A device may report its supported sample rates in ranges rather than in discrete triplets. The code used to only parse the MIN field instead of properly paying attention to the MAX and RES values.

Also, handle RES values of 1 corrently and announce a continous sample rate range in this case.

Signed-off-by: Daniel Mack daniel@caiaq.de Reported-by: Alex Lee alexlee188@gmail.com --- sound/usb/format.c | 89 +++++++++++++++++++++++++++++++++++++++++---------- 1 files changed, 71 insertions(+), 18 deletions(-)

diff --git a/sound/usb/format.c b/sound/usb/format.c index 8eccf17..7a54a0a 100644 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -206,6 +206,57 @@ static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audiof }

/* + * Helper function to walk the array of sample rate triplets reported by + * the device. The problem is that we need to parse whole array first to + * get to know how many sample rates we have to expect. + * Then fp->rate_table can be allocated and filled. + */ +static int parse_uac2_sample_rate_range(struct audioformat *fp, int nr_triplets, + const unsigned char *data) +{ + int i, nr_rates = 0; + + fp->rates = fp->rate_min = fp->rate_max = 0; + + for (i = 0; i < nr_triplets; i++) { + int min = combine_quad(&data[2 + 12 * i]); + int max = combine_quad(&data[6 + 12 * i]); + int res = combine_quad(&data[10 + 12 * i]); + int rate; + + if ((max < 0) || (min < 0) || (res < 0) || (max < min)) + continue; + + /* + * for ranges with res == 1, we want a continuous sample + * rate range, so this function should return 0. + */ + if (res == 1) { + fp->rates = SNDRV_PCM_RATE_CONTINUOUS; + return 0; + } + + for (rate = min; rate <= max; rate += res) { + if (fp->rate_table) + fp->rate_table[nr_rates] = rate; + if (!fp->rate_min || rate < fp->rate_min) + fp->rate_min = rate; + if (!fp->rate_max || rate > fp->rate_max) + fp->rate_max = rate; + fp->rates |= snd_pcm_rate_to_rate_bit(rate); + + nr_rates++; + + /* avoid endless loop */ + if (res == 0) + break; + } + } + + return nr_rates; +} + +/* * parse the format descriptor and stores the possible sample rates * on the audioformat table (audio class v2). */ @@ -215,7 +266,7 @@ static int parse_audio_format_rates_v2(struct snd_usb_audio *chip, { struct usb_device *dev = chip->dev; unsigned char tmp[2], *data; - int i, nr_rates, data_size, ret = 0; + int nr_triplets, data_size, ret = 0; int clock = snd_usb_clock_find_source(chip, chip->ctrl_intf, fp->clock);

if (clock < 0) { @@ -237,8 +288,8 @@ static int parse_audio_format_rates_v2(struct snd_usb_audio *chip, goto err; }

- nr_rates = (tmp[1] << 8) | tmp[0]; - data_size = 2 + 12 * nr_rates; + nr_triplets = (tmp[1] << 8) | tmp[0]; + data_size = 2 + 12 * nr_triplets; data = kzalloc(data_size, GFP_KERNEL); if (!data) { ret = -ENOMEM; @@ -259,26 +310,28 @@ static int parse_audio_format_rates_v2(struct snd_usb_audio *chip, goto err_free; }

- fp->rate_table = kmalloc(sizeof(int) * nr_rates, GFP_KERNEL); + /* Call the triplet parser, and make sure fp->rate_table is NULL. + * We just use the return value to know how many sample rates we + * will have to deal with. */ + kfree(fp->rate_table); + fp->rate_table = NULL; + fp->nr_rates = parse_uac2_sample_rate_range(fp, nr_triplets, data); + + if (fp->nr_rates == 0) { + /* SNDRV_PCM_RATE_CONTINUOUS */ + err = 0; + goto err_free; + } + + fp->rate_table = kmalloc(sizeof(int) * fp->nr_rates, GFP_KERNEL); if (!fp->rate_table) { ret = -ENOMEM; goto err_free; }

- fp->nr_rates = 0; - fp->rate_min = fp->rate_max = 0; - - for (i = 0; i < nr_rates; i++) { - int rate = combine_quad(&data[2 + 12 * i]); - - fp->rate_table[fp->nr_rates] = rate; - if (!fp->rate_min || rate < fp->rate_min) - fp->rate_min = rate; - if (!fp->rate_max || rate > fp->rate_max) - fp->rate_max = rate; - fp->rates |= snd_pcm_rate_to_rate_bit(rate); - fp->nr_rates++; - } + /* Call the triplet parser again, but this time, fp->rate_table is + * allocated, so the rates will be stored */ + parse_uac2_sample_rate_range(fp, nr_triplets, data);

err_free: kfree(data);

For RANGE requests, we should only query as much bytes as we're in fact interested in.

For CUR requests, we shouldn't confuse the firmware with an overlong request but just ask for 2 bytes.

This might need fixing in the future as it's not entirely clear when to dispatch 1-byte, 2-byte and 4-byte request blocks. For now, we assume everything is coded in 16bit - this works for all firmware implementations I've seen.

Signed-off-by: Daniel Mack daniel@caiaq.de Reported-by: Alex Lee alexlee188@gmail.com --- sound/usb/mixer.c | 19 ++++++++++++++----- 1 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index a060d00..6939d0f 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -297,20 +297,27 @@ static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int v

static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret) { - unsigned char buf[14]; /* enough space for one range of 4 bytes */ + unsigned char buf[2 + 3*sizeof(__u16)]; /* enough space for one range */ unsigned char *val; - int ret; + int ret, size; __u8 bRequest;

- bRequest = (request == UAC_GET_CUR) ? - UAC2_CS_CUR : UAC2_CS_RANGE; + if (request == UAC_GET_CUR) { + bRequest = UAC2_CS_CUR; + size = sizeof(__u16); + } else { + bRequest = UAC2_CS_RANGE; + size = sizeof(buf); + } + + memset(buf, 0, sizeof(buf));

ret = snd_usb_ctl_msg(cval->mixer->chip->dev, usb_rcvctrlpipe(cval->mixer->chip->dev, 0), bRequest, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN, validx, cval->mixer->ctrlif | (cval->id << 8), - buf, sizeof(buf), 1000); + buf, size, 1000);

if (ret < 0) { snd_printk(KERN_ERR "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n", @@ -318,6 +325,8 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v return ret; }

+ /* FIXME: how should we handle multiple triplets here? */ + switch (request) { case UAC_GET_CUR: val = buf;