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 };
67 static unsigned short normal_i2c_range[] = { I2C_CLIENT_END };
68 static unsigned short probe[2] = { I2C_CLIENT_END, I2C_CLIENT_END };
69 static unsigned short probe_range[2] = { I2C_CLIENT_END, I2C_CLIENT_END };
70 static unsigned short ignore[2] = { I2C_CLIENT_END, I2C_CLIENT_END };
71 static unsigned short ignore_range[2] = { I2C_CLIENT_END, I2C_CLIENT_END };
72 static unsigned short force[2] = { I2C_CLIENT_END, I2C_CLIENT_END };
74 static struct i2c_client_address_data addr_data = {
75 normal_i2c, normal_i2c_range,
81 static struct i2c_client client_template;
83 static int saa5246a_attach(struct i2c_adapter *adap, int addr, int kind)
87 struct i2c_client *client;
88 struct video_device *vd;
89 struct saa5246a_device *t;
91 printk(KERN_INFO "saa5246a: teletext chip found.\n");
92 client=kmalloc(sizeof(*client), GFP_KERNEL);
95 client_template.adapter = adap;
96 client_template.addr = addr;
97 memcpy(client, &client_template, sizeof(*client));
98 t = kmalloc(sizeof(*t), GFP_KERNEL);
104 memset(t, 0, sizeof(*t));
105 strlcpy(client->name, IF_NAME, I2C_NAME_SIZE);
106 init_MUTEX(&t->lock);
109 * Now create a video4linux device
112 vd = video_device_alloc();
119 i2c_set_clientdata(client, vd);
120 memcpy(vd, &saa_template, sizeof(*vd));
122 for (pgbuf = 0; pgbuf < NUM_DAUS; pgbuf++)
124 memset(t->pgbuf[pgbuf], ' ', sizeof(t->pgbuf[0]));
125 t->is_searching[pgbuf] = FALSE;
134 if((err=video_register_device(vd, VFL_TYPE_VTX,-1))<0)
138 video_device_release(vd);
142 i2c_attach_client(client);
147 * We do most of the hard work when we become a device on the i2c.
149 static int saa5246a_probe(struct i2c_adapter *adap)
151 if (adap->class & I2C_CLASS_TV_ANALOG)
152 return i2c_probe(adap, &addr_data, saa5246a_attach);
156 static int saa5246a_detach(struct i2c_client *client)
158 struct video_device *vd = i2c_get_clientdata(client);
159 i2c_detach_client(client);
160 video_unregister_device(vd);
166 static int saa5246a_command(struct i2c_client *device, unsigned int cmd,
176 static struct i2c_driver i2c_driver_videotext =
178 .owner = THIS_MODULE,
179 .name = IF_NAME, /* name */
180 .id = I2C_DRIVERID_SAA5249, /* in i2c.h */
181 .flags = I2C_DF_NOTIFY,
182 .attach_adapter = saa5246a_probe,
183 .detach_client = saa5246a_detach,
184 .command = saa5246a_command
187 static struct i2c_client client_template = {
189 .driver = &i2c_driver_videotext,
193 static int i2c_sendbuf(struct saa5246a_device *t, int reg, int count, u8 *data)
198 memcpy(buf+1, data, count);
200 if(i2c_master_send(t->client, buf, count+1)==count+1)
205 static int i2c_senddata(struct saa5246a_device *t, ...)
207 unsigned char buf[64];
213 while((v=va_arg(argp,int))!=-1)
215 return i2c_sendbuf(t, buf[0], ct-1, buf+1);
218 /* Get count number of bytes from I²C-device at address adr, store them in buf.
219 * Start & stop handshaking is done by this routine, ack will be sent after the
220 * last byte to inhibit further sending of data. If uaccess is TRUE, data is
221 * written to user-space with put_user. Returns -1 if I²C-device didn't send
222 * acknowledge, 0 otherwise
224 static int i2c_getdata(struct saa5246a_device *t, int count, u8 *buf)
226 if(i2c_master_recv(t->client, buf, count)!=count)
231 /* When a page is found then the not FOUND bit in one of the status registers
232 * of the SAA5264A chip is cleared. Unfortunately this bit is not set
233 * automatically when a new page is requested. Instead this function must be
234 * called after a page has been requested.
