@@ -24,6 +24,8 @@
#include <linux/firmware.h>
#include <linux/acpi.h>
+#include <sound/soc.h>
+
#include "rt5677-spi.h"
#define DRV_NAME "rt5677spi"
@@ -45,9 +47,355 @@
#define RT5677_SPI_WRITE_16 0x1
#define RT5677_SPI_READ_16 0x0
+#define RT5677_BUF_BYTES_TOTAL 0x20000
+#define RT5677_MIC_BUF_ADDR 0x60030000
+#define RT5677_MODEL_ADDR 0x5FFC9800
+#define RT5677_MIC_BUF_BYTES ((u32)(RT5677_BUF_BYTES_TOTAL - \
+ sizeof(u32)))
+#define RT5677_MIC_BUF_FIRST_READ_SIZE 0x10000
+
static struct spi_device *g_spi;
static DEFINE_MUTEX(spi_mutex);
+struct rt5677_dsp {
+ struct device *dev;
+ struct delayed_work copy_work;
+ struct mutex dma_lock;
+ struct snd_pcm_substream *substream;
+ size_t dma_offset; /* zero-based offset into runtime->dma_area */
+ size_t avail_bytes; /* number of new bytes since last period */
+ u32 mic_read_offset; /* zero-based offset into DSP's mic buffer */
+ bool new_hotword; /* a new hotword is fired */
+};
+
+static const struct snd_pcm_hardware rt5677_spi_pcm_hardware = {
+ .info = SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_INTERLEAVED,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE,
+ .period_bytes_min = PAGE_SIZE,
+ .period_bytes_max = RT5677_BUF_BYTES_TOTAL / 8,
+ .periods_min = 8,
+ .periods_max = 8,
+ .channels_min = 1,
+ .channels_max = 1,
+ .buffer_bytes_max = RT5677_BUF_BYTES_TOTAL,
+};
+
+static struct snd_soc_dai_driver rt5677_spi_dai = {
+ /* The DAI name "rt5677-dsp-cpu-dai" is not used. The actual DAI name
+ * registered with ASoC is the name of the device "spi-RT5677AA:00",
+ * because we only have one DAI. See snd_soc_register_dais().
+ */
+ .name = "rt5677-dsp-cpu-dai",
+ .id = 0,
+ .capture = {
+ .stream_name = "DSP Capture",
+ .channels_min = 1,
+ .channels_max = 1,
+ .rates = SNDRV_PCM_RATE_16000,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE,
+ },
+};
+
+/* PCM for streaming audio from the DSP buffer */
+static int rt5677_spi_pcm_open(
+ struct snd_soc_component *component,
+ struct snd_pcm_substream *substream)
+{
+ snd_soc_set_runtime_hwparams(substream, &rt5677_spi_pcm_hardware);
+ return 0;
+}
+
+static int rt5677_spi_pcm_close(
+ struct snd_soc_component *component,
+ struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct rt5677_dsp *rt5677_dsp =
+ snd_soc_component_get_drvdata(component);
+
+ cancel_delayed_work_sync(&rt5677_dsp->copy_work);
+ return 0;
+}
+
+static int rt5677_spi_hw_params(
+ struct snd_soc_component *component,
+ struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *hw_params)
+{
+ struct rt5677_dsp *rt5677_dsp =
+ snd_soc_component_get_drvdata(component);
+ int ret;
+
+ mutex_lock(&rt5677_dsp->dma_lock);
+ ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
+ params_buffer_bytes(hw_params));
+ rt5677_dsp->substream = substream;
+ mutex_unlock(&rt5677_dsp->dma_lock);
+
+ return ret;
+}
+
+static int rt5677_spi_hw_free(
+ struct snd_soc_component *component,
+ struct snd_pcm_substream *substream)
+{
+ struct rt5677_dsp *rt5677_dsp =
+ snd_soc_component_get_drvdata(component);
+
+ mutex_lock(&rt5677_dsp->dma_lock);
+ rt5677_dsp->substream = 0;
+ mutex_unlock(&rt5677_dsp->dma_lock);
+
+ return snd_pcm_lib_free_vmalloc_buffer(substream);
+}
+
+static int rt5677_spi_prepare(
+ struct snd_soc_component *component,
+ struct snd_pcm_substream *substream)
+{
+ struct rt5677_dsp *rt5677_dsp =
+ snd_soc_component_get_drvdata(component);
+
+ rt5677_dsp->dma_offset = 0;
+ rt5677_dsp->avail_bytes = 0;
+ return 0;
+}
+
+static snd_pcm_uframes_t rt5677_spi_pcm_pointer(
+ struct snd_soc_component *component,
+ struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct rt5677_dsp *rt5677_dsp =
+ snd_soc_component_get_drvdata(component);
+
+ return bytes_to_frames(runtime, rt5677_dsp->dma_offset);
+}
+
+static int rt5677_spi_mic_write_offset(u32 *mic_write_offset)
+{
+ int ret;
+ /* Grab the first 4 bytes that hold the write pointer on the
+ * dsp, and check to make sure that it points somewhere inside the
+ * buffer.
