From 66890d53130d90df4572987b2ebcad05595f76c7 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Tue, 4 Sep 2018 17:58:46 +0200
Subject: [PATCH] staging: bcm2835-audio: Add 10ms period constraint
Git-commit: 66890d53130d90df4572987b2ebcad05595f76c7
Patch-mainline: v4.20-rc1
References: FATE#324827
It seems that the resolution of vc04 callback is in 10 msec; i.e. the
minimal period size is also 10 msec.
This patch adds the corresponding hw constraint.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
@@ -145,6 +145,11 @@ static int snd_bcm2835_playback_open_gen
SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
16);
+ /* position update is in 10ms order */
+ snd_pcm_hw_constraint_minmax(runtime,
+ SNDRV_PCM_HW_PARAM_PERIOD_TIME,
+ 10 * 1000, UINT_MAX);
+
chip->alsa_stream[idx] = alsa_stream;
chip->opened |= (1 << idx);