text: // SPDX-License-Identifier: GPL-2.0
  //
  // Mediatek ALSA BT SCO CVSD/MSBC Driver
  //
  // Copyright (c) 2019 MediaTek Inc.
  // Author: KaiChieh Chuang <kaichieh.chuang@mediatek.com>
  
  #include <linux/mfd/syscon.h>
  #include <linux/module.h>
  #include <linux/of_address.h>
  #include <linux/sched/clock.h>
  
  #include <sound/soc.h>
  
  #define BTCVSD_SND_NAME "mtk-btcvsd-snd"
  
  #define BT_CVSD_TX_NREADY	BIT(21)
  #define BT_CVSD_RX_READY	BIT(22)
  #define BT_CVSD_TX_UNDERFLOW	BIT(23)
  #define BT_CVSD_RX_OVERFLOW	BIT(24)
  #define BT_CVSD_INTERRUPT	BIT(31)
  
  #define BT_CVSD_CLEAR \
  	(BT_CVSD_TX_NREADY | BT_CVSD_RX_READY | BT_CVSD_TX_UNDERFLOW |\
  	 BT_CVSD_RX_OVERFLOW | BT_CVSD_INTERRUPT)
  
  /* TX */
  #define SCO_TX_ENCODE_SIZE (60)
  /* 18 = 6 * 180 / SCO_TX_ENCODE_SIZE */
  #define SCO_TX_PACKER_BUF_NUM (18)
  
  /* RX */
  #define SCO_RX_PLC_SIZE (30)
  #define SCO_RX_PACKER_BUF_NUM (64)
  #define SCO_RX_PACKET_MASK (0x3F)
  
  #define SCO_CVSD_PACKET_VALID_SIZE 2
  
  #define SCO_PACKET_120 120
  #define SCO_PACKET_180 180
  
  #define BTCVSD_RX_PACKET_SIZE (SCO_RX_PLC_SIZE + SCO_CVSD_PACKET_VALID_SIZE)
  #define BTCVSD_TX_PACKET_SIZE (SCO_TX_ENCODE_SIZE)
  
  #define BTCVSD_RX_BUF_SIZE (BTCVSD_RX_PACKET_SIZE * SCO_RX_PACKER_BUF_NUM)
  #define BTCVSD_TX_BUF_SIZE (BTCVSD_TX_PACKET_SIZE * SCO_TX_PACKER_BUF_NUM)
  
  enum bt_sco_state {
  	BT_SCO_STATE_IDLE,
  	BT_SCO_STATE_RUNNING,
  	BT_SCO_STATE_ENDING,
  	BT_SCO_STATE_LOOPBACK,
  };
  
  enum bt_sco_direct {
  	BT_SCO_DIRECT_BT2ARM,
  	BT_SCO_DIRECT_ARM2BT,
  };
  
  enum bt_sco_packet_len {
  	BT_SCO_CVSD_30 = 0,
  	BT_SCO_CVSD_60,
  	BT_SCO_CVSD_90,
  	BT_SCO_CVSD_120,
  	BT_SCO_CVSD_10,
  	BT_SCO_CVSD_20,
  	BT_SCO_CVSD_MAX,
  };
  
  enum BT_SCO_BAND {
  	BT_SCO_NB,
  	BT_SCO_WB,
  };
  
  struct mtk_btcvsd_snd_hw_info {
  	unsigned int num_valid_addr;
  	unsigned long bt_sram_addr[20];
  	unsigned int packet_length;
  	unsigned int packet_num;
  };
  
  struct mtk_btcvsd_snd_stream {
  	struct snd_pcm_substream *substream;
  	int stream;
  
  	enum bt_sco_state state;
  
  	unsigned int packet_size;
  	unsigned int buf_size;
  	u8 temp_packet_buf[SCO_PACKET_180];
  
  	int packet_w;
  	int packet_r;
  	snd_pcm_uframes_t prev_frame;
  	int prev_packet_idx;
  
  	unsigned int xrun:1;
  	unsigned int timeout:1;
  	unsigned int mute:1;
  	unsigned int trigger_start:1;
  	unsigned int wait_flag:1;
  	unsigned int rw_cnt;
  
  	unsigned long long time_stamp;
  	unsigned long long buf_data_equivalent_time;
  
  	struct mtk_btcvsd_snd_hw_info buffer_info;
  };
  
  struct mtk_btcvsd_snd {
  	struct device *dev;
  	int irq_id;
  
