[PATCH 1/6] ALSA: fireface: fix configuration error for nominal sampling transfer frequency

Takashi Sakamoto o-takashi at sakamocchi.jp
Sun May 10 09:42:56 CEST 2020


128000 and 192000 are congruence modulo 32000, thus it's wrong to
distinguish them as multiple of 32000 and 48000 by modulo 32000 at
first.

Additionally, used condition statement to detect quadruple speed can
cause missing bit flag.

Furthermore, counter to ensure the configuration is wrong and it
causes false positive.

This commit fixes the above three bugs.

Cc: <stable at vger.kernel.org>
Fixes: 60aec494b389 ("ALSA: fireface: support allocate_resources operation in latter protocol")
Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/firewire/fireface/ff-protocol-latter.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/sound/firewire/fireface/ff-protocol-latter.c b/sound/firewire/fireface/ff-protocol-latter.c
index 0e4c3a9ed5e4..76ae568489ef 100644
--- a/sound/firewire/fireface/ff-protocol-latter.c
+++ b/sound/firewire/fireface/ff-protocol-latter.c
@@ -107,18 +107,18 @@ static int latter_allocate_resources(struct snd_ff *ff, unsigned int rate)
 	int err;
 
 	// Set the number of data blocks transferred in a second.
-	if (rate % 32000 == 0)
-		code = 0x00;
+	if (rate % 48000 == 0)
+		code = 0x04;
 	else if (rate % 44100 == 0)
 		code = 0x02;
-	else if (rate % 48000 == 0)
-		code = 0x04;
+	else if (rate % 32000 == 0)
+		code = 0x00;
 	else
 		return -EINVAL;
 
 	if (rate >= 64000 && rate < 128000)
 		code |= 0x08;
-	else if (rate >= 128000 && rate < 192000)
+	else if (rate >= 128000)
 		code |= 0x10;
 
 	reg = cpu_to_le32(code);
@@ -140,7 +140,7 @@ static int latter_allocate_resources(struct snd_ff *ff, unsigned int rate)
 		if (curr_rate == rate)
 			break;
 	}
-	if (count == 10)
+	if (count > 10)
 		return -ETIMEDOUT;
 
 	for (i = 0; i < ARRAY_SIZE(amdtp_rate_table); ++i) {
-- 
2.25.1



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