[alsa-devel] [PATCH 2/3] ALSA: core: modify .ack callback to take arguments for updating appl ptr
Takashi Sakamoto
o-takashi at sakamocchi.jp
Fri May 19 05:57:05 CEST 2017
Hi,
On May 16 2017 10:01, Subhransu S. Prusty wrote:
> From: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
>
> When appl_ptr is updated let low-level driver know, e.g. to let the
> low-level driver/hardware pre-fetch data opportunistically.
>
> The existing .ack callback is extended with new attribute argument, to
> support this capability. Legacy driver subscribe to SND_PCM_ACK_LEGACY and
> doesn't process ack if it is not set. SND_PCM_ACK_APP_PTR can be used to
> process the application ptr update in the driver like in the skylake
> driver which can use this to inform position of appl pointer to host DMA
> controller. The skylake driver to process the SND_PCM_ACK_APP_PTR will be
> submitted with a separate patch set.
>
> In the ALSA core, this capability is independent from the NO_REWIND
> hardware flag. The low-level driver may however tie both options and only
> use the updated appl_ptr when rewinds are disabled due to hardware
> limitations.
>
> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
> Signed-off-by: Jaikrishna Nemallapudi <jaikrishnax.nemallapudi at intel.com>
> Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty at intel.com>
> ---
> include/sound/pcm-indirect.h | 4 ++--
> include/sound/pcm.h | 8 +++++++-
> sound/core/pcm_lib.c | 6 ++++--
> sound/core/pcm_native.c | 24 +++++++++++++++++++++++-
> sound/mips/hal2.c | 14 +++++++++++---
> sound/pci/cs46xx/cs46xx_lib.c | 18 ++++++++++++++----
> sound/pci/emu10k1/emupcm.c | 8 ++++++--
> sound/pci/rme32.c | 15 ++++++++++++---
> 8 files changed, 79 insertions(+), 18 deletions(-)
I think it better to take care of
'drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c' as well.
This is a driver for sound functionality of Raspberry PI 1/zero and some
people may still get influences from this work.
$ git grep -A20 'struct snd_pcm_ops' v4.12-rc1 | grep \\.ack
v4.12-rc1:drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c-...
...
> diff --git a/include/sound/pcm-indirect.h b/include/sound/pcm-indirect.h
> index 1df7acaaa535..2f647ff970fb 100644
> --- a/include/sound/pcm-indirect.h
> +++ b/include/sound/pcm-indirect.h
> @@ -101,7 +101,7 @@ typedef void (*snd_pcm_indirect_copy_t)(struct snd_pcm_substream *substream,
> if (rec->sw_io >= rec->sw_buffer_size)
> rec->sw_io -= rec->sw_buffer_size;
> if (substream->ops->ack)
> - substream->ops->ack(substream);
> + substream->ops->ack(substream, SND_PCM_ACK_LEGACY);
> return bytes_to_frames(substream->runtime, rec->sw_io);
> }
>
> @@ -170,7 +170,7 @@ typedef void (*snd_pcm_indirect_copy_t)(struct snd_pcm_substream *substream,
> if (rec->sw_io >= rec->sw_buffer_size)
> rec->sw_io -= rec->sw_buffer_size;
> if (substream->ops->ack)
> - substream->ops->ack(substream);
> + substream->ops->ack(substream, SND_PCM_ACK_LEGACY);
> return bytes_to_frames(substream->runtime, rec->sw_io);
> }
>
> diff --git a/include/sound/pcm.h b/include/sound/pcm.h
> index a2682c5f5b72..0151552342f9 100644
> --- a/include/sound/pcm.h
> +++ b/include/sound/pcm.h
> @@ -63,6 +63,12 @@ struct snd_pcm_hardware {
> struct snd_pcm_audio_tstamp_config; /* definitions further down */
> struct snd_pcm_audio_tstamp_report;
>
> +/*
> + * Attibute to distinguish the ack for legacy code and pointer update.
