Quelle  rt5514-spi.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * rt5514-spi.c  --  RT5514 SPI driver
 *
 * Copyright 2015 Realtek Semiconductor Corp.
 * Author: Oder Chiou <oder_chiou@realtek.com>
 */

#include <linux/module.h>
#include <linux/input.h>
#include <linux/spi/spi.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <linux/regulator/consumer.h>
#include <linux/pm_qos.h>
#include <linux/sysfs.h>
#include <linux/clk.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/soc-dapm.h>
#include <sound/initval.h>
#include <sound/tlv.h>

#include "rt5514-spi.h"

#define DRV_NAME "rt5514-spi"

static struct spi_device *rt5514_spi;

struct rt5514_dsp {
 struct device *dev;
 struct delayed_work copy_work;
 struct mutex dma_lock;
 struct snd_pcm_substream *substream;
 unsigned int buf_base, buf_limit, buf_rp;
 size_t buf_size, get_size, dma_offset;
};

static const struct snd_pcm_hardware rt5514_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 = 0x20000 / 8,
 .periods_min  = 8,
 .periods_max  = 8,
 .channels_min  = 1,
 .channels_max  = 1,
 .buffer_bytes_max = 0x20000,
};

static struct snd_soc_dai_driver rt5514_spi_dai = {
 .name = "rt5514-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,
 },
};

static void rt5514_spi_copy_work(struct work_struct *work)
{
 struct rt5514_dsp *rt5514_dsp =
  container_of(work, struct rt5514_dsp, copy_work.work);
 struct snd_pcm_runtime *runtime;
 size_t period_bytes, truncated_bytes = 0;
 unsigned int cur_wp, remain_data;
 u8 buf[8];

 mutex_lock(&rt5514_dsp->dma_lock);
 if (!rt5514_dsp->substream) {
  dev_err(rt5514_dsp->dev, "No pcm substream\n");
  goto done;
 }

 runtime = rt5514_dsp->substream->runtime;
 period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
 if (!period_bytes) {
  schedule_delayed_work(&rt5514_dsp->copy_work, 5);
  goto done;
 }

 if (rt5514_dsp->buf_size % period_bytes)
  rt5514_dsp->buf_size = (rt5514_dsp->buf_size / period_bytes) *
   period_bytes;

 if (rt5514_dsp->get_size >= rt5514_dsp->buf_size) {
  rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
   sizeof(buf));
  cur_wp = buf[0] | buf[1] << 8 | buf[2] << 16 |
     buf[3] << 24;

  if (cur_wp >= rt5514_dsp->buf_rp)
   remain_data = (cur_wp - rt5514_dsp->buf_rp);
  else
   remain_data =
    (rt5514_dsp->buf_limit - rt5514_dsp->buf_rp) +
    (cur_wp - rt5514_dsp->buf_base);

  if (remain_data < period_bytes) {
   schedule_delayed_work(&rt5514_dsp->copy_work, 5);
   goto done;
  }
 }

 if (rt5514_dsp->buf_rp + period_bytes <= rt5514_dsp->buf_limit) {
  rt5514_spi_burst_read(rt5514_dsp->buf_rp,
   runtime->dma_area + rt5514_dsp->dma_offset,
   period_bytes);

  if (rt5514_dsp->buf_rp + period_bytes == rt5514_dsp->buf_limit)
   rt5514_dsp->buf_rp = rt5514_dsp->buf_base;
  else
   rt5514_dsp->buf_rp += period_bytes;
 } else {
  truncated_bytes = rt5514_dsp->buf_limit - rt5514_dsp->buf_rp;
  rt5514_spi_burst_read(rt5514_dsp->buf_rp,
   runtime->dma_area + rt5514_dsp->dma_offset,
   truncated_bytes);

  rt5514_spi_burst_read(rt5514_dsp->buf_base,
   runtime->dma_area + rt5514_dsp->dma_offset +
   truncated_bytes, period_bytes - truncated_bytes);

  rt5514_dsp->buf_rp = rt5514_dsp->buf_base + period_bytes -
   truncated_bytes;
 }

