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-rw-r--r--sound/usb/clock.c315
1 files changed, 315 insertions, 0 deletions
diff --git a/sound/usb/clock.c b/sound/usb/clock.c
new file mode 100644
index 00000000000..b5855114667
--- /dev/null
+++ b/sound/usb/clock.c
@@ -0,0 +1,315 @@
+/*
+ * 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,
+ snd_usb_ctrl_intf(chip) | (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,
+ snd_usb_ctrl_intf(chip) | (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,
+ snd_usb_ctrl_intf(chip) | (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,
+ snd_usb_ctrl_intf(chip) | (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;
+}
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 04:11:14 +0000