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ss_mustek.c revision 1.24
      1 /*	$NetBSD: ss_mustek.c,v 1.24 2004/09/18 00:08:16 mycroft 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 1.24 2004/09/18 00:08:16 mycroft 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/scsipi_base.h>
     70 #include <dev/scsipi/ssvar.h>
     71 #include <dev/scsipi/ss_mustek.h>
     72 
     73 #define MUSTEK_RETRIES 4
     74 
     75 static int	mustek_get_params(struct ss_softc *);
     76 static int	mustek_set_params(struct ss_softc *, struct scan_io *);
     77 static int	mustek_trigger_scanner(struct ss_softc *);
     78 static void	mustek_minphys(struct ss_softc *, struct buf *);
     79 static int	mustek_read(struct ss_softc *, struct buf *);
     80 static int	mustek_rewind_scanner(struct ss_softc *);
     81 
     82 /* only used internally */
     83 static int	mustek_get_status(struct ss_softc *, int, int);
     84 static void	mustek_compute_sizes(struct ss_softc *);
     85 
     86 /*
     87  * structure for the special handlers
     88  */
     89 static struct ss_special mustek_special = {
     90 	mustek_set_params,
     91 	mustek_trigger_scanner,
     92 	mustek_get_params,
     93 	mustek_minphys,
     94 	mustek_read,
     95 	mustek_rewind_scanner,
     96 	NULL,			/* no adf support right now */
     97 	NULL			/* no adf support right now */
     98 };
     99 
    100 /*
    101  * mustek_attach: attach special functions to ss
    102  */
    103 void
    104 mustek_attach(struct ss_softc *ss, struct scsipibus_attach_args *sa)
    105 {
    106 #ifdef SCSIPI_DEBUG
    107 	struct scsipi_periph *periph = sa->sa_periph;
    108 #endif
    109 
    110 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_attach: start\n"));
    111 	ss->sio.scan_scanner_type = 0;
    112 
    113 	printf("\n%s: ", ss->sc_dev.dv_xname);
    114 
    115 	/* first, check the model which determines resolutions */
    116 	if (!memcmp(sa->sa_inqbuf.product, "MFS-06000CX", 11)) {
    117 		ss->sio.scan_scanner_type = MUSTEK_06000CX;
    118 		printf("Mustek 6000CX Flatbed 3-pass color scanner, 3 - 600 dpi\n");
    119 	}
    120 	if (!memcmp(sa->sa_inqbuf.product, "MFS-12000CX", 11)) {
    121 		ss->sio.scan_scanner_type = MUSTEK_12000CX;
    122 		printf("Mustek 12000CX Flatbed 3-pass color scanner, 6 - 1200 dpi\n");
    123 	}
    124 
    125 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_attach: scanner_type = %d\n",
    126 	    ss->sio.scan_scanner_type));
    127 
    128 	/* install special handlers */
    129 	ss->special = &mustek_special;
    130 
    131 	/*
    132 	 * populate the scanio struct with legal values
    133 	 * the default should come from user space
    134 	 */
    135 	ss->sio.scan_width		= 1200;
    136 	ss->sio.scan_height		= 1200;
    137 	ss->sio.scan_x_resolution	= 99;
    138 	ss->sio.scan_y_resolution	= 99;
    139 	ss->sio.scan_x_origin		= 0;
    140 	ss->sio.scan_y_origin		= 0;
    141 	ss->sio.scan_brightness		= 100;
    142 	ss->sio.scan_contrast		= 100;
    143 	ss->sio.scan_quality		= 100;
    144 	ss->sio.scan_image_mode		= SIM_GRAYSCALE;
    145 
    146 	mustek_compute_sizes(ss);
    147 }
    148 
    149 static int
    150 mustek_get_params (struct ss_softc *ss)
    151 {
    152 
    153 	return (0);
    154 }
    155 
    156 /*
    157  * check the parameters if the mustek is capable of fulfilling it
    158  * but don't send the command to the scanner in case the user wants
    159  * to change parameters by more than one call
    160  */