 rt5514_dsp->get_size += period_bytes;
 rt5514_dsp->dma_offset += period_bytes;
 if (rt5514_dsp->dma_offset >= runtime->dma_bytes)
  rt5514_dsp->dma_offset = 0;

 snd_pcm_period_elapsed(rt5514_dsp->substream);

 schedule_delayed_work(&rt5514_dsp->copy_work, 5);

done:
 mutex_unlock(&rt5514_dsp->dma_lock);
}

static void rt5514_schedule_copy(struct rt5514_dsp *rt5514_dsp)
{
 u8 buf[8];

 if (!rt5514_dsp->substream)
  return;

 rt5514_dsp->get_size = 0;

 /**
 * The address area x1800XXXX is the register address, and it cannot
 * support spi burst read perfectly. So we use the spi burst read
 * individually to make sure the data correctly.
 */
 rt5514_spi_burst_read(RT5514_BUFFER_VOICE_BASE, (u8 *)&buf,
  sizeof(buf));
 rt5514_dsp->buf_base = buf[0] | buf[1] << 8 | buf[2] << 16 |
    buf[3] << 24;

 rt5514_spi_burst_read(RT5514_BUFFER_VOICE_LIMIT, (u8 *)&buf,
  sizeof(buf));
 rt5514_dsp->buf_limit = buf[0] | buf[1] << 8 | buf[2] << 16 |
    buf[3] << 24;

 rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
  sizeof(buf));
 rt5514_dsp->buf_rp = buf[0] | buf[1] << 8 | buf[2] << 16 |
    buf[3] << 24;

 if (rt5514_dsp->buf_rp % 8)
  rt5514_dsp->buf_rp = (rt5514_dsp->buf_rp / 8) * 8;

 rt5514_dsp->buf_size = rt5514_dsp->buf_limit - rt5514_dsp->buf_base;

 if (rt5514_dsp->buf_base && rt5514_dsp->buf_limit &&
  rt5514_dsp->buf_rp && rt5514_dsp->buf_size)
  schedule_delayed_work(&rt5514_dsp->copy_work, 0);
}

static irqreturn_t rt5514_spi_irq(int irq, void *data)
{
 struct rt5514_dsp *rt5514_dsp = data;

 rt5514_schedule_copy(rt5514_dsp);

 return IRQ_HANDLED;
}

/* PCM for streaming audio from the DSP buffer */
static int rt5514_spi_pcm_open(struct snd_soc_component *component,
          struct snd_pcm_substream *substream)
{
 snd_soc_set_runtime_hwparams(substream, &rt5514_spi_pcm_hardware);

 return 0;
}

static int rt5514_spi_hw_params(struct snd_soc_component *component,
    struct snd_pcm_substream *substream,
    struct snd_pcm_hw_params *hw_params)
{
 struct rt5514_dsp *rt5514_dsp =
  snd_soc_component_get_drvdata(component);
 u8 buf[8];

 mutex_lock(&rt5514_dsp->dma_lock);
 rt5514_dsp->substream = substream;
 rt5514_dsp->dma_offset = 0;

 /* Read IRQ status and schedule copy accordingly. */
 rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf, sizeof(buf));
 if (buf[0] & RT5514_IRQ_STATUS_BIT)
  rt5514_schedule_copy(rt5514_dsp);

 mutex_unlock(&rt5514_dsp->dma_lock);

 return 0;
}

static int rt5514_spi_hw_free(struct snd_soc_component *component,
         struct snd_pcm_substream *substream)
{
 struct rt5514_dsp *rt5514_dsp =
  snd_soc_component_get_drvdata(component);

 mutex_lock(&rt5514_dsp->dma_lock);
 rt5514_dsp->substream = NULL;
 mutex_unlock(&rt5514_dsp->dma_lock);

 cancel_delayed_work_sync(&rt5514_dsp->copy_work);

 return 0;
}

static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
  struct snd_soc_component *component,
  struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct rt5514_dsp *rt5514_dsp =
  snd_soc_component_get_drvdata(component);