  	struct regmap *infra;
  	void __iomem *bt_pkv_base;
  	void __iomem *bt_sram_bank2_base;
  
  	unsigned int infra_misc_offset;
  	unsigned int conn_bt_cvsd_mask;
  	unsigned int cvsd_mcu_read_offset;
  	unsigned int cvsd_mcu_write_offset;
  	unsigned int cvsd_packet_indicator;
  
  	u32 *bt_reg_pkt_r;
  	u32 *bt_reg_pkt_w;
  	u32 *bt_reg_ctl;
  
  	unsigned int irq_disabled:1;
  
  	spinlock_t tx_lock;	/* spinlock for bt tx stream control */
  	spinlock_t rx_lock;	/* spinlock for bt rx stream control */
  	wait_queue_head_t tx_wait;
  	wait_queue_head_t rx_wait;
  
  	struct mtk_btcvsd_snd_stream *tx;
  	struct mtk_btcvsd_snd_stream *rx;
  	u8 tx_packet_buf[BTCVSD_TX_BUF_SIZE];
  	u8 rx_packet_buf[BTCVSD_RX_BUF_SIZE];
  
  	enum BT_SCO_BAND band;
  };
  
  struct mtk_btcvsd_snd_time_buffer_info {
  	unsigned long long data_count_equi_time;
  	unsigned long long time_stamp_us;
  };
  
  static const unsigned int btsco_packet_valid_mask[BT_SCO_CVSD_MAX][6] = {
  	{0x1, 0x1 << 1, 0x1 << 2, 0x1 << 3, 0x1 << 4, 0x1 << 5},
  	{0x1, 0x1, 0x2, 0x2, 0x4, 0x4},
  	{0x1, 0x1, 0x1, 0x2, 0x2, 0x2},
  	{0x1, 0x1, 0x1, 0x1, 0x0, 0x0},
  	{0x7, 0x7 << 3, 0x7 << 6, 0x7 << 9, 0x7 << 12, 0x7 << 15},
  	{0x3, 0x3 << 1, 0x3 << 3, 0x3 << 4, 0x3 << 6, 0x3 << 7},
  };
  
  static const unsigned int btsco_packet_info[BT_SCO_CVSD_MAX][4] = {
  	{30, 6, SCO_PACKET_180 / SCO_TX_ENCODE_SIZE,
  	 SCO_PACKET_180 / SCO_RX_PLC_SIZE},
  	{60, 3, SCO_PACKET_180 / SCO_TX_ENCODE_SIZE,
  	 SCO_PACKET_180 / SCO_RX_PLC_SIZE},
  	{90, 2, SCO_PACKET_180 / SCO_TX_ENCODE_SIZE,
  	 SCO_PACKET_180 / SCO_RX_PLC_SIZE},
  	{120, 1, SCO_PACKET_120 / SCO_TX_ENCODE_SIZE,
  	 SCO_PACKET_120 / SCO_RX_PLC_SIZE},
  	{10, 18, SCO_PACKET_180 / SCO_TX_ENCODE_SIZE,
  	 SCO_PACKET_180 / SCO_RX_PLC_SIZE},
  	{20, 9, SCO_PACKET_180 / SCO_TX_ENCODE_SIZE,
  	 SCO_PACKET_180 / SCO_RX_PLC_SIZE},
  };
  
  static const u8 table_msbc_silence[SCO_PACKET_180] = {
  	0x01, 0x38, 0xad, 0x00, 0x00, 0xc5, 0x00, 0x00, 0x00, 0x00,
  	0x77, 0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6d,
  	0xdd, 0xb6, 0xdb, 0x77, 0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7,
  	0x76, 0xdb, 0x6d, 0xdd, 0xb6, 0xdb, 0x77, 0x6d, 0xb6, 0xdd,
  	0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6d, 0xdd, 0xb6, 0xdb, 0x77,
  	0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6c, 0x00,
  	0x01, 0xc8, 0xad, 0x00, 0x00, 0xc5, 0x00, 0x00, 0x00, 0x00,
  	0x77, 0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6d,
  	0xdd, 0xb6, 0xdb, 0x77, 0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7,
  	0x76, 0xdb, 0x6d, 0xdd, 0xb6, 0xdb, 0x77, 0x6d, 0xb6, 0xdd,
  	0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6d, 0xdd, 0xb6, 0xdb, 0x77,
  	0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6c, 0x00,
  	0x01, 0xf8, 0xad, 0x00, 0x00, 0xc5, 0x00, 0x00, 0x00, 0x00,
  	0x77, 0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6d,
  	0xdd, 0xb6, 0xdb, 0x77, 0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7,
  	0x76, 0xdb, 0x6d, 0xdd, 0xb6, 0xdb, 0x77, 0x6d, 0xb6, 0xdd,
  	0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6d, 0xdd, 0xb6, 0xdb, 0x77,
  	0x6d, 0xb6, 0xdd, 0xdb, 0x6d, 0xb7, 0x76, 0xdb, 0x6c, 0x00
  };
  