    161 static int
    162 mustek_set_params(struct ss_softc *ss, struct scan_io *sio)
    163 {
    164 	int error;
    165 
    166 	/*
    167 	 * if the scanner is triggered, then rewind it
    168 	 */
    169 	if (ss->flags & SSF_TRIGGERED) {
    170 		error = mustek_rewind_scanner(ss);
    171 		if (error)
    172 			return (error);
    173 	}
    174 
    175 	/* size constraints: 8.5" horizontally and 14" vertically */
    176 #ifdef MUSTEK_INCH_SPEC
    177 	/* sizes must be a multiple of 1/8" */
    178 	sio->scan_x_origin -= sio->scan_x_origin % 150;
    179 	sio->scan_y_origin -= sio->scan_y_origin % 150;
    180 	sio->scan_width -= sio->scan_width % 150;
    181 	sio->scan_height -= sio->scan_height % 150;
    182 #endif
    183 	if (sio->scan_width == 0 ||
    184 	    sio->scan_x_origin + sio->scan_width > 10200 ||
    185 	    sio->scan_height == 0 ||
    186 	    sio->scan_y_origin + sio->scan_height > 16800)
    187 		return (EINVAL);
    188 
    189 	/*
    190 	 * for now, only realize the values for the MUSTEK_06000CX
    191 	 * in the future, values for the MUSTEK_12000CX will be implemented
    192 	 */
    193 
    194 	/*
    195 	 * resolution (dpi) must be <= 300 and a multiple of 3 or
    196 	 * between 300 and 600 and a multiple of 30
    197 	 */
    198 	sio->scan_x_resolution -= sio->scan_x_resolution <= 300 ?
    199 	    sio->scan_x_resolution % 3 : sio->scan_x_resolution % 30;
    200 	sio->scan_y_resolution -= sio->scan_y_resolution <= 300 ?
    201 	    sio->scan_y_resolution % 3 : sio->scan_y_resolution % 30;
    202 	if (sio->scan_x_resolution < 3 || sio->scan_x_resolution > 600 ||
    203 	    sio->scan_x_resolution != sio->scan_y_resolution)
    204 		return (EINVAL);
    205 
    206 	/* assume brightness values are between 64 and 136 in steps of 3 */
    207 	sio->scan_brightness -= (sio->scan_brightness - 64) % 3;
    208 	if (sio->scan_brightness < 64 || sio->scan_brightness > 136)
    209 		return (EINVAL);
    210 
    211 	/* contrast values must be between 16 and 184 in steps of 7 */
    212 	sio->scan_contrast -= (sio->scan_contrast - 16) % 7;
    213 	if (sio->scan_contrast < 16 || sio->scan_contrast > 184)
    214 		return (EINVAL);
    215 
    216 	/*
    217 	 * velocity: between 0 (fast) and 4 (slow) which will be mapped
    218 	 * to 100% = 4, 80% = 3, 60% = 2, 40% = 1, 20% = 0
    219 	 * must be a multiple of 20
    220 	 */
    221 	sio->scan_quality -= sio->scan_quality % 20;
    222 	if (sio->scan_quality < 20 || sio->scan_quality > 100)
    223 		return (EINVAL);
    224 
    225 	switch (sio->scan_image_mode) {
    226 	case SIM_BINARY_MONOCHROME:
    227 	case SIM_DITHERED_MONOCHROME:
    228 	case SIM_GRAYSCALE:
    229 	case SIM_RED:
    230 	case SIM_GREEN:
    231 	case SIM_BLUE:
    232 		break;
    233 	default:
    234 		return (EINVAL);
    235 	}
    236 
    237 	/* change ss_softc to the new values, but save ro-variables */
    238 	sio->scan_scanner_type = ss->sio.scan_scanner_type;
    239 	memcpy(&ss->sio, sio, sizeof(struct scan_io));
    240 
    241 	mustek_compute_sizes(ss);
    242 
    243 	return (0);
    244 }
    245 
    246 /*
    247  * trim the requested transfer to a multiple of the line size
    248  * this is called only from ssread() which guarantees, scanner is triggered
    249  * In the future, it will trim the transfer to not read to much at a time
    250  * because the mustek cannot disconnect. It will be calculated by the
    251  * resolution, the velocity and the number of bytes per line.