> + */
> +#define SND_PCM_ACK_LEGACY BIT(0) /* Legacy callback */
> +#define SND_PCM_ACK_APP_PTR BIT(1) /* Update pointer callback */
> +
> struct snd_pcm_ops {
> int (*open)(struct snd_pcm_substream *substream);
> int (*close)(struct snd_pcm_substream *substream);
> @@ -86,7 +92,7 @@ struct snd_pcm_ops {
> struct page *(*page)(struct snd_pcm_substream *substream,
> unsigned long offset);
> int (*mmap)(struct snd_pcm_substream *substream, struct vm_area_struct *vma);
> - int (*ack)(struct snd_pcm_substream *substream);
> + int (*ack)(struct snd_pcm_substream *substream, unsigned int ack_attr);
> };
>
> /*
> diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
> index 5088d4b8db22..b25af69a67da 100644
> --- a/sound/core/pcm_lib.c
> +++ b/sound/core/pcm_lib.c
> @@ -2089,7 +2089,8 @@ static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
> appl_ptr -= runtime->boundary;
> runtime->control->appl_ptr = appl_ptr;
> if (substream->ops->ack)
> - substream->ops->ack(substream);
> + substream->ops->ack(substream, SND_PCM_ACK_LEGACY |
> + SND_PCM_ACK_APP_PTR);
>
> offset += frames;
> size -= frames;
> @@ -2321,7 +2322,8 @@ static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
> appl_ptr -= runtime->boundary;
> runtime->control->appl_ptr = appl_ptr;
> if (substream->ops->ack)
> - substream->ops->ack(substream);
> + substream->ops->ack(substream, SND_PCM_ACK_LEGACY |
> + SND_PCM_ACK_APP_PTR);
>
> offset += frames;
> size -= frames;
> diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
> index 35dd4ca93f84..c14cdbd9ff86 100644
> --- a/sound/core/pcm_native.c
> +++ b/sound/core/pcm_native.c
> @@ -2476,6 +2476,10 @@ static snd_pcm_sframes_t snd_pcm_playback_rewind(struct snd_pcm_substream *subst
> appl_ptr += runtime->boundary;
> runtime->control->appl_ptr = appl_ptr;
> ret = frames;
> +
> + if (substream->ops->ack)
> + substream->ops->ack(substream, SND_PCM_ACK_APP_PTR);
> +
> __end:
> snd_pcm_stream_unlock_irq(substream);
> return ret;
> @@ -2527,6 +2531,10 @@ static snd_pcm_sframes_t snd_pcm_capture_rewind(struct snd_pcm_substream *substr
> appl_ptr += runtime->boundary;
> runtime->control->appl_ptr = appl_ptr;
> ret = frames;
> +
> + if (substream->ops->ack)
> + substream->ops->ack(substream, SND_PCM_ACK_APP_PTR);
> +
> __end:
> snd_pcm_stream_unlock_irq(substream);
> return ret;
> @@ -2576,6 +2584,10 @@ static snd_pcm_sframes_t snd_pcm_playback_forward(struct snd_pcm_substream *subs
> appl_ptr -= runtime->boundary;
> runtime->control->appl_ptr = appl_ptr;
> ret = frames;
> +
> + if (substream->ops->ack)
> + substream->ops->ack(substream, SND_PCM_ACK_APP_PTR);
> +
> __end:
> snd_pcm_stream_unlock_irq(substream);
> return ret;
> @@ -2625,6 +2637,10 @@ static snd_pcm_sframes_t snd_pcm_capture_forward(struct snd_pcm_substream *subst
> appl_ptr -= runtime->boundary;
> runtime->control->appl_ptr = appl_ptr;
> ret = frames;
> +
> + if (substream->ops->ack)
> + substream->ops->ack(substream, SND_PCM_ACK_APP_PTR);
> +
> __end:
> snd_pcm_stream_unlock_irq(substream);
> return ret;
> @@ -2726,8 +2742,14 @@ static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream,
> return err;
> }
> snd_pcm_stream_lock_irq(substream);
> - if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL))
> + if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL)) {
> + /* boundary wrap-around is assumed to be handled in userspace */
> control->appl_ptr = sync_ptr.c.control.appl_ptr;
> +
> + /* let low-level driver know about appl_ptr change */
