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>
44 #include <linux/init.h>
45 #include <linux/i2c.h>
46 #include <linux/videotext.h>
47 #include <linux/videodev.h>
48 #include <media/v4l2-common.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
};
72 static struct i2c_client client_template
;
74 static int saa5246a_attach(struct i2c_adapter
*adap
, int addr
, int kind
)
78 struct i2c_client
*client
;
79 struct video_device
*vd
;
80 struct saa5246a_device
*t
;
82 printk(KERN_INFO
"saa5246a: teletext chip found.\n");
83 client
=kmalloc(sizeof(*client
), GFP_KERNEL
);
86 client_template
.adapter
= adap
;
87 client_template
.addr
= addr
;
88 memcpy(client
, &client_template
, sizeof(*client
));
89 t
= kzalloc(sizeof(*t
), GFP_KERNEL
);
95 strlcpy(client
->name
, IF_NAME
, I2C_NAME_SIZE
);
99 * Now create a video4linux device
102 vd
= video_device_alloc();
109 i2c_set_clientdata(client
, vd
);
110 memcpy(vd
, &saa_template
, sizeof(*vd
));
112 for (pgbuf
= 0; pgbuf
< NUM_DAUS
; pgbuf
++)
114 memset(t
->pgbuf
[pgbuf
], ' ', sizeof(t
->pgbuf
[0]));
115 t
->is_searching
[pgbuf
] = false;
124 if((err
=video_register_device(vd
, VFL_TYPE_VTX
,-1))<0)
128 video_device_release(vd
);
132 i2c_attach_client(client
);
137 * We do most of the hard work when we become a device on the i2c.
139 static int saa5246a_probe(struct i2c_adapter
*adap
)
141 if (adap
->class & I2C_CLASS_TV_ANALOG
)
142 return i2c_probe(adap
, &addr_data
, saa5246a_attach
);
146 static int saa5246a_detach(struct i2c_client
*client
)
148 struct video_device
*vd
= i2c_get_clientdata(client
);
149 i2c_detach_client(client
);
150 video_unregister_device(vd
);
160 static struct i2c_driver i2c_driver_videotext
=
163 .name
= IF_NAME
, /* name */
165 .id
= I2C_DRIVERID_SAA5249
, /* in i2c.h */
166 .attach_adapter
= saa5246a_probe
,
167 .detach_client
= saa5246a_detach
,
170 static struct i2c_client client_template
= {
171 .driver
= &i2c_driver_videotext
,
175 static int i2c_sendbuf(struct saa5246a_device
*t
, int reg
, int count
, u8
*data
)
180 memcpy(buf
+1, data
, count
);
182 if(i2c_master_send(t
->client
, buf
, count
+1)==count
+1)
187 static int i2c_senddata(struct saa5246a_device
*t
, ...)
189 unsigned char buf
[64];
195 while ((v
= va_arg(argp
, int)) != -1)
199 return i2c_sendbuf(t
, buf
[0], ct
-1, buf
+1);
202 /* Get count number of bytes from I²C-device at address adr, store them in buf.
203 * Start & stop handshaking is done by this routine, ack will be sent after the
204 * last byte to inhibit further sending of data. If uaccess is 'true', data is
205 * written to user-space with put_user. Returns -1 if I²C-device didn't send
206 * acknowledge, 0 otherwise
208 static int i2c_getdata(struct saa5246a_device
*t
, int count
, u8
*buf
)
210 if(i2c_master_recv(t
->client
, buf
, count
)!=count
)
215 /* When a page is found then the not FOUND bit in one of the status registers
216 * of the SAA5264A chip is cleared. Unfortunately this bit is not set
217 * automatically when a new page is requested. Instead this function must be
218 * called after a page has been requested.
220 * Return value: 0 if successful
222 static int saa5246a_clear_found_bit(struct saa5246a_device
*t
,
223 unsigned char dau_no
)
225 unsigned char row_25_column_8
;
227 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
230 R8_DO_NOT_CLEAR_MEMORY
,
237 i2c_getdata(t
, 1, &row_25_column_8
))
241 row_25_column_8
|= ROW25_COLUMN8_PAGE_NOT_FOUND
;
242 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
245 R8_DO_NOT_CLEAR_MEMORY
,
261 /* Requests one videotext page as described in req. The fields of req are
262 * checked and an error is returned if something is invalid.