 return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
}


static int rt5514_spi_pcm_probe(struct snd_soc_component *component)
{
 struct rt5514_dsp *rt5514_dsp;
 int ret;

 rt5514_dsp = devm_kzalloc(component->dev, sizeof(*rt5514_dsp),
   GFP_KERNEL);
 if (!rt5514_dsp)
  return -ENOMEM;

 rt5514_dsp->dev = &rt5514_spi->dev;
 mutex_init(&rt5514_dsp->dma_lock);
 INIT_DELAYED_WORK(&rt5514_dsp->copy_work, rt5514_spi_copy_work);
 snd_soc_component_set_drvdata(component, rt5514_dsp);

 if (rt5514_spi->irq) {
  ret = devm_request_threaded_irq(&rt5514_spi->dev,
   rt5514_spi->irq, NULL, rt5514_spi_irq,
   IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rt5514-spi",
   rt5514_dsp);
  if (ret)
   dev_err(&rt5514_spi->dev,
    "%s Failed to request IRQ: %d\n", __func__,
    ret);
  else
   device_init_wakeup(rt5514_dsp->dev, true);
 }

 return 0;
}

static int rt5514_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 const struct snd_soc_component_driver rt5514_spi_component = {
 .name   = DRV_NAME,
 .probe   = rt5514_spi_pcm_probe,
 .open   = rt5514_spi_pcm_open,
 .hw_params  = rt5514_spi_hw_params,
 .hw_free  = rt5514_spi_hw_free,
 .pointer  = rt5514_spi_pcm_pointer,
 .pcm_construct  = rt5514_spi_pcm_new,
 .legacy_dai_naming = 1,
};

/**
 * rt5514_spi_burst_read - Read data from SPI by rt5514 address.
 * @addr: Start address.
 * @rxbuf: Data Buffer for reading.
 * @len: Data length, it must be a multiple of 8.
 *
 *
 * Returns true for success.
 */
int rt5514_spi_burst_read(unsigned int addr, u8 *rxbuf, size_t len)
{
 u8 spi_cmd = RT5514_SPI_CMD_BURST_READ;
 int status;
 u8 write_buf[8];
 unsigned int i, end, offset = 0;

 struct spi_message message;
 struct spi_transfer x[3];

 while (offset < len) {
  if (offset + RT5514_SPI_BUF_LEN <= len)
   end = RT5514_SPI_BUF_LEN;
  else
   end = len % RT5514_SPI_BUF_LEN;

  write_buf[0] = spi_cmd;
  write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
  write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
  write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
  write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;

  spi_message_init(&message);
  memset(x, 0, sizeof(x));

  x[0].len = 5;
  x[0].tx_buf = write_buf;
  spi_message_add_tail(&x[0], &message);

  x[1].len = 4;
  x[1].tx_buf = write_buf;
  spi_message_add_tail(&x[1], &message);

  x[2].len = end;
  x[2].rx_buf = rxbuf + offset;
  spi_message_add_tail(&x[2], &message);

  status = spi_sync(rt5514_spi, &message);

  if (status)
   return false;

  offset += RT5514_SPI_BUF_LEN;
 }

 for (i = 0; i < len; i += 8) {
  write_buf[0] = rxbuf[i + 0];
  write_buf[1] = rxbuf[i + 1];
  write_buf[2] = rxbuf[i + 2];
  write_buf[3] = rxbuf[i + 3];
  write_buf[4] = rxbuf[i + 4];
  write_buf[5] = rxbuf[i + 5];
  write_buf[6] = rxbuf[i + 6];
  write_buf[7] = rxbuf[i + 7];

  rxbuf[i + 0] = write_buf[7];
  rxbuf[i + 1] = write_buf[6];
  rxbuf[i + 2] = write_buf[5];
  rxbuf[i + 3] = write_buf[4];
  rxbuf[i + 4] = write_buf[3];
  rxbuf[i + 5] = write_buf[2];
  rxbuf[i + 6] = write_buf[1];
  rxbuf[i + 7] = write_buf[0];
 }

 return true;
}
EXPORT_SYMBOL_GPL(rt5514_spi_burst_read);

