| 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. |
