Dear Tiwai san,
First of all, thank you very much all those years you contributed on ALSA.
Couple of days ago I emailed you over updating remark fields.
The purpose of edit was providing more error and meaning to application engineers.
For example, when snd_pcm_writei returned -EIO, application engineer didn’t understand what it means because the documentation didn’t include -EIO comment.
Would you please let me know if I need to do something to apply these changes?
I’m very new to linux community, and I thought create a patch and email to relevant recipients.
However, it looks like I’m missing something here. :)
FYI, I have not changed any code.
Thank you.
Best regards,
CJ Lee
> 2020. 5. 12. 오후 6:05, changjoon.lee@xxxxxxx 작성:
>
> From: ChangJoon Lee <changjoon.lee@xxxxxxx>
>
> Signed-off-by: ChangJoon Lee <changjoon.lee@xxxxxxx>
> ---
> src/pcm/pcm.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 54 insertions(+), 3 deletions(-)
>
> diff --git a/src/pcm/pcm.c b/src/pcm/pcm.c
> index 1064044c..b53797a6 100644
> --- a/src/pcm/pcm.c
> +++ b/src/pcm/pcm.c
> @@ -820,6 +820,7 @@ int snd_pcm_nonblock(snd_pcm_t *pcm, int nonblock)
> * \param sig Signal to raise: < 0 disable, 0 default (SIGIO)
> * \param pid Process ID to signal: 0 current
> * \return 0 on success otherwise a negative error code
> + * \return -ENOSYS Async is not supported on this PCM
> *
> * A signal is raised every period.
> */
> @@ -850,6 +851,7 @@ int snd_pcm_async(snd_pcm_t *pcm, int sig, pid_t pid)
> * \param pcm PCM handle
> * \param info Information container
> * \return 0 on success otherwise a negative error code
> + * \return -ENOSYS Info is not supported on this PCM
> */
> int snd_pcm_info(snd_pcm_t *pcm, snd_pcm_info_t *info)
> {
> @@ -867,6 +869,7 @@ int snd_pcm_info(snd_pcm_t *pcm, snd_pcm_info_t *info)
> * \param pcm PCM handle
> * \param params Configuration space definition container
> * \return 0 on success otherwise a negative error code
> + * \return -EBADFD PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> */
> int snd_pcm_hw_params_current(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
> {
> @@ -933,6 +936,7 @@ int snd_pcm_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
> /** \brief Remove PCM hardware configuration and free associated resources
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \return -ENOSYS Hw_free is not supported on this PCM
> */
> int snd_pcm_hw_free(snd_pcm_t *pcm)
> {
> @@ -960,7 +964,9 @@ int snd_pcm_hw_free(snd_pcm_t *pcm)
> * \param pcm PCM handle
> * \param params Configuration container
> * \return 0 on success otherwise a negative error code
> - *
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EINVAL Incorrect parameter, avail_min cannot be 0
> + *
> * The software parameters can be changed at any time.
> * The hardware parameters cannot be changed when the stream is
> * running (active).
> @@ -1017,6 +1023,7 @@ int snd_pcm_sw_params(snd_pcm_t *pcm, snd_pcm_sw_params_t *params)
> * \param pcm PCM handle
> * \param status Status container
> * \return 0 on success otherwise a negative error code
> + * \return -ENOSYS Status is not supported on this PCM
> *
> * The function is thread-safe when built with the proper option.
> */
> @@ -1060,7 +1067,8 @@ snd_pcm_state_t snd_pcm_state(snd_pcm_t *pcm)
> * \brief (DEPRECATED) Synchronize stream position with hardware
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> - *
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + *
> * Note this function does not update the actual r/w pointer
> * for applications. The function #snd_pcm_avail_update()
> * have to be called before any mmap begin+commit operation.