/**
 * rt5514_spi_burst_write - Write data to SPI by rt5514 address.
 * @addr: Start address.
 * @txbuf: Data Buffer for writng.
 * @len: Data length, it must be a multiple of 8.
 *
 *
 * Returns true for success.
 */
int rt5514_spi_burst_write(u32 addr, const u8 *txbuf, size_t len)
{
 u8 spi_cmd = RT5514_SPI_CMD_BURST_WRITE;
 u8 *write_buf;
 unsigned int i, end, offset = 0;

 write_buf = kmalloc(RT5514_SPI_BUF_LEN + 6, GFP_KERNEL);

 if (write_buf == NULL)
  return -ENOMEM;

 while (offset < len) {
  if (offset + RT5514_SPI_BUF_LEN <= len)
   end = RT5514_SPI_BUF_LEN;
  else
   end = len % RT5514_SPI_BUF_LEN;

  write_buf[0] = spi_cmd;
  write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
  write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
  write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
  write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;

  for (i = 0; i < end; i += 8) {
   write_buf[i + 12] = txbuf[offset + i + 0];
   write_buf[i + 11] = txbuf[offset + i + 1];
   write_buf[i + 10] = txbuf[offset + i + 2];
   write_buf[i +  9] = txbuf[offset + i + 3];
   write_buf[i +  8] = txbuf[offset + i + 4];
   write_buf[i +  7] = txbuf[offset + i + 5];
   write_buf[i +  6] = txbuf[offset + i + 6];
   write_buf[i +  5] = txbuf[offset + i + 7];
  }

  write_buf[end + 5] = spi_cmd;

  spi_write(rt5514_spi, write_buf, end + 6);

  offset += RT5514_SPI_BUF_LEN;
 }

 kfree(write_buf);

 return 0;
}
EXPORT_SYMBOL_GPL(rt5514_spi_burst_write);

static int rt5514_spi_probe(struct spi_device *spi)
{
 int ret;

 rt5514_spi = spi;

 ret = devm_snd_soc_register_component(&spi->dev,
           &rt5514_spi_component,
           &rt5514_spi_dai, 1);
 if (ret < 0) {
  dev_err(&spi->dev, "Failed to register component.\n");
  return ret;
 }

 return 0;
}

static int rt5514_suspend(struct device *dev)
{
 int irq = to_spi_device(dev)->irq;

 if (device_may_wakeup(dev))
  enable_irq_wake(irq);

 return 0;
}

static int rt5514_resume(struct device *dev)
{
 struct rt5514_dsp *rt5514_dsp = dev_get_drvdata(dev);
 int irq = to_spi_device(dev)->irq;
 u8 buf[8];

 if (device_may_wakeup(dev))
  disable_irq_wake(irq);

 if (rt5514_dsp) {
  if (rt5514_dsp->substream) {
   rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf,
    sizeof(buf));
   if (buf[0] & RT5514_IRQ_STATUS_BIT)
    rt5514_schedule_copy(rt5514_dsp);
  }
 }

 return 0;
}

static const struct dev_pm_ops rt5514_pm_ops = {
 SYSTEM_SLEEP_PM_OPS(rt5514_suspend, rt5514_resume)
};

static const struct of_device_id rt5514_of_match[] = {
 { .compatible = "realtek,rt5514", },
 {},
};
MODULE_DEVICE_TABLE(of, rt5514_of_match);

static struct spi_driver rt5514_spi_driver = {
 .driver = {
  .name = "rt5514",
  .pm = pm_ptr(&rt5514_pm_ops),
  .of_match_table = of_match_ptr(rt5514_of_match),
 },
 .probe = rt5514_spi_probe,
};
module_spi_driver(rt5514_spi_driver);

MODULE_DESCRIPTION("RT5514 SPI driver");
MODULE_AUTHOR("Oder Chiou ");
MODULE_LICENSE("GPL v2");