From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Courtier-Dutton <James@superbug.demon.co.uk>
Subject: usb audio callback questions.
Date: Sun, 06 Jul 2003 14:21:52 +0100
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To: alsa-devel <alsa-devel@lists.sourceforge.net>
List-Id: alsa-devel@alsa-project.org

I have a question regarding the callbacks in the usbaudio.c driver.
The callback is defined as: -

/*
  * complete callback from data urb
  */
static void snd_complete_urb(struct urb *urb, struct pt_regs *regs)


The callback is set up with: -
u->urb->complete = snd_usb_complete_callback(snd_complete_urb);

The issue I have is that urb->complete is of type: -
struct urb;
typedef void (*usb_complete_t)(struct urb *);

struct urb
{
<snip>
         usb_complete_t complete;        // pointer to completion routine
<snip>
};

So, why is the "struct pt_regs *regs" there ?
I would think that
static void snd_complete_urb(struct urb *urb, struct pt_regs *regs)
should change to
static void snd_complete_urb(struct urb *urb)

Cheers
James



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