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 <media/v4l2-common.h>
50 #include <linux/mutex.h>
54 MODULE_AUTHOR("Michael Geng <linux@MichaelGeng.de>");
55 MODULE_DESCRIPTION("Philips SAA5246A, SAA5281 Teletext decoder driver");
56 MODULE_LICENSE("GPL");
58 struct saa5246a_device
60 u8 pgbuf
[NUM_DAUS
][VTX_VIRTUALSIZE
];
61 int is_searching
[NUM_DAUS
];
62 struct i2c_client
*client
;
66 static struct video_device saa_template
; /* Declared near bottom */
68 /* Addresses to scan */
69 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)
197 return i2c_sendbuf(t
, buf
[0], ct
-1, buf
+1);
200 /* Get count number of bytes from I²C-device at address adr, store them in buf.
201 * Start & stop handshaking is done by this routine, ack will be sent after the
202 * last byte to inhibit further sending of data. If uaccess is TRUE, data is
203 * written to user-space with put_user. Returns -1 if I²C-device didn't send
204 * acknowledge, 0 otherwise
206 static int i2c_getdata(struct saa5246a_device
*t
, int count
, u8
*buf
)
208 if(i2c_master_recv(t
->client
, buf
, count
)!=count
)
213 /* When a page is found then the not FOUND bit in one of the status registers
214 * of the SAA5264A chip is cleared. Unfortunately this bit is not set
215 * automatically when a new page is requested. Instead this function must be
216 * called after a page has been requested.
218 * Return value: 0 if successful
220 static int saa5246a_clear_found_bit(struct saa5246a_device
*t
,
221 unsigned char dau_no
)
223 unsigned char row_25_column_8
;
225 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
228 R8_DO_NOT_CLEAR_MEMORY
,
235 i2c_getdata(t
, 1, &row_25_column_8
))
239 row_25_column_8
|= ROW25_COLUMN8_PAGE_NOT_FOUND
;
240 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
243 R8_DO_NOT_CLEAR_MEMORY
,
259 /* Requests one videotext page as described in req. The fields of req are
260 * checked and an error is returned if something is invalid.
262 * Return value: 0 if successful
264 static int saa5246a_request_page(struct saa5246a_device
*t
,
267 if (req
->pagemask
< 0 || req
->pagemask
>= PGMASK_MAX
)
269 if (req
->pagemask
& PGMASK_PAGE
)
270 if (req
->page
< 0 || req
->page
> PAGE_MAX
)
272 if (req
->pagemask
& PGMASK_HOUR
)
273 if (req
->hour
< 0 || req
->hour
> HOUR_MAX
)
275 if (req
->pagemask
& PGMASK_MINUTE
)
276 if (req
->minute
< 0 || req
->minute
> MINUTE_MAX
)
278 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
)
281 if (i2c_senddata(t
, SAA5246A_REGISTER_R2
,
283 R2_IN_R3_SELECT_PAGE_HUNDREDS
|
286 R2_HAMMING_CHECK_OFF
,
288 HUNDREDS_OF_PAGE(req
->page
) |
290 (req
->pagemask
& PG_HUND
?
291 R3_PAGE_HUNDREDS_DO_CARE
:
292 R3_PAGE_HUNDREDS_DO_NOT_CARE
),
294 TENS_OF_PAGE(req
->page
) |
295 (req
->pagemask
& PG_TEN
?
296 R3_PAGE_TENS_DO_CARE
:
297 R3_PAGE_TENS_DO_NOT_CARE
),
299 UNITS_OF_PAGE(req
->page
) |
300 (req
->pagemask
& PG_UNIT
?
301 R3_PAGE_UNITS_DO_CARE
:
302 R3_PAGE_UNITS_DO_NOT_CARE
),
304 TENS_OF_HOUR(req
->hour
) |
305 (req
->pagemask
& HR_TEN
?
306 R3_HOURS_TENS_DO_CARE
:
307 R3_HOURS_TENS_DO_NOT_CARE
),
309 UNITS_OF_HOUR(req
->hour
) |
310 (req
->pagemask
& HR_UNIT
?
311 R3_HOURS_UNITS_DO_CARE
:
312 R3_HOURS_UNITS_DO_NOT_CARE
),
314 TENS_OF_MINUTE(req
->minute
) |
315 (req
->pagemask
& MIN_TEN
?
316 R3_MINUTES_TENS_DO_CARE
:
317 R3_MINUTES_TENS_DO_NOT_CARE
),
319 UNITS_OF_MINUTE(req
->minute
) |
320 (req
->pagemask
& MIN_UNIT
?
