// SPDX-License-Identifier: GPL-2.0-only /* * rt5677-spi.c -- RT5677 ALSA SoC audio codec driver * * Copyright 2013 Realtek Semiconductor Corp. * Author: Oder Chiou */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "rt5677.h" #include "rt5677-spi.h" #define DRV_NAME "rt5677spi" #define RT5677_SPI_BURST_LEN 240 #define RT5677_SPI_HEADER 5 #define RT5677_SPI_FREQ 6000000 /* The AddressPhase and DataPhase of SPI commands are MSB first on the wire. * DataPhase word size of 16-bit commands is 2 bytes. * DataPhase word size of 32-bit commands is 4 bytes. * DataPhase word size of burst commands is 8 bytes. * The DSP CPU is little-endian. */ #define RT5677_SPI_WRITE_BURST 0x5 #define RT5677_SPI_READ_BURST 0x4 #define RT5677_SPI_WRITE_32 0x3 #define RT5677_SPI_READ_32 0x2 #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 = snd_soc_substream_to_rtd(substream); struct snd_soc_component *codec_component = snd_soc_rtdcom_lookup(rtd, "rt5677"); struct rt5677_priv *rt5677 = snd_soc_component_get_drvdata(codec_component); struct rt5677_dsp *rt5677_dsp = snd_soc_component_get_drvdata(component); cancel_delayed_work_sync(&rt5677_dsp->copy_work); rt5677->set_dsp_vad(codec_component, false); 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); mutex_lock(&rt5677_dsp->dma_lock); rt5677_dsp->substream = substream; mutex_unlock(&rt5677_dsp->dma_lock); return 0; } 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 = NULL; mutex_unlock(&rt5677_dsp->dma_lock); return 0; } static int rt5677_spi_prepare( struct snd_soc_component *component, struct snd_pcm_substream *substream) { struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream); struct snd_soc_component *rt5677_component = snd_soc_rtdcom_lookup(rtd, "rt5677"); struct rt5677_priv *rt5677 = snd_soc_component_get_drvdata(rt5677_component); struct rt5677_dsp *rt5677_dsp = snd_soc_component_get_drvdata(component); rt5677->set_dsp_vad(rt5677_component, true); 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); } static int rt5677_spi_pcm_new(struct snd_soc_component *component, struct snd_soc_pcm_runtime *rtd) { snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0); return 0; } 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); if (!rt5677_dsp) return -ENOMEM; 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, .pcm_construct = rt5677_spi_pcm_new, .legacy_dai_naming = 1, }; /* 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. * * 3 transfer commands are available: * RT5677_SPI_READ/WRITE_16: Transfer 2 bytes * RT5677_SPI_READ/WRITE_32: Transfer 4 bytes * RT5677_SPI_READ/WRITE_BURST: Transfer any multiples of 8 bytes * * Note: * 16 Bit writes and reads are restricted to the address range * 0x18020000 ~ 0x18021000 * * For example, reading 256 bytes at 0x60030004 uses the following commands: * 0x60030004 RT5677_SPI_READ_32 4 bytes * 0x60030008 RT5677_SPI_READ_BURST 240 bytes * 0x600300F8 RT5677_SPI_READ_BURST 8 bytes * 0x60030100 RT5677_SPI_READ_32 4 bytes * * Input: * @read: true for read commands; false for write commands * @align: alignment of the next transfer address * @remain: number of bytes remaining to transfer * * Output: * @len: number of bytes to transfer with the selected command * Returns the selected command */ static u8 rt5677_spi_select_cmd(bool read, u32 align, u32 remain, u32 *len) { u8 cmd; if (align == 4 || remain <= 4) { cmd = RT5677_SPI_READ_32; *len = 4; } else { cmd = RT5677_SPI_READ_BURST; *len = (((remain - 1) >> 3) + 1) << 3; *len = min_t(u32, *len, RT5677_SPI_BURST_LEN); } return read ? cmd : cmd + 1; } /* Copy dstlen bytes from src to dst, while reversing byte order for each word. * If srclen < dstlen, zeros are padded. */ static void