    252  */
    253 static void
    254 mustek_minphys(struct ss_softc *ss, struct buf *bp)
    255 {
    256 #ifdef SCSIPI_DEBUG
    257 	struct scsipi_periph *periph = ss->sc_periph;
    258 #endif
    259 
    260 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_minphys: before: %ld\n",
    261 	    bp->b_bcount));
    262 	bp->b_bcount -= bp->b_bcount %
    263 	    ((ss->sio.scan_pixels_per_line * ss->sio.scan_bits_per_pixel) / 8);
    264 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_minphys: after:  %ld\n",
    265 	    bp->b_bcount));
    266 }
    267 
    268 /*
    269  * trigger the scanner to start a scan operation
    270  * this includes sending the mode- and window-data, starting the scanner
    271  * and getting the image size info
    272  */
    273 static int
    274 mustek_trigger_scanner(struct ss_softc *ss)
    275 {
    276 	struct mustek_mode_select_cmd mode_cmd;
    277 	struct mustek_mode_select_data mode_data;
    278 	struct mustek_set_window_cmd window_cmd;
    279 	struct mustek_set_window_data window_data;
    280 	struct mustek_start_scan_cmd start_scan_cmd;
    281 	struct scsipi_periph *periph = ss->sc_periph;
    282 	int pixel_tlx, pixel_tly, pixel_brx, pixel_bry, paperlength;
    283 	int error;
    284 
    285 	mustek_compute_sizes(ss);
    286 
    287 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner\n"));
    288 
    289 	/*
    290 	 * set the window params and send the scsi command
    291 	 */
    292 	memset(&window_cmd, 0, sizeof(window_cmd));
    293 	window_cmd.opcode = MUSTEK_SET_WINDOW;
    294 	window_cmd.length = sizeof(window_data);
    295 
    296 	memset(&window_data, 0, sizeof(window_data));
    297 	window_data.frame.header = MUSTEK_LINEART_BACKGROUND | MUSTEK_UNIT_SPEC;
    298 #ifdef MUSTEK_INCH_SPEC
    299 	/* the positional values are all 1 byte because 256 / 8 = 32" */
    300 	pixel_tlx = ss->sio.scan_x_origin / 150;
    301 	pixel_tly = ss->sio.scan_y_origin / 150;
    302 	pixel_brx = pixel_tlx + ss->sio.scan_width / 150;
    303 	pixel_bry = pixel_tly + ss->sio.scan_height / 150;
    304 #else
    305 	pixel_tlx = (ss->sio.scan_x_origin * ss->sio.scan_x_resolution) / 1200;
    306 	pixel_tly = (ss->sio.scan_y_origin * ss->sio.scan_y_resolution) / 1200;
    307 	pixel_brx = pixel_tlx +
    308 	    (ss->sio.scan_width * ss->sio.scan_x_resolution) / 1200;
    309 	pixel_bry = pixel_tly +
    310 	    (ss->sio.scan_height * ss->sio.scan_y_resolution) / 1200;
    311 #endif
    312 	_lto2l(pixel_tlx, window_data.frame.tl_x);
    313 	_lto2l(pixel_tly, window_data.frame.tl_y);
    314 	_lto2l(pixel_brx, window_data.frame.br_x);
    315 	_lto2l(pixel_bry, window_data.frame.br_y);
    316 
    317 #if MUSTEK_WINDOWS >= 1
    318 	window_data.window1 = window_data.frame;
    319 	window_data.window1.header = MUSTEK_WINDOW_MASK | MUSTEK_UNIT_SPEC;
    320 #endif
    321 
    322 	/* send the set window command to the scanner */
    323 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_set_parms: set_window\n"));
    324 	error = scsipi_command(periph, (void *)&window_cmd, sizeof(window_cmd),