+ */
+ ret = rt5677_spi_read(RT5677_MIC_BUF_ADDR, mic_write_offset,
+ sizeof(u32));
+ if (ret)
+ return ret;
+ /* Adjust the offset so that it's zero-based */
+ *mic_write_offset = *mic_write_offset - sizeof(u32);
+ return *mic_write_offset < RT5677_MIC_BUF_BYTES ? 0 : -EFAULT;
+}
+
+/*
+ * Copy one contiguous block of audio samples from the DSP mic buffer to the
+ * dma_area of the pcm runtime. The receiving buffer may wrap around.
+ * @begin: start offset of the block to copy, in bytes.
+ * @end: offset of the first byte after the block to copy, must be greater
+ * than or equal to begin.
+ *
+ * Return: Zero if successful, or a negative error code on failure.
+ */
+static int rt5677_spi_copy_block(struct rt5677_dsp *rt5677_dsp,
+ u32 begin, u32 end)
+{
+ struct snd_pcm_runtime *runtime = rt5677_dsp->substream->runtime;
+ size_t bytes_per_frame = frames_to_bytes(runtime, 1);
+ size_t first_chunk_len, second_chunk_len;
+ int ret;
+
+ if (begin > end || runtime->dma_bytes < 2 * bytes_per_frame) {
+ dev_err(rt5677_dsp->dev,
+ "Invalid copy from (%u, %u), dma_area size %zu\n",
+ begin, end, runtime->dma_bytes);
+ return -EINVAL;
+ }
+
+ /* The block to copy is empty */
+ if (begin == end)
+ return 0;
+
+ /* If the incoming chunk is too big for the receiving buffer, only the
+ * last "receiving buffer size - one frame" bytes are copied.
+ */
+ if (end - begin > runtime->dma_bytes - bytes_per_frame)
+ begin = end - (runtime->dma_bytes - bytes_per_frame);
+
+ /* May need to split to two chunks, calculate the size of each */
+ first_chunk_len = end - begin;
+ second_chunk_len = 0;
+ if (rt5677_dsp->dma_offset + first_chunk_len > runtime->dma_bytes) {
+ /* Receiving buffer wrapped around */
+ second_chunk_len = first_chunk_len;
+ first_chunk_len = runtime->dma_bytes - rt5677_dsp->dma_offset;
+ second_chunk_len -= first_chunk_len;
+ }
+
+ /* Copy first chunk */
+ ret = rt5677_spi_read(RT5677_MIC_BUF_ADDR + sizeof(u32) + begin,
+ runtime->dma_area + rt5677_dsp->dma_offset,
+ first_chunk_len);
+ if (ret)
+ return ret;
+ rt5677_dsp->dma_offset += first_chunk_len;
+ if (rt5677_dsp->dma_offset == runtime->dma_bytes)
+ rt5677_dsp->dma_offset = 0;
+
+ /* Copy second chunk */
+ if (second_chunk_len) {
+ ret = rt5677_spi_read(RT5677_MIC_BUF_ADDR + sizeof(u32) +
+ begin + first_chunk_len, runtime->dma_area,
+ second_chunk_len);
+ if (!ret)
+ rt5677_dsp->dma_offset = second_chunk_len;
+ }
+ return ret;
+}
+
+/*
+ * Copy a given amount of audio samples from the DSP mic buffer starting at
+ * mic_read_offset, to the dma_area of the pcm runtime. The source buffer may
+ * wrap around. mic_read_offset is updated after successful copy.