> @@ -1089,6 +1097,7 @@ int snd_pcm_hwsync(snd_pcm_t *pcm)
> * \param pcm PCM handle
> * \param delayp Returned delay in frames
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> *
> * For playback the delay is defined as the time that a frame that is written
> * to the PCM stream shortly after this call will take to be actually
> @@ -1133,6 +1142,7 @@ int snd_pcm_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
> * \brief Resume from suspend, no samples are lost
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> * \retval -EAGAIN resume can't be proceed immediately (audio hardware is probably still suspended)
> * \retval -ENOSYS hardware doesn't support this feature
> *
> @@ -1166,6 +1176,8 @@ int snd_pcm_resume(snd_pcm_t *pcm)
> * \param avail Number of available frames when timestamp was grabbed
> * \param tstamp Hi-res timestamp
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -ENOSYS Hi-res timestamp is not supported on this system.
> *
> * Note this function does not update the actual r/w pointer
> * for applications.
> @@ -1194,6 +1206,9 @@ int snd_pcm_htimestamp(snd_pcm_t *pcm, snd_pcm_uframes_t *avail, snd_htimestamp_
> * \brief Prepare PCM for use
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -ENOSYS Prepare is not supported on this PCM
> + * \retval -EBADFD PCM is not in the right state (#SND_PCM_STATE_DISCONNECTED)
> *
> * The function is thread-safe when built with the proper option.
> */
> @@ -1222,6 +1237,8 @@ int snd_pcm_prepare(snd_pcm_t *pcm)
> * \brief Reset PCM position
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -ENOSYS Reset is not supported on this PCM
> *
> * Reduce PCM delay to 0.
> *
> @@ -1249,6 +1266,8 @@ int snd_pcm_reset(snd_pcm_t *pcm)
> * \brief Start a PCM
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (#SND_PCM_STATE_PREPARED)
> *
> * The function is thread-safe when built with the proper option.
> */
> @@ -1274,6 +1293,8 @@ int snd_pcm_start(snd_pcm_t *pcm)
> * \brief Stop a PCM dropping pending frames
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (Should be PREPARED,RUNNING,XRUN,PAUSED,DRAINING,SETUP or SUSPENDED)
> *
> * This function stops the PCM <i>immediately</i>.
> * The pending samples on the buffer are ignored.
> @@ -1309,7 +1330,10 @@ int snd_pcm_drop(snd_pcm_t *pcm)
> * \brief Stop a PCM preserving pending frames
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (Should be PREPARED,RUNNING,XRUN,PAUSED or DRAINING,SETUP or SUSPENDED)
> * \retval -ESTRPIPE a suspend event occurred
> + * \retval -ENOSYS Drain is not supported on this PCM
> *
> * For playback wait for all pending frames to be played and then stop
> * the PCM.
> @@ -1345,6 +1369,10 @@ int snd_pcm_drain(snd_pcm_t *pcm)
> * \param pcm PCM handle
> * \param enable 0 = resume, 1 = pause
> * \return 0 on success otherwise a negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (Should be PREPARED,RUNNING,XRUN,PAUSED or DRAINING)
> + * \retval -ESTRPIPE a suspend event occurred
> + * \retval -ENOSYS Pause is not supported on this PCM
> *
> * Note that this function works only on the hardware which supports
> * pause feature. You can check it via \link ::snd_pcm_hw_params_can_pause() \endlink
> @@ -1377,6 +1405,10 @@ int snd_pcm_pause(snd_pcm_t *pcm, int enable)
> * \brief Get safe count of frames which can be rewinded
> * \param pcm PCM handle
> * \return a positive number of frames or negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (Should be PREPARED,RUNNING,XRUN,PAUSED or DRAINING)
> + * \retval -ESTRPIPE a suspend event occurred
> + * \retval -ENOSYS Rewindable is not supported on this PCM
> *
> * Note: The snd_pcm_rewind() can accept bigger value than returned
> * by this function. But it is not guaranteed that output stream
> @@ -1412,6 +1444,9 @@ snd_pcm_sframes_t snd_pcm_rewindable(snd_pcm_t *pcm)
> * \param frames wanted displacement in frames
> * \return a positive number for actual displacement otherwise a
> * negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (Should be PREPARED,RUNNING,XRUN,PAUSED or DRAINING)
> + * \retval -ENOSYS Rewind is not supported on this PCM
> *
> * The function is thread-safe when built with the proper option.