    325 	    (void *)&window_data, sizeof(window_data),
    326 	    MUSTEK_RETRIES, 5000, NULL, XS_CTL_DATA_OUT | XS_CTL_DATA_ONSTACK);
    327 	if (error)
    328 		return (error);
    329 
    330 	/*
    331 	 * do what it takes to actualize the mode
    332 	 */
    333 	memset(&mode_cmd, 0, sizeof(mode_cmd));
    334 	mode_cmd.opcode = MUSTEK_MODE_SELECT;
    335 	_lto2b(sizeof(mode_data), mode_cmd.length);
    336 
    337 	memset(&mode_data, 0, sizeof(mode_data));
    338 	mode_data.mode =
    339 	    MUSTEK_MODE_MASK | MUSTEK_HT_PATTERN_BUILTIN | MUSTEK_UNIT_SPEC;
    340 	if (ss->sio.scan_x_resolution <= 300) {
    341 		mode_data.resolution = ss->sio.scan_x_resolution / 3;
    342 	} else {
    343 		/*
    344 		 * the resolution values is computed by modulo 100, but not
    345 		 * for 600dpi, where the value is 100 (a bit tricky, but ...)
    346 		 */
    347 		mode_data.resolution =
    348 		    ((ss->sio.scan_x_resolution - 1) % 100) + 1;
    349 	}
    350 	mode_data.brightness = (ss->sio.scan_brightness - 64) / 3;
    351 	mode_data.contrast = (ss->sio.scan_contrast - 16) / 7;
    352 	mode_data.grain = 0;
    353 	mode_data.velocity = ss->sio.scan_quality / 20 - 1;
    354 #ifdef MUSTEK_INCH_SPEC
    355 	paperlength = 14 * 8;	/* 14" */
    356 #else
    357 	paperlength = 14 * ss->sio.scan_y_resolution;	/* 14" */
    358 #endif
    359 	_lto2l(paperlength, mode_data.paperlength);
    360 
    361 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner: mode_select\n"));
    362 	/* send the command to the scanner */
    363 	error = scsipi_command(periph, (void *)&mode_cmd, sizeof(mode_cmd),
    364 	    (void *)&mode_data, sizeof(mode_data),
    365 	    MUSTEK_RETRIES, 5000, NULL, XS_CTL_DATA_OUT | XS_CTL_DATA_ONSTACK);
    366 	if (error)
    367 		return (error);
    368 
    369 	/*
    370 	 * now construct and send the start command
    371 	 */
    372 	memset(&start_scan_cmd, 0, sizeof(start_scan_cmd));
    373 	start_scan_cmd.opcode = MUSTEK_START_STOP;
    374 	start_scan_cmd.mode = MUSTEK_SCAN_START;
    375 	if (ss->sio.scan_x_resolution <= 300)
    376 		start_scan_cmd.mode |= MUSTEK_RES_STEP_1;
    377 	else
    378 		start_scan_cmd.mode |= MUSTEK_RES_STEP_10;
    379 	switch (ss->sio.scan_image_mode) {
    380 	case SIM_BINARY_MONOCHROME:
    381 	case SIM_DITHERED_MONOCHROME:
    382 		start_scan_cmd.mode |= MUSTEK_BIT_MODE | MUSTEK_GRAY_FILTER;
    383 		break;
    384 	case SIM_GRAYSCALE:
    385 		start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_GRAY_FILTER;
    386 		break;
    387 	case SIM_RED:
    388 		start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_RED_FILTER;
    389 		break;
    390 	case SIM_GREEN:
    391 		start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_GREEN_FILTER;
    392 		break;
    393 	case SIM_BLUE:
    394 		start_scan_cmd.mode |= MUSTEK_GRAY_MODE | MUSTEK_BLUE_FILTER;
    395 		break;
    396 	}
    397 
    398 	/* send the command to the scanner */
    399 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner: start_scan\n"));
    400 	error = scsipi_command(periph,
