[PATCH] dvb: flexcop: readme update

state of the new flexcop-driver set and some internals are written down here

too.

How to do something in here?

============================

make -f Makefile.t

make -C ../build-2.6

./in.sh  # load the drivers

./rm.sh  # unload the drivers

Please read this file, if you want to contribute.

This document hopefully describes things about the flexcop and its

device-offsprings. Goal is to write a easy-to-write and easy-to-read set of

device-offsprings. Goal was to write an easy-to-write and easy-to-read set of

drivers based on the skystar2.c and other information.

This directory is temporary. It is used for rewriting the skystar2.c and to

create shared code, which then can be used by the usb box as well.

Remark: flexcop-pci.c was a copy of skystar2.c, but every line has been

touched and rewritten.

History & News

==============

  2005-04-01 - correct USB ISOC transfers (thanks to Vadim Catana)

General coding processing

=========================

2) Search for errors in the leftover of flexcop-pci.c (partially done)

5a) add MAC address reading

5c) feeding of ISOC data to the software demux (format of the isochronous data

and speed optimization, no real error) (thanks to Vadim Catana)

What to do in the near future?

--------------------------------------

(no special order here)

5) USB driver

5b) optimize isoc-transfer (submitting/killing isoc URBs when transfer is starting)

5c) feeding of ISOC data to the software demux (format of the isochronous data

and speed optimization, no real error)

Testing changes

---------------

2)     |                 O                 |                 N

5a)    |                 N                 |                 O

5b)*   |                 N                 |

5c)*   |                 N                 |

5c)    |                 N                 |                 O

* - not done yet

SOLUTION: also index 0 was affected, because net_translation is done for

these indexes by default

5b) isochronous transfer does only work in the first attempt (for the Sky2PC USB,

Air2PC is working)

SOLUTION: the flexcop was going asleep and never really woke up again (don't

know if this need fixes, see flexcop-fe-tuner.c:flexcop_sleep)

5b) isochronous transfer does only work in the first attempt (for the Sky2PC

USB, Air2PC is working) SOLUTION: the flexcop was going asleep and never really

woke up again (don't know if this need fixes, see

flexcop-fe-tuner.c:flexcop_sleep)

NEWS: when the driver is loaded and unloaded and loaded again (w/o doing

anything in the while the driver is loaded the first time), no transfers take

place anymore.

Improvements when rewriting (refactoring) is done

=================================================

- split sleeping of the flexcop (misc_204.ACPI3_sig = 1;) from lnb_control

  (enable sleeping for other demods than dvb-s)

- add support for CableStar (stv0297 Microtune 203x/ALPS)

- add support for CableStar (stv0297 Microtune 203x/ALPS) (almost done, incompatibilities with the Nexus-CA)

Debugging

---------

Tuner/Demod:                     I2C bus

DVB-stuff:            can be written for common use

Restrictions:

============

We need to create a bus-specific-struct and a flexcop-struct.

bus-specific-struct:

struct flexcop_pci

...

struct flexcop_usb

...

struct flexcop_device {

	void *bus_specific; /* container for bus-specific struct */

...

}

PCI i2c can read/write max 4 bytes at a time, USB can more

Functions

=========

Syntax

------

- Flexcop functions will be called "flexcop(_[a-z0-9]+)+" and exported as such

  if needed.

- Flexcop-device functions will be called "flexcop_device(_[a-z0-9]+)+" and

  exported as such if needed.

- Both will be compiled to b2c2-flexcop.ko and their source can be found in the

  flexcop*.[hc]

Callbacks and exports

---------------------

Bus-specific functions will be given as callbacks (function pointers) to the

flexcop-module. (within the flexcop_device-struct)

Initialization process

======================

b2c2-flexcop.ko is loaded

b2c2-flexcop-<bus>.ko is loaded

suppose a device is found:

malloc flexcop and the bus-specific variables (via flexcop_device_malloc)

fill the bus-specific variable

fill the flexcop variable (especially the bus-specific callbacks)

bus-specific initialization

	- ...

do the common initialization (via flexcop_device_initialize)

	- reset the card

	- determine flexcop type (II, IIB, III)

	- hw_filters (bus dependent)

	- 0x204

	- set sram size

	- create the dvb-stuff

	- create i2c stuff

	- frontend-initialization

done

bus specific:

	- media_destination (this and the following 3 are bus specific)

	- cai_dest

	- cao_dest

	- net_destination

Bugs fixed while rewriting the driver

=====================================

- EEPROM access (to read the MAC address) was fixed to death some time last

  year. (fixed here and in skystar2.c) (Bjarne, this was the piece of code

  (fix-chipaddr) we were wondering about)

Acknowledgements (just for the rewriting part)

================

Vadim Catana for correcting the USB transfer.

comments, critics and ideas to linux-dvb@linuxtv.org or patrick.boettcher@desy.de

comments, critics and ideas to linux-dvb@linuxtv.org.