> + if (substream->ops->ack)
> + substream->ops->ack(substream, SND_PCM_ACK_APP_PTR);
> + }
> else
> sync_ptr.c.control.appl_ptr = control->appl_ptr;
> if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
> diff --git a/sound/mips/hal2.c b/sound/mips/hal2.c
> index 00fc9241d266..3740381b188a 100644
> --- a/sound/mips/hal2.c
> +++ b/sound/mips/hal2.c
> @@ -577,7 +577,7 @@ static int hal2_playback_trigger(struct snd_pcm_substream *substream, int cmd)
> case SNDRV_PCM_TRIGGER_START:
> hal2->dac.pcm_indirect.hw_io = hal2->dac.buffer_dma;
> hal2->dac.pcm_indirect.hw_data = 0;
> - substream->ops->ack(substream);
> + substream->ops->ack(substream, SND_PCM_ACK_LEGACY);
> hal2_start_dac(hal2);
> break;
> case SNDRV_PCM_TRIGGER_STOP:
> @@ -610,11 +610,15 @@ static void hal2_playback_transfer(struct snd_pcm_substream *substream,
>
> }
>
> -static int hal2_playback_ack(struct snd_pcm_substream *substream)
> +static int hal2_playback_ack(struct snd_pcm_substream *substream,
> + unsigned int ack_attr)
> {
> struct snd_hal2 *hal2 = snd_pcm_substream_chip(substream);
> struct hal2_codec *dac = &hal2->dac;
>
> + if (!(ack_attr & SND_PCM_ACK_LEGACY))
> + return 0;
> +
> dac->pcm_indirect.hw_queue_size = H2_BUF_SIZE / 2;
> snd_pcm_indirect_playback_transfer(substream,
> &dac->pcm_indirect,
> @@ -702,11 +706,15 @@ static void hal2_capture_transfer(struct snd_pcm_substream *substream,
> memcpy(substream->runtime->dma_area + rec->sw_data, buf, bytes);
> }
>
> -static int hal2_capture_ack(struct snd_pcm_substream *substream)
> +static int hal2_capture_ack(struct snd_pcm_substream *substream,
> + unsigned int ack_attr)
> {
> struct snd_hal2 *hal2 = snd_pcm_substream_chip(substream);
> struct hal2_codec *adc = &hal2->adc;
>
> + if (!(ack_attr & SND_PCM_ACK_LEGACY))
> + return 0;
> +
> snd_pcm_indirect_capture_transfer(substream,
> &adc->pcm_indirect,
> hal2_capture_transfer);
> diff --git a/sound/pci/cs46xx/cs46xx_lib.c b/sound/pci/cs46xx/cs46xx_lib.c
> index e4cf3187b4dd..877edda61e45 100644
> --- a/sound/pci/cs46xx/cs46xx_lib.c
> +++ b/sound/pci/cs46xx/cs46xx_lib.c
> @@ -883,10 +883,15 @@ static void snd_cs46xx_pb_trans_copy(struct snd_pcm_substream *substream,
> memcpy(cpcm->hw_buf.area + rec->hw_data, runtime->dma_area + rec->sw_data, bytes);
> }
>
> -static int snd_cs46xx_playback_transfer(struct snd_pcm_substream *substream)
> +static int snd_cs46xx_playback_transfer(struct snd_pcm_substream *substream,
> + unsigned int ack_attr)
> {
> struct snd_pcm_runtime *runtime = substream->runtime;
> struct snd_cs46xx_pcm * cpcm = runtime->private_data;
> +
> + if (!(ack_attr & SND_PCM_ACK_LEGACY))
> + return 0;
> +
> snd_pcm_indirect_playback_transfer(substream, &cpcm->pcm_rec, snd_cs46xx_pb_trans_copy);
> return 0;
> }
> @@ -900,9 +905,14 @@ static void snd_cs46xx_cp_trans_copy(struct snd_pcm_substream *substream,
> chip->capt.hw_buf.area + rec->hw_data, bytes);
> }
>
> -static int snd_cs46xx_capture_transfer(struct snd_pcm_substream *substream)
> +static int snd_cs46xx_capture_transfer(struct snd_pcm_substream *substream,
> + unsigned int ack_attr)
> {
> struct snd_cs46xx *chip = snd_pcm_substream_chip(substream);
> +
> + if (!(ack_attr & SND_PCM_ACK_LEGACY))
> + return 0;
> +
> snd_pcm_indirect_capture_transfer(substream, &chip->capt.pcm_rec, snd_cs46xx_cp_trans_copy);
> return 0;
> }
> @@ -981,11 +991,11 @@ static int snd_cs46xx_playback_trigger(struct snd_pcm_substream *substream,
> cs46xx_dsp_pcm_link(chip,cpcm->pcm_channel);