    401 	    (void *)&start_scan_cmd, sizeof(start_scan_cmd),
    402 	    NULL, 0,
    403 	    MUSTEK_RETRIES, 5000, NULL, 0);
    404 	if (error)
    405 		return (error);
    406 
    407 	/*
    408 	 * now check if scanner ready this time with update of size info
    409 	 * we wait here so that if the user issues a read directly afterwards,
    410 	 * the scanner will respond directly (otherwise we had to sleep with
    411 	 * a buffer locked in memory)
    412 	 */
    413 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_trigger_scanner: get_status\n"));
    414 	error = mustek_get_status(ss, 60, 1);
    415 	if (error)
    416 		return (error);
    417 
    418 	return (0);
    419 }
    420 
    421 /*
    422  * stop a scan operation in progress
    423  */
    424 static int
    425 mustek_rewind_scanner(struct ss_softc *ss)
    426 {
    427 	struct mustek_start_scan_cmd cmd;
    428 	struct scsipi_periph *periph = ss->sc_periph;
    429 	int error;
    430 
    431 	if (ss->sio.scan_window_size != 0) {
    432 		/*
    433 		 * only if not all data has been read, the scanner has to be
    434 		 * stopped
    435 		 */
    436 		memset(&cmd, 0, sizeof(cmd));
    437 		cmd.opcode = MUSTEK_START_STOP;
    438 		cmd.mode = MUSTEK_SCAN_STOP;
    439 
    440 		/* send the command to the scanner */
    441 		SC_DEBUG(periph, SCSIPI_DB1,
    442 		    ("mustek_rewind_scanner: stop_scan\n"));
    443 		error = scsipi_command(periph,
    444 		    (void *)&cmd, sizeof(cmd),
    445 		    NULL, 0,
    446 		    MUSTEK_RETRIES, 5000, NULL, 0);
    447 		if (error)
    448 			return (error);
    449 	}
    450 
    451 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_rewind_scanner: end\n"));
    452 
    453 	return (0);
    454 }
    455 
    456 /*
    457  * read the requested number of bytes/lines from the scanner
    458  */
    459 static int
    460 mustek_read(struct ss_softc *ss, struct buf *bp)
    461 {
    462 	struct mustek_read_cmd cmd;
    463 	struct scsipi_xfer *xs;
    464 	struct scsipi_periph *periph = ss->sc_periph;
    465 	u_long lines_to_read;
    466 	int error;
    467 
    468 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_read: start\n"));
    469 
    470 	memset(&cmd, 0, sizeof(cmd));
    471 	cmd.opcode = MUSTEK_READ;
    472 
    473 	/* instead of the bytes, the mustek wants the number of lines */
    474 	lines_to_read = bp->b_bcount /
    475 	    ((ss->sio.scan_pixels_per_line * ss->sio.scan_bits_per_pixel) / 8);
    476 	SC_DEBUG(periph, SCSIPI_DB1, ("mustek_read: read %ld lines\n",
    477 	    lines_to_read));
    478 	_lto3b(lines_to_read, cmd.length);
    479 
    480 	/*
    481 	 * go ask the adapter to do all this for us
    482 	 */
    483 	xs = scsipi_make_xs(periph,
    484 	    (struct scsipi_generic *) &cmd, sizeof(cmd),
    485 	    (u_char *) bp->b_data, bp->b_bcount,
    486 	    MUSTEK_RETRIES, 10000, bp,
    487 	    XS_CTL_NOSLEEP | XS_CTL_ASYNC | XS_CTL_DATA_IN);
    488 	if (xs == NULL) {
    489 		/*
    490 		 * out of memory. Keep this buffer in the queue, and
    491 		 * retry later.
