Re: [ANNOUNCE] usbmon capture and parser script

[Greg KH <greg@kroah.com>]

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