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>
51 MODULE_AUTHOR("Michael Geng <linux@MichaelGeng.de>");
52 MODULE_DESCRIPTION("Philips SAA5246A, SAA5281 Teletext decoder driver");
53 MODULE_LICENSE("GPL");
55 struct saa5246a_device
57 u8 pgbuf[NUM_DAUS][VTX_VIRTUALSIZE];
58 int is_searching[NUM_DAUS];
59 struct i2c_client *client;
60 struct semaphore lock;
63 static struct video_device saa_template; /* Declared near bottom */
65 /* Addresses to scan */
66 static unsigned short normal_i2c[] = { I2C_ADDRESS, I2C_CLIENT_END };
69 static struct i2c_client client_template;
71 static int saa5246a_attach(struct i2c_adapter *adap, int addr, int kind)
75 struct i2c_client *client;
76 struct video_device *vd;
77 struct saa5246a_device *t;
79 printk(KERN_INFO "saa5246a: teletext chip found.\n");
80 client=kmalloc(sizeof(*client), GFP_KERNEL);
83 client_template.adapter = adap;
84 client_template.addr = addr;
85 memcpy(client, &client_template, sizeof(*client));
86 t = kmalloc(sizeof(*t), GFP_KERNEL);
92 memset(t, 0, sizeof(*t));
93 strlcpy(client->name, IF_NAME, I2C_NAME_SIZE);
97 * Now create a video4linux device
100 vd = video_device_alloc();
107 i2c_set_clientdata(client, vd);
108 memcpy(vd, &saa_template, sizeof(*vd));
110 for (pgbuf = 0; pgbuf < NUM_DAUS; pgbuf++)
112 memset(t->pgbuf[pgbuf], ' ', sizeof(t->pgbuf[0]));
113 t->is_searching[pgbuf] = FALSE;
122 if((err=video_register_device(vd, VFL_TYPE_VTX,-1))<0)
126 video_device_release(vd);
130 i2c_attach_client(client);
135 * We do most of the hard work when we become a device on the i2c.
137 static int saa5246a_probe(struct i2c_adapter *adap)
139 if (adap->class & I2C_CLASS_TV_ANALOG)
140 return i2c_probe(adap, &addr_data, saa5246a_attach);
144 static int saa5246a_detach(struct i2c_client *client)
146 struct video_device *vd = i2c_get_clientdata(client);
147 i2c_detach_client(client);
148 video_unregister_device(vd);
154 static int saa5246a_command(struct i2c_client *device, unsigned int cmd,
164 static struct i2c_driver i2c_driver_videotext =
167 .owner = THIS_MODULE,
168 .name = IF_NAME, /* name */
170 .id = I2C_DRIVERID_SAA5249, /* in i2c.h */
171 .attach_adapter = saa5246a_probe,
172 .detach_client = saa5246a_detach,
173 .command = saa5246a_command
176 static struct i2c_client client_template = {
177 .driver = &i2c_driver_videotext,
181 static int i2c_sendbuf(struct saa5246a_device *t, int reg, int count, u8 *data)
186 memcpy(buf+1, data, count);
188 if(i2c_master_send(t->client, buf, count+1)==count+1)
193 static int i2c_senddata(struct saa5246a_device *t, ...)
195 unsigned char buf[64];
201 while((v=va_arg(argp,int))!=-1)
203 return i2c_sendbuf(t, buf[0], ct-1, buf+1);
206 /* Get count number of bytes from I²C-device at address adr, store them in buf.
207 * Start & stop handshaking is done by this routine, ack will be sent after the
208 * last byte to inhibit further sending of data. If uaccess is TRUE, data is
209 * written to user-space with put_user. Returns -1 if I²C-device didn't send
210 * acknowledge, 0 otherwise
212 static int i2c_getdata(struct saa5246a_device *t, int count, u8 *buf)
214 if(i2c_master_recv(t->client, buf, count)!=count)
219 /* When a page is found then the not FOUND bit in one of the status registers
220 * of the SAA5264A chip is cleared. Unfortunately this bit is not set
221 * automatically when a new page is requested. Instead this function must be
222 * called after a page has been requested.
