At Mon, 10 Nov 2014 10:45:19 +1100, Damien Zammit wrote:
On 10/11/14 04:27, Takashi Iwai wrote:
At Sun, 09 Nov 2014 15:04:42 +0100, Clemens Ladisch wrote:
Takashi Iwai wrote:
I think the only point is the check in create_composite_quirk(), where it marks the iface as claimed and skips the next entry that has been already claimed. However, the current code looks inconsistent -- it allows multiple entries only if the iface matches with the current one. Fixing it like below would make things working.
It's a quick idea, so a bit more reviews would be needed, though. Clemens, what do you think?
Reviewed-by: Clemens Ladisch clemens@ladisch.de
--- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -58,9 +58,17 @@ static int create_composite_quirk(struct snd_usb_audio *chip, err = snd_usb_create_quirk(chip, iface, driver, quirk); if (err < 0) return err;
if (quirk->ifnum != probed_ifnum)
- }
- for (quirk = quirk->data; quirk->ifnum >= 0; ++quirk) {
iface = usb_ifnum_to_if(chip->dev, quirk->ifnum);if (!iface)continue;if (quirk->ifnum != probed_ifnum &&!usb_interface_claimed(iface)) usb_driver_claim_interface(driver, iface, (void *)-1L);- return 0;
}
When I tried the patch on the hardware with my quirk, I got a kernel oops.
My bad, take the additional fix patch below.
Takashi
-- 8< -- From: Takashi Iwai tiwai@suse.de Subject: [PATCH] ALSA: usb-audio: Fix Oops by composite quirk enhancement
The quirk argument itself was used as iterator, so it cannot be taken back to the original value, obviously.
Fixes: d4b8fc66f770 ('ALSA: usb-audio: Allow multiple entries for the same iface in composite quirk') Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/usb/quirks.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index e9ff3a6c60e4..809d7fab4633 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -43,12 +43,13 @@ static int create_composite_quirk(struct snd_usb_audio *chip, struct usb_interface *iface, struct usb_driver *driver, - const struct snd_usb_audio_quirk *quirk) + const struct snd_usb_audio_quirk *quirk_comp) { int probed_ifnum = get_iface_desc(iface->altsetting)->bInterfaceNumber; + const struct snd_usb_audio_quirk *quirk; int err;
- for (quirk = quirk->data; quirk->ifnum >= 0; ++quirk) { + for (quirk = quirk_comp->data; quirk->ifnum >= 0; ++quirk) { iface = usb_ifnum_to_if(chip->dev, quirk->ifnum); if (!iface) continue; @@ -60,7 +61,7 @@ static int create_composite_quirk(struct snd_usb_audio *chip, return err; }
- for (quirk = quirk->data; quirk->ifnum >= 0; ++quirk) { + for (quirk = quirk_comp->data; quirk->ifnum >= 0; ++quirk) { iface = usb_ifnum_to_if(chip->dev, quirk->ifnum); if (!iface) continue;