[alsa-devel] [PATCH v2] Add M2Tech hiFace USB-SPDIF driver

Takashi Iwai tiwai at suse.de
Fri Feb 22 13:52:38 CET 2013


At Fri, 22 Feb 2013 11:48:32 +0100,
Antonio Ospite wrote:
> 
> On Wed, 13 Feb 2013 18:11:45 +0100
> Antonio Ospite <ao2 at amarulasolutions.com> wrote:
> 
> > Add driver for M2Tech hiFace USB-SPDIF interface and compatible devices.
> > 
> > M2Tech hiFace and compatible devices offer a Hi-End S/PDIF Output
> > Interface, see http://www.m2tech.biz/hiface.html
> > 
> > The supported products are:
> > 
> >   * M2Tech Young
> >   * M2Tech hiFace
> >   * M2Tech North Star
> >   * M2Tech W4S Young
> >   * M2Tech Corrson
> >   * M2Tech AUDIA
> >   * M2Tech SL Audio
> >   * M2Tech Empirical
> >   * M2Tech Rockna
> >   * M2Tech Pathos
> >   * M2Tech Metronome
> >   * M2Tech CAD
> >   * M2Tech Audio Esclusive
> >   * M2Tech Rotel
> >   * M2Tech Eeaudio
> >   * The Chord Company CHORD
> >   * AVA Group A/S Vitus
> > 
> > Signed-off-by: Antonio Ospite <ao2 at amarulasolutions.com>
> > ---
> > 
> > Changes since v1:
> > 
> >   * Change the first sentence of the Kconfig entry into "Select this..."
> >   * Remove a useless sentence from the Kconfig entry
> >   * Don't set alsa_rt->hw.rates in hiface_pcm_open()
> >   * Style cleanup, no braces needed in single statement conditional
> >   * Remove the rate field from pcm_runtime
> >   * Use the hiFace name with the lowercase 'h' everywhere
> >   * List actually supported devices in MODULE_SUPPORTED_DEVICE()
> >   * Cosmetics, align values in the rates array
> >   * Use an explicit switch instead of the rate_value array in
> >     hiface_pcm_set_rate()
> >   * Use usb_make_path() when building card->longname
> >   * Use again the implicit mechanism to allocate the card private data
> >   * Downgrade a pr_info to pr_debug in hiface_chip_probe()
> >   * Make device_table const
> >   * Rename PCM_MAX_PACKET_SIZE to PCM_PACKET_SIZE
> >   * Rename MAX_BUFSIZE to PCM_BUFFER_SIZE
> >   * Cosmetics, align symbolic constant values
> >   * Add SNDRV_PCM_RATE_KNOT only when needed
> >   * Declare memcpy_swahw32() as static
> >   * Protect snd_pcm_stop() with snd_pcm_stream_lock_irq()
> >   * Make hiface_pcm_playback() not returning anything
> >   * Move the period elapsed check into hiface_pcm_playback()
> >   * Handle the case of failing URBs in hiface_pcm_out_urb_handler()
> >   * Fix a couple of checkpatch.pl issues
> > 
> > The incremental changes can be seen individually at
> > https://github.com/panicking/snd-usb-asyncaudio/commits/master
> > Commits from Feb. 10th and later.
> >
> 
> Ping.
> 
> Hi, I don't see this one in:
> http://git.kernel.org/?p=linux/kernel/git/tiwai/sound.git
> 
> If the code is OK, are we still in time for 3.9?

Sorry, I haven't reviewed the code yet (since I thought Clemens would
re-review at first :)  I'm inclined to merge only fix patches at this
point for 3.9, so the merge will be postponed to 3.10.

I'll take a look at the v2 patch.


Takashi


> 
> > Thanks,
> >    Antonio
> > 
> >  sound/usb/Kconfig         |   31 +++
> >  sound/usb/Makefile        |    2 +-
> >  sound/usb/hiface/Makefile |    2 +
> >  sound/usb/hiface/chip.h   |   34 +++
> >  sound/usb/hiface/chip.c   |  329 +++++++++++++++++++++++
> >  sound/usb/hiface/pcm.h    |   24 ++
> >  sound/usb/hiface/pcm.c    |  638 +++++++++++++++++++++++++++++++++++++++++++++
> >  7 files changed, 1059 insertions(+), 1 deletion(-)
> >  create mode 100644 sound/usb/hiface/Makefile
> >  create mode 100644 sound/usb/hiface/chip.h
> >  create mode 100644 sound/usb/hiface/chip.c
> >  create mode 100644 sound/usb/hiface/pcm.h
> >  create mode 100644 sound/usb/hiface/pcm.c
> > 
> > diff --git a/sound/usb/Kconfig b/sound/usb/Kconfig
> > index 225dfd7..de9408b 100644
> > --- a/sound/usb/Kconfig
> > +++ b/sound/usb/Kconfig
> > @@ -115,5 +115,36 @@ config SND_USB_6FIRE
> >            and further help can be found at
> >            http://sixfireusb.sourceforge.net
> >  
> > +config SND_USB_HIFACE
> > +        tristate "M2Tech hiFace USB-SPDIF driver"
> > +        select SND_PCM
> > +        help
> > +	  Select this option to include support for M2Tech hiFace USB-SPDIF
> > +	  interface.