321 R3_MINUTES_UNITS_DO_CARE
:
322 R3_MINUTES_UNITS_DO_NOT_CARE
),
324 COMMAND_END
) || i2c_senddata(t
, SAA5246A_REGISTER_R2
,
326 R2_IN_R3_SELECT_PAGE_HUNDREDS
|
329 R2_HAMMING_CHECK_OFF
,
331 HUNDREDS_OF_PAGE(req
->page
) |
333 (req
->pagemask
& PG_HUND
?
334 R3_PAGE_HUNDREDS_DO_CARE
:
335 R3_PAGE_HUNDREDS_DO_NOT_CARE
),
342 t
->is_searching
[req
->pgbuf
] = TRUE
;
346 /* This routine decodes the page number from the infobits contained in line 25.
349 * infobits: must be bits 0 to 9 of column 25
351 * Return value: page number coded in hexadecimal, i. e. page 123 is coded 0x123
353 static inline int saa5246a_extract_pagenum_from_infobits(
354 unsigned char infobits
[10])
356 int page_hundreds
, page_tens
, page_units
;
358 page_units
= infobits
[0] & ROW25_COLUMN0_PAGE_UNITS
;
359 page_tens
= infobits
[1] & ROW25_COLUMN1_PAGE_TENS
;
360 page_hundreds
= infobits
[8] & ROW25_COLUMN8_PAGE_HUNDREDS
;
362 /* page 0x.. means page 8.. */
363 if (page_hundreds
== 0)
366 return((page_hundreds
<< 8) | (page_tens
<< 4) | page_units
);
369 /* Decodes the hour from the infobits contained in line 25.
372 * infobits: must be bits 0 to 9 of column 25
374 * Return: hour coded in hexadecimal, i. e. 12h is coded 0x12
376 static inline int saa5246a_extract_hour_from_infobits(
377 unsigned char infobits
[10])
379 int hour_tens
, hour_units
;
381 hour_units
= infobits
[4] & ROW25_COLUMN4_HOUR_UNITS
;
382 hour_tens
= infobits
[5] & ROW25_COLUMN5_HOUR_TENS
;
384 return((hour_tens
<< 4) | hour_units
);
387 /* Decodes the minutes from the infobits contained in line 25.
390 * infobits: must be bits 0 to 9 of column 25
392 * Return: minutes coded in hexadecimal, i. e. 10min is coded 0x10
394 static inline int saa5246a_extract_minutes_from_infobits(
395 unsigned char infobits
[10])
397 int minutes_tens
, minutes_units
;
399 minutes_units
= infobits
[2] & ROW25_COLUMN2_MINUTES_UNITS
;
400 minutes_tens
= infobits
[3] & ROW25_COLUMN3_MINUTES_TENS
;
402 return((minutes_tens
<< 4) | minutes_units
);
405 /* Reads the status bits contained in the first 10 columns of the first line
406 * and extracts the information into info.
408 * Return value: 0 if successful
410 static inline int saa5246a_get_status(struct saa5246a_device
*t
,
411 vtx_pageinfo_t
*info
, unsigned char dau_no
)
413 unsigned char infobits
[10];
416 if (dau_no
>= NUM_DAUS
)
419 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
422 R8_DO_NOT_CLEAR_MEMORY
,
429 i2c_getdata(t
, 10, infobits
))
434 info
->pagenum
= saa5246a_extract_pagenum_from_infobits(infobits
);
435 info
->hour
= saa5246a_extract_hour_from_infobits(infobits
);
436 info
->minute
= saa5246a_extract_minutes_from_infobits(infobits
);
437 info
->charset
= ((infobits
[7] & ROW25_COLUMN7_CHARACTER_SET
) >> 1);
438 info
->delete = !!(infobits
[3] & ROW25_COLUMN3_DELETE_PAGE
);
439 info
->headline
= !!(infobits
[5] & ROW25_COLUMN5_INSERT_HEADLINE
);
440 info
->subtitle
= !!(infobits
[5] & ROW25_COLUMN5_INSERT_SUBTITLE
);
441 info
->supp_header
= !!(infobits
[6] & ROW25_COLUMN6_SUPPRESS_HEADER
);
442 info
->update
= !!(infobits
[6] & ROW25_COLUMN6_UPDATE_PAGE
);
443 info
->inter_seq
= !!(infobits
[6] & ROW25_COLUMN6_INTERRUPTED_SEQUENCE
);
444 info
->dis_disp
= !!(infobits
[6] & ROW25_COLUMN6_SUPPRESS_DISPLAY
);
445 info
->serial
= !!(infobits
[7] & ROW25_COLUMN7_SERIAL_MODE
);
446 info
->notfound
= !!(infobits
[8] & ROW25_COLUMN8_PAGE_NOT_FOUND
);
447 info
->pblf
= !!(infobits
[9] & ROW25_COLUMN9_PAGE_BEING_LOOKED_FOR
);
449 for (column
= 0; column
<= 7; column
++) {
450 if (infobits
[column
] & ROW25_COLUMN0_TO_7_HAMMING_ERROR
) {
455 if (!info
->hamming
&& !info
->notfound
)
456 t
->is_searching
[dau_no
] = FALSE
;
460 /* Reads 1 videotext page buffer of the SAA5246A.