  static void mtk_btcvsd_snd_irq_enable(struct mtk_btcvsd_snd *bt)
  {
  	regmap_update_bits(bt->infra, bt->infra_misc_offset,
  			   bt->conn_bt_cvsd_mask, 0);
  }
  
  static void mtk_btcvsd_snd_irq_disable(struct mtk_btcvsd_snd *bt)
  {
  	regmap_update_bits(bt->infra, bt->infra_misc_offset,
  			   bt->conn_bt_cvsd_mask, bt->conn_bt_cvsd_mask);
  }
  
  static void mtk_btcvsd_snd_set_state(struct mtk_btcvsd_snd *bt,
  				     struct mtk_btcvsd_snd_stream *bt_stream,
  				     int state)
  {
  	dev_dbg(bt->dev, "%s(), stream %d, state %d, tx->state %d, rx->state %d, irq_disabled %d\n",
  		__func__,
  		bt_stream->stream, state,
  		bt->tx->state, bt->rx->state, bt->irq_disabled);
  
  	bt_stream->state = state;
  
  	if (bt->tx->state == BT_SCO_STATE_IDLE &&
  	    bt->rx->state == BT_SCO_STATE_IDLE) {
  		if (!bt->irq_disabled) {
  			disable_irq(bt->irq_id);
  			mtk_btcvsd_snd_irq_disable(bt);
  			bt->irq_disabled = 1;
  		}
  	} else {
  		if (bt->irq_disabled) {
  			enable_irq(bt->irq_id);
  			mtk_btcvsd_snd_irq_enable(bt);
  			bt->irq_disabled = 0;
  		}
  	}
  }
  
  static int mtk_btcvsd_snd_tx_init(struct mtk_btcvsd_snd *bt)
  {
  	memset(bt->tx, 0, sizeof(*bt->tx));
  	memset(bt->tx_packet_buf, 0, sizeof(bt->tx_packet_buf));
  
  	bt->tx->packet_size = BTCVSD_TX_PACKET_SIZE;
  	bt->tx->buf_size = BTCVSD_TX_BUF_SIZE;
  	bt->tx->timeout = 0;
  	bt->tx->rw_cnt = 0;
  	bt->tx->stream = SNDRV_PCM_STREAM_PLAYBACK;
  	return 0;
  }
  
  static int mtk_btcvsd_snd_rx_init(struct mtk_btcvsd_snd *bt)
  {
  	memset(bt->rx, 0, sizeof(*bt->rx));
  	memset(bt->rx_packet_buf, 0, sizeof(bt->rx_packet_buf));
  
  	bt->rx->packet_size = BTCVSD_RX_PACKET_SIZE;
  	bt->rx->buf_size = BTCVSD_RX_BUF_SIZE;
  	bt->rx->timeout = 0;
  	bt->rx->rw_cnt = 0;
  	bt->rx->stream = SNDRV_PCM_STREAM_CAPTURE;
  	return 0;
  }
  
  static void get_tx_time_stamp(struct mtk_btcvsd_snd *bt,
  			      struct mtk_btcvsd_snd_time_buffer_info *ts)
  {
  	ts->time_stamp_us = bt->tx->time_stamp;
  	ts->data_count_equi_time = bt->tx->buf_data_equivalent_time;
  }
  
  static void get_rx_time_stamp(struct mtk_btcvsd_snd *bt,
  			      struct mtk_btcvsd_snd_time_buffer_info *ts)
  {
  	ts->time_stamp_us = bt->rx->time_stamp;
  	ts->data_count_equi_time = bt->rx->buf_data_equivalent_time;
  }
  
  static int btcvsd_bytes_to_frame(struct snd_pcm_substream *substream,
  				 int bytes)
  {
  	int count = bytes;
  	struct snd_pcm_runtime *runtime = substream->runtime;
  