236 * Return value: 0 if successful
238 static int saa5246a_clear_found_bit(struct saa5246a_device *t,
239 unsigned char dau_no)
241 unsigned char row_25_column_8;
243 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
246 R8_DO_NOT_CLEAR_MEMORY,
253 i2c_getdata(t, 1, &row_25_column_8))
257 row_25_column_8 |= ROW25_COLUMN8_PAGE_NOT_FOUND;
258 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
261 R8_DO_NOT_CLEAR_MEMORY,
277 /* Requests one videotext page as described in req. The fields of req are
278 * checked and an error is returned if something is invalid.
280 * Return value: 0 if successful
282 static int saa5246a_request_page(struct saa5246a_device *t,
285 if (req->pagemask < 0 || req->pagemask >= PGMASK_MAX)
287 if (req->pagemask & PGMASK_PAGE)
288 if (req->page < 0 || req->page > PAGE_MAX)
290 if (req->pagemask & PGMASK_HOUR)
291 if (req->hour < 0 || req->hour > HOUR_MAX)
293 if (req->pagemask & PGMASK_MINUTE)
294 if (req->minute < 0 || req->minute > MINUTE_MAX)
296 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
299 if (i2c_senddata(t, SAA5246A_REGISTER_R2,
301 R2_IN_R3_SELECT_PAGE_HUNDREDS |
304 R2_HAMMING_CHECK_OFF,
306 HUNDREDS_OF_PAGE(req->page) |
308 (req->pagemask & PG_HUND ?
309 R3_PAGE_HUNDREDS_DO_CARE :
310 R3_PAGE_HUNDREDS_DO_NOT_CARE),
312 TENS_OF_PAGE(req->page) |
313 (req->pagemask & PG_TEN ?
314 R3_PAGE_TENS_DO_CARE :
315 R3_PAGE_TENS_DO_NOT_CARE),
317 UNITS_OF_PAGE(req->page) |
318 (req->pagemask & PG_UNIT ?
319 R3_PAGE_UNITS_DO_CARE :
320 R3_PAGE_UNITS_DO_NOT_CARE),
322 TENS_OF_HOUR(req->hour) |
323 (req->pagemask & HR_TEN ?
324 R3_HOURS_TENS_DO_CARE :
325 R3_HOURS_TENS_DO_NOT_CARE),
327 UNITS_OF_HOUR(req->hour) |
328 (req->pagemask & HR_UNIT ?
329 R3_HOURS_UNITS_DO_CARE :
330 R3_HOURS_UNITS_DO_NOT_CARE),
332 TENS_OF_MINUTE(req->minute) |
333 (req->pagemask & MIN_TEN ?
334 R3_MINUTES_TENS_DO_CARE :
335 R3_MINUTES_TENS_DO_NOT_CARE),
337 UNITS_OF_MINUTE(req->minute) |
338 (req->pagemask & MIN_UNIT ?
339 R3_MINUTES_UNITS_DO_CARE :
340 R3_MINUTES_UNITS_DO_NOT_CARE),
342 COMMAND_END) || i2c_senddata(t, SAA5246A_REGISTER_R2,
344 R2_IN_R3_SELECT_PAGE_HUNDREDS |
347 R2_HAMMING_CHECK_OFF,
349 HUNDREDS_OF_PAGE(req->page) |
351 (req->pagemask & PG_HUND ?
352 R3_PAGE_HUNDREDS_DO_CARE :
353 R3_PAGE_HUNDREDS_DO_NOT_CARE),
360 t->is_searching[req->pgbuf] = TRUE;
364 /* This routine decodes the page number from the infobits contained in line 25.