> > +
> > +	  This driver supports the original M2Tech hiFace and some other
> > +	  compatible devices. The supported products are:
> > +
> > +	    * M2Tech Young
> > +	    * M2Tech hiFace
> > +	    * M2Tech North Star
> > +	    * M2Tech W4S Young
> > +	    * M2Tech Corrson
> > +	    * M2Tech AUDIA
> > +	    * M2Tech SL Audio
> > +	    * M2Tech Empirical
> > +	    * M2Tech Rockna
> > +	    * M2Tech Pathos
> > +	    * M2Tech Metronome
> > +	    * M2Tech CAD
> > +	    * M2Tech Audio Esclusive
> > +	    * M2Tech Rotel
> > +	    * M2Tech Eeaudio
> > +	    * The Chord Company CHORD
> > +	    * AVA Group A/S Vitus
> > +
> > +	  To compile this driver as a module, choose M here: the module
> > +	  will be called snd-usb-hiface.
> > +
> >  endif	# SND_USB
> >  
> > diff --git a/sound/usb/Makefile b/sound/usb/Makefile
> > index ac256dc..abe668f 100644
> > --- a/sound/usb/Makefile
> > +++ b/sound/usb/Makefile
> > @@ -23,4 +23,4 @@ obj-$(CONFIG_SND_USB_UA101) += snd-usbmidi-lib.o
> >  obj-$(CONFIG_SND_USB_USX2Y) += snd-usbmidi-lib.o
> >  obj-$(CONFIG_SND_USB_US122L) += snd-usbmidi-lib.o
> >  
> > -obj-$(CONFIG_SND) += misc/ usx2y/ caiaq/ 6fire/
> > +obj-$(CONFIG_SND) += misc/ usx2y/ caiaq/ 6fire/ hiface/
> > diff --git a/sound/usb/hiface/Makefile b/sound/usb/hiface/Makefile
> > new file mode 100644
> > index 0000000..463b136
> > --- /dev/null
> > +++ b/sound/usb/hiface/Makefile
> > @@ -0,0 +1,2 @@
> > +snd-usb-hiface-objs := chip.o pcm.o
> > +obj-$(CONFIG_SND_USB_HIFACE) += snd-usb-hiface.o
> > diff --git a/sound/usb/hiface/chip.h b/sound/usb/hiface/chip.h
> > new file mode 100644
> > index 0000000..cd615a0
> > --- /dev/null
> > +++ b/sound/usb/hiface/chip.h
> > @@ -0,0 +1,34 @@
> > +/*
> > + * Linux driver for M2Tech hiFace compatible devices
> > + *
> > + * Copyright 2012-2013 (C) M2TECH S.r.l and Amarula Solutions B.V.
> > + *
> > + * Authors:  Michael Trimarchi <michael at amarulasolutions.com>
> > + *           Antonio Ospite <ao2 at amarulasolutions.com>
> > + *
> > + * The driver is based on the work done in TerraTec DMX 6Fire USB
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + */
> > +
> > +#ifndef HIFACE_CHIP_H
> > +#define HIFACE_CHIP_H
> > +
> > +#include <linux/usb.h>
> > +#include <sound/core.h>
> > +
> > +struct pcm_runtime;
> > +
> > +struct hiface_chip {
> > +	struct usb_device *dev;
> > +	struct snd_card *card;
> > +	int intf_count; /* number of registered interfaces */
> > +	int index; /* index in module parameter arrays */
> > +	bool shutdown;
> > +
> > +	struct pcm_runtime *pcm;
> > +};
> > +#endif /* HIFACE_CHIP_H */
> > diff --git a/sound/usb/hiface/chip.c b/sound/usb/hiface/chip.c
> > new file mode 100644
> > index 0000000..f1293a5
> > --- /dev/null
> > +++ b/sound/usb/hiface/chip.c
> > @@ -0,0 +1,329 @@
> > +/*
> > + * Linux driver for M2Tech hiFace compatible devices
> > + *
> > + * Copyright 2012-2013 (C) M2TECH S.r.l and Amarula Solutions B.V.
> > + *
> > + * Authors:  Michael Trimarchi <michael at amarulasolutions.com>
> > + *           Antonio Ospite <ao2 at amarulasolutions.com>
> > + *
> > + * The driver is based on the work done in TerraTec DMX 6Fire USB
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/slab.h>
> > +#include <sound/initval.h>
> > +
> > +#include "chip.h"
> > +#include "pcm.h"
> > +
> > +MODULE_AUTHOR("Michael Trimarchi <michael at amarulasolutions.com>");
> > +MODULE_AUTHOR("Antonio Ospite <ao2 at amarulasolutions.com>");
> > +MODULE_DESCRIPTION("M2Tech hiFace USB-SPDIF audio driver");
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_SUPPORTED_DEVICE("{{M2Tech,Young},"
> > +			 "{M2Tech,hiFace},"
> > +			 "{M2Tech,North Star},"
> > +			 "{M2Tech,W4S Young},"
> > +			 "{M2Tech,Corrson},"
> > +			 "{M2Tech,AUDIA},"
> > +			 "{M2Tech,SL Audio},"
> > +			 "{M2Tech,Empirical},"
> > +			 "{M2Tech,Rockna},"
> > +			 "{M2Tech,Pathos},"
> > +			 "{M2Tech,Metronome},"
> > +			 "{M2Tech,CAD},"
> > +			 "{M2Tech,Audio Esclusive},"
> > +			 "{M2Tech,Rotel},"
> > +			 "{M2Tech,Eeaudio},"
> > +			 "{The Chord Company,CHORD},"
> > +			 "{AVA Group A/S,Vitus}}");
> > +
> > +static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-max */
> > +static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* Id for card */
> > +static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP; /* Enable this card */
> > +
> > +#define DRIVER_NAME "snd-usb-hiface"
> > +#define CARD_NAME "hiFace"
> > +
> > +module_param_array(index, int, NULL, 0444);
> > +MODULE_PARM_DESC(index, "Index value for " CARD_NAME " soundcard.");