462 * req is used both as input and as output. It contains information which part
463 * must be read. The videotext page is copied into req->buffer.
465 * Return value: 0 if successful
467 static inline int saa5246a_get_page(struct saa5246a_device
*t
,
470 int start
, end
, size
;
474 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
||
475 req
->start
< 0 || req
->start
> req
->end
|| req
->end
>= VTX_PAGESIZE
)
478 buf
= kmalloc(VTX_PAGESIZE
, GFP_KERNEL
);
482 /* Read "normal" part of page */
485 end
= min(req
->end
, VTX_PAGESIZE
- 1);
486 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
487 req
->pgbuf
| R8_DO_NOT_CLEAR_MEMORY
,
488 ROW(req
->start
), COLUMN(req
->start
), COMMAND_END
))
490 if (i2c_getdata(t
, end
- req
->start
+ 1, buf
))
493 if (copy_to_user(req
->buffer
, buf
, end
- req
->start
+ 1))
496 /* Always get the time from buffer 4, since this stupid SAA5246A only
497 * updates the currently displayed buffer...
499 if (REQ_CONTAINS_TIME(req
)) {
500 start
= max(req
->start
, POS_TIME_START
);
501 end
= min(req
->end
, POS_TIME_END
);
502 size
= end
- start
+ 1;
507 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
508 R8_ACTIVE_CHAPTER_4
| R8_DO_NOT_CLEAR_MEMORY
,
509 R9_CURSER_ROW_0
, start
, COMMAND_END
))
511 if (i2c_getdata(t
, size
, buf
))
514 if (copy_to_user(req
->buffer
+ start
- req
->start
, buf
, size
))
517 /* Insert the header from buffer 4 only, if acquisition circuit is still searching for a page */
518 if (REQ_CONTAINS_HEADER(req
) && t
->is_searching
[req
->pgbuf
]) {
519 start
= max(req
->start
, POS_HEADER_START
);
520 end
= min(req
->end
, POS_HEADER_END
);
521 size
= end
- start
+ 1;
526 if (i2c_senddata(t
, SAA5246A_REGISTER_R8
,
527 R8_ACTIVE_CHAPTER_4
| R8_DO_NOT_CLEAR_MEMORY
,
528 R9_CURSER_ROW_0
, start
, COMMAND_END
))
530 if (i2c_getdata(t
, end
- start
+ 1, buf
))
533 if (copy_to_user(req
->buffer
+ start
- req
->start
, buf
, size
))
542 /* Stops the acquisition circuit given in dau_no. The page buffer associated
543 * with this acquisition circuit will no more be updated. The other daus are
546 * Return value: 0 if successful
548 static inline int saa5246a_stop_dau(struct saa5246a_device
*t
,
549 unsigned char dau_no
)
551 if (dau_no
>= NUM_DAUS
)
553 if (i2c_senddata(t
, SAA5246A_REGISTER_R2
,
555 R2_IN_R3_SELECT_PAGE_HUNDREDS
|
558 R2_HAMMING_CHECK_OFF
,
562 R3_PAGE_HUNDREDS_DO_NOT_CARE
,
568 t
->is_searching
[dau_no
] = FALSE
;
572 /* Handles ioctls defined in videotext.h
574 * Returns 0 if successful
576 static int do_saa5246a_ioctl(struct inode
*inode
, struct file
*file
,
577 unsigned int cmd
, void *arg
)
579 struct video_device
*vd
= video_devdata(file
);
580 struct saa5246a_device
*t
=vd
->priv
;
585 vtx_info_t
*info
= arg
;
587 info
->version_major
= MAJOR_VERSION
;
588 info
->version_minor
= MINOR_VERSION
;
589 info
->numpages
= NUM_DAUS
;
595 vtx_pagereq_t
*req
= arg
;
597 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
)
599 memset(t
->pgbuf
[req
->pgbuf
], ' ', sizeof(t
->pgbuf
[0]));
605 vtx_pagereq_t
*req
= arg
;
607 if (req
->pgbuf
< 0 || req
->pgbuf
>= NUM_DAUS
)
609 return(saa5246a_clear_found_bit(t
, req
->pgbuf
));
614 vtx_pagereq_t
*req
= arg
;
616 return(saa5246a_request_page(t
, req
));
621 vtx_pagereq_t
*req
= arg
;
625 if ((rval
= saa5246a_get_status(t
, &info
, req
->pgbuf
)))
627 if(copy_to_user(req
->buffer
, &info
,
628 sizeof(vtx_pageinfo_t
)))
635 vtx_pagereq_t
*req
= arg
;
637 return(saa5246a_get_page(t
, req
));
642 vtx_pagereq_t
*req
= arg
;
644 return(saa5246a_stop_dau(t
, req
->pgbuf
));
659 /* I do not know what "virtual mode" means */
667 * Translates old vtx IOCTLs to new ones
669 * This keeps new kernel versions compatible with old userspace programs.