  	if (runtime->format == SNDRV_PCM_FORMAT_S32_LE ||
  	    runtime->format == SNDRV_PCM_FORMAT_U32_LE)
  		count = count >> 2;
  	else
  		count = count >> 1;
  
  	count = count / runtime->channels;
  	return count;
  }
  
  static void mtk_btcvsd_snd_data_transfer(enum bt_sco_direct dir,
  					 u8 *src, u8 *dst,
  					 unsigned int blk_size,
  					 unsigned int blk_num)
  {
  	unsigned int i, j;
  
  	if (blk_size == 60 || blk_size == 120 || blk_size == 20) {
  		u32 *src_32 = (u32 *)src;
  		u32 *dst_32 = (u32 *)dst;
  
  		for (i = 0; i < (blk_size * blk_num / 4); i++)
  			*dst_32++ = *src_32++;
  	} else {
  		u16 *src_16 = (u16 *)src;
  		u16 *dst_16 = (u16 *)dst;
  
  		for (j = 0; j < blk_num; j++) {
  			for (i = 0; i < (blk_size / 2); i++)
  				*dst_16++ = *src_16++;
  
  			if (dir == BT_SCO_DIRECT_BT2ARM)
  				src_16++;
  			else
  				dst_16++;
  		}
  	}
  }
  
  /* write encoded mute data to bt sram */
  static int btcvsd_tx_clean_buffer(struct mtk_btcvsd_snd *bt)
  {
  	unsigned int i;
  	unsigned int num_valid_addr;
  	unsigned long flags;
  	enum BT_SCO_BAND band = bt->band;
  
  	/* prepare encoded mute data */
  	if (band == BT_SCO_NB)
  		memset(bt->tx->temp_packet_buf, 170, SCO_PACKET_180);
  	else
  		memcpy(bt->tx->temp_packet_buf,
  		       table_msbc_silence, SCO_PACKET_180);
  
  	/* write mute data to bt tx sram buffer */
  	spin_lock_irqsave(&bt->tx_lock, flags);
  	num_valid_addr = bt->tx->buffer_info.num_valid_addr;
  
  	dev_info(bt->dev, "%s(), band %d, num_valid_addr %u\n",
  		 __func__, band, num_valid_addr);
  
  	for (i = 0; i < num_valid_addr; i++) {
  		void *dst;
  
  		dev_info(bt->dev, "%s(), clean addr 0x%lx\n", __func__,
  			 bt->tx->buffer_info.bt_sram_addr[i]);
  
  		dst = (void *)bt->tx->buffer_info.bt_sram_addr[i];
  
  		mtk_btcvsd_snd_data_transfer(BT_SCO_DIRECT_ARM2BT,
  					     bt->tx->temp_packet_buf, dst,
  					     bt->tx->buffer_info.packet_length,
  					     bt->tx->buffer_info.packet_num);
  	}
  	spin_unlock_irqrestore(&bt->tx_lock, flags);
  
  	return 0;
  }
  
  static int mtk_btcvsd_read_from_bt(struct mtk_btcvsd_snd *bt,
  				   enum bt_sco_packet_len packet_type,
  				   unsigned int packet_length,
  				   unsigned int packet_num,
  				   unsigned int blk_size,
  				   unsigned int control)
  {
  	unsigned int i;
  	int pv;
  	u8 *src;
  	unsigned int packet_buf_ofs;
  	unsigned long flags;
  	unsigned long connsys_addr_rx, ap_addr_rx;
  
  	connsys_addr_rx = *bt->bt_reg_pkt_r;
  	ap_addr_rx = (unsigned long)bt->bt_sram_bank2_base +
  		     (connsys_addr_rx & 0xFFFF);
  
  	if (connsys_addr_rx == 0xdeadfeed) {
  		/* bt return 0xdeadfeed if read register during bt sleep */
  		dev_warn(bt->dev, "%s(), connsys_addr_rx == 0xdeadfeed",
  			 __func__);
  		return -EIO;
  	}
  
  	src = (u8 *)ap_addr_rx;
  
  	mtk_btcvsd_snd_data_transfer(BT_SCO_DIRECT_BT2ARM, src,
  				     bt->rx->temp_packet_buf, packet_length,
  				     packet_num);
  