224 * Return value: 0 if successful
226 static int saa5246a_clear_found_bit(struct saa5246a_device *t,
227 unsigned char dau_no)
229 unsigned char row_25_column_8;
231 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
234 R8_DO_NOT_CLEAR_MEMORY,
241 i2c_getdata(t, 1, &row_25_column_8))
245 row_25_column_8 |= ROW25_COLUMN8_PAGE_NOT_FOUND;
246 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
249 R8_DO_NOT_CLEAR_MEMORY,
265 /* Requests one videotext page as described in req. The fields of req are
266 * checked and an error is returned if something is invalid.
268 * Return value: 0 if successful
270 static int saa5246a_request_page(struct saa5246a_device *t,
273 if (req->pagemask < 0 || req->pagemask >= PGMASK_MAX)
275 if (req->pagemask & PGMASK_PAGE)
276 if (req->page < 0 || req->page > PAGE_MAX)
278 if (req->pagemask & PGMASK_HOUR)
279 if (req->hour < 0 || req->hour > HOUR_MAX)
281 if (req->pagemask & PGMASK_MINUTE)
282 if (req->minute < 0 || req->minute > MINUTE_MAX)
284 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
287 if (i2c_senddata(t, SAA5246A_REGISTER_R2,
289 R2_IN_R3_SELECT_PAGE_HUNDREDS |
292 R2_HAMMING_CHECK_OFF,
294 HUNDREDS_OF_PAGE(req->page) |
296 (req->pagemask & PG_HUND ?
297 R3_PAGE_HUNDREDS_DO_CARE :
298 R3_PAGE_HUNDREDS_DO_NOT_CARE),
300 TENS_OF_PAGE(req->page) |
301 (req->pagemask & PG_TEN ?
302 R3_PAGE_TENS_DO_CARE :
303 R3_PAGE_TENS_DO_NOT_CARE),
305 UNITS_OF_PAGE(req->page) |
306 (req->pagemask & PG_UNIT ?
307 R3_PAGE_UNITS_DO_CARE :
308 R3_PAGE_UNITS_DO_NOT_CARE),
310 TENS_OF_HOUR(req->hour) |
311 (req->pagemask & HR_TEN ?
312 R3_HOURS_TENS_DO_CARE :
313 R3_HOURS_TENS_DO_NOT_CARE),
315 UNITS_OF_HOUR(req->hour) |
316 (req->pagemask & HR_UNIT ?
317 R3_HOURS_UNITS_DO_CARE :
318 R3_HOURS_UNITS_DO_NOT_CARE),
320 TENS_OF_MINUTE(req->minute) |
321 (req->pagemask & MIN_TEN ?
322 R3_MINUTES_TENS_DO_CARE :
323 R3_MINUTES_TENS_DO_NOT_CARE),
325 UNITS_OF_MINUTE(req->minute) |
326 (req->pagemask & MIN_UNIT ?
327 R3_MINUTES_UNITS_DO_CARE :
328 R3_MINUTES_UNITS_DO_NOT_CARE),
330 COMMAND_END) || i2c_senddata(t, SAA5246A_REGISTER_R2,
332 R2_IN_R3_SELECT_PAGE_HUNDREDS |
335 R2_HAMMING_CHECK_OFF,
337 HUNDREDS_OF_PAGE(req->page) |
339 (req->pagemask & PG_HUND ?
340 R3_PAGE_HUNDREDS_DO_CARE :
341 R3_PAGE_HUNDREDS_DO_NOT_CARE),
348 t->is_searching[req->pgbuf] = TRUE;
352 /* This routine decodes the page number from the infobits contained in line 25.
