2 * Driver for the SAA5246A or SAA5281 Teletext (=Videotext) decoder chips from
5 * Only capturing of Teletext pages is tested. The videotext chips also have a
6 * TV output but my hardware doesn't use it. For this reason this driver does
7 * not support changing any TV display settings.
9 * Copyright (C) 2004 Michael Geng <linux@MichaelGeng.de>
14 * Copyright (C) 1998 Richard Guenther
15 * <richard.guenther@student.uni-tuebingen.de>
18 * Alan Cox <Alan.Cox@linux.org>
23 * Copyright (C) 1994-97 Martin Buck <martin-2.buck@student.uni-ulm.de>
25 * This program is free software; you can redistribute it and/or modify
26 * it under the terms of the GNU General Public License as published by
27 * the Free Software Foundation; either version 2 of the License, or
28 * (at your option) any later version.
30 * This program is distributed in the hope that it will be useful,
31 * but WITHOUT ANY WARRANTY; without even the implied warranty of
32 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
33 * GNU General Public License for more details.
35 * You should have received a copy of the GNU General Public License
36 * along with this program; if not, write to the Free Software
37 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
41 #include <linux/module.h>
42 #include <linux/kernel.h>
43 #include <linux/sched.h>
45 #include <linux/init.h>
46 #include <linux/i2c.h>
47 #include <linux/videotext.h>
48 #include <linux/videodev.h>
49 #include <linux/mutex.h>
53 MODULE_AUTHOR("Michael Geng <linux@MichaelGeng.de>");
54 MODULE_DESCRIPTION("Philips SAA5246A, SAA5281 Teletext decoder driver");
55 MODULE_LICENSE("GPL");
57 struct saa5246a_device
59 u8 pgbuf[NUM_DAUS][VTX_VIRTUALSIZE];
60 int is_searching[NUM_DAUS];
61 struct i2c_client *client;
65 static struct video_device saa_template; /* Declared near bottom */
67 /* Addresses to scan */
68 static unsigned short normal_i2c[] = { I2C_ADDRESS, I2C_CLIENT_END };
71 static struct i2c_client client_template;
73 static int saa5246a_attach(struct i2c_adapter *adap, int addr, int kind)
77 struct i2c_client *client;
78 struct video_device *vd;
79 struct saa5246a_device *t;
81 printk(KERN_INFO "saa5246a: teletext chip found.\n");
82 client=kmalloc(sizeof(*client), GFP_KERNEL);
85 client_template.adapter = adap;
86 client_template.addr = addr;
87 memcpy(client, &client_template, sizeof(*client));
88 t = kzalloc(sizeof(*t), GFP_KERNEL);
94 strlcpy(client->name, IF_NAME, I2C_NAME_SIZE);
98 * Now create a video4linux device
101 vd = video_device_alloc();
108 i2c_set_clientdata(client, vd);
109 memcpy(vd, &saa_template, sizeof(*vd));
111 for (pgbuf = 0; pgbuf < NUM_DAUS; pgbuf++)
113 memset(t->pgbuf[pgbuf], ' ', sizeof(t->pgbuf[0]));
114 t->is_searching[pgbuf] = FALSE;
123 if((err=video_register_device(vd, VFL_TYPE_VTX,-1))<0)
127 video_device_release(vd);
131 i2c_attach_client(client);
136 * We do most of the hard work when we become a device on the i2c.
138 static int saa5246a_probe(struct i2c_adapter *adap)
140 if (adap->class & I2C_CLASS_TV_ANALOG)
141 return i2c_probe(adap, &addr_data, saa5246a_attach);
145 static int saa5246a_detach(struct i2c_client *client)
147 struct video_device *vd = i2c_get_clientdata(client);
148 i2c_detach_client(client);
149 video_unregister_device(vd);
159 static struct i2c_driver i2c_driver_videotext =
162 .name = IF_NAME, /* name */
164 .id = I2C_DRIVERID_SAA5249, /* in i2c.h */
165 .attach_adapter = saa5246a_probe,
166 .detach_client = saa5246a_detach,
169 static struct i2c_client client_template = {
170 .driver = &i2c_driver_videotext,
174 static int i2c_sendbuf(struct saa5246a_device *t, int reg, int count, u8 *data)
179 memcpy(buf+1, data, count);
181 if(i2c_master_send(t->client, buf, count+1)==count+1)
186 static int i2c_senddata(struct saa5246a_device *t, ...)
