|  | This README escorted the skystar2-driver rewriting procedure. It describes the | 
|  | state of the new flexcop-driver set and some internals are written down here | 
|  | too. | 
|  |  | 
|  | This document hopefully describes things about the flexcop and its | 
|  | 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. | 
|  |  | 
|  | 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 | 
|  | ========================= | 
|  |  | 
|  | We should proceed as follows (as long as no one complains): | 
|  |  | 
|  | 0) Think before start writing code! | 
|  |  | 
|  | 1) rewriting the skystar2.c with the help of the flexcop register descriptions | 
|  | and splitting up the files to a pci-bus-part and a flexcop-part. | 
|  | The new driver will be called b2c2-flexcop-pci.ko/b2c2-flexcop-usb.ko for the | 
|  | device-specific part and b2c2-flexcop.ko for the common flexcop-functions. | 
|  |  | 
|  | 2) Search for errors in the leftover of flexcop-pci.c (compare with pluto2.c | 
|  | and other pci drivers) | 
|  |  | 
|  | 3) make some beautification (see 'Improvements when rewriting (refactoring) is | 
|  | done') | 
|  |  | 
|  | 4) Testing the new driver and maybe substitute the skystar2.c with it, to reach | 
|  | a wider tester audience. | 
|  |  | 
|  | 5) creating an usb-bus-part using the already written flexcop code for the pci | 
|  | card. | 
|  |  | 
|  | Idea: create a kernel-object for the flexcop and export all important | 
|  | functions. This option saves kernel-memory, but maybe a lot of functions have | 
|  | to be exported to kernel namespace. | 
|  |  | 
|  |  | 
|  | Current situation | 
|  | ================= | 
|  |  | 
|  | 0) Done :) | 
|  | 1) Done (some minor issues left) | 
|  | 2) Done | 
|  | 3) Not ready yet, more information is necessary | 
|  | 4) next to be done (see the table below) | 
|  | 5) USB driver is working (yes, there are some minor issues) | 
|  |  | 
|  | What seems to be ready? | 
|  | ----------------------- | 
|  |  | 
|  | 1) Rewriting | 
|  | 1a) i2c is cut off from the flexcop-pci.c and seems to work | 
|  | 1b) moved tuner and demod stuff from flexcop-pci.c to flexcop-tuner-fe.c | 
|  | 1c) moved lnb and diseqc stuff from flexcop-pci.c to flexcop-tuner-fe.c | 
|  | 1e) eeprom (reading MAC address) | 
|  | 1d) sram (no dynamic sll size detection (commented out) (using default as JJ told me)) | 
|  | 1f) misc. register accesses for reading parameters (e.g. resetting, revision) | 
|  | 1g) pid/mac filter (flexcop-hw-filter.c) | 
|  | 1i) dvb-stuff initialization in flexcop.c (done) | 
|  | 1h) dma stuff (now just using the size-irq, instead of all-together, to be done) | 
|  | 1j) remove flexcop initialization from flexcop-pci.c completely (done) | 
|  | 1l) use a well working dma IRQ method (done, see 'Known bugs and problems and TODO') | 
|  | 1k) cleanup flexcop-files (remove unused EXPORT_SYMBOLs, make static from | 
|  | non-static where possible, moved code to proper places) | 
|  |  | 
|  | 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) | 
|  |  | 
|  | Testing changes | 
|  | --------------- | 
|  |  | 
|  | O             = item is working | 
|  | P             = item is partially working | 
|  | X             = item is not working | 
|  | N             = item does not apply here | 
|  | <empty field> = item need to be examined | 
|  |  | 
|  | | PCI                               | USB | 
|  | item   | mt352 | nxt2002 | stv0299 | mt312 | mt352 | nxt2002 | stv0299 | mt312 | 
|  | -------+-------+---------+---------+-------+-------+---------+---------+------- | 
|  | 1a)    | O     |         |         |       | N     | N       | N       | N | 
|  | 1b)    | O     |         |         |       |       |         | O       | | 
|  | 1c)    | N     | N       |         |       | N     | N       | O       | | 
|  | 1d)    |                 O                 |                 O | 
|  | 1e)    |                 O                 |                 O | 