264 * Return value: 0 if successful
266 static int saa5246a_request_page(struct saa5246a_device
*t
,
269 if (req
->pagemask
< 0 || req
->pagemask
>= PGMASK_MAX
)
271 if (req
->pagemask
& PGMASK_PAGE
)
272 if (req
->page
< 0 || req
->page
> PAGE_MAX
)
274 if (req
->pagemask
& PGMASK_HOUR
)
275 if (req
->hour
< 0 || req
->hour
> HOUR_MAX
)
277 if (req
->pagemask
& PGMASK_MINUTE
)
278 if (req
->minute
< 0 || req
->minute
> MINUTE_MAX
)
280 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
)
283 if (i2c_senddata(t
, SAA5246A_REGISTER_R2
,
285 R2_IN_R3_SELECT_PAGE_HUNDREDS
|
288 R2_HAMMING_CHECK_OFF
,
290 HUNDREDS_OF_PAGE(req
->page
) |
292 (req
->pagemask
& PG_HUND
?
293 R3_PAGE_HUNDREDS_DO_CARE
:
294 R3_PAGE_HUNDREDS_DO_NOT_CARE
),
296 TENS_OF_PAGE(req
->page
) |
297 (req
->pagemask
& PG_TEN
?
298 R3_PAGE_TENS_DO_CARE
:
299 R3_PAGE_TENS_DO_NOT_CARE
),
301 UNITS_OF_PAGE(req
->page
) |
302 (req
->pagemask
& PG_UNIT
?
303 R3_PAGE_UNITS_DO_CARE
:
304 R3_PAGE_UNITS_DO_NOT_CARE
),
306 TENS_OF_HOUR(req
->hour
) |
307 (req
->pagemask
& HR_TEN
?
308 R3_HOURS_TENS_DO_CARE
:
309 R3_HOURS_TENS_DO_NOT_CARE
),
311 UNITS_OF_HOUR(req
->hour
) |
312 (req
->pagemask
& HR_UNIT
?
313 R3_HOURS_UNITS_DO_CARE
:
314 R3_HOURS_UNITS_DO_NOT_CARE
),
316 TENS_OF_MINUTE(req
->minute
) |
317 (req
->pagemask
& MIN_TEN
?
318 R3_MINUTES_TENS_DO_CARE
:
319 R3_MINUTES_TENS_DO_NOT_CARE
),
321 UNITS_OF_MINUTE(req
->minute
) |
322 (req
->pagemask
& MIN_UNIT
?
323 R3_MINUTES_UNITS_DO_CARE
:
324 R3_MINUTES_UNITS_DO_NOT_CARE
),
326 COMMAND_END
) || i2c_senddata(t
, SAA5246A_REGISTER_R2
,
328 R2_IN_R3_SELECT_PAGE_HUNDREDS
|
331 R2_HAMMING_CHECK_OFF
,
333 HUNDREDS_OF_PAGE(req
->page
) |
335 (req
->pagemask
& PG_HUND
?
336 R3_PAGE_HUNDREDS_DO_CARE
:
337 R3_PAGE_HUNDREDS_DO_NOT_CARE
),
344 t
->is_searching
[req
->pgbuf
] = true;
348 /* This routine decodes the page number from the infobits contained in line 25.
351 * infobits: must be bits 0 to 9 of column 25
353 * Return value: page number coded in hexadecimal, i. e. page 123 is coded 0x123
355 static inline int saa5246a_extract_pagenum_from_infobits(
356 unsigned char infobits
[10])
358 int page_hundreds
, page_tens
, page_units
;
360 page_units
= infobits
[0] & ROW25_COLUMN0_PAGE_UNITS
;
361 page_tens
= infobits
[1] & ROW25_COLUMN1_PAGE_TENS
;
362 page_hundreds
= infobits
[8] & ROW25_COLUMN8_PAGE_HUNDREDS
;
364 /* page 0x.. means page 8.. */
365 if (page_hundreds
== 0)
368 return((page_hundreds
<< 8) | (page_tens
<< 4) | page_units
);
371 /* Decodes the hour from the infobits contained in line 25.