rt5677_spi_reverse(u8 *dst, u32 dstlen, const u8 *src, u32 srclen) { u32 w, i, si; u32 word_size = min_t(u32, dstlen, 8); for (w = 0; w < dstlen; w += word_size) { for (i = 0; i < word_size && i + w < dstlen; i++) { si = w + word_size - i - 1; dst[w + i] = si < srclen ? src[si] : 0; } } } /* Read DSP address space using SPI. addr and len have to be 4-byte aligned. */ int rt5677_spi_read(u32 addr, void *rxbuf, size_t len) { u32 offset; int status = 0; struct spi_transfer t[2]; struct spi_message m; /* +4 bytes is for the DummyPhase following the AddressPhase */ u8 header[RT5677_SPI_HEADER + 4]; u8 body[RT5677_SPI_BURST_LEN]; u8 spi_cmd; u8 *cb = rxbuf; if (!g_spi) return -ENODEV; if ((addr & 3) || (len & 3)) { dev_err(&g_spi->dev, "Bad read align 0x%x(%zu)\n", addr, len); return -EACCES; } memset(t, 0, sizeof(t)); t[0].tx_buf = header; t[0].len = sizeof(header); t[0].speed_hz = RT5677_SPI_FREQ; t[1].rx_buf = body; t[1].speed_hz = RT5677_SPI_FREQ; spi_message_init_with_transfers(&m, t, ARRAY_SIZE(t)); for (offset = 0; offset < len; offset += t[1].len) { spi_cmd = rt5677_spi_select_cmd(true, (addr + offset) & 7, len - offset, &t[1].len); /* Construct SPI message header */ header[0] = spi_cmd; header[1] = ((addr + offset) & 0xff000000) >> 24; header[2] = ((addr + offset) & 0x00ff0000) >> 16; header[3] = ((addr + offset) & 0x0000ff00) >> 8; header[4] = ((addr + offset) & 0x000000ff) >> 0; mutex_lock(&spi_mutex); status |= spi_sync(g_spi, &m); mutex_unlock(&spi_mutex); /* Copy data back to caller buffer */ rt5677_spi_reverse(cb + offset, len - offset, body, t[1].len); } return status; } EXPORT_SYMBOL_GPL(rt5677_spi_read); /* Write DSP address space using SPI. addr has to be 4-byte aligned. * If len is not 4-byte aligned, then extra zeros are written at the end * as padding. */ int rt5677_spi_write(u32 addr, const void *txbuf, size_t len) { u32 offset; int status = 0; struct spi_transfer t; struct spi_message m; /* +1 byte is for the DummyPhase following the DataPhase */ u8 buf[RT5677_SPI_HEADER + RT5677_SPI_BURST_LEN + 1]; u8 *body = buf + RT5677_SPI_HEADER; u8 spi_cmd; const u8 *cb = txbuf; if (!g_spi) return -ENODEV; if (addr & 3) { dev_err(&g_spi->dev, "Bad write align 0x%x(%zu)\n", addr, len); return -EACCES; } memset(&t, 0, sizeof(t)); t.tx_buf = buf; t.speed_hz = RT5677_SPI_FREQ; spi_message_init_with_transfers(&m, &t, 1); for (offset = 0; offset < len;) { spi_cmd = rt5677_spi_select_cmd(false, (addr + offset) & 7, len - offset, &t.len); /* Construct SPI message header */ buf[0] = spi_cmd; buf[1] = ((addr + offset) & 0xff000000) >> 24; buf[2] = ((addr + offset) & 0x00ff0000) >> 16; buf[3] = ((addr + offset) & 0x0000ff00) >> 8; buf[4] = ((addr + offset) & 0x000000ff) >> 0; /* Fetch data from caller buffer */ rt5677_spi_reverse(body, t.len, cb + offset, len - offset); offset += t.len; t.len += RT5677_SPI_HEADER + 1; mutex_lock(&spi_mutex); status |= spi_sync(g_spi, &m); mutex_unlock(&spi_mutex); } return status; } EXPORT_SYMBOL_GPL(rt5677_spi_write); int rt5677_spi_write_firmware(u32 addr, const struct firmware *fw) { return rt5677_spi_write(addr, fw->data, fw->size); } 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 = devm_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; } #ifdef CONFIG_ACPI static const struct acpi_device_id rt5677_spi_acpi_id[] = { { "RT5677AA", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, rt5677_spi_acpi_id); #endif static struct spi_driver rt5677_spi_driver = { .driver = { .name = DRV_NAME, .acpi_match_table = ACPI_PTR(rt5677_spi_acpi_id), }, .probe = rt5677_spi_probe, }; module_spi_driver(rt5677_spi_driver); MODULE_DESCRIPTION("ASoC RT5677 SPI driver"); MODULE_AUTHOR("Oder Chiou "); MODULE_LICENSE("GPL v2");