367 * infobits: must be bits 0 to 9 of column 25
369 * Return value: page number coded in hexadecimal, i. e. page 123 is coded 0x123
371 static inline int saa5246a_extract_pagenum_from_infobits(
372 unsigned char infobits[10])
374 int page_hundreds, page_tens, page_units;
376 page_units = infobits[0] & ROW25_COLUMN0_PAGE_UNITS;
377 page_tens = infobits[1] & ROW25_COLUMN1_PAGE_TENS;
378 page_hundreds = infobits[8] & ROW25_COLUMN8_PAGE_HUNDREDS;
380 /* page 0x.. means page 8.. */
381 if (page_hundreds == 0)
384 return((page_hundreds << 8) | (page_tens << 4) | page_units);
387 /* Decodes the hour from the infobits contained in line 25.
390 * infobits: must be bits 0 to 9 of column 25
392 * Return: hour coded in hexadecimal, i. e. 12h is coded 0x12
394 static inline int saa5246a_extract_hour_from_infobits(
395 unsigned char infobits[10])
397 int hour_tens, hour_units;
399 hour_units = infobits[4] & ROW25_COLUMN4_HOUR_UNITS;
400 hour_tens = infobits[5] & ROW25_COLUMN5_HOUR_TENS;
402 return((hour_tens << 4) | hour_units);
405 /* Decodes the minutes from the infobits contained in line 25.
408 * infobits: must be bits 0 to 9 of column 25
410 * Return: minutes coded in hexadecimal, i. e. 10min is coded 0x10
412 static inline int saa5246a_extract_minutes_from_infobits(
413 unsigned char infobits[10])
415 int minutes_tens, minutes_units;
417 minutes_units = infobits[2] & ROW25_COLUMN2_MINUTES_UNITS;
418 minutes_tens = infobits[3] & ROW25_COLUMN3_MINUTES_TENS;
420 return((minutes_tens << 4) | minutes_units);
423 /* Reads the status bits contained in the first 10 columns of the first line
424 * and extracts the information into info.
426 * Return value: 0 if successful
428 static inline int saa5246a_get_status(struct saa5246a_device *t,
429 vtx_pageinfo_t *info, unsigned char dau_no)
431 unsigned char infobits[10];
434 if (dau_no >= NUM_DAUS)
437 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
440 R8_DO_NOT_CLEAR_MEMORY,
447 i2c_getdata(t, 10, infobits))
452 info->pagenum = saa5246a_extract_pagenum_from_infobits(infobits);
453 info->hour = saa5246a_extract_hour_from_infobits(infobits);
454 info->minute = saa5246a_extract_minutes_from_infobits(infobits);
455 info->charset = ((infobits[7] & ROW25_COLUMN7_CHARACTER_SET) >> 1);
456 info->delete = !!(infobits[3] & ROW25_COLUMN3_DELETE_PAGE);
457 info->headline = !!(infobits[5] & ROW25_COLUMN5_INSERT_HEADLINE);
458 info->subtitle = !!(infobits[5] & ROW25_COLUMN5_INSERT_SUBTITLE);
459 info->supp_header = !!(infobits[6] & ROW25_COLUMN6_SUPPRESS_HEADER);
460 info->update = !!(infobits[6] & ROW25_COLUMN6_UPDATE_PAGE);
461 info->inter_seq = !!(infobits[6] & ROW25_COLUMN6_INTERRUPTED_SEQUENCE);
462 info->dis_disp = !!(infobits[6] & ROW25_COLUMN6_SUPPRESS_DISPLAY);
463 info->serial = !!(infobits[7] & ROW25_COLUMN7_SERIAL_MODE);
464 info->notfound = !!(infobits[8] & ROW25_COLUMN8_PAGE_NOT_FOUND);
465 info->pblf = !!(infobits[9] & ROW25_COLUMN9_PAGE_BEING_LOOKED_FOR);
467 for (column = 0; column <= 7; column++) {
468 if (infobits[column] & ROW25_COLUMN0_TO_7_HAMMING_ERROR) {
473 if (!info->hamming && !info->notfound)
474 t->is_searching[dau_no] = FALSE;
478 /* Reads 1 videotext page buffer of the SAA5246A.
