
361 mode_data.velocity = ss->sio.scan_quality / 20 - 1;
362 #ifdef MUSTEK_INCH_SPEC
363 paperlength = 14 * 8; /* 14" */
364 #else
365 paperlength = 14 * ss->sio.scan_y_resolution; /* 14" */
366 #endif
367 _lto2l(paperlength, mode_data.paperlength);
368
369 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner: mode_select\n"));
370 /* send the command to the scanner */
371 error = scsipi_command(periph,
372 (struct scsipi_generic *) &mode_cmd,
373 sizeof(mode_cmd), (u_char *) &mode_data, sizeof(mode_data),
374 MUSTEK_RETRIES, 5000, NULL, XS_CTL_DATA_OUT | XS_CTL_DATA_ONSTACK);
375 if (error)
376 return (error);
377
378 /*
379 * now construct and send the start command
380 */
381 memset(&start_scan_cmd, 0, sizeof(start_scan_cmd));
382 start_scan_cmd.opcode = MUSTEK_START_STOP;
383 start_scan_cmd.mode = MUSTEK_SCAN_START;
384 if (ss->sio.scan_x_resolution <= 300)
385 start_scan_cmd.mode |= MUSTEK_RES_STEP_1;
386 else
387 start_scan_cmd.mode |= MUSTEK_RES_STEP_10;
388 switch (ss->sio.scan_image_mode) {
389 case SIM_BINARY_MONOCHROME:
390 case SIM_DITHERED_MONOCHROME:
391 start_scan_cmd.mode |= MUSTEK_BIT_MODE | MUSTEK_GRAY_FILTER;
392 break;
393 case SIM_GRAYSCALE:
394 start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_GRAY_FILTER;
395 break;
396 case SIM_RED:
397 start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_RED_FILTER;
398 break;
399 case SIM_GREEN:
400 start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_GREEN_FILTER;
401 break;
402 case SIM_BLUE:
403 start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_BLUE_FILTER;
404 break;
405 }
406
407 /* send the command to the scanner */
408 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner: start_scan\n"));
409 error = scsipi_command(periph,
410 (struct scsipi_generic *) &start_scan_cmd,
411 sizeof(start_scan_cmd), NULL, 0,
412 MUSTEK_RETRIES, 5000, NULL, 0);
413 if (error)
414 return (error);
415
416 /*
417 * now check if scanner ready this time with update of size info
418 * we wait here so that if the user issues a read directly afterwards,
419 * the scanner will respond directly (otherwise we had to sleep with
420 * a buffer locked in memory)
421 */
422 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner: get_status\n"));
423 error = mustek_get_status(ss, 60, 1);
424 if (error)
425 return (error);
426
427 return (0);
428 }
429
430 /*
431 * stop a scan operation in progress
432 */
433 int
434 mustek_rewind_scanner(ss)
435 struct ss_softc *ss;
436 {
437 struct mustek_start_scan_cmd cmd;
438 struct scsipi_periph *periph = ss->sc_periph;
439 int error;
440
441 if (ss->sio.scan_window_size != 0) {
442 /*
443 * only if not all data has been read, the scanner has to be
444 * stopped
445 */
446 memset(&cmd, 0, sizeof(cmd));
447 cmd.opcode = MUSTEK_START_STOP;
448 cmd.mode = MUSTEK_SCAN_STOP;
449
450 /* send the command to the scanner */
451 SC_DEBUG(periph, SCSIPI_DB1,
452 ("mustek_rewind_scanner: stop_scan\n"));
453 error = scsipi_command(periph,
454 (struct scsipi_generic *) &cmd,
455 sizeof(cmd), NULL, 0, MUSTEK_RETRIES, 5000, NULL, 0);
456 if (error)
457 return (error);
458 }
459
460 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_rewind_scanner: end\n"));
461
462 return (0);
463 }
464
465 /*
466 * read the requested number of bytes/lines from the scanner
467 */
468 int
469 mustek_read(ss, bp)
470 struct ss_softc *ss;
471 struct buf *bp;
472 {
473 struct mustek_read_cmd cmd;
474 struct scsipi_periph *periph = ss->sc_periph;
475 u_long lines_to_read;
476 int error;
477
478 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_read: start\n"));
479
480 memset(&cmd, 0, sizeof(cmd));
481 cmd.opcode = MUSTEK_READ;
482
483 /* instead of the bytes, the mustek wants the number of lines */
484 lines_to_read = bp->b_bcount /
485 ((ss->sio.scan_pixels_per_line * ss->sio.scan_bits_per_pixel) / 8);
486 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_read: read %ld lines\n",
