The current compress offload timestamping API relies on struct
snd_compr_tstamp, whose cumulative counters like copied_total are
defined as __u32. On long-running high-resolution audio streams, these
32-bit counters can overflow, causing incorrect availability
calculations.
This patch series transitions to a 64-bit safe API to solve the problem
while maintaining perfect backward compatibility with the existing UAPI.
The pointer operation is reworked to use a new timestamp struct with
64-bit fields for the cumulative counters, named snd_compr_tstamp64.
ASoC drivers are updated to use the 64-bit structures. Corresponding
ioctls are added to expose them to user-space.
The series is structured as follows:
Patch 1: Updates the pointer op, refactors the core logic and ASoC
drivers to use it, and defines the new UAPI structs.
Patch 2: Exposes the SNDRV_COMPRESS_TSTAMP64 ioctl.
Patch 3: Exposes the corresponding SNDRV_COMPRESS_AVAIL64 ioctl.
This series has been tested on a Pixel 9 device. All compress offload
use cases, including long-running playback, were verified to work
correctly with the new 64-bit API.
Thanks,
Joris (George) Verhaegen
Signed-off-by: Joris Verhaegen <verhaegen@xxxxxxxxxx>
---
Changes in v2:
- Corrected author and Signed-off-by to be consistent (Mark Brown).
Changes in v3:
- Rework pointer op to return 64-bit timestamp, rather than adding a
parallel pointer64 op (Charles Keepax, Takashi Iwai, Vinod Koul)
- Bump the protocol version for ABI change (Takashi Iwai)
-Fix linker error on Intel Atom (lkp@xxxxxxxxx)
-Rebase on latest for-next sound tree (Takashi Iwai)
-Avoid changing return error code for ioctl (internal)
-ASoC: Replace u64 % u32 by do_div(u64, u32) (internal)
-ASoC: sprd: change current_data_offset to u64 (internal)
Changes in v4:
-Fix compiler error on Intel AVS (lkp@xxxxxxxxx)
Joris Verhaegen (3):
ALSA: compress_offload: Add 64-bit safe timestamp infrastructure
ALSA: compress_offload: Add SNDRV_COMPRESS_TSTAMP64 ioctl
ALSA: compress_offload: Add SNDRV_COMPRESS_AVAIL64 ioctl
include/sound/compress_driver.h | 2 +-
include/sound/soc-component.h | 4 +-
include/sound/soc-dai.h | 7 +-
include/uapi/sound/compress_offload.h | 35 +++++-
sound/core/compress_offload.c | 100 ++++++++++++------
sound/soc/codecs/wm_adsp.c | 4 +-
sound/soc/codecs/wm_adsp.h | 2 +-
.../intel/atom/sst-mfld-platform-compress.c | 12 ++-
sound/soc/intel/atom/sst-mfld-platform.h | 2 +-
sound/soc/intel/atom/sst/sst_drv_interface.c | 9 +-
sound/soc/intel/avs/probes.c | 2 +-
sound/soc/qcom/qdsp6/q6apm-dai.c | 26 +++--
sound/soc/qcom/qdsp6/q6asm-dai.c | 26 +++--
sound/soc/soc-component.c | 2 +-
sound/soc/soc-compress.c | 2 +-
sound/soc/soc-dai.c | 2 +-
sound/soc/sof/amd/acp-probes.c | 2 +-
sound/soc/sof/compress.c | 2 +-
sound/soc/sof/intel/hda-probes.c | 2 +-
sound/soc/sof/sof-client-probes.c | 2 +-
sound/soc/sof/sof-client-probes.h | 4 +-
sound/soc/sprd/sprd-pcm-compress.c | 6 +-
sound/soc/sprd/sprd-pcm-dma.h | 4 +-
sound/soc/uniphier/aio-compress.c | 2 +-
24 files changed, 173 insertions(+), 88 deletions(-)
--
2.50.1.565.gc32cd1483b-goog
