1 files changed, 311 insertions, 0 deletions

diff --git a/sound/usb/clock.c b/sound/usb/clock.c
new file mode 100644
index 0000000..b7aadd6
--- /dev/null
+++ b/sound/usb/clock.c
@@ -0,0 +1,311 @@
+/*
+ *   Clock domain and sample rate management functions
+ *
+ *   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.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/usb.h>
+#include <linux/moduleparam.h>
+#include <linux/mutex.h>
+#include <linux/usb/audio.h>
+#include <linux/usb/audio-v2.h>
+
+#include <sound/core.h>
+#include <sound/info.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+
+#include "usbaudio.h"
+#include "card.h"
+#include "midi.h"
+#include "mixer.h"
+#include "proc.h"
+#include "quirks.h"
+#include "endpoint.h"
+#include "helper.h"
+#include "debug.h"
+#include "pcm.h"
+#include "urb.h"
+#include "format.h"
+
+static struct uac_clock_source_descriptor *
+	snd_usb_find_clock_source(struct usb_host_interface *ctrl_iface,
+				  int clock_id)
+{
+	struct uac_clock_source_descriptor *cs = NULL;
+
+	while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
+					     ctrl_iface->extralen,
+					     cs, UAC2_CLOCK_SOURCE))) {
+		if (cs->bClockID == clock_id)
+			return cs;
+	}
+
+	return NULL;
+}
+
+static struct uac_clock_selector_descriptor *
+	snd_usb_find_clock_selector(struct usb_host_interface *ctrl_iface,
+				    int clock_id)
+{
+	struct uac_clock_selector_descriptor *cs = NULL;
+
+	while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
+					     ctrl_iface->extralen,
+					     cs, UAC2_CLOCK_SELECTOR))) {
+		if (cs->bClockID == clock_id)
+			return cs;
+	}
+
+	return NULL;
+}
+
+static struct uac_clock_multiplier_descriptor *
+	snd_usb_find_clock_multiplier(struct usb_host_interface *ctrl_iface,
+				      int clock_id)
+{
+	struct uac_clock_multiplier_descriptor *cs = NULL;
+
+	while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
+					     ctrl_iface->extralen,
+					     cs, UAC2_CLOCK_MULTIPLIER))) {
+		if (cs->bClockID == clock_id)
+			return cs;
+	}
+
+	return NULL;
+}
+
+static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
+{
+	unsigned char buf;
+	int ret;
+
+	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
+			      UAC2_CS_CUR,
+			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+			      UAC2_CX_CLOCK_SELECTOR << 8, selector_id << 8,
+			      &buf, sizeof(buf), 1000);
+
+	if (ret < 0)
+		return ret;
+
+	return buf;
+}
+
+static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id)
+{
+	int err;
+	unsigned char data;
+	struct usb_device *dev = chip->dev;
+
+	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
+			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
+			      UAC2_CS_CONTROL_CLOCK_VALID << 8, source_id << 8,
+			      &data, sizeof(data), 1000);
+
+	if (err < 0) {
+		snd_printk(KERN_WARNING "%s(): cannot get clock validity for id %d\n",
+			   __func__, source_id);
+		return err;
+	}
+
+	return !!data;
+}
+
+/* Try to find the clock source ID of a given clock entity */
+
+static int __uac_clock_find_source(struct snd_usb_audio *chip,
+				   struct usb_host_interface *host_iface,
+				   int entity_id, unsigned long *visited)
+{
+	struct uac_clock_source_descriptor *source;
+	struct uac_clock_selector_descriptor *selector;
+	struct uac_clock_multiplier_descriptor *multiplier;
+
+	entity_id &= 0xff;
+
+	if (test_and_set_bit(entity_id, visited)) {
+		snd_printk(KERN_WARNING
+			"%s(): recursive clock topology detected, id %d.\n",
+			__func__, entity_id);
+		return -EINVAL;
+	}
+
+	/* first, see if the ID we're looking for is a clock source already */
+	source = snd_usb_find_clock_source(host_iface, entity_id);
+	if (source)
+		return source->bClockID;
+
+	selector = snd_usb_find_clock_selector(host_iface, entity_id);
+	if (selector) {
+		int ret;
+
+		/* the entity ID we are looking for is a selector.
