Subject: Re: [PATCH 0/3 V3.1] can/usb: Add PEAK-System PCAN USB adapters driver

From: Wolfgang Grandegger <[email-masked]>
Date: Fri, 20 Jan 2012 10:28:41 +0100

On 01/19/2012 08:08 PM, Oliver Hartkopp wrote:
> On 19.01.2012 11:27, Stephane Grosjean wrote:
> 
>> That serie of patches adds the peak_usb driver which handles the PCAN-USB
>> and PCAN-USB Pro adapters from PEAK-System (http://www.peak-system.com).
>> These patches are planned for kernel v3.02.00 and above.
> 
> 
> Hello Stephane,
> 
> i tried your patch with Linus' current tree (3.3 merge).
> 
> Plugging-in the PEAK USB adapter it turns out to be *very* informative in
> the kernel log and also presents information twice:
> 
> [  153.566193] usb 2-1.2: new full-speed USB device number 6 using ehci_hcd
> [  153.663659] usb 2-1.2: New USB device found, idVendor=0c72, idProduct=000c
> [  153.663665] usb 2-1.2: New USB device strings: Mfr=0, Product=3, SerialNumber=0
> [  153.663669] usb 2-1.2: Product: VER1:PEAK    
> [  153.663671] VER2:02.8.01        
> [  153.663672] DAT :06.05.2004
> [  153.663672] TIME:09:35:37
> [  153.663673]                              ...
> [  153.682683] peak_usb: PCAN-USB interfaces driver loaded
> [  153.682736] peak_usb 2-1.2:1.0: new PEAK-System usb adapter with 1 can detected:
> [  153.682741] peak_usb 2-1.2:1.0: PEAK-System PCAN-USB
> [  153.682746] peak_usb 2-1.2:1.0: VER1:PEAK    .VER2:02.8.01        .DAT :06.05.2004.TIME:09:35:37.                             ...
> [  153.685422] peak_usb 2-1.2:1.0: serial FFFFFFFF hwrev 28
> [  153.686413] peak_usb 2-1.2:1.0: can2 attached to PCAN-USB can 0 (device 46)
> [  153.686521] usbcore: registered new interface driver peak_usb

I already realized that the driver produces a lot of output... that's
definitely too much.

> As i assume that this VER2/DAT/TIME stuff and also the "..." line comes
> somewhere from the device itself and is printed by the USB stack, i wonder if
> we could reduce the information provided by the peak_usb driver then.
> 
> E.g.
> 
> [  153.682683] peak_usb: PCAN-USB interfaces driver loaded
> # is obsolete as peak_usb speaks to us in the following lines
> 
> [  153.682736] peak_usb 2-1.2:1.0: new PEAK-System usb adapter with 1 can detected:
> [  153.682741] peak_usb 2-1.2:1.0: PEAK-System PCAN-USB
> # Can be merged, e.g. to
> [  153.682741] peak_usb 2-1.2:1.0: PEAK-System PCAN-USB adapter hwrev 28 (one channel)
> 
> 
> [  153.682746] peak_usb 2-1.2:1.0: VER1:PEAK    .VER2:02.8.01        .DAT :06.05.2004.TIME:09:35:37.                             ...
> # If you think, this is still needed(???) -> at least kill the spaces like this:
> [  153.682746] peak_usb 2-1.2:1.0: VER1:PEAK.VER2:02.8.01.DAT:06.05.2004.TIME:09:35:37....

If it's valuable information, we could also use dev_dbg().

> [  153.685422] peak_usb 2-1.2:1.0: serial FFFFFFFF hwrev 28
> [  153.686413] peak_usb 2-1.2:1.0: can2 attached to PCAN-USB can 0 (device 46)
> # Can be merged, e.g. to
> [  153.686413] peak_usb 2-1.2:1.0: PCAN-USB channel 0 (serial FFFFFFFF, device 46) attached to can2
> 
> So it would finally look like this (6 -> 2 lines):
> 
> [  153.682741] peak_usb 2-1.2:1.0: PEAK-System PCAN-USB adapter hwrev 28 (one channel)
> [  153.686413] peak_usb 2-1.2:1.0: PCAN-USB channel 0 (serial FFFFFFFF, device 46) attached to can2
> 
> I'm not sure, if the serial number was identical when having two channels like in the USB-Pro.
> If so the serial number in general could be moved up like this:
> 
> [  153.682741] peak_usb 2-1.2:1.0: PEAK-System PCAN-USB adapter hwrev 28 serial FFFFFFFF (one channel)
> [  153.686413] peak_usb 2-1.2:1.0: PCAN-USB channel 0 (device 46) attached to can2

Just 2 lines, that would be prefect. Please also check the output of the
PCAN-USB-Pro device and try to reduce it to 2+- lines as well.

Wolfgang.