374 * infobits: must be bits 0 to 9 of column 25
376 * Return: hour coded in hexadecimal, i. e. 12h is coded 0x12
378 static inline int saa5246a_extract_hour_from_infobits(
379 unsigned char infobits
[10])
381 int hour_tens
, hour_units
;
383 hour_units
= infobits
[4] & ROW25_COLUMN4_HOUR_UNITS
;
384 hour_tens
= infobits
[5] & ROW25_COLUMN5_HOUR_TENS
;
386 return((hour_tens
<< 4) | hour_units
);
389 /* Decodes the minutes from the infobits contained in line 25.
392 * infobits: must be bits 0 to 9 of column 25
394 * Return: minutes coded in hexadecimal, i. e. 10min is coded 0x10
396 static inline int saa5246a_extract_minutes_from_infobits(
397 unsigned char infobits
[10])
399 int minutes_tens
, minutes_units
;
401 minutes_units
= infobits
[2] & ROW25_COLUMN2_MINUTES_UNITS
;
402 minutes_tens
= infobits
[3] & ROW25_COLUMN3_MINUTES_TENS
;
404 return((minutes_tens
<< 4) | minutes_units
);
407 /* Reads the status bits contained in the first 10 columns of the first line
408 * and extracts the information into info.
410 * Return value: 0 if successful
412 static inline int saa5246a_get_status(struct saa5246a_device
*t
,
413 vtx_pageinfo_t
*info
, unsigned char dau_no
)
415 unsigned char infobits
[10];
418 if (dau_no
>= NUM_DAUS
)
421 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
424 R8_DO_NOT_CLEAR_MEMORY
,
431 i2c_getdata(t
, 10, infobits
))
436 info
->pagenum
= saa5246a_extract_pagenum_from_infobits(infobits
);
437 info
->hour
= saa5246a_extract_hour_from_infobits(infobits
);
438 info
->minute
= saa5246a_extract_minutes_from_infobits(infobits
);
439 info
->charset
= ((infobits
[7] & ROW25_COLUMN7_CHARACTER_SET
) >> 1);
440 info
->delete = !!(infobits
[3] & ROW25_COLUMN3_DELETE_PAGE
);
441 info
->headline
= !!(infobits
[5] & ROW25_COLUMN5_INSERT_HEADLINE
);
442 info
->subtitle
= !!(infobits
[5] & ROW25_COLUMN5_INSERT_SUBTITLE
);
443 info
->supp_header
= !!(infobits
[6] & ROW25_COLUMN6_SUPPRESS_HEADER
);
444 info
->update
= !!(infobits
[6] & ROW25_COLUMN6_UPDATE_PAGE
);
445 info
->inter_seq
= !!(infobits
[6] & ROW25_COLUMN6_INTERRUPTED_SEQUENCE
);
446 info
->dis_disp
= !!(infobits
[6] & ROW25_COLUMN6_SUPPRESS_DISPLAY
);
447 info
->serial
= !!(infobits
[7] & ROW25_COLUMN7_SERIAL_MODE
);
448 info
->notfound
= !!(infobits
[8] & ROW25_COLUMN8_PAGE_NOT_FOUND
);
449 info
->pblf
= !!(infobits
[9] & ROW25_COLUMN9_PAGE_BEING_LOOKED_FOR
);
451 for (column
= 0; column
<= 7; column
++) {
452 if (infobits
[column
] & ROW25_COLUMN0_TO_7_HAMMING_ERROR
) {
457 if (!info
->hamming
&& !info
->notfound
)
458 t
->is_searching
[dau_no
] = false;
462 /* Reads 1 videotext page buffer of the SAA5246A.
464 * req is used both as input and as output. It contains information which part
465 * must be read. The videotext page is copied into req->buffer.
