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Diffstat (limited to 'Documentation/media/v4l-drivers/cx88.rst')
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diff --git a/Documentation/media/v4l-drivers/cx88.rst b/Documentation/media/v4l-drivers/cx88.rst deleted file mode 100644 index 698c73ea2e36..000000000000 --- a/Documentation/media/v4l-drivers/cx88.rst +++ /dev/null @@ -1,165 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -The cx88 driver -=============== - -Author: Gerd Hoffmann - -This is a v4l2 device driver for the cx2388x chip. - - -Current status --------------- - -video - - Works. - - Overlay isn't supported. - -audio - - Works. The TV standard detection is made by the driver, as the - hardware has bugs to auto-detect. - - audio data dma (i.e. recording without loopback cable to the - sound card) is supported via cx88-alsa. - -vbi - - Works. - - -How to add support for new cards --------------------------------- - -The driver needs some config info for the TV cards. This stuff is in -cx88-cards.c. If the driver doesn't work well you likely need a new -entry for your card in that file. Check the kernel log (using dmesg) -to see whenever the driver knows your card or not. There is a line -like this one: - -.. code-block:: none - - cx8800[0]: subsystem: 0070:3400, board: Hauppauge WinTV \ - 34xxx models [card=1,autodetected] - -If your card is listed as "board: UNKNOWN/GENERIC" it is unknown to -the driver. What to do then? - -1) Try upgrading to the latest snapshot, maybe it has been added - meanwhile. -2) You can try to create a new entry yourself, have a look at - cx88-cards.c. If that worked, mail me your changes as unified - diff ("diff -u"). -3) Or you can mail me the config information. We need at least the - following information to add the card: - - - the PCI Subsystem ID ("0070:3400" from the line above, - "lspci -v" output is fine too). - - the tuner type used by the card. You can try to find one by - trial-and-error using the tuner=<n> insmod option. If you - know which one the card has you can also have a look at the - list in CARDLIST.tuner - -Documentation missing at the cx88 datasheet -------------------------------------------- - -MO_OUTPUT_FORMAT (0x310164) - -.. code-block:: none - - Previous default from DScaler: 0x1c1f0008 - Digit 8: 31-28 - 28: PREVREMOD = 1 - - Digit 7: 27-24 (0xc = 12 = b1100 ) - 27: COMBALT = 1 - 26: PAL_INV_PHASE - (DScaler apparently set this to 1, resulted in sucky picture) - - Digits 6,5: 23-16 - 25-16: COMB_RANGE = 0x1f [default] (9 bits -> max 512) - - Digit 4: 15-12 - 15: DISIFX = 0 - 14: INVCBF = 0 - 13: DISADAPT = 0 - 12: NARROWADAPT = 0 - - Digit 3: 11-8 - 11: FORCE2H - 10: FORCEREMD - 9: NCHROMAEN - 8: NREMODEN - - Digit 2: 7-4 - 7-6: YCORE - 5-4: CCORE - - Digit 1: 3-0 - 3: RANGE = 1 - 2: HACTEXT - 1: HSFMT - -0x47 is the sync byte for MPEG-2 transport stream packets. -Datasheet incorrectly states to use 47 decimal. 188 is the length. -All DVB compliant frontends output packets with this start code. - -Hauppauge WinTV cx88 IR information ------------------------------------ - -The controls for the mux are GPIO [0,1] for source, and GPIO 2 for muting. - -====== ======== ================================================= -GPIO0 GPIO1 -====== ======== ================================================= - 0 0 TV Audio - 1 0 FM radio - 0 1 Line-In - 1 1 Mono tuner bypass or CD passthru (tuner specific) -====== ======== ================================================= - -GPIO 16(I believe) is tied to the IR port (if present). - - -From the data sheet: - -- Register 24'h20004 PCI Interrupt Status - - - bit [18] IR_SMP_INT Set when 32 input samples have been collected over - - gpio[16] pin into GP_SAMPLE register. - -What's missing from the data sheet: - -- Setup 4KHz sampling rate (roughly 2x oversampled; good enough for our RC5 - compat remote) -- set register 0x35C050 to 0xa80a80 -- enable sampling -- set register 0x35C054 to 0x5 -- enable the IRQ bit 18 in the interrupt mask register (and - provide for a handler) - -GP_SAMPLE register is at 0x35C058 - -Bits are then right shifted into the GP_SAMPLE register at the specified -rate; you get an interrupt when a full DWORD is received. -You need to recover the actual RC5 bits out of the (oversampled) IR sensor -bits. (Hint: look for the 0/1and 1/0 crossings of the RC5 bi-phase data) An -actual raw RC5 code will span 2-3 DWORDS, depending on the actual alignment. - -I'm pretty sure when no IR signal is present the receiver is always in a -marking state(1); but stray light, etc can cause intermittent noise values -as well. Remember, this is a free running sample of the IR receiver state -over time, so don't assume any sample starts at any particular place. - -Additional info -~~~~~~~~~~~~~~~ - -This data sheet (google search) seems to have a lovely description of the -RC5 basics: -http://www.atmel.com/dyn/resources/prod_documents/doc2817.pdf - -This document has more data: -http://www.nenya.be/beor/electronics/rc5.htm - -This document has a how to decode a bi-phase data stream: -http://www.ee.washington.edu/circuit_archive/text/ir_decode.txt - -This document has still more info: -http://www.xs4all.nl/~sbp/knowledge/ir/rc5.htm |