diff --git a/sound/usb/clock.c b/sound/usb/clock.c index a694e1c42fdf..ae35e7d22e73 100644 --- a/sound/usb/clock.c +++ b/sound/usb/clock.c @@ -347,6 +347,8 @@ static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface, __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) @@ -354,20 +356,33 @@ static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface, prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock); - data = cpu_to_le32(rate); - 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))) < 0) { - snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d (v2): err %d\n", - dev->devnum, iface, fmt->altsetting, rate, err); - return err; + 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) { + snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d (v2): err %d\n", + dev->devnum, iface, fmt->altsetting, rate, err); + return err; + } + + cur_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock); + } else { + cur_rate = prev_rate; } - cur_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock); - if (cur_rate != rate) { + if (!writeable) { + snd_printk(KERN_WARNING + "%d:%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n", + dev->devnum, iface, fmt->altsetting, rate, cur_rate); + return -ENXIO; + } snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", cur_rate, rate);