    492 		 */
    493 		callout_reset(&ss->sc_callout, hz / 2, ssrestart,
    494 		    periph);
    495 		return(0);
    496 	}
    497 #ifdef DIAGNOSTIC
    498 	if (BUFQ_GET(&ss->buf_queue) != bp)
    499 		panic("ssstart(): dequeued wrong buf");
    500 #else
    501 	BUFQ_GET(&ss->buf_queue);
    502 #endif
    503 	error = scsipi_execute_xs(xs);
    504 	/* with a scsipi_xfer preallocated, scsipi_command can't fail */
    505 	KASSERT(error == 0);
    506 	ss->sio.scan_lines -= lines_to_read;
    507 	if (ss->sio.scan_lines < 0)
    508 		ss->sio.scan_lines = 0;
    509 	ss->sio.scan_window_size -= bp->b_bcount;
    510 	if (ss->sio.scan_window_size < 0)
    511 		ss->sio.scan_window_size = 0;
    512 	return (0);
    513 }
    514 
    515 /*
    516  * check if the scanner is ready to take commands
    517  *   wait timeout seconds and try only every second
    518  *   if update, then update picture size info
    519  *
    520  *   returns EBUSY if scanner not ready
    521  */
    522 static int
    523 mustek_get_status(struct ss_softc *ss, int timeout, int update)
    524 {
    525 	struct mustek_get_status_cmd cmd;
    526 	struct mustek_get_status_data data;
    527 	struct scsipi_periph *periph = ss->sc_periph;
    528 	int error, lines, bytes_per_line;
    529 
    530 	memset(&cmd, 0, sizeof(cmd));
    531 	cmd.opcode = MUSTEK_GET_STATUS;
    532 	cmd.length = sizeof(data);
    533 
    534 	while (1) {
    535 		SC_DEBUG(periph, SCSIPI_DB1, ("mustek_get_status: stat_cmd\n"));
    536 		error = scsipi_command(periph, (void *)&cmd, sizeof(cmd),
    537 		    (void *)&data, sizeof(data),
    538 		    MUSTEK_RETRIES, 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 static void
    582 mustek_compute_sizes(struct ss_softc *ss)
    583 {
    584 
    585 	switch (ss->sio.scan_image_mode) {
    586 	case SIM_BINARY_MONOCHROME:
    587 	case SIM_DITHERED_MONOCHROME:
    588 		ss->sio.scan_bits_per_pixel = 1;
    589 		break;
    590 	case SIM_GRAYSCALE:
    591 	case SIM_RED:
    592 	case SIM_GREEN:
    593 	case SIM_BLUE:
    594 		ss->sio.scan_bits_per_pixel = 8;
    595 		break;
    596 	}
    597 
    598 	/*
    599 	 * horizontal number of bytes is always a multiple of 2,
    600 	 * in 8-bit mode at least
    601 	 */
    602 	ss->sio.scan_pixels_per_line =
    603 	    (ss->sio.scan_width * ss->sio.scan_x_resolution) / 1200;
    604 	if (ss->sio.scan_bits_per_pixel == 1)
    605 		/* make it a multiple of 16, and thus of 2 bytes */
    606 		ss->sio.scan_pixels_per_line =
    607 		    (ss->sio.scan_pixels_per_line + 15) & 0xfffffff0;
    608 	else
    609 		ss->sio.scan_pixels_per_line =
    610 		    (ss->sio.scan_pixels_per_line + 1) & 0xfffffffe;
    611 
    612 	ss->sio.scan_lines =
    613 	    (ss->sio.scan_height * ss->sio.scan_y_resolution) / 1200;
    614 	ss->sio.scan_window_size = ss->sio.scan_lines *
    615 	    ((ss->sio.scan_pixels_per_line * ss->sio.scan_bits_per_pixel) / 8);
    616 }
    617