ALSA: usb-audio: Simplify rate_min/max and rates set up

There are multiple places in format.c performing the similar code for
setting the rate_min, rate_max and rates fields.  This patch unifies
those in a helper function and calls it at the end of the parser phase
so that all rate_table entries have been already determined.

No functional changes, just a minor code refactoring.

Tested-by: Keith Milner <kamilner@superlative.org>
Tested-by: Dylan Robinson <dylan_robinson@motu.com>
Link: https://lore.kernel.org/r/20201123085347.19667-33-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/format.c b/sound/usb/format.c
index 7641716..93459ba 100644 (file)
--- a/sound/usb/format.c
+++ b/sound/usb/format.c
@@ -164,6 +164,23 @@ static int set_fixed_rate(struct audioformat *fp, int rate, int rate_bits)
        return 0;
 }
 
+/* set up rate_min, rate_max and rates from the rate table */
+static void set_rate_table_min_max(struct audioformat *fp)
+{
+       unsigned int rate;
+       int i;
+
+       fp->rate_min = INT_MAX;
+       fp->rate_max = 0;
+       fp->rates = 0;
+       for (i = 0; i < fp->nr_rates; i++) {
+               rate = fp->rate_table[i];
+               fp->rate_min = min(fp->rate_min, rate);
+               fp->rate_max = max(fp->rate_max, rate);
+               fp->rates |= snd_pcm_rate_to_rate_bit(rate);
+       }
+}
+
 /*
  * parse the format descriptor and stores the possible sample rates
  * on the audioformat table (audio class v1).
@@ -198,7 +215,6 @@ static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audiof
                        return -ENOMEM;
 
                fp->nr_rates = 0;
-               fp->rate_min = fp->rate_max = 0;
                for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
                        unsigned int rate = combine_triple(&fmt[idx]);
                        if (!rate)
@@ -217,13 +233,7 @@ static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audiof
                             chip->usb_id == USB_ID(0x041e, 0x4068)))
                                rate = 8000;
 
-                       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++;
+                       fp->rate_table[fp->nr_rates++] = rate;
                }
                if (!fp->nr_rates) {
                        usb_audio_info(chip,
@@ -231,6 +241,7 @@ static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audiof
                                       fp->iface, fp->altsetting);
                        return -EINVAL;
                }
+               set_rate_table_min_max(fp);
        } else {
                /* continuous rates */
                fp->rates = SNDRV_PCM_RATE_CONTINUOUS;
@@ -336,8 +347,6 @@ static int parse_uac2_sample_rate_range(struct snd_usb_audio *chip,
 {
        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]);
@@ -373,12 +382,6 @@ static int parse_uac2_sample_rate_range(struct snd_usb_audio *chip,
 
                        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++;
                        if (nr_rates >= MAX_NR_RATES) {
                                usb_audio_err(chip, "invalid uac2 rates\n");
@@ -459,9 +462,6 @@ static int validate_sample_rate_table_v2v3(struct snd_usb_audio *chip,
        struct usb_device *dev = chip->dev;
        unsigned int *table;
        unsigned int nr_rates;
-       unsigned int rate_min = 0x7fffffff;
-       unsigned int rate_max = 0;
-       unsigned int rates = 0;
        int i, err;
 
        table = kcalloc(fp->nr_rates, sizeof(*table), GFP_KERNEL);
@@ -478,14 +478,8 @@ static int validate_sample_rate_table_v2v3(struct snd_usb_audio *chip,
                if (err < 0)
                        continue;
 
-               if (check_valid_altsetting_v2v3(chip, fp->iface, fp->altsetting)) {
+               if (check_valid_altsetting_v2v3(chip, fp->iface, fp->altsetting))
                        table[nr_rates++] = fp->rate_table[i];
-                       if (rate_min > fp->rate_table[i])
-                               rate_min = fp->rate_table[i];
-                       if (rate_max < fp->rate_table[i])
-                               rate_max = fp->rate_table[i];
-                       rates |= snd_pcm_rate_to_rate_bit(fp->rate_table[i]);
-               }
        }
 
        if (!nr_rates) {
@@ -503,9 +497,6 @@ static int validate_sample_rate_table_v2v3(struct snd_usb_audio *chip,
        kfree(fp->rate_table);
        fp->rate_table = table;
        fp->nr_rates = nr_rates;
-       fp->rate_min = rate_min;
-       fp->rate_max = rate_max;
-       fp->rates = rates;
        return 0;
 }
 
@@ -602,6 +593,10 @@ static int parse_audio_format_rates_v2v3(struct snd_usb_audio *chip,
        parse_uac2_sample_rate_range(chip, fp, nr_triplets, data);
 
        ret = validate_sample_rate_table_v2v3(chip, fp, clock);
+       if (ret < 0)
+               goto err_free;
+
+       set_rate_table_min_max(fp);
 
 err_free:
        kfree(data);