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Johannes Stezenbach2add87a2005-05-16 21:54:10 -07001This README escorted the skystar2-driver rewriting procedure. It describes the
2state of the new flexcop-driver set and some internals are written down here
3too.
4
Johannes Stezenbach2add87a2005-05-16 21:54:10 -07005This document hopefully describes things about the flexcop and its
Johannes Stezenbachc6ee1972005-05-16 21:54:17 -07006device-offsprings. Goal was to write an easy-to-write and easy-to-read set of
Johannes Stezenbach2add87a2005-05-16 21:54:10 -07007drivers based on the skystar2.c and other information.
8
Johannes Stezenbach2add87a2005-05-16 21:54:10 -07009Remark: flexcop-pci.c was a copy of skystar2.c, but every line has been
10touched and rewritten.
11
Johannes Stezenbachc6ee1972005-05-16 21:54:17 -070012History & News
13==============
14 2005-04-01 - correct USB ISOC transfers (thanks to Vadim Catana)
15
16
17
18
Johannes Stezenbach2add87a2005-05-16 21:54:10 -070019General coding processing
20=========================
21
22We should proceed as follows (as long as no one complains):
23
240) Think before start writing code!
25
261) rewriting the skystar2.c with the help of the flexcop register descriptions
27and splitting up the files to a pci-bus-part and a flexcop-part.
28The new driver will be called b2c2-flexcop-pci.ko/b2c2-flexcop-usb.ko for the
29device-specific part and b2c2-flexcop.ko for the common flexcop-functions.
30
312) Search for errors in the leftover of flexcop-pci.c (compare with pluto2.c
32and other pci drivers)
33
343) make some beautification (see 'Improvements when rewriting (refactoring) is
35done')
36
374) Testing the new driver and maybe substitute the skystar2.c with it, to reach
38a wider tester audience.
39
405) creating an usb-bus-part using the already written flexcop code for the pci
41card.
42
43Idea: create a kernel-object for the flexcop and export all important
44functions. This option saves kernel-memory, but maybe a lot of functions have
45to be exported to kernel namespace.
46
47
48Current situation
49=================
50
510) Done :)
521) Done (some minor issues left)
532) Done
543) Not ready yet, more information is necessary
554) next to be done (see the table below)
565) USB driver is working (yes, there are some minor issues)
57
58What seems to be ready?
59-----------------------
60
611) Rewriting
621a) i2c is cut off from the flexcop-pci.c and seems to work
631b) moved tuner and demod stuff from flexcop-pci.c to flexcop-tuner-fe.c
641c) moved lnb and diseqc stuff from flexcop-pci.c to flexcop-tuner-fe.c
651e) eeprom (reading MAC address)
661d) sram (no dynamic sll size detection (commented out) (using default as JJ told me))
671f) misc. register accesses for reading parameters (e.g. resetting, revision)
681g) pid/mac filter (flexcop-hw-filter.c)
691i) dvb-stuff initialization in flexcop.c (done)
701h) dma stuff (now just using the size-irq, instead of all-together, to be done)
711j) remove flexcop initialization from flexcop-pci.c completely (done)
721l) use a well working dma IRQ method (done, see 'Known bugs and problems and TODO')
731k) cleanup flexcop-files (remove unused EXPORT_SYMBOLs, make static from
74non-static where possible, moved code to proper places)
75
762) Search for errors in the leftover of flexcop-pci.c (partially done)
775a) add MAC address reading
Johannes Stezenbachc6ee1972005-05-16 21:54:17 -0700785c) feeding of ISOC data to the software demux (format of the isochronous data
79and speed optimization, no real error) (thanks to Vadim Catana)
Johannes Stezenbach2add87a2005-05-16 21:54:10 -070080
81What to do in the near future?