480 * req is used both as input and as output. It contains information which part
481 * must be read. The videotext page is copied into req->buffer.
483 * Return value: 0 if successful
485 static inline int saa5246a_get_page(struct saa5246a_device *t,
488 int start, end, size;
492 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS ||
493 req->start < 0 || req->start > req->end || req->end >= VTX_PAGESIZE)
496 buf = kmalloc(VTX_PAGESIZE, GFP_KERNEL);
500 /* Read "normal" part of page */
503 end = min(req->end, VTX_PAGESIZE - 1);
504 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
505 req->pgbuf | R8_DO_NOT_CLEAR_MEMORY,
506 ROW(req->start), COLUMN(req->start), COMMAND_END))
508 if (i2c_getdata(t, end - req->start + 1, buf))
511 if (copy_to_user(req->buffer, buf, end - req->start + 1))
514 /* Always get the time from buffer 4, since this stupid SAA5246A only
515 * updates the currently displayed buffer...
517 if (REQ_CONTAINS_TIME(req)) {
518 start = max(req->start, POS_TIME_START);
519 end = min(req->end, POS_TIME_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, size, buf))
532 if (copy_to_user(req->buffer + start - req->start, buf, size))
535 /* Insert the header from buffer 4 only, if acquisition circuit is still searching for a page */
536 if (REQ_CONTAINS_HEADER(req) && t->is_searching[req->pgbuf]) {
537 start = max(req->start, POS_HEADER_START);
538 end = min(req->end, POS_HEADER_END);
539 size = end - start + 1;
544 if (i2c_senddata(t, SAA5246A_REGISTER_R8,
545 R8_ACTIVE_CHAPTER_4 | R8_DO_NOT_CLEAR_MEMORY,
546 R9_CURSER_ROW_0, start, COMMAND_END))
548 if (i2c_getdata(t, end - start + 1, buf))
551 if (copy_to_user(req->buffer + start - req->start, buf, size))
560 /* Stops the acquisition circuit given in dau_no. The page buffer associated
561 * with this acquisition circuit will no more be updated. The other daus are
564 * Return value: 0 if successful
566 static inline int saa5246a_stop_dau(struct saa5246a_device *t,
567 unsigned char dau_no)
569 if (dau_no >= NUM_DAUS)
571 if (i2c_senddata(t, SAA5246A_REGISTER_R2,
573 R2_IN_R3_SELECT_PAGE_HUNDREDS |
576 R2_HAMMING_CHECK_OFF,
580 R3_PAGE_HUNDREDS_DO_NOT_CARE,
586 t->is_searching[dau_no] = FALSE;
590 /* Handles ioctls defined in videotext.h
592 * Returns 0 if successful
594 static int do_saa5246a_ioctl(struct inode *inode, struct file *file,
595 unsigned int cmd, void *arg)
597 struct video_device *vd = video_devdata(file);
598 struct saa5246a_device *t=vd->priv;
603 vtx_info_t *info = arg;
605 info->version_major = MAJOR_VERSION;
606 info->version_minor = MINOR_VERSION;
607 info->numpages = NUM_DAUS;
613 vtx_pagereq_t *req = arg;
615 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
617 memset(t->pgbuf[req->pgbuf], ' ', sizeof(t->pgbuf[0]));
623 vtx_pagereq_t *req = arg;
625 if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
627 return(saa5246a_clear_found_bit(t, req->pgbuf));
632 vtx_pagereq_t *req = arg;
634 return(saa5246a_request_page(t, req));
639 vtx_pagereq_t *req = arg;
643 if ((rval = saa5246a_get_status(t, &info, req->pgbuf)))
645 if(copy_to_user(req->buffer, &info,
646 sizeof(vtx_pageinfo_t)))
653 vtx_pagereq_t *req = arg;
655 return(saa5246a_get_page(t, req));
660 vtx_pagereq_t *req = arg;
662 return(saa5246a_stop_dau(t, req->pgbuf));
677 /* I do not know what "virtual mode" means */
685 * Translates old vtx IOCTLs to new ones
687 * This keeps new kernel versions compatible with old userspace programs.