188 unsigned char buf[64];
194 while((v=va_arg(argp,int))!=-1)
196 return i2c_sendbuf(t, buf[0], ct-1, buf+1);
199 /* Get count number of bytes from I²C-device at address adr, store them in buf.
200 * Start & stop handshaking is done by this routine, ack will be sent after the
201 * last byte to inhibit further sending of data. If uaccess is TRUE, data is
202 * written to user-space with put_user. Returns -1 if I²C-device didn't send
203 * acknowledge, 0 otherwise
205 static int i2c_getdata(struct saa5246a_device *t, int count, u8 *buf)
207 if(i2c_master_recv(t->client, buf, count)!=count)
212 /* When a page is found then the not FOUND bit in one of the status registers
213 * of the SAA5264A chip is cleared. Unfortunately this bit is not set
214 * automatically when a new page is requested. Instead this function must be
215 * called after a page has been requested.
217 * Return value: 0 if successful
219 static int saa5246a_clear_found_bit(struct saa5246a_device *t,
220 unsigned char dau_no)
222 unsigned char row_25_column_8;
224 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
227 R8_DO_NOT_CLEAR_MEMORY,
234 i2c_getdata(t, 1, &row_25_column_8))
238 row_25_column_8 |= ROW25_COLUMN8_PAGE_NOT_FOUND;
239 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
242 R8_DO_NOT_CLEAR_MEMORY,
258 /* Requests one videotext page as described in req. The fields of req are
259 * checked and an error is returned if something is invalid.
261 * Return value: 0 if successful
263 static int saa5246a_request_page(struct saa5246a_device *t,
266 if (req->pagemask < 0 || req->pagemask >= PGMASK_MAX)
268 if (req->pagemask & PGMASK_PAGE)
269 if (req->page < 0 || req->page > PAGE_MAX)
271 if (req->pagemask & PGMASK_HOUR)
272 if (req->hour < 0 || req->hour > HOUR_MAX)
274 if (req->pagemask & PGMASK_MINUTE)
275 if (req->minute < 0 || req->minute > MINUTE_MAX)
277 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
280 if (i2c_senddata(t, SAA5246A_REGISTER_R2,
282 R2_IN_R3_SELECT_PAGE_HUNDREDS |
285 R2_HAMMING_CHECK_OFF,
287 HUNDREDS_OF_PAGE(req->page) |
289 (req->pagemask & PG_HUND ?
290 R3_PAGE_HUNDREDS_DO_CARE :
291 R3_PAGE_HUNDREDS_DO_NOT_CARE),
293 TENS_OF_PAGE(req->page) |
294 (req->pagemask & PG_TEN ?
295 R3_PAGE_TENS_DO_CARE :
296 R3_PAGE_TENS_DO_NOT_CARE),
298 UNITS_OF_PAGE(req->page) |
299 (req->pagemask & PG_UNIT ?
300 R3_PAGE_UNITS_DO_CARE :
301 R3_PAGE_UNITS_DO_NOT_CARE),
303 TENS_OF_HOUR(req->hour) |
304 (req->pagemask & HR_TEN ?
305 R3_HOURS_TENS_DO_CARE :
306 R3_HOURS_TENS_DO_NOT_CARE),
308 UNITS_OF_HOUR(req->hour) |
309 (req->pagemask & HR_UNIT ?
310 R3_HOURS_UNITS_DO_CARE :
311 R3_HOURS_UNITS_DO_NOT_CARE),
313 TENS_OF_MINUTE(req->minute) |
314 (req->pagemask & MIN_TEN ?
315 R3_MINUTES_TENS_DO_CARE :
316 R3_MINUTES_TENS_DO_NOT_CARE),
318 UNITS_OF_MINUTE(req->minute) |
319 (req->pagemask & MIN_UNIT ?
320 R3_MINUTES_UNITS_DO_CARE :
321 R3_MINUTES_UNITS_DO_NOT_CARE),
323 COMMAND_END) || i2c_senddata(t, SAA5246A_REGISTER_R2,
325 R2_IN_R3_SELECT_PAGE_HUNDREDS |
328 R2_HAMMING_CHECK_OFF,
330 HUNDREDS_OF_PAGE(req->page) |
332 (req->pagemask & PG_HUND ?
