diff options
Diffstat (limited to 'sound/usb')
| -rw-r--r-- | sound/usb/pcm.c | 89 |
1 files changed, 87 insertions, 2 deletions
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index cec6e91afea2..6a460225f2e3 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -659,6 +659,9 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream) #define hwc_debug(fmt, args...) do { } while(0) #endif +#define MAX_BUFFER_BYTES (1024 * 1024) +#define MAX_PERIOD_BYTES (512 * 1024) + static const struct snd_pcm_hardware snd_usb_hardware = { .info = SNDRV_PCM_INFO_MMAP | @@ -669,9 +672,9 @@ static const struct snd_pcm_hardware snd_usb_hardware = SNDRV_PCM_INFO_PAUSE, .channels_min = 1, .channels_max = 256, - .buffer_bytes_max = 1024 * 1024, + .buffer_bytes_max = MAX_BUFFER_BYTES, .period_bytes_min = 64, - .period_bytes_max = 512 * 1024, + .period_bytes_max = MAX_PERIOD_BYTES, .periods_min = 2, .periods_max = 1024, }; @@ -971,6 +974,78 @@ static int hw_rule_periods_implicit_fb(struct snd_pcm_hw_params *params, ep->cur_buffer_periods); } +/* get the adjusted max buffer (or period) bytes that can fit with the + * paired format for implicit fb + */ +static unsigned int +get_adjusted_max_bytes(struct snd_usb_substream *subs, + struct snd_usb_substream *pair, + struct snd_pcm_hw_params *params, + unsigned int max_bytes, + bool reverse_map) +{ + const struct audioformat *fp, *pp; + unsigned int rmax = 0, r; + + list_for_each_entry(fp, &subs->fmt_list, list) { + if (!fp->implicit_fb) + continue; + if (!reverse_map && + !hw_check_valid_format(subs, params, fp)) + continue; + list_for_each_entry(pp, &pair->fmt_list, list) { + if (pp->iface != fp->sync_iface || + pp->altsetting != fp->sync_altsetting || + pp->ep_idx != fp->sync_ep_idx) + continue; + if (reverse_map && + !hw_check_valid_format(pair, params, pp)) + break; + if (!reverse_map && pp->channels > fp->channels) + r = max_bytes * fp->channels / pp->channels; + else if (reverse_map && pp->channels < fp->channels) + r = max_bytes * pp->channels / fp->channels; + else + r = max_bytes; + rmax = max(rmax, r); + break; + } + } + return rmax; +} + +/* Reduce the period or buffer bytes depending on the paired substream; + * when a paired configuration for implicit fb has a higher number of channels, + * we need to reduce the max size accordingly, otherwise it may become unusable + */ +static int hw_rule_bytes_implicit_fb(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) +{ + struct snd_usb_substream *subs = rule->private; + struct snd_usb_substream *pair; + struct snd_interval *it; + unsigned int max_bytes; + unsigned int rmax; + + pair = &subs->stream->substream[!subs->direction]; + if (!pair->ep_num) + return 0; + + if (rule->var == SNDRV_PCM_HW_PARAM_PERIOD_BYTES) + max_bytes = MAX_PERIOD_BYTES; + else + max_bytes = MAX_BUFFER_BYTES; + + rmax = get_adjusted_max_bytes(subs, pair, params, max_bytes, false); + if (!rmax) + rmax = get_adjusted_max_bytes(pair, subs, params, max_bytes, true); + if (!rmax) + return 0; + + it = hw_param_interval(params, rule->var); + return apply_hw_params_minmax(it, 0, rmax); +} + /* * set up the runtime hardware information. */ @@ -1085,6 +1160,16 @@ static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substre SNDRV_PCM_HW_PARAM_PERIODS, -1); if (err < 0) return err; + err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, + hw_rule_bytes_implicit_fb, subs, + SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1); + if (err < 0) + return err; + err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, + hw_rule_bytes_implicit_fb, subs, + SNDRV_PCM_HW_PARAM_PERIOD_BYTES, -1); + if (err < 0) + return err; list_for_each_entry(fp, &subs->fmt_list, list) { if (fp->implicit_fb) { |