> */
> @@ -1443,6 +1478,9 @@ snd_pcm_sframes_t snd_pcm_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
> * \brief Get safe count of frames which can be forwarded
> * \param pcm PCM handle
> * \return a positive number of frames or negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (Should be PREPARED,RUNNING,XRUN,PAUSED or DRAINING)
> + * \retval -ENOSYS Forwardable is not supported on this PCM
> *
> * Note: The snd_pcm_forward() can accept bigger value than returned
> * by this function. But it is not guaranteed that output stream
> @@ -1478,6 +1516,9 @@ snd_pcm_sframes_t snd_pcm_forwardable(snd_pcm_t *pcm)
> * \param frames wanted skip in frames
> * \return a positive number for actual skip otherwise a negative error code
> * \retval 0 means no action
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EBADFD PCM is not in the right state (Should be PREPARED,RUNNING,XRUN,PAUSED or DRAINING)
> + * \retval -ENOSYS Forward is not supported on this PCM
> *
> * The function is thread-safe when built with the proper option.
> */
> @@ -1517,6 +1558,8 @@ use_default_symbol_version(__snd_pcm_forward, snd_pcm_forward, ALSA_0.9.0rc8);
> * \param size frames to be written
> * \return a positive number of frames actually written otherwise a
> * negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EINVAL Access type is not Interleave type.
> * \retval -EBADFD PCM is not in the right state (#SND_PCM_STATE_PREPARED or #SND_PCM_STATE_RUNNING)
> * \retval -EPIPE an underrun occurred
> * \retval -ESTRPIPE a suspend event occurred (stream is suspended and waiting for an application recovery)
> @@ -1556,6 +1599,8 @@ snd_pcm_sframes_t snd_pcm_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_ufr
> * \param size frames to be written
> * \return a positive number of frames actually written otherwise a
> * negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EINVAL Access type is not Non-Interleave type.
> * \retval -EBADFD PCM is not in the right state (#SND_PCM_STATE_PREPARED or #SND_PCM_STATE_RUNNING)
> * \retval -EPIPE an underrun occurred
> * \retval -ESTRPIPE a suspend event occurred (stream is suspended and waiting for an application recovery)
> @@ -1595,6 +1640,8 @@ snd_pcm_sframes_t snd_pcm_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t
> * \param size frames to be read
> * \return a positive number of frames actually read otherwise a
> * negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EINVAL Access type is not Interleave type.
> * \retval -EBADFD PCM is not in the right state (#SND_PCM_STATE_PREPARED or #SND_PCM_STATE_RUNNING)
> * \retval -EPIPE an overrun occurred
> * \retval -ESTRPIPE a suspend event occurred (stream is suspended and waiting for an application recovery)
> @@ -1634,6 +1681,8 @@ snd_pcm_sframes_t snd_pcm_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t
> * \param size frames to be read
> * \return a positive number of frames actually read otherwise a
> * negative error code
> + * \retval -EIO PCM has not been setup (PCM isn't configured yet, or lifecycle of PCM has been ended)
> + * \retval -EINVAL Access type is not Non-Interleave type.
> * \retval -EBADFD PCM is not in the right state (#SND_PCM_STATE_PREPARED or #SND_PCM_STATE_RUNNING)
> * \retval -EPIPE an overrun occurred
> * \retval -ESTRPIPE a suspend event occurred (stream is suspended and waiting for an application recovery)
> @@ -1669,8 +1718,9 @@ snd_pcm_sframes_t snd_pcm_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t s
> /**
> * \brief Link two PCMs
> * \param pcm1 first PCM handle
> - * \param pcm2 first PCM handle
> + * \param pcm2 second PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -ENOSYS Link is not supported on pcm1
> *
> * The two PCMs will start/stop/prepare in sync.
> */
> @@ -1691,6 +1741,7 @@ int snd_pcm_link(snd_pcm_t *pcm1, snd_pcm_t *pcm2)
> * \brief Remove a PCM from a linked group
> * \param pcm PCM handle
> * \return 0 on success otherwise a negative error code
> + * \retval -ENOSYS Unlink is not supported on this PCM.
> */
> int snd_pcm_unlink(snd_pcm_t *pcm)
> {
> --
> 2.26.2
>