  	spin_lock_irqsave(&bt->rx_lock, flags);
  	for (i = 0; i < blk_size; i++) {
  		packet_buf_ofs = (bt->rx->packet_w & SCO_RX_PACKET_MASK) *
  				 bt->rx->packet_size;
  		memcpy(bt->rx_packet_buf + packet_buf_ofs,
  		       bt->rx->temp_packet_buf + (SCO_RX_PLC_SIZE * i),
  		       SCO_RX_PLC_SIZE);
  		if ((control & btsco_packet_valid_mask[packet_type][i]) ==
  		    btsco_packet_valid_mask[packet_type][i])
  			pv = 1;
  		else
  			pv = 0;
  
  		packet_buf_ofs += SCO_RX_PLC_SIZE;
  		memcpy(bt->rx_packet_buf + packet_buf_ofs, (void *)&pv,
  		       SCO_CVSD_PACKET_VALID_SIZE);
  		bt->rx->packet_w++;
  	}
  	spin_unlock_irqrestore(&bt->rx_lock, flags);
  	return 0;
  }
  
  static int mtk_btcvsd_write_to_bt(struct mtk_btcvsd_snd *bt,
  				  enum bt_sco_packet_len packet_type,
  				  unsigned int packet_length,
  				  unsigned int packet_num,
  				  unsigned int blk_size)
  {
  	unsigned int i;
  	unsigned long flags;
  	u8 *dst;
  	unsigned long connsys_addr_tx, ap_addr_tx;
  	bool new_ap_addr_tx = true;
  
  	connsys_addr_tx = *bt->bt_reg_pkt_w;
  	ap_addr_tx = (unsigned long)bt->bt_sram_bank2_base +
  		     (connsys_addr_tx & 0xFFFF);
  
  	if (connsys_addr_tx == 0xdeadfeed) {
  		/* bt return 0xdeadfeed if read register during bt sleep */
  		dev_warn(bt->dev, "%s(), connsys_addr_tx == 0xdeadfeed\n",
  			 __func__);
  		return -EIO;
  	}
  
  	spin_lock_irqsave(&bt->tx_lock, flags);
  	for (i = 0; i < blk_size; i++) {
  		memcpy(bt->tx->temp_packet_buf + (bt->tx->packet_size * i),
  		       (bt->tx_packet_buf +
  			(bt->tx->packet_r % SCO_TX_PACKER_BUF_NUM) *
  			bt->tx->packet_size),
  		       bt->tx->packet_size);
  
  		bt->tx->packet_r++;
  	}
  	spin_unlock_irqrestore(&bt->tx_lock, flags);
  
  	dst = (u8 *)ap_addr_tx;
  
  	if (!bt->tx->mute) {
  		mtk_btcvsd_snd_data_transfer(BT_SCO_DIRECT_ARM2BT,
  					     bt->tx->temp_packet_buf, dst,
  					     packet_length, packet_num);
  	}
  
  	/* store bt tx buffer sram info */
  	bt->tx->buffer_info.packet_length = packet_length;
  	bt->tx->buffer_info.packet_num = packet_num;
  	for (i = 0; i < bt->tx->buffer_info.num_valid_addr; i++) {
  		if (bt->tx->buffer_info.bt_sram_addr[i] == ap_addr_tx) {
  			new_ap_addr_tx = false;
  			break;
  		}
  	}
  	if (new_ap_addr_tx) {
  		unsigned int next_idx;
  
  		spin_lock_irqsave(&bt->tx_lock, flags);
  		bt->tx->buffer_info.num_valid_addr++;
  		next_idx = bt->tx->buffer_info.num_valid_addr - 1;
  		bt->tx->buffer_info.bt_sram_addr[next_idx] = ap_addr_tx;
  		spin_unlock_irqrestore(&bt->tx_lock, flags);
  		dev_info(bt->dev, "%s(), new ap_addr_tx = 0x%lx, num_valid_addr %d\n",
  			 __func__, ap_addr_tx,
  			 bt->tx->buffer_info.num_valid_addr);
  	}
  
  	if (bt->tx->mute)
  		btcvsd_tx_clean_buffer(bt);
  
  	return 0;
  }
  
  static irqreturn_t mtk_btcvsd_snd_irq_handler(int irq_id, void *dev)
  {
  	struct mtk_btcvsd_snd *bt = dev;
  	unsigned int packet_type, packet_num, packet_length;
  	unsigned int buf_cnt_tx, buf_cnt_rx, control;
  