> > +module_param_array(id, charp, NULL, 0444);
> > +MODULE_PARM_DESC(id, "ID string for " CARD_NAME " soundcard.");
> > +module_param_array(enable, bool, NULL, 0444);
> > +MODULE_PARM_DESC(enable, "Enable " CARD_NAME " soundcard.");
> > +
> > +static struct hiface_chip *chips[SNDRV_CARDS] = SNDRV_DEFAULT_PTR;
> > +
> > +static DEFINE_MUTEX(register_mutex);
> > +
> > +struct hiface_vendor_quirk {
> > +	const char *device_name;
> > +	u8 extra_freq;
> > +};
> > +
> > +static int hiface_chip_create(struct usb_device *device, int idx,
> > +			      const struct hiface_vendor_quirk *quirk,
> > +			      struct hiface_chip **rchip)
> > +{
> > +	struct snd_card *card = NULL;
> > +	struct hiface_chip *chip;
> > +	int ret;
> > +	int len;
> > +
> > +	*rchip = NULL;
> > +
> > +	/* if we are here, card can be registered in alsa. */
> > +	ret = snd_card_create(index[idx], id[idx], THIS_MODULE, sizeof(*chip), &card);
> > +	if (ret < 0) {
> > +		snd_printk(KERN_ERR "cannot create alsa card.\n");
> > +		return ret;
> > +	}
> > +
> > +	strcpy(card->driver, DRIVER_NAME);
> > +
> > +	if (quirk && quirk->device_name)
> > +		strcpy(card->shortname, quirk->device_name);
> > +	else
> > +		strcpy(card->shortname, "M2Tech generic audio");
> > +
> > +	strlcat(card->longname, card->shortname, sizeof(card->longname));
> > +	len = strlcat(card->longname, " at ", sizeof(card->longname));
> > +	if (len < sizeof(card->longname))
> > +		usb_make_path(device, card->longname + len,
> > +			      sizeof(card->longname) - len);
> > +
> > +	chip = card->private_data;
> > +	chip->dev = device;
> > +	chip->index = idx;
> > +	chip->card = card;
> > +
> > +	*rchip = chip;
> > +	return 0;
> > +}
> > +
> > +static int hiface_chip_probe(struct usb_interface *intf,
> > +			     const struct usb_device_id *usb_id)
> > +{
> > +	const struct hiface_vendor_quirk *quirk = (struct hiface_vendor_quirk *)usb_id->driver_info;
> > +	int ret;
> > +	int i;
> > +	struct hiface_chip *chip;
> > +	struct usb_device *device = interface_to_usbdev(intf);
> > +
> > +	pr_debug("Probe " DRIVER_NAME " driver.\n");
> > +
> > +	ret = usb_set_interface(device, 0, 0);
> > +	if (ret != 0) {
> > +		snd_printk(KERN_ERR "can't set first interface for " CARD_NAME " device.\n");
> > +		return -EIO;
> > +	}
> > +
> > +	/* check whether the card is already registered */
> > +	chip = NULL;
> > +	mutex_lock(&register_mutex);
> > +	for (i = 0; i < SNDRV_CARDS; i++) {
> > +		if (chips[i] && chips[i]->dev == device) {
> > +			if (chips[i]->shutdown) {
> > +				snd_printk(KERN_ERR CARD_NAME " device is in the shutdown state, cannot create a card instance\n");
> > +				ret = -ENODEV;
> > +				goto err;
> > +			}
> > +			chip = chips[i];
> > +			break;
> > +		}
> > +	}
> > +	if (!chip) {
> > +		/* it's a fresh one.
> > +		 * now look for an empty slot and create a new card instance
> > +		 */
> > +		for (i = 0; i < SNDRV_CARDS; i++)
> > +			if (enable[i] && !chips[i]) {
> > +				ret = hiface_chip_create(device, i, quirk,
> > +							 &chip);
> > +				if (ret < 0)
> > +					goto err;
> > +
> > +				snd_card_set_dev(chip->card, &intf->dev);
> > +				break;
> > +			}
> > +		if (!chip) {
> > +			snd_printk(KERN_ERR "no available " CARD_NAME " audio device\n");
> > +			ret = -ENODEV;
> > +			goto err;
> > +		}
> > +	}
> > +
> > +	ret = hiface_pcm_init(chip, quirk ? quirk->extra_freq : 0);
> > +	if (ret < 0)
> > +		goto err_chip_destroy;
> > +
> > +	ret = snd_card_register(chip->card);
> > +	if (ret < 0) {
> > +		snd_printk(KERN_ERR "cannot register " CARD_NAME " card\n");
> > +		goto err_chip_destroy;
> > +	}
> > +
> > +	chips[chip->index] = chip;
> > +	chip->intf_count++;
> > +
> > +	mutex_unlock(&register_mutex);
> > +
> > +	usb_set_intfdata(intf, chip);
> > +	return 0;
> > +
> > +err_chip_destroy:
> > +	snd_card_free(chip->card);
> > +err:
> > +	mutex_unlock(&register_mutex);
> > +	return ret;
> > +}
> > +
> > +static void hiface_chip_disconnect(struct usb_interface *intf)
> > +{
> > +	struct hiface_chip *chip;
> > +	struct snd_card *card;
> > +
> > +	pr_debug("%s: called.\n", __func__);
> > +
> > +	chip = usb_get_intfdata(intf);
> > +	if (!chip)
> > +		return;
> > +
> > +	card = chip->card;
> > +	chip->intf_count--;
> > +	if (chip->intf_count <= 0) {
> > +		/* Make sure that the userspace cannot create new request */
> > +		snd_card_disconnect(card);
> > +
> > +		mutex_lock(&register_mutex);
> > +		chips[chip->index] = NULL;
> > +		mutex_unlock(&register_mutex);
> > +
> > +		chip->shutdown = true;
> > +		hiface_pcm_abort(chip);