82--------------------------------------
83(no special order here)
84
Johannes Stezenbach2add87a2005-05-16 21:54:10 -0700855) USB driver
865b) optimize isoc-transfer (submitting/killing isoc URBs when transfer is starting)
Johannes Stezenbach2add87a2005-05-16 21:54:10 -070087
88Testing changes
89---------------
90
91O = item is working
92P = item is partially working
93X = item is not working
94N = item does not apply here
95<empty field> = item need to be examined
96
97 | PCI | USB
98item | mt352 | nxt2002 | stv0299 | mt312 | mt352 | nxt2002 | stv0299 | mt312
99-------+-------+---------+---------+-------+-------+---------+---------+-------
1001a) | O | | | | N | N | N | N
1011b) | O | | | | | | O |
1021c) | N | N | | | N | N | O |
1031d) | O | O
1041e) | O | O
1051f) | P
1061g) | O
1071h) | P |
1081i) | O | N
1091j) | O | N
1101l) | O | N
1112) | O | N
1125a) | N | O
1135b)* | N |
Johannes Stezenbachc6ee1972005-05-16 21:54:17 -07001145c) | N | O
Johannes Stezenbach2add87a2005-05-16 21:54:10 -0700115
116* - not done yet
117
118Known bugs and problems and TODO
119--------------------------------
120
1211g/h/l) when pid filtering is enabled on the pci card
122
123DMA usage currently:
124 The DMA is splitted in 2 equal-sized subbuffers. The Flexcop writes to first
125 address and triggers an IRQ when it's full and starts writing to the second
126 address. When the second address is full, the IRQ is triggered again, and
127 the flexcop writes to first address again, and so on.
128 The buffersize of each address is currently 640*188 bytes.
129
130 Problem is, when using hw-pid-filtering and doing some low-bandwidth
131 operation (like scanning) the buffers won't be filled enough to trigger
132 the IRQ. That's why:
133
134 When PID filtering is activated, the timer IRQ is used. Every 1.97 ms the IRQ
135 is triggered. Is the current write address of DMA1 different to the one
136 during the last IRQ, then the data is passed to the demuxer.
137
138 There is an additional DMA-IRQ-method: packet count IRQ. This isn't
139 implemented correctly yet.
140
141 The solution is to disable HW PID filtering, but I don't know how the DVB
142 API software demux behaves on slow systems with 45MBit/s TS.
143
144Solved bugs :)
145--------------
1461g) pid-filtering (somehow pid index 4 and 5 (EMM_PID and ECM_PID) aren't
147working)
148SOLUTION: also index 0 was affected, because net_translation is done for
149these indexes by default
150
Johannes Stezenbachc6ee1972005-05-16 21:54:17 -07001515b) isochronous transfer does only work in the first attempt (for the Sky2PC
152USB, Air2PC is working) SOLUTION: the flexcop was going asleep and never really
153woke up again (don't know if this need fixes, see
154flexcop-fe-tuner.c:flexcop_sleep)
155
156NEWS: when the driver is loaded and unloaded and loaded again (w/o doing
157anything in the while the driver is loaded the first time), no transfers take
158place anymore.
Johannes Stezenbach2add87a2005-05-16 21:54:10 -0700159
160Improvements when rewriting (refactoring) is done
161=================================================
162
163- split sleeping of the flexcop (misc_204.ACPI3_sig = 1;) from lnb_control
164 (enable sleeping for other demods than dvb-s)
Johannes Stezenbachc6ee1972005-05-16 21:54:17 -0700165- add support for CableStar (stv0297 Microtune 203x/ALPS) (almost done, incompatibilities with the Nexus-CA)
Johannes Stezenbach2add87a2005-05-16 21:54:10 -0700166
167Debugging
168---------
169- add verbose debugging to skystar2.c (dump the reg_dw_data) and compare it
170 with this flexcop, this is important, because i2c is now using the
171 flexcop_ibi_value union from flexcop-reg.h (do you have a better idea for
172 that, please tell us so).
173
174Everything which is identical in the following table, can be put into a common
175flexcop-module.
176
177 PCI USB
178-------------------------------------------------------------------------------
179Different:
180Register access: accessing IO memory USB control message
181I2C bus: I2C bus of the FC USB control message
182Data transfer: DMA isochronous transfer
183EEPROM transfer: through i2c bus not clear yet
184
185Identical:
186Streaming: accessing registers
187PID Filtering: accessing registers
188Sram destinations: accessing registers
189Tuner/Demod: I2C bus
190DVB-stuff: can be written for common use
191
Johannes Stezenbach2add87a2005-05-16 21:54:10 -0700192Acknowledgements (just for the rewriting part)
193================
194
195Bjarne Steinsbo thought a lot in the first place of the pci part for this code
196sharing idea.
197
Johannes Stezenbach3ed8a312005-05-16 21:54:13 -0700198Andreas Oberritter for providing a recent PCI initialization template
199(pluto2.c).
200
201Boleslaw Ciesielski for pointing out a problem with firmware loader.
202
203Vadim Catana for correcting the USB transfer.
Johannes Stezenbach2add87a2005-05-16 21:54:10 -0700204
Johannes Stezenbachc6ee1972005-05-16 21:54:17 -0700205comments, critics and ideas to linux-dvb@linuxtv.org.