487 lines_to_read));
488 _lto3b(lines_to_read, cmd.length);
489
490 /*
491 * go ask the adapter to do all this for us
492 */
493 error = scsipi_command(periph,
494 (struct scsipi_generic *) &cmd, sizeof(cmd),
495 (u_char *) bp->b_data, bp->b_bcount, MUSTEK_RETRIES, 10000, bp,
496 XS_CTL_NOSLEEP | XS_CTL_ASYNC | XS_CTL_DATA_IN);
497 if (error) {
498 printf("%s: not queued, error %d\n", ss->sc_dev.dv_xname,
499 error);
500 } else {
501 ss->sio.scan_lines -= lines_to_read;
502 if (ss->sio.scan_lines < 0)
503 ss->sio.scan_lines = 0;
504 ss->sio.scan_window_size -= bp->b_bcount;
505 if (ss->sio.scan_window_size < 0)
506 ss->sio.scan_window_size = 0;
507 }
508
509 return (0);
510 }
511
512 /*
513 * check if the scanner is ready to take commands
514 * wait timeout seconds and try only every second
515 * if update, then update picture size info
516 *
517 * returns EBUSY if scanner not ready
518 */
519 int
520 mustek_get_status(ss, timeout, update)
521 struct ss_softc *ss;
522 int timeout, update;
523 {
524 struct mustek_get_status_cmd cmd;
525 struct mustek_get_status_data data;
526 struct scsipi_periph *periph = ss->sc_periph;
527 int error, lines, bytes_per_line;
528
529 memset(&cmd, 0, sizeof(cmd));
530 cmd.opcode = MUSTEK_GET_STATUS;
531 cmd.length = sizeof(data);
532
533 while (1) {
534 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_get_status: stat_cmd\n"));
535 error = scsipi_command(periph,
536 (struct scsipi_generic *) &cmd, sizeof(cmd),
537 (u_char *) &data, sizeof(data), MUSTEK_RETRIES,
538 5000, NULL, XS_CTL_DATA_IN | XS_CTL_DATA_ONSTACK);
539 if (error)
540 return (error);
541 if ((data.ready_busy == MUSTEK_READY) ||
542 (timeout-- <= 0))
543 break;
544 /* please wait a second */
545 tsleep((caddr_t)mustek_get_status, PRIBIO + 1, "mtkrdy", hz);
546 }
547
548 if (update) {
549 bytes_per_line = _2ltol(data.bytes_per_line);
550 lines = _3ltol(data.lines);
551 if (lines != ss->sio.scan_lines) {
552 printf("mustek: lines actual(%d) != computed(%ld)\n",
553 lines, ss->sio.scan_lines);
554 return (EIO);
555 }
556 if (bytes_per_line * lines != ss->sio.scan_window_size) {
557 printf("mustek: win-size actual(%d) != computed(%ld)\n",
558 bytes_per_line * lines, ss->sio.scan_window_size);
559 return (EIO);
560 }
561
562 SC_DEBUG(periph, SCSIPI_DB1,
563 ("mustek_get_size: bpl=%ld, lines=%ld\n",
564 (ss->sio.scan_pixels_per_line * ss->sio.scan_bits_per_pixel) / 8,
565 ss->sio.scan_lines));
566 SC_DEBUG(periph, SCSIPI_DB1, ("window size = %ld\n",
567 ss->sio.scan_window_size));
568 }
569
570 SC_DEBUG(periph, SCSIPI_DB1, ("mustek_get_status: end\n"));
571 if (data.ready_busy == MUSTEK_READY)
572 return (0);
573 else
574 return (EBUSY);
575 }
576
577 /*
578 * mustek_compute_sizes: compute window_size and lines for the picture
579 * this function is called from different places in the code
580 */
581 void
582 mustek_compute_sizes(ss)
583 struct ss_softc *ss;
584 {
585
586 switch (ss->sio.scan_image_mode) {
587 case SIM_BINARY_MONOCHROME:
588 case SIM_DITHERED_MONOCHROME:
589 ss->sio.scan_bits_per_pixel = 1;
590 break;
591 case SIM_GRAYSCALE:
592 case SIM_RED:
593 case SIM_GREEN:
594 case SIM_BLUE:
595 ss->sio.scan_bits_per_pixel = 8;
596 break;
597 }
598
599 /*
600 * horizontal number of bytes is always a multiple of 2,
601 * in 8-bit mode at least
602 */
603 ss->sio.scan_pixels_per_line =
604 (ss->sio.scan_width * ss->sio.scan_x_resolution) / 1200;
605 if (ss->sio.scan_bits_per_pixel == 1)
606 /* make it a multiple of 16, and thus of 2 bytes */
607 ss->sio.scan_pixels_per_line =
608 (ss->sio.scan_pixels_per_line + 15) & 0xfffffff0;
609 else
610 ss->sio.scan_pixels_per_line =
611 (ss->sio.scan_pixels_per_line + 1) & 0xfffffffe;
612
613 ss->sio.scan_lines =
614 (ss->sio.scan_height * ss->sio.scan_y_resolution) / 1200;
615 ss->sio.scan_window_size = ss->sio.scan_lines *
616 ((ss->sio.scan_pixels_per_line * ss->sio.scan_bits_per_pixel) / 8);
617 }
618