355 * infobits: must be bits 0 to 9 of column 25
357 * Return value: page number coded in hexadecimal, i. e. page 123 is coded 0x123
359 static inline int saa5246a_extract_pagenum_from_infobits(
360 unsigned char infobits[10])
362 int page_hundreds, page_tens, page_units;
364 page_units = infobits[0] & ROW25_COLUMN0_PAGE_UNITS;
365 page_tens = infobits[1] & ROW25_COLUMN1_PAGE_TENS;
366 page_hundreds = infobits[8] & ROW25_COLUMN8_PAGE_HUNDREDS;
368 /* page 0x.. means page 8.. */
369 if (page_hundreds == 0)
372 return((page_hundreds << 8) | (page_tens << 4) | page_units);
375 /* Decodes the hour from the infobits contained in line 25.
378 * infobits: must be bits 0 to 9 of column 25
380 * Return: hour coded in hexadecimal, i. e. 12h is coded 0x12
382 static inline int saa5246a_extract_hour_from_infobits(
383 unsigned char infobits[10])
385 int hour_tens, hour_units;
387 hour_units = infobits[4] & ROW25_COLUMN4_HOUR_UNITS;
388 hour_tens = infobits[5] & ROW25_COLUMN5_HOUR_TENS;
390 return((hour_tens << 4) | hour_units);
393 /* Decodes the minutes from the infobits contained in line 25.
396 * infobits: must be bits 0 to 9 of column 25
398 * Return: minutes coded in hexadecimal, i. e. 10min is coded 0x10
400 static inline int saa5246a_extract_minutes_from_infobits(
401 unsigned char infobits[10])
403 int minutes_tens, minutes_units;
405 minutes_units = infobits[2] & ROW25_COLUMN2_MINUTES_UNITS;
406 minutes_tens = infobits[3] & ROW25_COLUMN3_MINUTES_TENS;
408 return((minutes_tens << 4) | minutes_units);
411 /* Reads the status bits contained in the first 10 columns of the first line
412 * and extracts the information into info.
414 * Return value: 0 if successful
416 static inline int saa5246a_get_status(struct saa5246a_device *t,
417 vtx_pageinfo_t *info, unsigned char dau_no)
419 unsigned char infobits[10];
422 if (dau_no >= NUM_DAUS)
425 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
428 R8_DO_NOT_CLEAR_MEMORY,
435 i2c_getdata(t, 10, infobits))
440 info->pagenum = saa5246a_extract_pagenum_from_infobits(infobits);
441 info->hour = saa5246a_extract_hour_from_infobits(infobits);
442 info->minute = saa5246a_extract_minutes_from_infobits(infobits);
443 info->charset = ((infobits[7] & ROW25_COLUMN7_CHARACTER_SET) >> 1);
444 info->delete = !!(infobits[3] & ROW25_COLUMN3_DELETE_PAGE);
445 info->headline = !!(infobits[5] & ROW25_COLUMN5_INSERT_HEADLINE);
446 info->subtitle = !!(infobits[5] & ROW25_COLUMN5_INSERT_SUBTITLE);
447 info->supp_header = !!(infobits[6] & ROW25_COLUMN6_SUPPRESS_HEADER);
448 info->update = !!(infobits[6] & ROW25_COLUMN6_UPDATE_PAGE);
449 info->inter_seq = !!(infobits[6] & ROW25_COLUMN6_INTERRUPTED_SEQUENCE);
450 info->dis_disp = !!(infobits[6] & ROW25_COLUMN6_SUPPRESS_DISPLAY);
451 info->serial = !!(infobits[7] & ROW25_COLUMN7_SERIAL_MODE);
452 info->notfound = !!(infobits[8] & ROW25_COLUMN8_PAGE_NOT_FOUND);
453 info->pblf = !!(infobits[9] & ROW25_COLUMN9_PAGE_BEING_LOOKED_FOR);
455 for (column = 0; column <= 7; column++) {
456 if (infobits[column] & ROW25_COLUMN0_TO_7_HAMMING_ERROR) {
461 if (!info->hamming && !info->notfound)
462 t->is_searching[dau_no] = FALSE;
466 /* Reads 1 videotext page buffer of the SAA5246A.