+ * @amount: amount of samples to copy, in bytes.
+ *
+ * Return: Zero if successful, or a negative error code on failure.
+ */
+static int rt5677_spi_copy(struct rt5677_dsp *rt5677_dsp, u32 amount)
+{
+ int ret = 0;
+ u32 target;
+
+ if (amount == 0)
+ return ret;
+
+ target = rt5677_dsp->mic_read_offset + amount;
+ /* Copy the first chunk in DSP's mic buffer */
+ ret |= rt5677_spi_copy_block(rt5677_dsp, rt5677_dsp->mic_read_offset,
+ min(target, RT5677_MIC_BUF_BYTES));
+
+ if (target >= RT5677_MIC_BUF_BYTES) {
+ /* Wrap around, copy the second chunk */
+ target -= RT5677_MIC_BUF_BYTES;
+ ret |= rt5677_spi_copy_block(rt5677_dsp, 0, target);
+ }
+
+ if (!ret)
+ rt5677_dsp->mic_read_offset = target;
+ return ret;
+}
+
+/*
+ * A delayed work that streams audio samples from the DSP mic buffer to the
+ * dma_area of the pcm runtime via SPI.
+ */
+static void rt5677_spi_copy_work(struct work_struct *work)
+{
+ struct rt5677_dsp *rt5677_dsp =
+ container_of(work, struct rt5677_dsp, copy_work.work);
+ struct snd_pcm_runtime *runtime;
+ u32 mic_write_offset;
+ size_t new_bytes, copy_bytes, period_bytes;
+ unsigned int delay;
+ int ret = 0;
+
+ /* Ensure runtime->dma_area buffer does not go away while copying. */
+ mutex_lock(&rt5677_dsp->dma_lock);
+ if (!rt5677_dsp->substream) {
+ dev_err(rt5677_dsp->dev, "No pcm substream\n");
+ goto done;
+ }
+
+ runtime = rt5677_dsp->substream->runtime;
+
+ if (rt5677_spi_mic_write_offset(&mic_write_offset)) {
+ dev_err(rt5677_dsp->dev, "No mic_write_offset\n");
+ goto done;
+ }
+
+ /* If this is the first time that we've asked for streaming data after
+ * a hotword is fired, we should start reading from the previous 2
+ * seconds of audio from wherever the mic_write_offset is currently.
+ */
+ if (rt5677_dsp->new_hotword) {
+ rt5677_dsp->new_hotword = false;
+ /* See if buffer wraparound happens */
+ if (mic_write_offset < RT5677_MIC_BUF_FIRST_READ_SIZE)
+ rt5677_dsp->mic_read_offset = RT5677_MIC_BUF_BYTES -
+ (RT5677_MIC_BUF_FIRST_READ_SIZE -
+ mic_write_offset);
+ else
+ rt5677_dsp->mic_read_offset = mic_write_offset -
+ RT5677_MIC_BUF_FIRST_READ_SIZE;
+ }
+
+ /* Calculate the amount of new samples in bytes */
+ if (rt5677_dsp->mic_read_offset <= mic_write_offset)
+ new_bytes = mic_write_offset - rt5677_dsp->mic_read_offset;
+ else
+ new_bytes = RT5677_MIC_BUF_BYTES + mic_write_offset
+ - rt5677_dsp->mic_read_offset;
+
+ /* Copy all new samples from DSP mic buffer, one period at a time */
+ period_bytes = snd_pcm_lib_period_bytes(rt5677_dsp->substream);
+ while (new_bytes) {
+ copy_bytes = min(new_bytes, period_bytes
+ - rt5677_dsp->avail_bytes);
+ ret = rt5677_spi_copy(rt5677_dsp, copy_bytes);
+ if (ret) {
+ dev_err(rt5677_dsp->dev, "Copy failed %d\n", ret);
+ goto done;
+ }
+ rt5677_dsp->avail_bytes += copy_bytes;
+ if (rt5677_dsp->avail_bytes >= period_bytes) {
+ snd_pcm_period_elapsed(rt5677_dsp->substream);
+ rt5677_dsp->avail_bytes = 0;
