ASoC: rt5514: add rt5514 SPI driver

The device has multiple control interfaces, I2C and SPI. The I2C interface
mainly controls the register settings of codec. The SPI interface is in
order to provide the high speed transmission of data. For example, high
bandwidth memory read/write of DSP. The patch adds the rt5514 SPI driver
for loading the firmware of DSP and retrieving the voice data from DSP
after the system is waked up by specific voice.

Signed-off-by: Oder Chiou <oder_chiou@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 459 insertions, 0 deletions

diff --git a/sound/soc/codecs/rt5514-spi.c b/sound/soc/codecs/rt5514-spi.c
new file mode 100644
index 000000000000..8a9382e9787a
--- /dev/null
+++ b/sound/soc/codecs/rt5514-spi.c
@@ -0,0 +1,459 @@
+/*
+ * rt5514-spi.c  --  RT5514 SPI driver
+ *
+ * Copyright 2015 Realtek Semiconductor Corp.
+ * Author: Oder Chiou <oder_chiou@realtek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#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/gpio.h>
+#include <linux/sched.h>
+#include <linux/kthread.h>
+#include <linux/uaccess.h>
+#include <linux/miscdevice.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"
+
+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;
+	size_t dma_offset;
+	size_t dsp_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 = rt5514_dsp->substream->runtime;
+	size_t period_bytes, truncated_bytes = 0;
+
+	mutex_lock(&rt5514_dsp->dma_lock);
+	if (!rt5514_dsp->substream) {
+		dev_err(rt5514_dsp->dev, "No pcm substream\n");
+		goto done;
+	}
+
+	period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
+
+	if (rt5514_dsp->buf_size - rt5514_dsp->dsp_offset <  period_bytes)
+		period_bytes = rt5514_dsp->buf_size - rt5514_dsp->dsp_offset;
+
+	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->dma_offset += period_bytes;
+	if (rt5514_dsp->dma_offset >= runtime->dma_bytes)
+		rt5514_dsp->dma_offset = 0;
+
+	rt5514_dsp->dsp_offset += period_bytes;
+
+	snd_pcm_period_elapsed(rt5514_dsp->substream);
+
+	if (rt5514_dsp->dsp_offset < rt5514_dsp->buf_size)
+		schedule_delayed_work(&rt5514_dsp->copy_work, 5);
+done:
+	mutex_unlock(&rt5514_dsp->dma_lock);
+}
+
+/* PCM for streaming audio from the DSP buffer */
+static int rt5514_spi_pcm_open(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_pcm_substream *substream,
+			       struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct rt5514_dsp *rt5514_dsp =
+			snd_soc_platform_get_drvdata(rtd->platform);
+	int ret;
+
+	mutex_lock(&rt5514_dsp->dma_lock);
+	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
+			params_buffer_bytes(hw_params));
+	rt5514_dsp->substream = substream;
+	mutex_unlock(&rt5514_dsp->dma_lock);
+
+	return ret;
+}
+
+static int rt5514_spi_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct rt5514_dsp *rt5514_dsp =
+			snd_soc_platform_get_drvdata(rtd->platform);
+
+	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 snd_pcm_lib_free_vmalloc_buffer(substream);
+}
+
+static int rt5514_spi_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct rt5514_dsp *rt5514_dsp =
+			snd_soc_platform_get_drvdata(rtd->platform);
+	u8 buf[8];
+
+	rt5514_dsp->dma_offset = 0;
+	rt5514_dsp->dsp_offset = 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_RP, (u8 *)&buf,
+		sizeof(buf));
+	rt5514_dsp->buf_rp = buf[0] | buf[1] << 8 | buf[2] << 16 |
+				buf[3] << 24;
+
+	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_SIZE, (u8 *)&buf,
+		sizeof(buf));
+	rt5514_dsp->buf_size = buf[0] | buf[1] << 8 | buf[2] << 16 |
+				buf[3] << 24;
+
+	return 0;
+}
+
+static int rt5514_spi_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct rt5514_dsp *rt5514_dsp =
+			snd_soc_platform_get_drvdata(rtd->platform);
+
+	if (cmd == SNDRV_PCM_TRIGGER_START) {
+		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);
+	}
+
+	return 0;
+}
+
+static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
+		struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct rt5514_dsp *rt5514_dsp =
+		snd_soc_platform_get_drvdata(rtd->platform);
+
+	return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
+}
+
+static struct snd_pcm_ops rt5514_spi_pcm_ops = {
+	.open		= rt5514_spi_pcm_open,
+	.hw_params	= rt5514_spi_hw_params,
+	.hw_free	= rt5514_spi_hw_free,
+	.trigger	= rt5514_spi_trigger,
+	.prepare	= rt5514_spi_prepare,
+	.pointer	= rt5514_spi_pcm_pointer,
+	.mmap		= snd_pcm_lib_mmap_vmalloc,
+	.page		= snd_pcm_lib_get_vmalloc_page,
+};
+
+static int rt5514_spi_pcm_probe(struct snd_soc_platform *platform)
+{
+	struct rt5514_dsp *rt5514_dsp;
+
+	rt5514_dsp = devm_kzalloc(platform->dev, sizeof(*rt5514_dsp),
+			GFP_KERNEL);
+
+	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_platform_set_drvdata(platform, rt5514_dsp);
+
+	return 0;
+}
+
+static struct snd_soc_platform_driver rt5514_spi_platform = {
+	.probe = rt5514_spi_pcm_probe,
+	.ops = &rt5514_spi_pcm_ops,
+};
+
+static const struct snd_soc_component_driver rt5514_spi_dai_component = {
+	.name		= "rt5514-spi-dai",
+};
+
+/**
+ * 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;
+}
+
+/**
+ * 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 = snd_soc_register_platform(&spi->dev, &rt5514_spi_platform);
+	if (ret < 0) {
+		dev_err(&spi->dev, "Failed to register platform.\n");
+		goto err_plat;
+	}
+
+	ret = snd_soc_register_component(&spi->dev, &rt5514_spi_dai_component,
+					 &rt5514_spi_dai, 1);
+	if (ret < 0) {
+		dev_err(&spi->dev, "Failed to register component.\n");
+		goto err_comp;
+	}
+
+	return 0;
+err_comp:
+	snd_soc_unregister_platform(&spi->dev);
+err_plat:
+
+	return 0;
+}
+
+static int rt5514_spi_remove(struct spi_device *spi)
+{
+	snd_soc_unregister_component(&spi->dev);
+	snd_soc_unregister_platform(&spi->dev);
+
+	return 0;
+}
+
+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",
+		.of_match_table = of_match_ptr(rt5514_of_match),
+	},
+	.probe = rt5514_spi_probe,
+	.remove = rt5514_spi_remove,
+};
+module_spi_driver(rt5514_spi_driver);
+
+MODULE_DESCRIPTION("RT5514 SPI driver");
+MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
+MODULE_LICENSE("GPL v2");