>
> if (substream->runtime->periods != CS46XX_FRAGS)
> - snd_cs46xx_playback_transfer(substream);
> + snd_cs46xx_playback_transfer(substream, SND_PCM_ACK_LEGACY);
> #else
> spin_lock(&chip->reg_lock);
> if (substream->runtime->periods != CS46XX_FRAGS)
> - snd_cs46xx_playback_transfer(substream);
> + snd_cs46xx_playback_transfer(substream, SND_PCM_ACK_LEGACY);
> { unsigned int tmp;
> tmp = snd_cs46xx_peek(chip, BA1_PCTL);
> tmp &= 0x0000ffff;
> diff --git a/sound/pci/emu10k1/emupcm.c b/sound/pci/emu10k1/emupcm.c
> index ef1cf530c929..74c78df6e5a8 100644
> --- a/sound/pci/emu10k1/emupcm.c
> +++ b/sound/pci/emu10k1/emupcm.c
> @@ -1627,11 +1627,15 @@ static void fx8010_pb_trans_copy(struct snd_pcm_substream *substream,
> pcm->tram_shift = tram_shift;
> }
>
> -static int snd_emu10k1_fx8010_playback_transfer(struct snd_pcm_substream *substream)
> +static int snd_emu10k1_fx8010_playback_transfer(struct snd_pcm_substream *substream,
> + unsigned int ack_attr)
> {
> struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
> struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];
>
> + if (!(ack_attr & SND_PCM_ACK_LEGACY))
> + return 0;
> +
> snd_pcm_indirect_playback_transfer(substream, &pcm->pcm_rec, fx8010_pb_trans_copy);
> return 0;
> }
> @@ -1710,7 +1714,7 @@ static int snd_emu10k1_fx8010_playback_trigger(struct snd_pcm_substream *substre
> result = snd_emu10k1_fx8010_register_irq_handler(emu, snd_emu10k1_fx8010_playback_irq, pcm->gpr_running, substream, &pcm->irq);
> if (result < 0)
> goto __err;
> - snd_emu10k1_fx8010_playback_transfer(substream); /* roll the ball */
> + snd_emu10k1_fx8010_playback_transfer(substream, SND_PCM_ACK_LEGACY); /* roll the ball */
> snd_emu10k1_ptr_write(emu, emu->gpr_base + pcm->gpr_trigger, 0, 1);
> break;
> case SNDRV_PCM_TRIGGER_STOP:
> diff --git a/sound/pci/rme32.c b/sound/pci/rme32.c
> index 96d15db65dfd..3fd8de5bab26 100644
> --- a/sound/pci/rme32.c
> +++ b/sound/pci/rme32.c
> @@ -1092,7 +1092,7 @@ static int snd_rme32_capture_prepare(struct snd_pcm_substream *substream)
> if (cmd == SNDRV_PCM_TRIGGER_START && rme32->fullduplex_mode) {
> snd_pcm_group_for_each_entry(s, substream) {
> if (s == rme32->playback_substream) {
> - s->ops->ack(s);
> + s->ops->ack(s, SND_PCM_ACK_LEGACY);
> break;
> }
> }
> @@ -1145,11 +1145,15 @@ static void snd_rme32_pb_trans_copy(struct snd_pcm_substream *substream,
> substream->runtime->dma_area + rec->sw_data, bytes);
> }
>
> -static int snd_rme32_playback_fd_ack(struct snd_pcm_substream *substream)
> +static int snd_rme32_playback_fd_ack(struct snd_pcm_substream *substream,
> + unsigned int ack_attr)
> {
> struct rme32 *rme32 = snd_pcm_substream_chip(substream);
> struct snd_pcm_indirect *rec, *cprec;
>
> + if (!(ack_attr & SND_PCM_ACK_LEGACY))
> + return 0;
> +
> rec = &rme32->playback_pcm;
> cprec = &rme32->capture_pcm;
> spin_lock(&rme32->lock);
> @@ -1171,9 +1175,14 @@ static void snd_rme32_cp_trans_copy(struct snd_pcm_substream *substream,
> bytes);
> }
>
> -static int snd_rme32_capture_fd_ack(struct snd_pcm_substream *substream)
> +static int snd_rme32_capture_fd_ack(struct snd_pcm_substream *substream,
> + unsigned int ack_attr)
> {
> struct rme32 *rme32 = snd_pcm_substream_chip(substream);
> +
> + if (!(ack_attr & SND_PCM_ACK_LEGACY))
> + return 0;
> +
> snd_pcm_indirect_capture_transfer(substream, &rme32->capture_pcm,
> snd_rme32_cp_trans_copy);
> return 0;
Regards
Takashi Sakamoto
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