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)) 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), 1000); if (err < 0) { snd_printk(KERN_WARNING "%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) { 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)) { #ifdef CONFIG_DEBUG_PRINTK snd_printk(KERN_WARNING "%s(): recursive clock topology detected, id %d.\n", __func__, entity_id); #else ; #endif 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) return source->bClockID; selector = snd_usb_find_clock_selector(chip->ctrl_intf, 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; /* Selector values are one-based */ 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, selector->baCSourceID[ret-1], visited); } /* 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); return -EINVAL; }
static int __uac_clock_find_source(struct snd_usb_audio *chip, 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; } source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id); if (source) return source->bClockID; selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id); if (selector) { int ret; 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, selector->baCSourceID[ret-1], visited); } multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id); if (multiplier) return __uac_clock_find_source(chip, multiplier->bCSourceID, visited); return -EINVAL; }
static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int protocol, int source_id) { int err; unsigned char data; struct usb_device *dev = chip->dev; u32 bmControls; if (protocol == UAC_VERSION_3) { struct uac3_clock_source_descriptor *cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id); if (!cs_desc) return 0; bmControls = le32_to_cpu(cs_desc->bmControls); } else { /* UAC_VERSION_1/2 */ struct uac_clock_source_descriptor *cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, source_id); if (!cs_desc) return 0; bmControls = cs_desc->bmControls; } /* If a clock source can't tell us whether it's valid, we assume it is */ if (!uac_v2v3_control_is_readable(bmControls, UAC2_CS_CONTROL_CLOCK_VALID)) 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 set_sample_rate_v2v3(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; u32 bmControls; /* First, try to find a valid clock. This may trigger * automatic clock selection if the current clock is not * valid. */ clock = snd_usb_clock_find_source(chip, fmt->protocol, fmt->clock, true); if (clock < 0) { /* We did not find a valid clock, but that might be * because the current sample rate does not match an * external clock source. Try again without validation * and we will do another validation after setting the * rate. */ clock = snd_usb_clock_find_source(chip, fmt->protocol, fmt->clock, false); if (clock < 0) return clock; } prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock); if (prev_rate == rate) goto validation; if (fmt->protocol == UAC_VERSION_3) { struct uac3_clock_source_descriptor *cs_desc; cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock); bmControls = le32_to_cpu(cs_desc->bmControls); } else { struct uac_clock_source_descriptor *cs_desc; cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock); bmControls = cs_desc->bmControls; } writeable = uac_v2v3_control_is_writeable(bmControls, UAC2_CS_CONTROL_SAM_FREQ); 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/v3): err %d\n", iface, fmt->altsetting, rate, err); return err; } cur_rate = get_sample_rate_v2v3(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); } validation: /* validate clock after rate change */ if (!uac_clock_source_is_valid(chip, fmt->protocol, clock)) return -ENXIO; return 0; }
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, UAC_VERSION_2, 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; }