468 * req is used both as input and as output. It contains information which part
469 * must be read. The videotext page is copied into req->buffer.
471 * Return value: 0 if successful
473 static inline int saa5246a_get_page(struct saa5246a_device *t,
476 int start, end, size;
480 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS ||
481 req->start < 0 || req->start > req->end || req->end >= VTX_PAGESIZE)
484 buf = kmalloc(VTX_PAGESIZE, GFP_KERNEL);
488 /* Read "normal" part of page */
491 end = min(req->end, VTX_PAGESIZE - 1);
492 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
493 req->pgbuf | R8_DO_NOT_CLEAR_MEMORY,
494 ROW(req->start), COLUMN(req->start), COMMAND_END))
496 if (i2c_getdata(t, end - req->start + 1, buf))
499 if (copy_to_user(req->buffer, buf, end - req->start + 1))
502 /* Always get the time from buffer 4, since this stupid SAA5246A only
503 * updates the currently displayed buffer...
505 if (REQ_CONTAINS_TIME(req)) {
506 start = max(req->start, POS_TIME_START);
507 end = min(req->end, POS_TIME_END);
508 size = end - start + 1;
513 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
514 R8_ACTIVE_CHAPTER_4 | R8_DO_NOT_CLEAR_MEMORY,
515 R9_CURSER_ROW_0, start, COMMAND_END))
517 if (i2c_getdata(t, size, buf))
520 if (copy_to_user(req->buffer + start - req->start, buf, size))
523 /* Insert the header from buffer 4 only, if acquisition circuit is still searching for a page */
524 if (REQ_CONTAINS_HEADER(req) && t->is_searching[req->pgbuf]) {
525 start = max(req->start, POS_HEADER_START);
526 end = min(req->end, POS_HEADER_END);
527 size = end - start + 1;
532 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
533 R8_ACTIVE_CHAPTER_4 | R8_DO_NOT_CLEAR_MEMORY,
534 R9_CURSER_ROW_0, start, COMMAND_END))
536 if (i2c_getdata(t, end - start + 1, buf))
539 if (copy_to_user(req->buffer + start - req->start, buf, size))
548 /* Stops the acquisition circuit given in dau_no. The page buffer associated
549 * with this acquisition circuit will no more be updated. The other daus are
552 * Return value: 0 if successful
554 static inline int saa5246a_stop_dau(struct saa5246a_device *t,
555 unsigned char dau_no)
557 if (dau_no >= NUM_DAUS)
559 if (i2c_senddata(t, SAA5246A_REGISTER_R2,
561 R2_IN_R3_SELECT_PAGE_HUNDREDS |
564 R2_HAMMING_CHECK_OFF,
568 R3_PAGE_HUNDREDS_DO_NOT_CARE,
574 t->is_searching[dau_no] = FALSE;
578 /* Handles ioctls defined in videotext.h
580 * Returns 0 if successful
582 static int do_saa5246a_ioctl(struct inode *inode, struct file *file,
583 unsigned int cmd, void *arg)
585 struct video_device *vd = video_devdata(file);
586 struct saa5246a_device *t=vd->priv;
591 vtx_info_t *info = arg;
593 info->version_major = MAJOR_VERSION;
594 info->version_minor = MINOR_VERSION;
595 info->numpages = NUM_DAUS;
601 vtx_pagereq_t *req = arg;
603 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
605 memset(t->pgbuf[req->pgbuf], ' ', sizeof(t->pgbuf[0]));
611 vtx_pagereq_t *req = arg;
613 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
615 return(saa5246a_clear_found_bit(t, req->pgbuf));
620 vtx_pagereq_t *req = arg;
622 return(saa5246a_request_page(t, req));
627 vtx_pagereq_t *req = arg;
631 if ((rval = saa5246a_get_status(t, &info, req->pgbuf)))
633 if(copy_to_user(req->buffer, &info,
634 sizeof(vtx_pageinfo_t)))
641 vtx_pagereq_t *req = arg;
643 return(saa5246a_get_page(t, req));
648 vtx_pagereq_t *req = arg;
650 return(saa5246a_stop_dau(t, req->pgbuf));
665 /* I do not know what "virtual mode" means */
673 * Translates old vtx IOCTLs to new ones
675 * This keeps new kernel versions compatible with old userspace programs.