> > +		snd_card_free_when_closed(card);
> > +	}
> > +}
> > +
> > +static const struct usb_device_id device_table[] = {
> > +	{
> > +		USB_DEVICE(0x04b4, 0x0384),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Young",
> > +			.extra_freq = 1,
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x930b),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "hiFace",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x931b),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "North Star",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x931c),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "W4S Young",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x931d),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Corrson",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x931e),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "AUDIA",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x931f),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "SL Audio",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x9320),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Empirical",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x04b4, 0x9321),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Rockna",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x249c, 0x9001),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Pathos",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x249c, 0x9002),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Metronome",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x249c, 0x9006),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "CAD",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x249c, 0x9008),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Audio Esclusive",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x249c, 0x931c),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Rotel",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x249c, 0x932c),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Eeaudio",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x245f, 0x931c),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "CHORD",
> > +		}
> > +	},
> > +	{
> > +		USB_DEVICE(0x25c6, 0x9002),
> > +		.driver_info = (unsigned long)&(const struct hiface_vendor_quirk) {
> > +			.device_name = "Vitus",
> > +		}
> > +	},
> > +	{}
> > +};
> > +
> > +MODULE_DEVICE_TABLE(usb, device_table);
> > +
> > +static struct usb_driver hiface_usb_driver = {
> > +	.name = DRIVER_NAME,
> > +	.probe = hiface_chip_probe,
> > +	.disconnect = hiface_chip_disconnect,
> > +	.id_table = device_table,
> > +};
> > +
> > +module_usb_driver(hiface_usb_driver);
> > diff --git a/sound/usb/hiface/pcm.h b/sound/usb/hiface/pcm.h
> > new file mode 100644
> > index 0000000..77edd7c
> > --- /dev/null
> > +++ b/sound/usb/hiface/pcm.h
> > @@ -0,0 +1,24 @@
> > +/*
> > + * Linux driver for M2Tech hiFace compatible devices
> > + *
> > + * Copyright 2012-2013 (C) M2TECH S.r.l and Amarula Solutions B.V.
> > + *
> > + * Authors:  Michael Trimarchi <michael at amarulasolutions.com>
> > + *           Antonio Ospite <ao2 at amarulasolutions.com>
> > + *
> > + * The driver is based on the work done in TerraTec DMX 6Fire USB
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + */
> > +
> > +#ifndef HIFACE_PCM_H
> > +#define HIFACE_PCM_H
> > +
> > +struct hiface_chip;
> > +
> > +int hiface_pcm_init(struct hiface_chip *chip, u8 extra_freq);
> > +void hiface_pcm_abort(struct hiface_chip *chip);
> > +#endif /* HIFACE_PCM_H */
> > diff --git a/sound/usb/hiface/pcm.c b/sound/usb/hiface/pcm.c
> > new file mode 100644
> > index 0000000..d0c3c58
> > --- /dev/null
> > +++ b/sound/usb/hiface/pcm.c
> > @@ -0,0 +1,638 @@
> > +/*
> > + * Linux driver for M2Tech hiFace compatible devices
> > + *
> > + * Copyright 2012-2013 (C) M2TECH S.r.l and Amarula Solutions B.V.
> > + *
> > + * Authors:  Michael Trimarchi <michael at amarulasolutions.com>
> > + *           Antonio Ospite <ao2 at amarulasolutions.com>
> > + *
> > + * The driver is based on the work done in TerraTec DMX 6Fire USB
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + */
> > +
> > +#include <linux/slab.h>
> > +#include <sound/pcm.h>
> > +
> > +#include "pcm.h"
> > +#include "chip.h"
> > +
> > +#define OUT_EP          0x2
> > +#define PCM_N_URBS      8
> > +#define PCM_PACKET_SIZE 4096
> > +#define PCM_BUFFER_SIZE (2 * PCM_N_URBS * PCM_PACKET_SIZE)
> > +
> > +struct pcm_urb {
> > +	struct hiface_chip *chip;
> > +
> > +	struct urb instance;
> > +	struct usb_anchor submitted;
> > +	u8 *buffer;
