diff options
Diffstat (limited to 'kernel/sound/usb/clock.c')
| -rw-r--r-- | kernel/sound/usb/clock.c | 427 |
1 files changed, 427 insertions, 0 deletions
diff --git a/kernel/sound/usb/clock.c b/kernel/sound/usb/clock.c new file mode 100644 index 000000000..2ed260b10 --- /dev/null +++ b/kernel/sound/usb/clock.c @@ -0,0 +1,427 @@ +/* + * 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/string.h> +#include <linux/usb.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 "usbaudio.h" +#include "card.h" +#include "helper.h" +#include "clock.h" +#include "quirks.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)); + + if (ret < 0) + return ret; + + return buf; +} + +static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id, + unsigned char pin) +{ + int ret; + + ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), + UAC2_CS_CUR, + USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT, + UAC2_CX_CLOCK_SELECTOR << 8, + snd_usb_ctrl_intf(chip) | (selector_id << 8), + &pin, sizeof(pin)); + if (ret < 0) + return ret; + + if (ret != sizeof(pin)) { + usb_audio_err(chip, + "setting selector (id %d) unexpected length %d\n", + selector_id, ret); + return -EINVAL; + } + + ret = uac_clock_selector_get_val(chip, selector_id); + if (ret < 0) + return ret; + + if (ret != pin) { + usb_audio_err(chip, + "setting selector (id %d) to %x failed (current: %d)\n", + selector_id, pin, ret); + return -EINVAL; + } + + return ret; +} + +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; + struct uac_clock_source_descriptor *cs_desc = + snd_usb_find_clock_source(chip->ctrl_intf, source_id); + + if (!cs_desc) + return 0; + + /* If a clock source can't tell us whether it's valid, we assume it is */ + if (!uac2_control_is_readable(cs_desc->bmControls, + UAC2_CS_CONTROL_CLOCK_VALID - 1)) + return 1; + + 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)); + + if (err < 0) { + dev_warn(&dev->dev, + "%s(): cannot get clock validity for id %d\n", + __func__, source_id); + return 0; + } + + return !!data; +} + +static int __uac_clock_find_source(struct snd_usb_audio *chip, + int entity_id, unsigned long *visited, + bool validate) +{ + 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)) { + usb_audio_warn(chip, + "%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(chip->ctrl_intf, entity_id); + if (source) { + entity_id = source->bClockID; + if (validate && !uac_clock_source_is_valid(chip, entity_id)) { + usb_audio_err(chip, + "clock source %d is not valid, cannot use\n", + entity_id); + return -ENXIO; + } + return entity_id; + } + + selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id); + if (selector) { + int ret, i, cur; + + /* 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; + + /* Selector values are one-based */ + + if (ret > selector->bNrInPins || ret < 1) { + usb_audio_err(chip, + "%s(): selector reported illegal value, id %d, ret %d\n", + __func__, selector->bClockID, ret); + + return -EINVAL; + } + + cur = ret; + ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1], + visited, validate); + if (!validate || ret > 0 || !chip->autoclock) + return ret; + + /* The current clock source is invalid, try others. */ + for (i = 1; i <= selector->bNrInPins; i++) { + int err; + + if (i == cur) + continue; + + ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1], + visited, true); + if (ret < 0) + continue; + + err = uac_clock_selector_set_val(chip, entity_id, i); + if (err < 0) + continue; + + usb_audio_info(chip, + "found and selected valid clock source %d\n", + ret); + return ret; + } + + return -ENXIO; + } + + /* FIXME: multipliers only act as pass-thru element for now */ + multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id); + if (multiplier) + return __uac_clock_find_source(chip, multiplier->bCSourceID, + visited, validate); + + return -EINVAL; +} + +/* + * For all kinds of sample rate settings and other device queries, + * the clock source (end-leaf) must be used. However, clock selectors, + * clock multipliers and sample rate converters may be specified as + * clock source input to terminal. This functions walks the clock path + * to its end and tries to find the source. + * + * The 'visited' bitfield is used internally to detect recursive loops. + * + * Returns the clock source UnitID (>=0) on success, or an error. + */ +int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id, + bool validate) +{ + DECLARE_BITMAP(visited, 256); + memset(visited, 0, sizeof(visited)); + return __uac_clock_find_source(chip, entity_id, visited, validate); +} + +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)) + 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))) < 0) { + dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n", + iface, fmt->altsetting, rate, ep); + return err; + } + + /* Don't check the sample rate for devices which we know don't + * support reading */ + if (snd_usb_get_sample_rate_quirk(chip)) + return 0; + + 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))) < 0) { + dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n", + iface, fmt->altsetting, ep); + return 0; /* some devices don't support reading */ + } + + crate = data[0] | (data[1] << 8) | (data[2] << 16); + if (crate != rate) { + dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate); + // runtime->rate = crate; + } + + return 0; +} + +static int get_sample_rate_v2(struct snd_usb_audio *chip, int iface, + int altsetting, int clock) +{ + struct usb_device *dev = chip->dev; + __le32 data; + int err; + + 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)); + if (err < 0) { + dev_warn(&dev->dev, "%d:%d: cannot get freq (v2): err %d\n", + iface, altsetting, err); + return 0; + } + + return le32_to_cpu(data); +} + +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; + __le32 data; + int err, cur_rate, prev_rate; + int clock; + bool writeable; + struct uac_clock_source_descriptor *cs_desc; + + clock = snd_usb_clock_find_source(chip, fmt->clock, true); + if (clock < 0) + return clock; + + prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock); + if (prev_rate == rate) + return 0; + + cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock); + writeable = uac2_control_is_writeable(cs_desc->bmControls, UAC2_CS_CONTROL_SAM_FREQ - 1); + if (writeable) { + data = cpu_to_le32(rate); + 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)); + if (err < 0) { + usb_audio_err(chip, + "%d:%d: cannot set freq %d (v2): err %d\n", + iface, fmt->altsetting, rate, err); + return err; + } + + cur_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock); + } else { + cur_rate = prev_rate; + } + + if (cur_rate != rate) { + if (!writeable) { + usb_audio_warn(chip, + "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n", + iface, fmt->altsetting, rate, cur_rate); + return -ENXIO; + } + usb_audio_dbg(chip, + "current rate %d is different from the runtime rate %d\n", + cur_rate, rate); + } + + /* Some devices doesn't respond to sample rate changes while the + * interface is active. */ + if (rate != prev_rate) { + usb_set_interface(dev, iface, 0); + snd_usb_set_interface_quirk(dev); + usb_set_interface(dev, iface, fmt->altsetting); + snd_usb_set_interface_quirk(dev); + } + + 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) +{ + switch (fmt->protocol) { + case UAC_VERSION_1: + default: + return set_sample_rate_v1(chip, iface, alts, fmt, rate); + + case UAC_VERSION_2: + return set_sample_rate_v2(chip, iface, alts, fmt, rate); + } +} + |