671 static inline unsigned int vtx_fix_command(unsigned int cmd
)
674 case VTXIOCGETINFO_OLD
:
677 case VTXIOCCLRPAGE_OLD
:
680 case VTXIOCCLRFOUND_OLD
:
681 cmd
= VTXIOCCLRFOUND
;
683 case VTXIOCPAGEREQ_OLD
:
686 case VTXIOCGETSTAT_OLD
:
689 case VTXIOCGETPAGE_OLD
:
692 case VTXIOCSTOPDAU_OLD
:
695 case VTXIOCPUTPAGE_OLD
:
698 case VTXIOCSETDISP_OLD
:
701 case VTXIOCPUTSTAT_OLD
:
704 case VTXIOCCLRCACHE_OLD
:
705 cmd
= VTXIOCCLRCACHE
;
707 case VTXIOCSETVIRT_OLD
:
717 static int saa5246a_ioctl(struct inode
*inode
, struct file
*file
,
718 unsigned int cmd
, unsigned long arg
)
720 struct video_device
*vd
= video_devdata(file
);
721 struct saa5246a_device
*t
= vd
->priv
;
724 cmd
= vtx_fix_command(cmd
);
725 mutex_lock(&t
->lock
);
726 err
= video_usercopy(inode
, file
, cmd
, arg
, do_saa5246a_ioctl
);
727 mutex_unlock(&t
->lock
);
731 static int saa5246a_open(struct inode
*inode
, struct file
*file
)
733 struct video_device
*vd
= video_devdata(file
);
734 struct saa5246a_device
*t
= vd
->priv
;
737 err
= video_exclusive_open(inode
,file
);
741 if (t
->client
==NULL
) {
746 if (i2c_senddata(t
, SAA5246A_REGISTER_R0
,
749 R0_PLL_TIME_CONSTANT_LONG
|
750 R0_ENABLE_nODD_EVEN_OUTPUT
|
752 R0_DO_NOT_FORCE_nODD_EVEN_LOW_IF_PICTURE_DISPLAYED
|
754 R0_NO_AUTOMATIC_FASTEXT_PROMPT
,
756 R1_NON_INTERLACED_312_312_LINES
|
758 R1_EXTENDED_PACKET_DISABLE
|
760 R1_8_BITS_NO_PARITY
|
764 i2c_senddata(t
, SAA5246A_REGISTER_R4
,
766 /* We do not care much for the TV display but nevertheless we
767 * need the currently displayed page later because only on that
768 * page the time is updated. */
780 video_exclusive_release(inode
,file
);
784 static int saa5246a_release(struct inode
*inode
, struct file
*file
)
786 struct video_device
*vd
= video_devdata(file
);
787 struct saa5246a_device
*t
= vd
->priv
;
789 /* Stop all acquisition circuits. */
790 i2c_senddata(t
, SAA5246A_REGISTER_R1
,
792 R1_INTERLACED_312_AND_HALF_312_AND_HALF_LINES
|
794 R1_EXTENDED_PACKET_DISABLE
|
796 R1_8_BITS_NO_PARITY
|
800 video_exclusive_release(inode
,file
);
804 static int __init
init_saa_5246a (void)
807 "SAA5246A (or compatible) Teletext decoder driver version %d.%d\n",
808 MAJOR_VERSION
, MINOR_VERSION
);
809 return i2c_add_driver(&i2c_driver_videotext
);
812 static void __exit
cleanup_saa_5246a (void)
814 i2c_del_driver(&i2c_driver_videotext
);
817 module_init(init_saa_5246a
);
818 module_exit(cleanup_saa_5246a
);
820 static const struct file_operations saa_fops
= {
821 .owner
= THIS_MODULE
,
822 .open
= saa5246a_open
,
823 .release
= saa5246a_release
,
824 .ioctl
= saa5246a_ioctl
,
828 static struct video_device saa_template
=
830 .owner
= THIS_MODULE
,
832 .type
= VID_TYPE_TELETEXT
,
834 .release
= video_device_release
,