On Wed, Mar 16, 2011 at 03:34:17PM -0300, Mauro Carvalho Chehab wrote: > While trying to debug some issues on a driver on Linux, and using a Beagleboard card as a > hardware USB sniffer[1], I noticed the need of having a parser to work with > the sniffer data. While wireshark provides a good way of looking into the info, > most of the times, I just want to convert the data into something more concise > that allows me to work on a char terminal, and that allows to use a device-specific > parser that translates an obscure log into device-specific register reads and writes. > > [1] using the code available at: http://beagleboard-usbsniffer.blogspot.com/ > > So, I wrote a parser, in perl, called parse_tcpdump_log.pl. The current version > is, in fact, more than a parser, as it allows both parsing a previously captured > log, or to start a capture and parse data in real time. The script is available > at the v4l-utils tree, on: > http://git.linuxtv.org/v4l-utils.git?a=blob;f=contrib/parse_tcpdump_log.pl;h=f90e981125462a58cadefa607cbff0ecb4b5ed45;hb=HEAD > > At the output, each line is a URB data control transfer. The script groups the > request and the complete URB's into one line, so, each line of the dump > will correspond to a call to usb_control_msg(). > > The output is: > > 000000000 ms 000000 ms (000127 us EP=80) 80 06 00 01 00 00 28 00 >>> 12 01 00 02 00 00 00 40 40 20 13 65 10 01 00 01 02 01 > 000000000 ms 000000 ms (000002 us EP=80) 80 06 00 01 00 00 28 00 >>> 12 01 00 02 09 00 00 40 6b 1d 02 00 06 02 03 02 01 01 > 000000006 ms 000005 ms (000239 us EP=80) c0 00 00 00 45 00 03 00 <<< 00 00 10 > 000001006 ms 001000 ms (000112 us EP=80) c0 00 00 00 45 00 03 00 <<< 00 00 10 > 000001106 ms 000100 ms (000150 us EP=80) c0 00 00 00 45 00 03 00 <<< 00 00 10 > > The provided info on each of the above lines are: > > - Time from the script start; > - Time from the last transaction; > - Time between URB send request and URB response; > - Endpoint for the transfer; > - 8 bytes with the following URB fields: > - Type (1 byte); > - Request (1 byte); > - wValue (2 bytes); > - wIndex (2 bytes); > - wLength (2 bytes); > - URB direction: > >>> - To URB device > <<< - To host > - Optional data (length is given by wLength). > > It is also possible to produce a detailed log, when used with "--debug 2", like: > > PARSED data: > RAW: ID => 0xffff880105a53f00 > RAW: Payload => 00000000000000000000000000000000000200000000000012010002090000406b1d0200060203020101 > RAW: Time => 1300309970.745112 > RAW: Status => 0 > RAW: ArrivalTime => 5584788795812741120.745112 > RAW: URBLength => 18 > RAW: TransferType => 2 > RAW: Device => 1 > RAW: Type => C > RAW: DataLength => 18 > RAW: BusID => 1 > RAW: HasData => present > RAW: Endpoint => 128 > RAW: PayloadSize => 42 > RAW: SetupRequest => not present > > There are a few other parsers at the v4l-utils git tree that can work with the > default output format and produce a device-specific output. For example, the > parser_em28xx.pl will produce a code that will look close to the C clauses > inside the em28xx driver. So, for a real-time debug of the em28xx driver, for > example, it will do: > > # ./parse_tcpdump_log.pl --pcap |./parse_em28xx.pl > > em28xx_read_reg(dev, EM28XX_R26_COMPR); /* read 0x0c */ > em28xx_write_reg(dev, EM28XX_R26_COMPR, 0x0c); > i2c_master_send(0xb8>>1, { 02 00 }, 0x02); > i2c_master_send(0xb8>>1, { 00 00 }, 0x02); > i2c_master_send(0xb8>>1, { 03 }, 0x01); > i2c_master_recv(0xb8>>1, &buf, 0x01); /* 6f */ > em28xx_read_reg(dev, 0x05); /* read 0x00 */ > i2c_master_send(0xb8>>1, { 03 6f }, 0x02); > em28xx_write_ac97(dev, AC97_MASTER_VOL, 0x8000); > em28xx_write_ac97(dev, AC97_LINE_LEVEL_VOL, 0x8000); > em28xx_write_ac97(dev, AC97_MASTER_MONO_VOL, 0x8000); > em28xx_write_ac97(dev, AC97_LFE_MASTER_VOL, 0x8000); > > I wrote a short summary on how to use it at: > http://linuxtv.org/wiki/index.php/Bus_snooping/sniffing#Snooping_Procedures: > > The script also accepts the "--man" and "--help" parameters to produce a manpage > or a help. > > In summary, I hope that this script will ease USB device driver debug and development. Very cool stuff. You are away of: http://vusb-analyzer.sourceforge.net/ right? I know you are doing this in console mode, but it looks close to the same idea. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
