1 files changed, 311 insertions, 0 deletions

diff --git a/sound/usb/clock.c b/sound/usb/clock.c
new file mode 100644
index 000000000000..b7aadd614c70
--- /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;
+}
+