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ALSA: hda/tas2781: Add hardware stabilization delay during firmware load retries

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During runtime resume transitions, loading calibration data blocks
to the tas2781 amplifier may intermittently trigger transmission
failures or block checksum mismatches (-EAGAIN) due to un-stabilized
power rails or I2C bus glitches.

The loop in tasdev_load_blk() decrements block->nr_retry and attempts
an immediate re-transmission upon receiving -EAGAIN. However, without
any inter-retry delay, all available retry slots are exhausted within
less than a microsecond—long before the hardware can physically
settle. This leads to permanent "ERROR_PRAM_CRCCHK" deadlocks and
silent speakers on modern laptops after resuming media.

Fix this cleanly by introducing a 2ms usleep_range() delay directly
inside the tasdev_load_blk() retry paths prior to each 'continue'
statement. This grants the chip sufficient time to stabilize before
the next transmission attempt without introducing unnecessary latency
on final failures.

Signed-off-by: Zeliang Li <lizeliang.linux@gmail.com>
Link: https://patch.msgid.link/20260815-master-v2-1-b4ea03c8b59e@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Zeliang Li 2026-08-15 03:45:55 +08:00 committed by Takashi Iwai
parent 19b02fecd8
commit f6635d64e7
1 changed files with 12 additions and 2 deletions
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14
sound/soc/codecs/tas2781-fmwlib.c
View File

@ -1849,16 +1849,26 @@ static int tasdev_load_blk(struct tasdevice_priv *tas_priv,
}
}
if (ret == -EAGAIN) {
if (block->nr_retry > 0)
if (block->nr_retry > 0) {
/* Give the hardware time to stabilize before
* next block re-transmission attempt.
*/
usleep_range(2000, 2500);
continue;
}
} else if (ret < 0) /*err in current device, skip it*/
break;
if (block->is_pchksum_present) {
ret = tasdev_block_chksum(tas_priv, block, chn);
if (ret == -EAGAIN) {
if (block->nr_retry > 0)
if (block->nr_retry > 0) {
/* Give the bus time to recover after
* a checksum mismatch error.
*/
usleep_range(2000, 2500);
continue;
}
} else if (ret < 0) /*err in current device, skip it*/
break;
}