diff options
Diffstat (limited to 'sound/soc/dwc/designware_pcm.c')
| -rw-r--r-- | sound/soc/dwc/designware_pcm.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/sound/soc/dwc/designware_pcm.c b/sound/soc/dwc/designware_pcm.c new file mode 100644 index 0000000..4a83a22 --- /dev/null +++ b/sound/soc/dwc/designware_pcm.c @@ -0,0 +1,225 @@ +/* + * ALSA SoC Synopsys PIO PCM for I2S driver + * + * sound/soc/dwc/designware_pcm.c + * + * Copyright (C) 2016 Synopsys + * Jose Abreu <joabreu@synopsys.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/io.h> +#include <linux/rcupdate.h> +#include <sound/pcm.h> +#include <sound/pcm_params.h> +#include "local.h" + +#define BUFFER_BYTES_MAX (3 * 2 * 8 * PERIOD_BYTES_MIN) +#define PERIOD_BYTES_MIN 4096 +#define PERIODS_MIN 2 + +#define dw_pcm_tx_fn(sample_bits) \ +static unsigned int dw_pcm_tx_##sample_bits(struct dw_i2s_dev *dev, \ + struct snd_pcm_runtime *runtime, unsigned int tx_ptr, \ + bool *period_elapsed) \ +{ \ + const u##sample_bits (*p)[2] = (void *)runtime->dma_area; \ + unsigned int period_pos = tx_ptr % runtime->period_size; \ + int i; \ +\ + for (i = 0; i < dev->fifo_th; i++) { \ + iowrite32(p[tx_ptr][0], dev->i2s_base + LRBR_LTHR(0)); \ + iowrite32(p[tx_ptr][1], dev->i2s_base + RRBR_RTHR(0)); \ + period_pos++; \ + if (++tx_ptr >= runtime->buffer_size) \ + tx_ptr = 0; \ + } \ + *period_elapsed = period_pos >= runtime->period_size; \ + return tx_ptr; \ +} + +dw_pcm_tx_fn(16); +dw_pcm_tx_fn(32); + +#undef dw_pcm_tx_fn + +static const struct snd_pcm_hardware dw_pcm_hardware = { + .info = SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_MMAP_VALID | + SNDRV_PCM_INFO_BLOCK_TRANSFER, + .rates = SNDRV_PCM_RATE_32000 | + SNDRV_PCM_RATE_44100 | + SNDRV_PCM_RATE_48000, + .rate_min = 32000, + .rate_max = 48000, + .formats = SNDRV_PCM_FMTBIT_S16_LE | + SNDRV_PCM_FMTBIT_S32_LE, + .channels_min = 2, + .channels_max = 2, + .buffer_bytes_max = BUFFER_BYTES_MAX, + .period_bytes_min = PERIOD_BYTES_MIN, + .period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN, + .periods_min = PERIODS_MIN, + .periods_max = BUFFER_BYTES_MAX / PERIOD_BYTES_MIN, + .fifo_size = 16, +}; + +void dw_pcm_push_tx(struct dw_i2s_dev *dev) +{ + struct snd_pcm_substream *tx_substream; + bool tx_active, period_elapsed; + + rcu_read_lock(); + tx_substream = rcu_dereference(dev->tx_substream); + tx_active = tx_substream && snd_pcm_running(tx_substream); + if (tx_active) { + unsigned int tx_ptr = READ_ONCE(dev->tx_ptr); + unsigned int new_tx_ptr = dev->tx_fn(dev, tx_substream->runtime, + tx_ptr, &period_elapsed); + cmpxchg(&dev->tx_ptr, tx_ptr, new_tx_ptr); + + if (period_elapsed) + snd_pcm_period_elapsed(tx_substream); + } + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(dw_pcm_push_tx); + +static int dw_pcm_open(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct snd_soc_pcm_runtime *rtd = substream->private_data; + struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(rtd->cpu_dai); + + snd_soc_set_runtime_hwparams(substream, &dw_pcm_hardware); + snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS); + runtime->private_data = dev; + + return 0; +} + +static int dw_pcm_close(struct snd_pcm_substream *substream) +{ + synchronize_rcu(); + return 0; +} + +static int dw_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *hw_params) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct dw_i2s_dev *dev = runtime->private_data; + int ret; + + switch (params_channels(hw_params)) { + case 2: + break; + default: + dev_err(dev->dev, "invalid channels number\n"); + return -EINVAL; + } + + switch (params_format(hw_params)) { + case SNDRV_PCM_FORMAT_S16_LE: + dev->tx_fn = dw_pcm_tx_16; + break; + case SNDRV_PCM_FORMAT_S32_LE: + dev->tx_fn = dw_pcm_tx_32; + break; + default: + dev_err(dev->dev, "invalid format\n"); + return -EINVAL; + } + + if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK) { + dev_err(dev->dev, "only playback is available\n"); + return -EINVAL; + } + + ret = snd_pcm_lib_malloc_pages(substream, + params_buffer_bytes(hw_params)); + if (ret < 0) + return ret; + else + return 0; +} + +static int dw_pcm_hw_free(struct snd_pcm_substream *substream) +{ + return snd_pcm_lib_free_pages(substream); +} + +static int dw_pcm_trigger(struct snd_pcm_substream *substream, int cmd) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct dw_i2s_dev *dev = runtime->private_data; + int ret = 0; + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + WRITE_ONCE(dev->tx_ptr, 0); + rcu_assign_pointer(dev->tx_substream, substream); + break; + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + rcu_assign_pointer(dev->tx_substream, NULL); + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +static snd_pcm_uframes_t dw_pcm_pointer(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct dw_i2s_dev *dev = runtime->private_data; + snd_pcm_uframes_t pos = READ_ONCE(dev->tx_ptr); + + return pos < runtime->buffer_size ? pos : 0; +} + +static int dw_pcm_new(struct snd_soc_pcm_runtime *rtd) +{ + size_t size = dw_pcm_hardware.buffer_bytes_max; + + return snd_pcm_lib_preallocate_pages_for_all(rtd->pcm, + SNDRV_DMA_TYPE_CONTINUOUS, + snd_dma_continuous_data(GFP_KERNEL), size, size); +} + +static void dw_pcm_free(struct snd_pcm *pcm) +{ + snd_pcm_lib_preallocate_free_for_all(pcm); +} + +static const struct snd_pcm_ops dw_pcm_ops = { + .open = dw_pcm_open, + .close = dw_pcm_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = dw_pcm_hw_params, + .hw_free = dw_pcm_hw_free, + .trigger = dw_pcm_trigger, + .pointer = dw_pcm_pointer, +}; + +static const struct snd_soc_platform_driver dw_pcm_platform = { + .pcm_new = dw_pcm_new, + .pcm_free = dw_pcm_free, + .ops = &dw_pcm_ops, +}; + +int dw_pcm_register(struct platform_device *pdev) +{ + return devm_snd_soc_register_platform(&pdev->dev, &dw_pcm_platform); +} +EXPORT_SYMBOL_GPL(dw_pcm_register); |