467 * Return value: 0 if successful
469 static inline int saa5246a_get_page(struct saa5246a_device
*t
,
472 int start
, end
, size
;
476 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
||
477 req
->start
< 0 || req
->start
> req
->end
|| req
->end
>= VTX_PAGESIZE
)
480 buf
= kmalloc(VTX_PAGESIZE
, GFP_KERNEL
);
484 /* Read "normal" part of page */
487 end
= min(req
->end
, VTX_PAGESIZE
- 1);
488 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
489 req
->pgbuf
| R8_DO_NOT_CLEAR_MEMORY
,
490 ROW(req
->start
), COLUMN(req
->start
), COMMAND_END
))
492 if (i2c_getdata(t
, end
- req
->start
+ 1, buf
))
495 if (copy_to_user(req
->buffer
, buf
, end
- req
->start
+ 1))
498 /* Always get the time from buffer 4, since this stupid SAA5246A only
499 * updates the currently displayed buffer...
501 if (REQ_CONTAINS_TIME(req
)) {
502 start
= max(req
->start
, POS_TIME_START
);
503 end
= min(req
->end
, POS_TIME_END
);
504 size
= end
- start
+ 1;
509 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
510 R8_ACTIVE_CHAPTER_4
| R8_DO_NOT_CLEAR_MEMORY
,
511 R9_CURSER_ROW_0
, start
, COMMAND_END
))
513 if (i2c_getdata(t
, size
, buf
))
516 if (copy_to_user(req
->buffer
+ start
- req
->start
, buf
, size
))
519 /* Insert the header from buffer 4 only, if acquisition circuit is still searching for a page */
520 if (REQ_CONTAINS_HEADER(req
) && t
->is_searching
[req
->pgbuf
]) {
521 start
= max(req
->start
, POS_HEADER_START
);
522 end
= min(req
->end
, POS_HEADER_END
);
523 size
= end
- start
+ 1;
528 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
529 R8_ACTIVE_CHAPTER_4
| R8_DO_NOT_CLEAR_MEMORY
,
530 R9_CURSER_ROW_0
, start
, COMMAND_END
))
532 if (i2c_getdata(t
, end
- start
+ 1, buf
))
535 if (copy_to_user(req
->buffer
+ start
- req
->start
, buf
, size
))
544 /* Stops the acquisition circuit given in dau_no. The page buffer associated
545 * with this acquisition circuit will no more be updated. The other daus are
548 * Return value: 0 if successful
550 static inline int saa5246a_stop_dau(struct saa5246a_device
*t
,
551 unsigned char dau_no
)
553 if (dau_no
>= NUM_DAUS
)
555 if (i2c_senddata(t
, SAA5246A_REGISTER_R2
,
557 R2_IN_R3_SELECT_PAGE_HUNDREDS
|
560 R2_HAMMING_CHECK_OFF
,
564 R3_PAGE_HUNDREDS_DO_NOT_CARE
,
570 t
->is_searching
[dau_no
] = false;
574 /* Handles ioctls defined in videotext.h
576 * Returns 0 if successful
578 static int do_saa5246a_ioctl(struct inode
*inode
, struct file
*file
,
579 unsigned int cmd
, void *arg
)
581 struct video_device
*vd
= video_devdata(file
);
582 struct saa5246a_device
*t
=vd
->priv
;
587 vtx_info_t
*info
= arg
;
589 info
->version_major
= MAJOR_VERSION
;
590 info
->version_minor
= MINOR_VERSION
;
591 info
->numpages
= NUM_DAUS
;
597 vtx_pagereq_t
*req
= arg
;
599 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
)
601 memset(t
->pgbuf
[req
->pgbuf
], ' ', sizeof(t
->pgbuf
[0]));
607 vtx_pagereq_t
*req
= arg
;
609 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
)
611 return(saa5246a_clear_found_bit(t
, req
->pgbuf
));
616 vtx_pagereq_t
*req
= arg
;
618 return(saa5246a_request_page(t
, req
));
623 vtx_pagereq_t
*req
= arg
;
627 if ((rval
= saa5246a_get_status(t
, &info
, req
->pgbuf
)))
629 if(copy_to_user(req
->buffer
, &info
,
630 sizeof(vtx_pageinfo_t
)))
637 vtx_pagereq_t
*req
= arg
;
639 return(saa5246a_get_page(t
, req
));
644 vtx_pagereq_t
*req
= arg
;
646 return(saa5246a_stop_dau(t
, req
->pgbuf
));
661 /* I do not know what "virtual mode" means */
669 * Translates old vtx IOCTLs to new ones
671 * This keeps new kernel versions compatible with old userspace programs.