  	if (bt->rx->state != BT_SCO_STATE_RUNNING &&
  	    bt->rx->state != BT_SCO_STATE_ENDING &&
  	    bt->tx->state != BT_SCO_STATE_RUNNING &&
  	    bt->tx->state != BT_SCO_STATE_ENDING &&
  	    bt->tx->state != BT_SCO_STATE_LOOPBACK) {
  		dev_warn(bt->dev, "%s(), in idle state: rx->state: %d, tx->state: %d\n",
  			 __func__, bt->rx->state, bt->tx->state);
  		goto irq_handler_exit;
  	}
  
  	control = *bt->bt_reg_ctl;
  	packet_type = (control >> 18) & 0x7;
  
  	if (((control >> 31) & 1) == 0) {
  		dev_warn(bt->dev, "%s(), ((control >> 31) & 1) == 0, control 0x%x\n",
  			 __func__, control);
  		goto irq_handler_exit;
  	}
  
  	if (packet_type >= BT_SCO_CVSD_MAX) {
  		dev_warn(bt->dev, "%s(), invalid packet_type %u, exit\n",
  			 __func__, packet_type);
  		goto irq_handler_exit;
  	}
  
  	packet_length = btsco_packet_info[packet_type][0];
  	packet_num = btsco_packet_info[packet_type][1];
  	buf_cnt_tx = btsco_packet_info[packet_type][2];
  	buf_cnt_rx = btsco_packet_info[packet_type][3];
  
  	if (bt->tx->state == BT_SCO_STATE_LOOPBACK) {
  		u8 *src, *dst;
  		unsigned long connsys_addr_rx, ap_addr_rx;
  		unsigned long connsys_addr_tx, ap_addr_tx;
  
  		connsys_addr_rx = *bt->bt_reg_pkt_r;
  		ap_addr_rx = (unsigned long)bt->bt_sram_bank2_base +
  			     (connsys_addr_rx & 0xFFFF);
  
  		connsys_addr_tx = *bt->bt_reg_pkt_w;
  		ap_addr_tx = (unsigned long)bt->bt_sram_bank2_base +
  			     (connsys_addr_tx & 0xFFFF);
  
  		if (connsys_addr_tx == 0xdeadfeed ||
  		    connsys_addr_rx == 0xdeadfeed) {
  			/* bt return 0xdeadfeed if read reg during bt sleep */
  			dev_warn(bt->dev, "%s(), connsys_addr_tx == 0xdeadfeed\n",
  				 __func__);
  			goto irq_handler_exit;
  		}
  
  		src = (u8 *)ap_addr_rx;
  		dst = (u8 *)ap_addr_tx;
  
  		mtk_btcvsd_snd_data_transfer(BT_SCO_DIRECT_BT2ARM, src,
  					     bt->tx->temp_packet_buf,
  					     packet_length,
  					     packet_num);
  		mtk_btcvsd_snd_data_transfer(BT_SCO_DIRECT_ARM2BT,
  					     bt->tx->temp_packet_buf, dst,
  					     packet_length,
  					     packet_num);
  		bt->rx->rw_cnt++;
  		bt->tx->rw_cnt++;
  	}
  
  	if (bt->rx->state == BT_SCO_STATE_RUNNING ||
  	    bt->rx->state == BT_SCO_STATE_ENDING) {
  		if (bt->rx->xrun) {
  			if (bt->rx->packet_w - bt->rx->packet_r <=
  			    SCO_RX_PACKER_BUF_NUM - 2 * buf_cnt_rx) {
  				/*
  				 * free space is larger then
  				 * twice interrupt rx data size
  				 */
  				bt->rx->xrun = 0;
  				dev_warn(bt->dev, "%s(), rx->xrun 0!\n",
  					 __func__);
  			}
  		}
  
  		if (!bt->rx->xrun &&
  		    (bt->rx->packet_w - bt->rx->packet_r <=
  		     SCO_RX_PACKER_BUF_NUM - buf_cnt_rx)) {
  			mtk_btcvsd_read_from_bt(bt,
  						packet_type,
  						packet_length,
  						packet_num,
  						buf_cnt_rx,
  						control);
  			bt->rx->rw_cnt++;
  		} else {
  			bt->rx->xrun = 1;
  			dev_warn(bt->dev, "%s(), rx->xrun 1\n", __func__);
  		}
  	}
  