> > +};
> > +
> > +struct pcm_substream {
> > +	spinlock_t lock;
> > +	struct snd_pcm_substream *instance;
> > +
> > +	bool active;
> > +	snd_pcm_uframes_t dma_off;    /* current position in alsa dma_area */
> > +	snd_pcm_uframes_t period_off; /* current position in current period */
> > +};
> > +
> > +enum { /* pcm streaming states */
> > +	STREAM_DISABLED, /* no pcm streaming */
> > +	STREAM_STARTING, /* pcm streaming requested, waiting to become ready */
> > +	STREAM_RUNNING,  /* pcm streaming running */
> > +	STREAM_STOPPING
> > +};
> > +
> > +struct pcm_runtime {
> > +	struct hiface_chip *chip;
> > +	struct snd_pcm *instance;
> > +
> > +	struct pcm_substream playback;
> > +	bool panic; /* if set driver won't do anymore pcm on device */
> > +
> > +	struct pcm_urb out_urbs[PCM_N_URBS];
> > +
> > +	struct mutex stream_mutex;
> > +	u8 stream_state; /* one of STREAM_XXX */
> > +	u8 extra_freq;
> > +	wait_queue_head_t stream_wait_queue;
> > +	bool stream_wait_cond;
> > +};
> > +
> > +static const unsigned int rates[] = { 44100, 48000, 88200, 96000, 176400, 192000,
> > +				      352800, 384000 };
> > +static const struct snd_pcm_hw_constraint_list constraints_extra_rates = {
> > +	.count = ARRAY_SIZE(rates),
> > +	.list = rates,
> > +	.mask = 0,
> > +};
> > +
> > +static const struct snd_pcm_hardware pcm_hw = {
> > +	.info = SNDRV_PCM_INFO_MMAP |
> > +		SNDRV_PCM_INFO_INTERLEAVED |
> > +		SNDRV_PCM_INFO_BLOCK_TRANSFER |
> > +		SNDRV_PCM_INFO_PAUSE |
> > +		SNDRV_PCM_INFO_MMAP_VALID |
> > +		SNDRV_PCM_INFO_BATCH,
> > +
> > +	.formats = SNDRV_PCM_FMTBIT_S32_LE,
> > +
> > +	.rates = SNDRV_PCM_RATE_44100 |
> > +		SNDRV_PCM_RATE_48000 |
> > +		SNDRV_PCM_RATE_88200 |
> > +		SNDRV_PCM_RATE_96000 |
> > +		SNDRV_PCM_RATE_176400 |
> > +		SNDRV_PCM_RATE_192000,
> > +
> > +	.rate_min = 44100,
> > +	.rate_max = 192000, /* changes in hiface_pcm_open to support extra rates */
> > +	.channels_min = 2,
> > +	.channels_max = 2,
> > +	.buffer_bytes_max = PCM_BUFFER_SIZE,
> > +	.period_bytes_min = PCM_PACKET_SIZE,
> > +	.period_bytes_max = PCM_BUFFER_SIZE,
> > +	.periods_min = 2,
> > +	.periods_max = 1024
> > +};
> > +
> > +/* message values used to change the sample rate */
> > +#define HIFACE_SET_RATE_REQUEST 0xb0
> > +
> > +#define HIFACE_RATE_44100  0x43
> > +#define HIFACE_RATE_48000  0x4b
> > +#define HIFACE_RATE_88200  0x42
> > +#define HIFACE_RATE_96000  0x4a
> > +#define HIFACE_RATE_176400 0x40
> > +#define HIFACE_RATE_192000 0x48
> > +#define HIFACE_RATE_352000 0x58
> > +#define HIFACE_RATE_384000 0x68
> > +
> > +static int hiface_pcm_set_rate(struct pcm_runtime *rt, unsigned int rate)
> > +{
> > +	struct usb_device *device = rt->chip->dev;
> > +	u16 rate_value;
> > +	int ret;
> > +
> > +	/* We are already sure that the rate is supported here thanks to
> > +	 * ALSA constraints
> > +	 */
> > +	switch (rate) {
> > +	case 44100:
> > +		rate_value = HIFACE_RATE_44100;
> > +		break;
> > +	case 48000:
> > +		rate_value = HIFACE_RATE_48000;
> > +		break;
> > +	case 88200:
> > +		rate_value = HIFACE_RATE_88200;
> > +		break;
> > +	case 96000:
> > +		rate_value = HIFACE_RATE_96000;
> > +		break;
> > +	case 176400:
> > +		rate_value = HIFACE_RATE_176400;
> > +		break;
> > +	case 192000:
> > +		rate_value = HIFACE_RATE_192000;
> > +		break;
> > +	case 352000:
> > +		rate_value = HIFACE_RATE_352000;
> > +		break;
> > +	case 384000:
> > +		rate_value = HIFACE_RATE_384000;
> > +		break;
> > +	default:
> > +		snd_printk(KERN_ERR "Unsupported rate %d\n", rate);
> > +		return -EINVAL;
> > +	}
> > +
> > +	/*
> > +	 * USBIO: Vendor 0xb0(wValue=0x0043, wIndex=0x0000)
> > +	 * 43 b0 43 00 00 00 00 00
> > +	 * USBIO: Vendor 0xb0(wValue=0x004b, wIndex=0x0000)
> > +	 * 43 b0 4b 00 00 00 00 00
> > +	 * This control message doesn't have any ack from the
> > +	 * other side
> > +	 */
> > +	ret = usb_control_msg(device, usb_sndctrlpipe(device, 0),
> > +				HIFACE_SET_RATE_REQUEST,
> > +				USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
> > +				rate_value, 0, NULL, 0, 100);
> > +	if (ret < 0) {
> > +		snd_printk(KERN_ERR "Error setting samplerate %d.\n", rate);
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static struct pcm_substream *hiface_pcm_get_substream(
> > +		struct snd_pcm_substream *alsa_sub)
> > +{
> > +	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
> > +
> > +	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
> > +		return &rt->playback;
> > +
> > +	pr_debug("Error getting pcm substream slot.\n");
> > +	return NULL;
> > +}
> > +