677 static inline unsigned int vtx_fix_command(unsigned int cmd)
680 case VTXIOCGETINFO_OLD:
683 case VTXIOCCLRPAGE_OLD:
686 case VTXIOCCLRFOUND_OLD:
687 cmd = VTXIOCCLRFOUND;
689 case VTXIOCPAGEREQ_OLD:
692 case VTXIOCGETSTAT_OLD:
695 case VTXIOCGETPAGE_OLD:
698 case VTXIOCSTOPDAU_OLD:
701 case VTXIOCPUTPAGE_OLD:
704 case VTXIOCSETDISP_OLD:
707 case VTXIOCPUTSTAT_OLD:
710 case VTXIOCCLRCACHE_OLD:
711 cmd = VTXIOCCLRCACHE;
713 case VTXIOCSETVIRT_OLD:
723 static int saa5246a_ioctl(struct inode *inode, struct file *file,
724 unsigned int cmd, unsigned long arg)
726 struct video_device *vd = video_devdata(file);
727 struct saa5246a_device *t = vd->priv;
730 cmd = vtx_fix_command(cmd);
732 err = video_usercopy(inode, file, cmd, arg, do_saa5246a_ioctl);
737 static int saa5246a_open(struct inode *inode, struct file *file)
739 struct video_device *vd = video_devdata(file);
740 struct saa5246a_device *t = vd->priv;
743 err = video_exclusive_open(inode,file);
747 if (t->client==NULL) {
752 if (i2c_senddata(t, SAA5246A_REGISTER_R0,
755 R0_PLL_TIME_CONSTANT_LONG |
756 R0_ENABLE_nODD_EVEN_OUTPUT |
758 R0_DO_NOT_FORCE_nODD_EVEN_LOW_IF_PICTURE_DISPLAYED |
760 R0_NO_AUTOMATIC_FASTEXT_PROMPT,
762 R1_NON_INTERLACED_312_312_LINES |
764 R1_EXTENDED_PACKET_DISABLE |
766 R1_8_BITS_NO_PARITY |
770 i2c_senddata(t, SAA5246A_REGISTER_R4,
772 /* We do not care much for the TV display but nevertheless we
773 * need the currently displayed page later because only on that
774 * page the time is updated. */
786 video_exclusive_release(inode,file);
790 static int saa5246a_release(struct inode *inode, struct file *file)
792 struct video_device *vd = video_devdata(file);
793 struct saa5246a_device *t = vd->priv;
795 /* Stop all acquisition circuits. */
796 i2c_senddata(t, SAA5246A_REGISTER_R1,
798 R1_INTERLACED_312_AND_HALF_312_AND_HALF_LINES |
800 R1_EXTENDED_PACKET_DISABLE |
802 R1_8_BITS_NO_PARITY |
806 video_exclusive_release(inode,file);
810 static int __init init_saa_5246a (void)
813 "SAA5246A (or compatible) Teletext decoder driver version %d.%d\n",
814 MAJOR_VERSION, MINOR_VERSION);
815 return i2c_add_driver(&i2c_driver_videotext);
818 static void __exit cleanup_saa_5246a (void)
820 i2c_del_driver(&i2c_driver_videotext);
823 module_init(init_saa_5246a);
824 module_exit(cleanup_saa_5246a);
826 static struct file_operations saa_fops = {
827 .owner = THIS_MODULE,
828 .open = saa5246a_open,
829 .release = saa5246a_release,
830 .ioctl = saa5246a_ioctl,
834 static struct video_device saa_template =
836 .owner = THIS_MODULE,
838 .type = VID_TYPE_TELETEXT,
839 .hardware = VID_HARDWARE_SAA5249,
841 .release = video_device_release,