  	/* tx */
  	bt->tx->timeout = 0;
  	if ((bt->tx->state == BT_SCO_STATE_RUNNING ||
  	     bt->tx->state == BT_SCO_STATE_ENDING) &&
  	    bt->tx->trigger_start) {
  		if (bt->tx->xrun) {
  			/* prepared data is larger then twice
  			 * interrupt tx data size
  			 */
  			if (bt->tx->packet_w - bt->tx->packet_r >=
  			    2 * buf_cnt_tx) {
  				bt->tx->xrun = 0;
  				dev_warn(bt->dev, "%s(), tx->xrun 0\n",
  					 __func__);
  			}
  		}
  
  		if ((!bt->tx->xrun &&
  		     (bt->tx->packet_w - bt->tx->packet_r >= buf_cnt_tx)) ||
  		    bt->tx->state == BT_SCO_STATE_ENDING) {
  			mtk_btcvsd_write_to_bt(bt,
  					       packet_type,
  					       packet_length,
  					       packet_num,
  					       buf_cnt_tx);
  			bt->tx->rw_cnt++;
  		} else {
  			bt->tx->xrun = 1;
  			dev_warn(bt->dev, "%s(), tx->xrun 1\n", __func__);
  		}
  	}
  
  	*bt->bt_reg_ctl &= ~BT_CVSD_CLEAR;
  
  	if (bt->rx->state == BT_SCO_STATE_RUNNING ||
  	    bt->rx->state == BT_SCO_STATE_ENDING) {
  		bt->rx->wait_flag = 1;
  		wake_up_interruptible(&bt->rx_wait);
  		snd_pcm_period_elapsed(bt->rx->substream);
  	}
  	if (bt->tx->state == BT_SCO_STATE_RUNNING ||
  	    bt->tx->state == BT_SCO_STATE_ENDING) {
  		bt->tx->wait_flag = 1;
  		wake_up_interruptible(&bt->tx_wait);
  		snd_pcm_period_elapsed(bt->tx->substream);
  	}
  
  	return IRQ_HANDLED;
  irq_handler_exit:
  	*bt->bt_reg_ctl &= ~BT_CVSD_CLEAR;
  	return IRQ_HANDLED;
  }
  
  static int wait_for_bt_irq(struct mtk_btcvsd_snd *bt,
  			   struct mtk_btcvsd_snd_stream *bt_stream)
  {
  	unsigned long long t1, t2;
  	/* one interrupt period = 22.5ms */
  	unsigned long long timeout_limit = 22500000;
  	int max_timeout_trial = 2;
  	int ret;
  
  	bt_stream->wait_flag = 0;
  
  	while (max_timeout_trial && !bt_stream->wait_flag) {
  		t1 = sched_clock();
  		if (bt_stream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  			ret = wait_event_interruptible_timeout(bt->tx_wait,
  				bt_stream->wait_flag,
  				nsecs_to_jiffies(timeout_limit));
  		} else {
  			ret = wait_event_interruptible_timeout(bt->rx_wait,
  				bt_stream->wait_flag,
  				nsecs_to_jiffies(timeout_limit));
  		}
  
  		t2 = sched_clock();
  		t2 = t2 - t1; /* in ns (10^9) */
  
  		if (t2 > timeout_limit) {
  			dev_warn(bt->dev, "%s(), stream %d, timeout %llu, limit %llu, ret %d, flag %d\n",
  				 __func__, bt_stream->stream,
  				 t2, timeout_limit, ret,
  				 bt_stream->wait_flag);
  		}
  
  		if (ret < 0) {
  			/*
  			 * error, -ERESTARTSYS if it was interrupted by
  			 * a signal
  			 */
  			dev_warn(bt->dev, "%s(), stream %d, error, trial left %d\n",
  				 __func__,
  				 bt_stream->stream, max_timeout_trial);
  
  			bt_stream->timeout = 1;
  			return ret;
  		} else if (ret == 0) {
  			/* conidtion is false after timeout */
  			max_timeout_trial--;
  			dev_warn(bt->dev, "%s(), stream %d, error, timeout, condition is false, trial left %d\n",
  				 __func__,
  				 bt_stream->stream, max_timeout_trial);
  
  			if (max_timeout_trial <= 0) {
  				bt_stream->timeout = 1;
  				return -ETIME;
  			}
  		}
  	}
  
  	return 0;
  }
  
  static ssize_t mtk_btcvsd_snd_read(struct mtk_btcvsd_snd *bt,
  				   char __user *buf,
  				   size_t count)
  {
  	ssize_t read_size = 0, read_count = 0, cur_read_idx, cont;
  	unsigned int cur_buf_ofs = 0;
  	unsigned long avail;
  	unsigned long flags;
  	unsigned int packet_size = bt->rx->packet_size;
  