333 R3_PAGE_HUNDREDS_DO_CARE :
334 R3_PAGE_HUNDREDS_DO_NOT_CARE),
341 t->is_searching[req->pgbuf] = TRUE;
345 /* This routine decodes the page number from the infobits contained in line 25.
348 * infobits: must be bits 0 to 9 of column 25
350 * Return value: page number coded in hexadecimal, i. e. page 123 is coded 0x123
352 static inline int saa5246a_extract_pagenum_from_infobits(
353 unsigned char infobits[10])
355 int page_hundreds, page_tens, page_units;
357 page_units = infobits[0] & ROW25_COLUMN0_PAGE_UNITS;
358 page_tens = infobits[1] & ROW25_COLUMN1_PAGE_TENS;
359 page_hundreds = infobits[8] & ROW25_COLUMN8_PAGE_HUNDREDS;
361 /* page 0x.. means page 8.. */
362 if (page_hundreds == 0)
365 return((page_hundreds << 8) | (page_tens << 4) | page_units);
368 /* Decodes the hour from the infobits contained in line 25.
371 * infobits: must be bits 0 to 9 of column 25
373 * Return: hour coded in hexadecimal, i. e. 12h is coded 0x12
375 static inline int saa5246a_extract_hour_from_infobits(
376 unsigned char infobits[10])
378 int hour_tens, hour_units;
380 hour_units = infobits[4] & ROW25_COLUMN4_HOUR_UNITS;
381 hour_tens = infobits[5] & ROW25_COLUMN5_HOUR_TENS;
383 return((hour_tens << 4) | hour_units);
386 /* Decodes the minutes from the infobits contained in line 25.
389 * infobits: must be bits 0 to 9 of column 25
391 * Return: minutes coded in hexadecimal, i. e. 10min is coded 0x10
393 static inline int saa5246a_extract_minutes_from_infobits(
394 unsigned char infobits[10])
396 int minutes_tens, minutes_units;
398 minutes_units = infobits[2] & ROW25_COLUMN2_MINUTES_UNITS;
399 minutes_tens = infobits[3] & ROW25_COLUMN3_MINUTES_TENS;
401 return((minutes_tens << 4) | minutes_units);
404 /* Reads the status bits contained in the first 10 columns of the first line
405 * and extracts the information into info.
407 * Return value: 0 if successful
409 static inline int saa5246a_get_status(struct saa5246a_device *t,
410 vtx_pageinfo_t *info, unsigned char dau_no)
412 unsigned char infobits[10];
415 if (dau_no >= NUM_DAUS)
418 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
421 R8_DO_NOT_CLEAR_MEMORY,
428 i2c_getdata(t, 10, infobits))
433 info->pagenum = saa5246a_extract_pagenum_from_infobits(infobits);
434 info->hour = saa5246a_extract_hour_from_infobits(infobits);
435 info->minute = saa5246a_extract_minutes_from_infobits(infobits);
436 info->charset = ((infobits[7] & ROW25_COLUMN7_CHARACTER_SET) >> 1);
437 info->delete = !!(infobits[3] & ROW25_COLUMN3_DELETE_PAGE);
438 info->headline = !!(infobits[5] & ROW25_COLUMN5_INSERT_HEADLINE);
439 info->subtitle = !!(infobits[5] & ROW25_COLUMN5_INSERT_SUBTITLE);
440 info->supp_header = !!(infobits[6] & ROW25_COLUMN6_SUPPRESS_HEADER);
441 info->update = !!(infobits[6] & ROW25_COLUMN6_UPDATE_PAGE);
442 info->inter_seq = !!(infobits[6] & ROW25_COLUMN6_INTERRUPTED_SEQUENCE);
443 info->dis_disp = !!(infobits[6] & ROW25_COLUMN6_SUPPRESS_DISPLAY);
444 info->serial = !!(infobits[7] & ROW25_COLUMN7_SERIAL_MODE);
445 info->notfound = !!(infobits[8] & ROW25_COLUMN8_PAGE_NOT_FOUND);
446 info->pblf = !!(infobits[9] & ROW25_COLUMN9_PAGE_BEING_LOOKED_FOR);
448 for (column = 0; column <= 7; column++) {
449 if (infobits[column] & ROW25_COLUMN0_TO_7_HAMMING_ERROR) {
454 if (!info->hamming && !info->notfound)
455 t->is_searching[dau_no] = FALSE;
459 /* Reads 1 videotext page buffer of the SAA5246A.
