sound: usb-audio: remove check_hw_params_convention()

This removes the check_hw_params_convention() function because
1) it is not necessary, as the hw_rule_* functions also work correctly
   (i.e., as no-ops) when the device supports all combinations of the
   audio format parameters; and
2) it would become too complex when adding a fourth altsetting-dependent
   hardware parameter, as this would require another three loops to
   check dependecies with rate/channels/format.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 19 insertions, 116 deletions

diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c
index 175c7d1da5cf..b7fa0b0b713d 100644
--- a/sound/usb/usbaudio.c
+++ b/sound/usb/usbaudio.c
@@ -1736,97 +1736,6 @@ static int hw_rule_format(struct snd_pcm_hw_params *params,
         return changed;
 }
 
-#define MAX_MASK        64
-
-/*
- * check whether the registered audio formats need special hw-constraints
- */
-static int check_hw_params_convention(struct snd_usb_substream *subs)
-{
-        int i;
-        u32 *channels;
-        u32 *rates;
-        u32 cmaster, rmaster;
-        u32 rate_min = 0, rate_max = 0;
-        struct list_head *p;
-        int err = 1;
-
-        channels = kcalloc(MAX_MASK, sizeof(u32), GFP_KERNEL);
-        rates = kcalloc(MAX_MASK, sizeof(u32), GFP_KERNEL);
-        if (!channels || !rates) {
-                err = -ENOMEM;
-                goto __out;
-        }
-
-        list_for_each(p, &subs->fmt_list) {
-                struct audioformat *f;
-                f = list_entry(p, struct audioformat, list);
-                /* unconventional channels? */
-                if (f->channels > 32)
-                        goto __out;
-                /* continuous rate min/max matches? */
-                if (f->rates & SNDRV_PCM_RATE_CONTINUOUS) {
-                        if (rate_min && f->rate_min != rate_min)
-                                goto __out;
-                        if (rate_max && f->rate_max != rate_max)
-                                goto __out;
-                        rate_min = f->rate_min;
-                        rate_max = f->rate_max;
-                }
-                /* combination of continuous rates and fixed rates? */
-                if (rates[f->format] & SNDRV_PCM_RATE_CONTINUOUS) {
-                        if (f->rates != rates[f->format])
-                                goto __out;
-                }
-                if (f->rates & SNDRV_PCM_RATE_CONTINUOUS) {
-                        if (rates[f->format] && rates[f->format] != f->rates)
-                                goto __out;
-                }
-                channels[f->format] |= 1 << (f->channels - 1);
-                rates[f->format] |= f->rates;
-                /* needs knot? */
-                if (f->rates & SNDRV_PCM_RATE_KNOT)
-                        goto __out;
-        }
-        /* check whether channels and rates match for all formats */
-        cmaster = rmaster = 0;
-        for (i = 0; i < MAX_MASK; i++) {
-                if (cmaster != channels[i] && cmaster && channels[i])
-                        goto __out;
-                if (rmaster != rates[i] && rmaster && rates[i])
-                        goto __out;
-                if (channels[i])
-                        cmaster = channels[i];
-                if (rates[i])
-                        rmaster = rates[i];
-        }
-        /* check whether channels match for all distinct rates */
-        memset(channels, 0, MAX_MASK * sizeof(u32));
-        list_for_each(p, &subs->fmt_list) {
-                struct audioformat *f;
-                f = list_entry(p, struct audioformat, list);
-                if (f->rates & SNDRV_PCM_RATE_CONTINUOUS)
-                        continue;
-                for (i = 0; i < 32; i++) {
-                        if (f->rates & (1 << i))
-                                channels[i] |= 1 << (f->channels - 1);
-                }
-        }
-        cmaster = 0;
-        for (i = 0; i < 32; i++) {
-                if (cmaster != channels[i] && cmaster && channels[i])
-                        goto __out;
-                if (channels[i])
-                        cmaster = channels[i];
-        }
-        err = 0;
-
- __out:
-        kfree(channels);
-        kfree(rates);
-        return err;
-}
-
 /*
  *  If the device supports unusual bit rates, does the request meet these?
  */
@@ -1909,32 +1818,26 @@ static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substre
                                      1000,
                                      /*(nrpacks * MAX_URBS) * 1000*/ UINT_MAX);
 
-        err = check_hw_params_convention(subs);
-        if (err < 0)
+        if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+                                       hw_rule_rate, subs,
+                                       SNDRV_PCM_HW_PARAM_FORMAT,
+                                       SNDRV_PCM_HW_PARAM_CHANNELS,
+                                       -1)) < 0)
+                return err;
+        if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
+                                       hw_rule_channels, subs,
+                                       SNDRV_PCM_HW_PARAM_FORMAT,
+                                       SNDRV_PCM_HW_PARAM_RATE,
+                                       -1)) < 0)
+                return err;
+        if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
+                                       hw_rule_format, subs,
+                                       SNDRV_PCM_HW_PARAM_RATE,
+                                       SNDRV_PCM_HW_PARAM_CHANNELS,
+                                       -1)) < 0)
+                return err;
+        if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
                 return err;
-        else if (err) {
-                hwc_debug("setting extra hw constraints...\n");
-                if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
-                                               hw_rule_rate, subs,
-                                               SNDRV_PCM_HW_PARAM_FORMAT,
-                                               SNDRV_PCM_HW_PARAM_CHANNELS,
-                                               -1)) < 0)
-                        return err;
-                if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
-                                               hw_rule_channels, subs,
-                                               SNDRV_PCM_HW_PARAM_FORMAT,
-                                               SNDRV_PCM_HW_PARAM_RATE,
-                                               -1)) < 0)
-                        return err;
-                if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
-                                               hw_rule_format, subs,
-                                               SNDRV_PCM_HW_PARAM_RATE,
-                                               SNDRV_PCM_HW_PARAM_CHANNELS,
-                                               -1)) < 0)
-                        return err;
-                if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
-                        return err;
-        }
         return 0;
 }