+		 * find out what it currently selects */
+		ret = uac_clock_selector_get_val(chip, selector->bClockID);
+		if (ret < 0)
+			return ret;
+
+		if (ret > selector->bNrInPins || ret < 1) {
+			printk(KERN_ERR
+				"%s(): selector reported illegal value, id %d, ret %d\n",
+				__func__, selector->bClockID, ret);
+
+			return -EINVAL;
+		}
+
+		return __uac_clock_find_source(chip, host_iface,
+					       selector->baCSourceID[ret-1],
+					       visited);
+	}
+
+	/* FIXME: multipliers only act as pass-thru element for now */
+	multiplier = snd_usb_find_clock_multiplier(host_iface, entity_id);
+	if (multiplier)
+		return __uac_clock_find_source(chip, host_iface,
+					       multiplier->bCSourceID, visited);
+
+	return -EINVAL;
+}
+
+int snd_usb_clock_find_source(struct snd_usb_audio *chip,
+			      struct usb_host_interface *host_iface,
+			      int entity_id)
+{
+	DECLARE_BITMAP(visited, 256);
+	memset(visited, 0, sizeof(visited));
+	return __uac_clock_find_source(chip, host_iface, entity_id, visited);
+}
+
+static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
+			      struct usb_host_interface *alts,
+			      struct audioformat *fmt, int rate)
+{
+	struct usb_device *dev = chip->dev;
+	unsigned int ep;
+	unsigned char data[3];
+	int err, crate;
+
+	ep = get_endpoint(alts, 0)->bEndpointAddress;
+
+	/* if endpoint doesn't have sampling rate control, bail out */
+	if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE)) {
+		snd_printk(KERN_WARNING "%d:%d:%d: endpoint lacks sample rate attribute bit, cannot set.\n",
+				   dev->devnum, iface, fmt->altsetting);
+		return 0;
+	}
+
+	data[0] = rate;
+	data[1] = rate >> 8;
+	data[2] = rate >> 16;
+	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
+				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
+				   UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
+				   data, sizeof(data), 1000)) < 0) {
+		snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d to ep %#x\n",
+			   dev->devnum, iface, fmt->altsetting, rate, ep);
+		return err;
+	}
+
+	if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
+				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
+				   UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
+				   data, sizeof(data), 1000)) < 0) {
+		snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq at ep %#x\n",
+			   dev->devnum, iface, fmt->altsetting, ep);
+		return 0; /* some devices don't support reading */
+	}
+
+	crate = data[0] | (data[1] << 8) | (data[2] << 16);
+	if (crate != rate) {
+		snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", crate, rate);
+		// runtime->rate = crate;
+	}
+
+	return 0;
+}
+
+static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
+			      struct usb_host_interface *alts,
+			      struct audioformat *fmt, int rate)
+{
+	struct usb_device *dev = chip->dev;
+	unsigned char data[4];
+	int err, crate;
+	int clock = snd_usb_clock_find_source(chip, chip->ctrl_intf, fmt->clock);
+
+	if (clock < 0)
+		return clock;
+
+	if (!uac_clock_source_is_valid(chip, clock)) {
+		snd_printk(KERN_ERR "%d:%d:%d: clock source %d is not valid, cannot use\n",
+			   dev->devnum, iface, fmt->altsetting, clock);
+		return -ENXIO;
+	}
+
+	data[0] = rate;
+	data[1] = rate >> 8;
+	data[2] = rate >> 16;
+	data[3] = rate >> 24;
+	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
+				   USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
+				   UAC2_CS_CONTROL_SAM_FREQ << 8, clock << 8,
+				   data, sizeof(data), 1000)) < 0) {
+		snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d (v2)\n",
+			   dev->devnum, iface, fmt->altsetting, rate);
+		return err;
+	}
+
+	if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
+				   USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
+				   UAC2_CS_CONTROL_SAM_FREQ << 8, clock << 8,
+				   data, sizeof(data), 1000)) < 0) {
+		snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq (v2)\n",
+			   dev->devnum, iface, fmt->altsetting);
+		return err;
+	}
+
+	crate = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
+	if (crate != rate)
+		snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", crate, rate);
+
+	return 0;
+}
+
+int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
+			     struct usb_host_interface *alts,
+			     struct audioformat *fmt, int rate)
+{
+	struct usb_interface_descriptor *altsd = get_iface_desc(alts);
+
+	switch (altsd->bInterfaceProtocol) {
+	case UAC_VERSION_1:
+		return set_sample_rate_v1(chip, iface, alts, fmt, rate);
+
+	case UAC_VERSION_2:
+		return set_sample_rate_v2(chip, iface, alts, fmt, rate);
+	}
+
+	return -EINVAL;
+}
+