[alsa-devel] [PATCH v3 6/7] ASoC: tegra: config fifos on hw_param changes

[Jon Hunter]

On 04/10/2019 18:03, Ben Dooks wrote:
> On 30/09/2019 22:08, Jon Hunter wrote:
>>
>> On 30/09/2019 17:51, Ben Dooks wrote:
>>> If the hw_params uses a different bit or channel count, then we
>>> need to change both the I2S unit's CIF configuration as well as
>>> the APBIF one.
>>>
>>> To allow changing the APBIF, add a call to reconfigure the RX or
>>> TX FIFO without changing the DMA or allocation, and get the I2S
>>> driver to call it once the hw params have been calculate.
>>>
>>> Signed-off-by: Ben Dooks <ben.dooks at codethink.co.uk>
>>> ---
>>>   sound/soc/tegra/tegra30_ahub.c | 114 ++++++++++++++++++---------------
>>>   sound/soc/tegra/tegra30_ahub.h |   5 ++
>>>   sound/soc/tegra/tegra30_i2s.c  |   2 +
>>>   3 files changed, 69 insertions(+), 52 deletions(-)
>>>
>>> diff --git a/sound/soc/tegra/tegra30_ahub.c
>>> b/sound/soc/tegra/tegra30_ahub.c
>>> index 952381260dc3..58e05ceb86da 100644
>>> --- a/sound/soc/tegra/tegra30_ahub.c
>>> +++ b/sound/soc/tegra/tegra30_ahub.c
>>> @@ -84,12 +84,40 @@ static int tegra30_ahub_runtime_resume(struct
>>> device *dev)
>>>       return 0;
>>>   }
>>>   +int tegra30_ahub_setup_rx_fifo(enum tegra30_ahub_rxcif rxcif,
>>> +                   struct tegra30_ahub_cif_conf *cif_conf)
>>> +{
>>> +    int channel = rxcif - TEGRA30_AHUB_RXCIF_APBIF_RX0;
>>> +    u32 reg, val;
>>> +
>>> +    pm_runtime_get_sync(ahub->dev);
>>> +
>>> +    reg = TEGRA30_AHUB_CHANNEL_CTRL +
>>> +          (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
>>> +    val = tegra30_apbif_read(reg);
>>> +    val &= ~(TEGRA30_AHUB_CHANNEL_CTRL_RX_THRESHOLD_MASK |
>>> +         TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_MASK);
>>> +    val |= (7 << TEGRA30_AHUB_CHANNEL_CTRL_RX_THRESHOLD_SHIFT) |
>>> +           TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_EN |
>>> +           TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_16;
>>> +    tegra30_apbif_write(reg, val);
>>> +
>>> +    cif_conf->direction = TEGRA30_AUDIOCIF_DIRECTION_RX;
>>> +
>>> +    reg = TEGRA30_AHUB_CIF_RX_CTRL +
>>> +          (channel * TEGRA30_AHUB_CIF_RX_CTRL_STRIDE);
>>> +    ahub->soc_data->set_audio_cif(ahub->regmap_apbif, reg, cif_conf);
>>> +
>>> +    pm_runtime_put(ahub->dev);
>>> +    return 0;
>>> +}
>>> +EXPORT_SYMBOL_GPL(tegra30_ahub_setup_rx_fifo);
>>> +
>>>   int tegra30_ahub_allocate_rx_fifo(enum tegra30_ahub_rxcif *rxcif,
>>>                     char *dmachan, int dmachan_len,
>>>                     dma_addr_t *fiforeg)
>>>   {
>>>       int channel;
>>> -    u32 reg, val;
>>>       struct tegra30_ahub_cif_conf cif_conf;
>>>         channel = find_first_zero_bit(ahub->rx_usage,
>>> @@ -104,37 +132,14 @@ int tegra30_ahub_allocate_rx_fifo(enum
>>> tegra30_ahub_rxcif *rxcif,
>>>       *fiforeg = ahub->apbif_addr + TEGRA30_AHUB_CHANNEL_RXFIFO +
>>>              (channel * TEGRA30_AHUB_CHANNEL_RXFIFO_STRIDE);
>>>   -    pm_runtime_get_sync(ahub->dev);
>>> +    memset(&cif_conf, 0, sizeof(cif_conf));
>>>   -    reg = TEGRA30_AHUB_CHANNEL_CTRL +
>>> -          (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
>>> -    val = tegra30_apbif_read(reg);
>>> -    val &= ~(TEGRA30_AHUB_CHANNEL_CTRL_RX_THRESHOLD_MASK |
>>> -         TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_MASK);
>>> -    val |= (7 << TEGRA30_AHUB_CHANNEL_CTRL_RX_THRESHOLD_SHIFT) |
>>> -           TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_EN |
>>> -           TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_16;
>>> -    tegra30_apbif_write(reg, val);
>>> -
>>> -    cif_conf.threshold = 0;
>>>       cif_conf.audio_channels = 2;
>>>       cif_conf.client_channels = 2;
>>>       cif_conf.audio_bits = TEGRA30_AUDIOCIF_BITS_16;
>>>       cif_conf.client_bits = TEGRA30_AUDIOCIF_BITS_16;
>>> -    cif_conf.expand = 0;
>>> -    cif_conf.stereo_conv = 0;
>>> -    cif_conf.replicate = 0;
>>> -    cif_conf.direction = TEGRA30_AUDIOCIF_DIRECTION_RX;
>>> -    cif_conf.truncate = 0;
>>> -    cif_conf.mono_conv = 0;
>>> -
>>> -    reg = TEGRA30_AHUB_CIF_RX_CTRL +
>>> -          (channel * TEGRA30_AHUB_CIF_RX_CTRL_STRIDE);
>>> -    ahub->soc_data->set_audio_cif(ahub->regmap_apbif, reg, &cif_conf);
>>> -
>>> -    pm_runtime_put(ahub->dev);
>>>   -    return 0;
>>> +    return tegra30_ahub_setup_rx_fifo(*rxcif, &cif_conf);
>>
>> It seems a bit odd, that you still configure some of the cif_conf
>> members and then call tegra30_ahub_setup_rx_fifo() here. Why not just
>> allocate it and then move all the programming to
>> tegra30_ahub_setup_rx_fifo()?
> 
> I was trying to keep the behaviour the same, IIRC the original is first
> called before the format information is known.

Looks like the I2S driver is the only current user of this, so splitting
the function into two could make sense.

Cheers
Jon

-- 
nvpublic