|  | 1f)    |                                   P | 
|  | 1g)    |                                   O | 
|  | 1h)    |                 P                 | | 
|  | 1i)    |                 O                 |                 N | 
|  | 1j)    |                 O                 |                 N | 
|  | 1l)    |                 O                 |                 N | 
|  | 2)     |                 O                 |                 N | 
|  | 5a)    |                 N                 |                 O | 
|  | 5b)*   |                 N                 | | 
|  | 5c)    |                 N                 |                 O | 
|  |  | 
|  | * - not done yet | 
|  |  | 
|  | Known bugs and problems and TODO | 
|  | -------------------------------- | 
|  |  | 
|  | 1g/h/l) when pid filtering is enabled on the pci card | 
|  |  | 
|  | DMA usage currently: | 
|  | The DMA is splitted in 2 equal-sized subbuffers. The Flexcop writes to first | 
|  | address and triggers an IRQ when it's full and starts writing to the second | 
|  | address. When the second address is full, the IRQ is triggered again, and | 
|  | the flexcop writes to first address again, and so on. | 
|  | The buffersize of each address is currently 640*188 bytes. | 
|  |  | 
|  | Problem is, when using hw-pid-filtering and doing some low-bandwidth | 
|  | operation (like scanning) the buffers won't be filled enough to trigger | 
|  | the IRQ. That's why: | 
|  |  | 
|  | When PID filtering is activated, the timer IRQ is used. Every 1.97 ms the IRQ | 
|  | is triggered.  Is the current write address of DMA1 different to the one | 
|  | during the last IRQ, then the data is passed to the demuxer. | 
|  |  | 
|  | There is an additional DMA-IRQ-method: packet count IRQ. This isn't | 
|  | implemented correctly yet. | 
|  |  | 
|  | The solution is to disable HW PID filtering, but I don't know how the DVB | 
|  | API software demux behaves on slow systems with 45MBit/s TS. | 
|  |  | 
|  | Solved bugs :) | 
|  | -------------- | 
|  | 1g) pid-filtering (somehow pid index 4 and 5 (EMM_PID and ECM_PID) aren't | 
|  | working) | 
|  | 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) | 
|  |  | 
|  | 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) (almost done, incompatibilities with the Nexus-CA) | 
|  |  | 
|  | Debugging | 
|  | --------- | 
|  | - add verbose debugging to skystar2.c (dump the reg_dw_data) and compare it | 
|  | with this flexcop, this is important, because i2c is now using the | 
|  | flexcop_ibi_value union from flexcop-reg.h (do you have a better idea for | 
|  | that, please tell us so). | 
|  |  | 
|  | Everything which is identical in the following table, can be put into a common | 
|  | flexcop-module. | 
|  |  | 
|  | PCI                  USB | 
|  | ------------------------------------------------------------------------------- | 
|  | Different: | 
|  | Register access:  accessing IO memory  USB control message | 
|  | I2C bus:          I2C bus of the FC    USB control message | 
|  | Data transfer:    DMA                  isochronous transfer | 
|  | EEPROM transfer:  through i2c bus      not clear yet | 
|  |  | 
|  | Identical: | 
|  | Streaming:                 accessing registers | 
|  | PID Filtering:             accessing registers | 
|  | Sram destinations:         accessing registers | 
|  | Tuner/Demod:                     I2C bus | 
|  | DVB-stuff:            can be written for common use | 
|  |  | 
|  | Acknowledgements (just for the rewriting part) | 
|  | ================ | 
|  |  | 
|  | Bjarne Steinsbo thought a lot in the first place of the pci part for this code | 
|  | sharing idea. | 
|  |  | 
|  | Andreas Oberritter for providing a recent PCI initialization template | 
|  | (pluto2.c). | 
|  |  | 
|  | Boleslaw Ciesielski for pointing out a problem with firmware loader. | 
|  |  | 
|  | Vadim Catana for correcting the USB transfer. | 
|  |  | 
|  | comments, critics and ideas to linux-dvb@linuxtv.org. |