Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756585Ab3EJO0D (ORCPT ); Fri, 10 May 2013 10:26:03 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:57297 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755939Ab3EJOWD (ORCPT ); Fri, 10 May 2013 10:22:03 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Calvin Owens" , "Takashi Iwai" Date: Fri, 10 May 2013 14:39:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [028/118] ALSA: usb: Add quirk for 192KHz recording on E-Mu devices In-Reply-To: X-SA-Exim-Connect-IP: 2001:470:1f08:1539:d51a:8785:aa0a:cebe X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2797 Lines: 73 3.2.45-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Calvin Owens commit 1539d4f82ad534431cc67935e8e442ccf107d17d upstream. When recording at 176.2KHz or 192Khz, the device adds a 32-bit length header to the capture packets, which obviously needs to be ignored for recording to work properly. Userspace expected: L0 L1 L2 R0 R1 R2 ...but actually got: R2 L0 L1 L2 R0 R1 Also, the last byte of the length header being interpreted as L0 of the first sample caused spikes every 0.5ms, resulting in a loud 16KHz tone (about the highest 'B' on a piano) being present throughout captures. Tested at all sample rates on an E-Mu 0404USB, and tested for regressions on a generic USB headset. Signed-off-by: Calvin Owens Signed-off-by: Takashi Iwai [bwh: Backported to 3.2: adjust filenames, context] Signed-off-by: Ben Hutchings --- --- a/sound/usb/card.h +++ b/sound/usb/card.h @@ -73,6 +73,7 @@ struct snd_usb_substream { unsigned int fill_max: 1; /* fill max packet size always */ unsigned int txfr_quirk:1; /* allow sub-frame alignment */ unsigned int fmt_type; /* USB audio format type (1-3) */ + unsigned int pkt_offset_adj; /* Bytes to drop from beginning of packets (for non-compliant devices) */ unsigned int running: 1; /* running status */ --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -458,7 +458,7 @@ static int retire_capture_urb(struct snd stride = runtime->frame_bits >> 3; for (i = 0; i < urb->number_of_packets; i++) { - cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset; + cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj; if (urb->iso_frame_desc[i].status && printk_ratelimit()) { snd_printdd("frame %d active: %d\n", i, urb->iso_frame_desc[i].status); // continue; @@ -898,6 +898,7 @@ void snd_usb_init_substream(struct snd_u subs->speed = snd_usb_get_speed(subs->dev); if (subs->speed >= USB_SPEED_HIGH) subs->ops.prepare_sync = prepare_capture_sync_urb_hs; + subs->pkt_offset_adj = 0; snd_usb_set_pcm_ops(as->pcm, stream); --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -744,6 +744,7 @@ static void set_format_emu_quirk(struct break; } snd_emuusb_set_samplerate(subs->stream->chip, emu_samplerate_id); + subs->pkt_offset_adj = (emu_samplerate_id >= EMU_QUIRK_SR_176400HZ) ? 4 : 0; } void snd_usb_set_format_quirk(struct snd_usb_substream *subs, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/