[alsa-devel] [PATCH] MIDI driver for Behringer BCD2000 USB device

[Mario Kicherer]

Hi Daniel,

thank you very much for your comments! I hope I fixed most of the
points but I also have a few questions/comments:

On 05.02.2014 11:54, Daniel Mack wrote:
>> +#ifdef CONFIG_USB_DEBUG
>> +#define DEBUG	1
>> +#else
>> +#define DEBUG	0
>> +#endif
>
> Please use the define directly instead of introducing a new one.

I replaced it with:

#ifndef CONFIG_USB_DEBUG
#define CONFIG_USB_DEBUG 0
#endif

As it can be undefined. I hope that's okay.

> Your patch has a huge number of style issues, which
> scripts/checkpatch.pl will point you to. I got:

Interesting, I copied many issues from other modules. :)
If fixed most of them except these:

WARNING: quoted string split across lines
#310: FILE: sound/usb/bcd2000/bcd2000.c:254:
+                       "bcd2000_midi_send(%p): usb_submit_urb() failed"
+                       "ret=%d, len=%d\n", substream, ret, len);

WARNING: quoted string split across lines
#392: FILE: sound/usb/bcd2000/bcd2000.c:336:
+                               "bcd2000_init_device: usb_submit_urb() 
failed,"
+                               "ret=%d: ", ret);

I don't know how to avoid them, as all strings in one line would be
longer than 80 characters.

>> +		/* determine the number of bytes we want to copy this time */
>> +		tocopy = min( 3 - bcd2k->midi_cmd_offset, length - (buf_offset - 1));
>> +		
>> +		if (tocopy > 0) {
>
> tocopy is unsigned char, so this check is always true, and the copy
> routine can overflow in case bcd2k->midi_cmd_offset < 3.

I don't understand your point here. It could be zero. But I changed it
to a condition that checks if both offsets are within the length of the
two involved buffers.

> Please, no dead code. Remove those lines entirely if you don't need them.

Ah okay, I planned to reactive them with the audio part. But I removed
them for now.

As far as I understood, I should repost the new patch as [PATCH v2]. I
will check this evening if the device still works and send it to the
list afterwards.

Thank you!
Mario