> > +/* call with stream_mutex locked */
> > +static void hiface_pcm_stream_stop(struct pcm_runtime *rt)
> > +{
> > +	int i, time;
> > +
> > +	if (rt->stream_state != STREAM_DISABLED) {
> > +		rt->stream_state = STREAM_STOPPING;
> > +
> > +		for (i = 0; i < PCM_N_URBS; i++) {
> > +			time = usb_wait_anchor_empty_timeout(
> > +					&rt->out_urbs[i].submitted, 100);
> > +			if (!time)
> > +				usb_kill_anchored_urbs(
> > +					&rt->out_urbs[i].submitted);
> > +			usb_kill_urb(&rt->out_urbs[i].instance);
> > +		}
> > +
> > +		rt->stream_state = STREAM_DISABLED;
> > +	}
> > +}
> > +
> > +/* call with stream_mutex locked */
> > +static int hiface_pcm_stream_start(struct pcm_runtime *rt)
> > +{
> > +	int ret = 0, i;
> > +
> > +	if (rt->stream_state == STREAM_DISABLED) {
> > +		/* submit our out urbs zero init */
> > +		rt->stream_state = STREAM_STARTING;
> > +		for (i = 0; i < PCM_N_URBS; i++) {
> > +			memset(rt->out_urbs[i].buffer, 0, PCM_PACKET_SIZE);
> > +			usb_anchor_urb(&rt->out_urbs[i].instance,
> > +				       &rt->out_urbs[i].submitted);
> > +			ret = usb_submit_urb(&rt->out_urbs[i].instance,
> > +					GFP_ATOMIC);
> > +			if (ret) {
> > +				hiface_pcm_stream_stop(rt);
> > +				return ret;
> > +			}
> > +		}
> > +
> > +		/* wait for first out urb to return (sent in in urb handler) */
> > +		wait_event_timeout(rt->stream_wait_queue, rt->stream_wait_cond,
> > +				HZ);
> > +		if (rt->stream_wait_cond) {
> > +			pr_debug("%s: Stream is running wakeup event\n",
> > +				 __func__);
> > +			rt->stream_state = STREAM_RUNNING;
> > +		} else {
> > +			hiface_pcm_stream_stop(rt);
> > +			return -EIO;
> > +		}
> > +	}
> > +	return ret;
> > +}
> > +
> > +
> > +/* The hardware wants word-swapped 32-bit values */
> > +static void memcpy_swahw32(u8 *dest, u8 *src, unsigned int n)
> > +{
> > +	unsigned int i;
> > +
> > +	for (i = 0; i < n / 4; i++)
> > +		((u32 *)dest)[i] = swahw32(((u32 *)src)[i]);
> > +}
> > +
> > +/* call with substream locked */
> > +/* returns true if a period elapsed */
> > +static bool hiface_pcm_playback(struct pcm_substream *sub,
> > +		struct pcm_urb *urb)
> > +{
> > +	struct snd_pcm_runtime *alsa_rt = sub->instance->runtime;
> > +	u8 *source;
> > +	unsigned int pcm_buffer_size;
> > +
> > +	WARN_ON(alsa_rt->format != SNDRV_PCM_FORMAT_S32_LE);
> > +
> > +	pcm_buffer_size = snd_pcm_lib_buffer_bytes(sub->instance);
> > +
> > +	if (sub->dma_off + PCM_PACKET_SIZE <= pcm_buffer_size) {
> > +		pr_debug("%s: (1) buffer_size %#x dma_offset %#x\n", __func__,
> > +			 (unsigned int) pcm_buffer_size,
> > +			 (unsigned int) sub->dma_off);
> > +
> > +		source = alsa_rt->dma_area + sub->dma_off;
> > +		memcpy_swahw32(urb->buffer, source, PCM_PACKET_SIZE);
> > +	} else {
> > +		/* wrap around at end of ring buffer */
> > +		unsigned int len;
> > +
> > +		pr_debug("%s: (2) buffer_size %#x dma_offset %#x\n", __func__,
> > +			 (unsigned int) pcm_buffer_size,
> > +			 (unsigned int) sub->dma_off);
> > +
> > +		len = pcm_buffer_size - sub->dma_off;
> > +
> > +		source = alsa_rt->dma_area + sub->dma_off;
> > +		memcpy_swahw32(urb->buffer, source, len);
> > +
> > +		source = alsa_rt->dma_area;
> > +		memcpy_swahw32(urb->buffer + len, source,
> > +			       PCM_PACKET_SIZE - len);
> > +	}
> > +	sub->dma_off += PCM_PACKET_SIZE;
> > +	if (sub->dma_off >= pcm_buffer_size)
> > +		sub->dma_off -= pcm_buffer_size;
> > +
> > +	sub->period_off += PCM_PACKET_SIZE;
> > +	if (sub->period_off >= alsa_rt->period_size) {
> > +		sub->period_off %= alsa_rt->period_size;
> > +		return true;
> > +	}
> > +	return false;
> > +}
> > +
> > +static void hiface_pcm_out_urb_handler(struct urb *usb_urb)
> > +{
> > +	struct pcm_urb *out_urb = usb_urb->context;
> > +	struct pcm_runtime *rt = out_urb->chip->pcm;
> > +	struct pcm_substream *sub;
> > +	bool do_period_elapsed = false;
> > +	unsigned long flags;
> > +	int ret;
> > +
> > +	pr_debug("%s: called.\n", __func__);
> > +
> > +	if (rt->panic || rt->stream_state == STREAM_STOPPING)
> > +		return;
> > +
> > +	if (unlikely(usb_urb->status == -ENOENT ||	/* unlinked */
> > +		     usb_urb->status == -ENODEV ||	/* device removed */
> > +		     usb_urb->status == -ECONNRESET ||	/* unlinked */
> > +		     usb_urb->status == -ESHUTDOWN)) {	/* device disabled */
> > +		goto out_fail;
> > +	}
> > +
> > +	if (rt->stream_state == STREAM_STARTING) {
> > +		rt->stream_wait_cond = true;
> > +		wake_up(&rt->stream_wait_queue);
> > +	}
> > +
> > +	/* now send our playback data (if a free out urb was found) */
> > +	sub = &rt->playback;
> > +	spin_lock_irqsave(&sub->lock, flags);