461 * req is used both as input and as output. It contains information which part
462 * must be read. The videotext page is copied into req->buffer.
464 * Return value: 0 if successful
466 static inline int saa5246a_get_page(struct saa5246a_device *t,
469 int start, end, size;
473 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS ||
474 req->start < 0 || req->start > req->end || req->end >= VTX_PAGESIZE)
477 buf = kmalloc(VTX_PAGESIZE, GFP_KERNEL);
481 /* Read "normal" part of page */
484 end = min(req->end, VTX_PAGESIZE - 1);
485 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
486 req->pgbuf | R8_DO_NOT_CLEAR_MEMORY,
487 ROW(req->start), COLUMN(req->start), COMMAND_END))
489 if (i2c_getdata(t, end - req->start + 1, buf))
492 if (copy_to_user(req->buffer, buf, end - req->start + 1))
495 /* Always get the time from buffer 4, since this stupid SAA5246A only
496 * updates the currently displayed buffer...
498 if (REQ_CONTAINS_TIME(req)) {
499 start = max(req->start, POS_TIME_START);
500 end = min(req->end, POS_TIME_END);
501 size = end - start + 1;
506 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
507 R8_ACTIVE_CHAPTER_4 | R8_DO_NOT_CLEAR_MEMORY,
508 R9_CURSER_ROW_0, start, COMMAND_END))
510 if (i2c_getdata(t, size, buf))
513 if (copy_to_user(req->buffer + start - req->start, buf, size))
516 /* Insert the header from buffer 4 only, if acquisition circuit is still searching for a page */
517 if (REQ_CONTAINS_HEADER(req) && t->is_searching[req->pgbuf]) {
518 start = max(req->start, POS_HEADER_START);
519 end = min(req->end, POS_HEADER_END);
520 size = end - start + 1;
525 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
526 R8_ACTIVE_CHAPTER_4 | R8_DO_NOT_CLEAR_MEMORY,
527 R9_CURSER_ROW_0, start, COMMAND_END))
529 if (i2c_getdata(t, end - start + 1, buf))
532 if (copy_to_user(req->buffer + start - req->start, buf, size))
541 /* Stops the acquisition circuit given in dau_no. The page buffer associated
542 * with this acquisition circuit will no more be updated. The other daus are
545 * Return value: 0 if successful
547 static inline int saa5246a_stop_dau(struct saa5246a_device *t,
548 unsigned char dau_no)
550 if (dau_no >= NUM_DAUS)
552 if (i2c_senddata(t, SAA5246A_REGISTER_R2,
554 R2_IN_R3_SELECT_PAGE_HUNDREDS |
557 R2_HAMMING_CHECK_OFF,
561 R3_PAGE_HUNDREDS_DO_NOT_CARE,
567 t->is_searching[dau_no] = FALSE;
571 /* Handles ioctls defined in videotext.h
573 * Returns 0 if successful
575 static int do_saa5246a_ioctl(struct inode *inode, struct file *file,
576 unsigned int cmd, void *arg)
578 struct video_device *vd = video_devdata(file);
579 struct saa5246a_device *t=vd->priv;
584 vtx_info_t *info = arg;
586 info->version_major = MAJOR_VERSION;
587 info->version_minor = MINOR_VERSION;
588 info->numpages = NUM_DAUS;
594 vtx_pagereq_t *req = arg;
596 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
598 memset(t->pgbuf[req->pgbuf], ' ', sizeof(t->pgbuf[0]));
604 vtx_pagereq_t *req = arg;
606 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
608 return(saa5246a_clear_found_bit(t, req->pgbuf));
613 vtx_pagereq_t *req = arg;
615 return(saa5246a_request_page(t, req));
620 vtx_pagereq_t *req = arg;
624 if ((rval = saa5246a_get_status(t, &info, req->pgbuf)))
626 if(copy_to_user(req->buffer, &info,
627 sizeof(vtx_pageinfo_t)))
634 vtx_pagereq_t *req = arg;
636 return(saa5246a_get_page(t, req));
641 vtx_pagereq_t *req = arg;
643 return(saa5246a_stop_dau(t, req->pgbuf));
658 /* I do not know what "virtual mode" means */
666 * Translates old vtx IOCTLs to new ones
668 * This keeps new kernel versions compatible with old userspace programs.