+ }
+ new_bytes -= copy_bytes;
+ }
+
+ delay = bytes_to_frames(runtime, period_bytes) / (runtime->rate / 1000);
+ schedule_delayed_work(&rt5677_dsp->copy_work, msecs_to_jiffies(delay));
+done:
+ mutex_unlock(&rt5677_dsp->dma_lock);
+}
+
+struct page *rt5677_spi_pcm_page(
+ struct snd_soc_component *component,
+ struct snd_pcm_substream *substream,
+ unsigned long offset)
+{
+ return snd_pcm_lib_get_vmalloc_page(substream, offset);
+}
+
+static int rt5677_spi_pcm_probe(struct snd_soc_component *component)
+{
+ struct rt5677_dsp *rt5677_dsp;
+
+ rt5677_dsp = devm_kzalloc(component->dev, sizeof(*rt5677_dsp),
+ GFP_KERNEL);
+ rt5677_dsp->dev = &g_spi->dev;
+ mutex_init(&rt5677_dsp->dma_lock);
+ INIT_DELAYED_WORK(&rt5677_dsp->copy_work, rt5677_spi_copy_work);
+
+ snd_soc_component_set_drvdata(component, rt5677_dsp);
+ return 0;
+}
+
+static const struct snd_soc_component_driver rt5677_spi_dai_component = {
+ .name = DRV_NAME,
+ .probe = rt5677_spi_pcm_probe,
+ .open = rt5677_spi_pcm_open,
+ .close = rt5677_spi_pcm_close,
+ .hw_params = rt5677_spi_hw_params,
+ .hw_free = rt5677_spi_hw_free,
+ .prepare = rt5677_spi_prepare,
+ .pointer = rt5677_spi_pcm_pointer,
+ .page = rt5677_spi_pcm_page,
+};
+
/* Select a suitable transfer command for the next transfer to ensure
* the transfer address is always naturally aligned while minimizing
* the total number of transfers required.
@@ -218,9 +566,45 @@ int rt5677_spi_write_firmware(u32 addr, const struct firmware *fw)
}
EXPORT_SYMBOL_GPL(rt5677_spi_write_firmware);
+void rt5677_spi_hotword_detected(void)
+{
+ struct rt5677_dsp *rt5677_dsp;
+
+ if (!g_spi)
+ return;
+
+ rt5677_dsp = dev_get_drvdata(&g_spi->dev);
+ if (!rt5677_dsp) {
+ dev_err(&g_spi->dev, "Can't get rt5677_dsp\n");
+ return;
+ }
+
+ mutex_lock(&rt5677_dsp->dma_lock);
+ dev_info(rt5677_dsp->dev, "Hotword detected\n");
+ rt5677_dsp->new_hotword = true;
+ mutex_unlock(&rt5677_dsp->dma_lock);
+
+ schedule_delayed_work(&rt5677_dsp->copy_work, 0);
+}
+EXPORT_SYMBOL_GPL(rt5677_spi_hotword_detected);
+
static int rt5677_spi_probe(struct spi_device *spi)
{
+ int ret;
+
g_spi = spi;
+
+ ret = snd_soc_register_component(&spi->dev, &rt5677_spi_dai_component,
+ &rt5677_spi_dai, 1);
+ if (ret < 0)
+ dev_err(&spi->dev, "Failed to register component.\n");
+
+ return ret;
+}
+
+static int rt5677_spi_remove(struct spi_device *spi)
+{
+ snd_soc_unregister_component(&spi->dev);
return 0;
}
@@ -236,6 +620,7 @@ static struct spi_driver rt5677_spi_driver = {
.acpi_match_table = ACPI_PTR(rt5677_spi_acpi_id),
},
.probe = rt5677_spi_probe,
+ .remove = rt5677_spi_remove,
};
module_spi_driver(rt5677_spi_driver);
@@ -12,5 +12,6 @@
int rt5677_spi_read(u32 addr, void *rxbuf, size_t len);
int rt5677_spi_write(u32 addr, const void *txbuf, size_t len);
int rt5677_spi_write_firmware(u32 addr, const struct firmware *fw);
+void rt5677_spi_hotword_detected(void);
#endif /* __RT5677_SPI_H__ */