673 static inline unsigned int vtx_fix_command(unsigned int cmd
)
676 case VTXIOCGETINFO_OLD
:
679 case VTXIOCCLRPAGE_OLD
:
682 case VTXIOCCLRFOUND_OLD
:
683 cmd
= VTXIOCCLRFOUND
;
685 case VTXIOCPAGEREQ_OLD
:
688 case VTXIOCGETSTAT_OLD
:
691 case VTXIOCGETPAGE_OLD
:
694 case VTXIOCSTOPDAU_OLD
:
697 case VTXIOCPUTPAGE_OLD
:
700 case VTXIOCSETDISP_OLD
:
703 case VTXIOCPUTSTAT_OLD
:
706 case VTXIOCCLRCACHE_OLD
:
707 cmd
= VTXIOCCLRCACHE
;
709 case VTXIOCSETVIRT_OLD
:
719 static int saa5246a_ioctl(struct inode
*inode
, struct file
*file
,
720 unsigned int cmd
, unsigned long arg
)
722 struct video_device
*vd
= video_devdata(file
);
723 struct saa5246a_device
*t
= vd
->priv
;
726 cmd
= vtx_fix_command(cmd
);
727 mutex_lock(&t
->lock
);
728 err
= video_usercopy(inode
, file
, cmd
, arg
, do_saa5246a_ioctl
);
729 mutex_unlock(&t
->lock
);
733 static int saa5246a_open(struct inode
*inode
, struct file
*file
)
735 struct video_device
*vd
= video_devdata(file
);
736 struct saa5246a_device
*t
= vd
->priv
;
739 err
= video_exclusive_open(inode
,file
);
743 if (t
->client
==NULL
) {
748 if (i2c_senddata(t
, SAA5246A_REGISTER_R0
,
751 R0_PLL_TIME_CONSTANT_LONG
|
752 R0_ENABLE_nODD_EVEN_OUTPUT
|
754 R0_DO_NOT_FORCE_nODD_EVEN_LOW_IF_PICTURE_DISPLAYED
|
756 R0_NO_AUTOMATIC_FASTEXT_PROMPT
,
758 R1_NON_INTERLACED_312_312_LINES
|
760 R1_EXTENDED_PACKET_DISABLE
|
762 R1_8_BITS_NO_PARITY
|
766 i2c_senddata(t
, SAA5246A_REGISTER_R4
,
768 /* We do not care much for the TV display but nevertheless we
769 * need the currently displayed page later because only on that
770 * page the time is updated. */
782 video_exclusive_release(inode
,file
);
786 static int saa5246a_release(struct inode
*inode
, struct file
*file
)
788 struct video_device
*vd
= video_devdata(file
);
789 struct saa5246a_device
*t
= vd
->priv
;
791 /* Stop all acquisition circuits. */
792 i2c_senddata(t
, SAA5246A_REGISTER_R1
,
794 R1_INTERLACED_312_AND_HALF_312_AND_HALF_LINES
|
796 R1_EXTENDED_PACKET_DISABLE
|
798 R1_8_BITS_NO_PARITY
|
802 video_exclusive_release(inode
,file
);
806 static int __init
init_saa_5246a (void)
809 "SAA5246A (or compatible) Teletext decoder driver version %d.%d\n",
810 MAJOR_VERSION
, MINOR_VERSION
);
811 return i2c_add_driver(&i2c_driver_videotext
);
814 static void __exit
cleanup_saa_5246a (void)
816 i2c_del_driver(&i2c_driver_videotext
);
819 module_init(init_saa_5246a
);
820 module_exit(cleanup_saa_5246a
);
822 static const struct file_operations saa_fops
= {
823 .owner
= THIS_MODULE
,
824 .open
= saa5246a_open
,
825 .release
= saa5246a_release
,
826 .ioctl
= saa5246a_ioctl
,
830 static struct video_device saa_template
=
832 .owner
= THIS_MODULE
,
834 .type
= VID_TYPE_TELETEXT
,
836 .release
= video_device_release
,