> > +	if (sub->active)
> > +		do_period_elapsed = hiface_pcm_playback(sub, out_urb);
> > +	else
> > +		memset(out_urb->buffer, 0, PCM_PACKET_SIZE);
> > +
> > +	spin_unlock_irqrestore(&sub->lock, flags);
> > +
> > +	if (do_period_elapsed)
> > +		snd_pcm_period_elapsed(sub->instance);
> > +
> > +	ret = usb_submit_urb(&out_urb->instance, GFP_ATOMIC);
> > +	if (ret < 0)
> > +		goto out_fail;
> > +
> > +	return;
> > +
> > +out_fail:
> > +	rt->panic = true;
> > +}
> > +
> > +static int hiface_pcm_open(struct snd_pcm_substream *alsa_sub)
> > +{
> > +	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
> > +	struct pcm_substream *sub = NULL;
> > +	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
> > +	int ret;
> > +
> > +	pr_debug("%s: called.\n", __func__);
> > +
> > +	if (rt->panic)
> > +		return -EPIPE;
> > +
> > +	mutex_lock(&rt->stream_mutex);
> > +	alsa_rt->hw = pcm_hw;
> > +
> > +	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
> > +		sub = &rt->playback;
> > +
> > +	if (!sub) {
> > +		mutex_unlock(&rt->stream_mutex);
> > +		pr_err("Invalid stream type\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (rt->extra_freq) {
> > +		alsa_rt->hw.rates |= SNDRV_PCM_RATE_KNOT;
> > +		alsa_rt->hw.rate_max = 384000;
> > +
> > +		/* explicit constraints needed as we added SNDRV_PCM_RATE_KNOT */
> > +		ret = snd_pcm_hw_constraint_list(alsa_sub->runtime, 0,
> > +						 SNDRV_PCM_HW_PARAM_RATE,
> > +						 &constraints_extra_rates);
> > +		if (ret < 0) {
> > +			mutex_unlock(&rt->stream_mutex);
> > +			return ret;
> > +		}
> > +	}
> > +
> > +	sub->instance = alsa_sub;
> > +	sub->active = false;
> > +	mutex_unlock(&rt->stream_mutex);
> > +	return 0;
> > +}
> > +
> > +static int hiface_pcm_close(struct snd_pcm_substream *alsa_sub)
> > +{
> > +	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
> > +	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
> > +	unsigned long flags;
> > +
> > +	if (rt->panic)
> > +		return 0;
> > +
> > +	pr_debug("%s: called.\n", __func__);
> > +
> > +	mutex_lock(&rt->stream_mutex);
> > +	if (sub) {
> > +		/* deactivate substream */
> > +		spin_lock_irqsave(&sub->lock, flags);
> > +		sub->instance = NULL;
> > +		sub->active = false;
> > +		spin_unlock_irqrestore(&sub->lock, flags);
> > +
> > +		/* all substreams closed? if so, stop streaming */
> > +		if (!rt->playback.instance)
> > +			hiface_pcm_stream_stop(rt);
> > +	}
> > +	mutex_unlock(&rt->stream_mutex);
> > +	return 0;
> > +}
> > +
> > +static int hiface_pcm_hw_params(struct snd_pcm_substream *alsa_sub,
> > +		struct snd_pcm_hw_params *hw_params)
> > +{
> > +	pr_debug("%s: called.\n", __func__);
> > +	return snd_pcm_lib_malloc_pages(alsa_sub,
> > +			params_buffer_bytes(hw_params));
> > +}
> > +
> > +static int hiface_pcm_hw_free(struct snd_pcm_substream *alsa_sub)
> > +{
> > +	pr_debug("%s: called.\n", __func__);
> > +	return snd_pcm_lib_free_pages(alsa_sub);
> > +}
> > +
> > +static int hiface_pcm_prepare(struct snd_pcm_substream *alsa_sub)
> > +{
> > +	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
> > +	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
> > +	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
> > +	int ret;
> > +
> > +	pr_debug("%s: called.\n", __func__);
> > +
> > +	if (rt->panic)
> > +		return -EPIPE;
> > +	if (!sub)
> > +		return -ENODEV;
> > +
> > +	mutex_lock(&rt->stream_mutex);
> > +
> > +	sub->dma_off = 0;
> > +	sub->period_off = 0;
> > +
> > +	if (rt->stream_state == STREAM_DISABLED) {
> > +
> > +		ret = hiface_pcm_set_rate(rt, alsa_rt->rate);
> > +		if (ret) {
> > +			mutex_unlock(&rt->stream_mutex);
> > +			return ret;
> > +		}
> > +		ret = hiface_pcm_stream_start(rt);
> > +		if (ret) {
> > +			mutex_unlock(&rt->stream_mutex);
> > +			return ret;
> > +		}
> > +	}
> > +	mutex_unlock(&rt->stream_mutex);
> > +	return 0;
> > +}
> > +
> > +static int hiface_pcm_trigger(struct snd_pcm_substream *alsa_sub, int cmd)
> > +{
> > +	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
> > +	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
> > +	unsigned long flags;
> > +
> > +	pr_debug("%s: called.\n", __func__);
> > +
> > +	if (rt->panic)
> > +		return -EPIPE;
> > +	if (!sub)
> > +		return -ENODEV;
> > +
> > +	switch (cmd) {
> > +	case SNDRV_PCM_TRIGGER_START:
> > +	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
> > +		spin_lock_irqsave(&sub->lock, flags);
> > +		sub->active = true;
> > +		spin_unlock_irqrestore(&sub->lock, flags);
> > +		return 0;
> > +
> > +	case SNDRV_PCM_TRIGGER_STOP:
> > +	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
> > +		spin_lock_irqsave(&sub->lock, flags);
> > +		sub->active = false;
> > +		spin_unlock_irqrestore(&sub->lock, flags);
> > +		return 0;
> > +
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +}
> > +
> > +static snd_pcm_uframes_t hiface_pcm_pointer(struct snd_pcm_substream *alsa_sub)
> > +{
> > +	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
> > +	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
> > +	unsigned long flags;
> > +	snd_pcm_uframes_t dma_offset;
> > +
> > +	if (rt->panic || !sub)
> > +		return SNDRV_PCM_STATE_XRUN;
> > +
> > +	spin_lock_irqsave(&sub->lock, flags);
> > +	dma_offset = sub->dma_off;
> > +	spin_unlock_irqrestore(&sub->lock, flags);
> > +	return bytes_to_frames(alsa_sub->runtime, dma_offset);
> > +}
> > +
> > +static struct snd_pcm_ops pcm_ops = {
> > +	.open = hiface_pcm_open,
> > +	.close = hiface_pcm_close,
> > +	.ioctl = snd_pcm_lib_ioctl,
> > +	.hw_params = hiface_pcm_hw_params,
> > +	.hw_free = hiface_pcm_hw_free,
> > +	.prepare = hiface_pcm_prepare,
> > +	.trigger = hiface_pcm_trigger,
> > +	.pointer = hiface_pcm_pointer,
> > +};
> > +
> > +static int hiface_pcm_init_urb(struct pcm_urb *urb,
> > +			       struct hiface_chip *chip,
> > +			       unsigned int ep,
> > +			       void (*handler)(struct urb *))
> > +{
> > +	urb->chip = chip;
> > +	usb_init_urb(&urb->instance);
> > +
> > +	urb->buffer = kzalloc(PCM_PACKET_SIZE, GFP_KERNEL);
> > +	if (!urb->buffer)
> > +		return -ENOMEM;
> > +
> > +	usb_fill_bulk_urb(&urb->instance, chip->dev,
> > +			  usb_sndbulkpipe(chip->dev, ep), (void *)urb->buffer,
> > +			  PCM_PACKET_SIZE, handler, urb);
> > +	init_usb_anchor(&urb->submitted);
> > +
> > +	return 0;
> > +}
> > +
> > +void hiface_pcm_abort(struct hiface_chip *chip)
> > +{
> > +	struct pcm_runtime *rt = chip->pcm;
> > +
> > +	if (rt) {
> > +		rt->panic = true;
> > +
> > +		if (rt->playback.instance) {
> > +			snd_pcm_stream_lock_irq(rt->playback.instance);
> > +			snd_pcm_stop(rt->playback.instance,
> > +					SNDRV_PCM_STATE_XRUN);
> > +			snd_pcm_stream_unlock_irq(rt->playback.instance);
> > +		}
> > +		mutex_lock(&rt->stream_mutex);
> > +		hiface_pcm_stream_stop(rt);
> > +		mutex_unlock(&rt->stream_mutex);
> > +	}
> > +}
> > +
> > +static void hiface_pcm_destroy(struct hiface_chip *chip)
> > +{
> > +	struct pcm_runtime *rt = chip->pcm;
> > +	int i;
> > +
> > +	for (i = 0; i < PCM_N_URBS; i++)
> > +		kfree(rt->out_urbs[i].buffer);
> > +
> > +	kfree(chip->pcm);
> > +	chip->pcm = NULL;
> > +}
> > +
> > +static void hiface_pcm_free(struct snd_pcm *pcm)
> > +{
> > +	struct pcm_runtime *rt = pcm->private_data;
> > +
> > +	pr_debug("%s: called.\n", __func__);
> > +
> > +	if (rt)
> > +		hiface_pcm_destroy(rt->chip);
> > +}
> > +
> > +int hiface_pcm_init(struct hiface_chip *chip, u8 extra_freq)
> > +{
> > +	int i;
> > +	int ret;
> > +	struct snd_pcm *pcm;
> > +	struct pcm_runtime *rt;
> > +
> > +	rt = kzalloc(sizeof(*rt), GFP_KERNEL);
> > +	if (!rt)
> > +		return -ENOMEM;
> > +
> > +	rt->chip = chip;
> > +	rt->stream_state = STREAM_DISABLED;
> > +	if (extra_freq)
> > +		rt->extra_freq = 1;
> > +
> > +	init_waitqueue_head(&rt->stream_wait_queue);
> > +	mutex_init(&rt->stream_mutex);
> > +	spin_lock_init(&rt->playback.lock);
> > +
> > +	for (i = 0; i < PCM_N_URBS; i++)
> > +		hiface_pcm_init_urb(&rt->out_urbs[i], chip, OUT_EP,
> > +				hiface_pcm_out_urb_handler);
> > +
> > +	ret = snd_pcm_new(chip->card, "USB-SPDIF Audio", 0, 1, 0, &pcm);
> > +	if (ret < 0) {
> > +		kfree(rt);
> > +		pr_err("Cannot create pcm instance\n");
> > +		return ret;
> > +	}
> > +
> > +	pcm->private_data = rt;
> > +	pcm->private_free = hiface_pcm_free;
> > +
> > +	strcpy(pcm->name, "USB-SPDIF Audio");
> > +	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &pcm_ops);
> > +
> > +	snd_pcm_lib_preallocate_pages_for_all(pcm,
> > +					SNDRV_DMA_TYPE_CONTINUOUS,
> > +					snd_dma_continuous_data(GFP_KERNEL),
> > +					PCM_BUFFER_SIZE, PCM_BUFFER_SIZE);
> > +	rt->instance = pcm;
> > +
> > +	chip->pcm = rt;
> > +	return 0;
> > +}
> > -- 
> > 1.7.10.4
> > 
> > _______________________________________________
> > Alsa-devel mailing list
> > Alsa-devel at alsa-project.org
> > http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
> 
> 
> -- 
> Antonio Ospite
> http://ao2.it
> 
> A: Because it messes up the order in which people normally read text.
>    See http://en.wikipedia.org/wiki/Posting_style
> Q: Why is top-posting such a bad thing?
> 


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