689 static inline unsigned int vtx_fix_command(unsigned int cmd)
692 case VTXIOCGETINFO_OLD:
695 case VTXIOCCLRPAGE_OLD:
698 case VTXIOCCLRFOUND_OLD:
699 cmd = VTXIOCCLRFOUND;
701 case VTXIOCPAGEREQ_OLD:
704 case VTXIOCGETSTAT_OLD:
707 case VTXIOCGETPAGE_OLD:
710 case VTXIOCSTOPDAU_OLD:
713 case VTXIOCPUTPAGE_OLD:
716 case VTXIOCSETDISP_OLD:
719 case VTXIOCPUTSTAT_OLD:
722 case VTXIOCCLRCACHE_OLD:
723 cmd = VTXIOCCLRCACHE;
725 case VTXIOCSETVIRT_OLD:
735 static int saa5246a_ioctl(struct inode *inode, struct file *file,
736 unsigned int cmd, unsigned long arg)
738 struct video_device *vd = video_devdata(file);
739 struct saa5246a_device *t = vd->priv;
742 cmd = vtx_fix_command(cmd);
744 err = video_usercopy(inode, file, cmd, arg, do_saa5246a_ioctl);
749 static int saa5246a_open(struct inode *inode, struct file *file)
751 struct video_device *vd = video_devdata(file);
752 struct saa5246a_device *t = vd->priv;
755 err = video_exclusive_open(inode,file);
759 if (t->client==NULL) {
764 if (i2c_senddata(t, SAA5246A_REGISTER_R0,
767 R0_PLL_TIME_CONSTANT_LONG |
768 R0_ENABLE_nODD_EVEN_OUTPUT |
770 R0_DO_NOT_FORCE_nODD_EVEN_LOW_IF_PICTURE_DISPLAYED |
772 R0_NO_AUTOMATIC_FASTEXT_PROMPT,
774 R1_NON_INTERLACED_312_312_LINES |
776 R1_EXTENDED_PACKET_DISABLE |
778 R1_8_BITS_NO_PARITY |
782 i2c_senddata(t, SAA5246A_REGISTER_R4,
784 /* We do not care much for the TV display but nevertheless we
785 * need the currently displayed page later because only on that
786 * page the time is updated. */
798 video_exclusive_release(inode,file);
802 static int saa5246a_release(struct inode *inode, struct file *file)
804 struct video_device *vd = video_devdata(file);
805 struct saa5246a_device *t = vd->priv;
807 /* Stop all acquisition circuits. */
808 i2c_senddata(t, SAA5246A_REGISTER_R1,
810 R1_INTERLACED_312_AND_HALF_312_AND_HALF_LINES |
812 R1_EXTENDED_PACKET_DISABLE |
814 R1_8_BITS_NO_PARITY |
818 video_exclusive_release(inode,file);
822 static int __init init_saa_5246a (void)
825 "SAA5246A (or compatible) Teletext decoder driver version %d.%d\n",
826 MAJOR_VERSION, MINOR_VERSION);
827 return i2c_add_driver(&i2c_driver_videotext);
830 static void __exit cleanup_saa_5246a (void)
832 i2c_del_driver(&i2c_driver_videotext);
835 module_init(init_saa_5246a);
836 module_exit(cleanup_saa_5246a);
838 static struct file_operations saa_fops = {
839 .owner = THIS_MODULE,
840 .open = saa5246a_open,
841 .release = saa5246a_release,
842 .ioctl = saa5246a_ioctl,
846 static struct video_device saa_template =
848 .owner = THIS_MODULE,
850 .type = VID_TYPE_TELETEXT,
851 .hardware = VID_HARDWARE_SAA5249,
853 .release = video_device_release,