670 static inline unsigned int vtx_fix_command(unsigned int cmd)
673 case VTXIOCGETINFO_OLD:
676 case VTXIOCCLRPAGE_OLD:
679 case VTXIOCCLRFOUND_OLD:
680 cmd = VTXIOCCLRFOUND;
682 case VTXIOCPAGEREQ_OLD:
685 case VTXIOCGETSTAT_OLD:
688 case VTXIOCGETPAGE_OLD:
691 case VTXIOCSTOPDAU_OLD:
694 case VTXIOCPUTPAGE_OLD:
697 case VTXIOCSETDISP_OLD:
700 case VTXIOCPUTSTAT_OLD:
703 case VTXIOCCLRCACHE_OLD:
704 cmd = VTXIOCCLRCACHE;
706 case VTXIOCSETVIRT_OLD:
716 static int saa5246a_ioctl(struct inode *inode, struct file *file,
717 unsigned int cmd, unsigned long arg)
719 struct video_device *vd = video_devdata(file);
720 struct saa5246a_device *t = vd->priv;
723 cmd = vtx_fix_command(cmd);
724 mutex_lock(&t->lock);
725 err = video_usercopy(inode, file, cmd, arg, do_saa5246a_ioctl);
726 mutex_unlock(&t->lock);
730 static int saa5246a_open(struct inode *inode, struct file *file)
732 struct video_device *vd = video_devdata(file);
733 struct saa5246a_device *t = vd->priv;
736 err = video_exclusive_open(inode,file);
740 if (t->client==NULL) {
745 if (i2c_senddata(t, SAA5246A_REGISTER_R0,
748 R0_PLL_TIME_CONSTANT_LONG |
749 R0_ENABLE_nODD_EVEN_OUTPUT |
751 R0_DO_NOT_FORCE_nODD_EVEN_LOW_IF_PICTURE_DISPLAYED |
753 R0_NO_AUTOMATIC_FASTEXT_PROMPT,
755 R1_NON_INTERLACED_312_312_LINES |
757 R1_EXTENDED_PACKET_DISABLE |
759 R1_8_BITS_NO_PARITY |
763 i2c_senddata(t, SAA5246A_REGISTER_R4,
765 /* We do not care much for the TV display but nevertheless we
766 * need the currently displayed page later because only on that
767 * page the time is updated. */
779 video_exclusive_release(inode,file);
783 static int saa5246a_release(struct inode *inode, struct file *file)
785 struct video_device *vd = video_devdata(file);
786 struct saa5246a_device *t = vd->priv;
788 /* Stop all acquisition circuits. */
789 i2c_senddata(t, SAA5246A_REGISTER_R1,
791 R1_INTERLACED_312_AND_HALF_312_AND_HALF_LINES |
793 R1_EXTENDED_PACKET_DISABLE |
795 R1_8_BITS_NO_PARITY |
799 video_exclusive_release(inode,file);
803 static int __init init_saa_5246a (void)
806 "SAA5246A (or compatible) Teletext decoder driver version %d.%d\n",
807 MAJOR_VERSION, MINOR_VERSION);
808 return i2c_add_driver(&i2c_driver_videotext);
811 static void __exit cleanup_saa_5246a (void)
813 i2c_del_driver(&i2c_driver_videotext);
816 module_init(init_saa_5246a);
817 module_exit(cleanup_saa_5246a);
819 static struct file_operations saa_fops = {
820 .owner = THIS_MODULE,
821 .open = saa5246a_open,
822 .release = saa5246a_release,
823 .ioctl = saa5246a_ioctl,
827 static struct video_device saa_template =
829 .owner = THIS_MODULE,
831 .type = VID_TYPE_TELETEXT,
832 .hardware = VID_HARDWARE_SAA5249,
834 .release = video_device_release,