  	while (count) {
  		spin_lock_irqsave(&bt->rx_lock, flags);
  		/* available data in RX packet buffer */
  		avail = (bt->rx->packet_w - bt->rx->packet_r) * packet_size;
  
  		cur_read_idx = (bt->rx->packet_r & SCO_RX_PACKET_MASK) *
  			       packet_size;
  		spin_unlock_irqrestore(&bt->rx_lock, flags);
  
  		if (!avail) {
  			int ret = wait_for_bt_irq(bt, bt->rx);
  
  			if (ret)
  				return read_count;
  
  			continue;
  		}
  
  		/* count must be multiple of packet_size */
  		if (count % packet_size != 0 ||
  		    avail % packet_size != 0) {
  			dev_warn(bt->dev, "%s(), count %zu or d %lu is not multiple of packet_size %dd\n",
  				 __func__, count, avail, packet_size);
  
  			count -= count % packet_size;
  			avail -= avail % packet_size;
  		}
  
  		if (count > avail)
  			read_size = avail;
  		else
  			read_size = count;
  
  		/* calculate continue space */
  		cont = bt->rx->buf_size - cur_read_idx;
  		if (read_size > cont)
  			read_size = cont;
  
  		if (copy_to_user(buf + cur_buf_ofs,
  				 bt->rx_packet_buf + cur_read_idx,
  				 read_size)) {
  			dev_warn(bt->dev, "%s(), copy_to_user fail\n",
  				 __func__);
  			return -EFAULT;
  		}
  
  		spin_lock_irqsave(&bt->rx_lock, flags);
  		bt->rx->packet_r += read_size / packet_size;
  		spin_unlock_irqrestore(&bt->rx_lock, flags);
  
  		read_count += read_size;
  		cur_buf_ofs += read_size;
  		count -= read_size;
  	}
  
  	/*
  	 * save current timestamp & buffer time in times_tamp and
  	 * buf_data_equivalent_time
  	 */
  	bt->rx->time_stamp = sched_clock();
  	bt->rx->buf_data_equivalent_time =
  		(unsigned long long)(bt->rx->packet_w - bt->rx->packet_r) *
  		SCO_RX_PLC_SIZE * 16 * 1000 / 2 / 64;
  	bt->rx->buf_data_equivalent_time += read_count * SCO_RX_PLC_SIZE *
  					    16 * 1000 / packet_size / 2 / 64;
  	/* return equivalent time(us) to data count */
  	bt->rx->buf_data_equivalent_time *= 1000;
  
  	return read_count;
  }
  
  static ssize_t mtk_btcvsd_snd_write(struct mtk_btcvsd_snd *bt,
  				    char __user *buf,
  				    size_t count)
  {
  	int written_size = count, avail = 0, cur_write_idx, write_size, cont;
  	unsigned int cur_buf_ofs = 0;
  	unsigned long flags;
  	unsigned int packet_size = bt->tx->packet_size;
  
  	/*
  	 * save current timestamp & buffer time in time_stamp and
  	 * buf_data_equivalent_time
  	 */
  	bt->tx->time_stamp = sched_clock();
  	bt->tx->buf_data_equivalent_time =
  		(unsigned long long)(bt->tx->packet_w - bt->tx->packet_r) *
  		packet_size * 16 * 1000 / 2 / 64;
  
  	/* return equivalent time(us) to data count */
  	bt->tx->buf_data_equivalent_time *= 1000;
  
  	while (count) {
  		spin_lock_irqsave(&bt->tx_lock, flags);
  		/* free space of TX packet buffer */
  		avail = bt->tx->buf_size -
  			(bt->tx->packet_w - bt->tx->packet_r) * packet_size;
  
  		cur_write_idx = (bt->tx->packet_w % SCO_TX_PACKER_BUF_NUM) *
  				packet_size;
  		spin_unlock_irqrestore(&bt->tx_lock, flags);
  
  		if (!avail) {
  			int ret = wait_for_bt_irq(bt, bt->rx);
  
  			if (ret)
  				return written_size;
  
  			continue;
  		}
  
  		/* count must be multiple of bt->tx->packet_size */
  		if (count % packet_size != 0 ||
  		    avail % packet_size != 0) {
  			dev_warn(bt->dev, "%s(), count %zu or avail %d is not multiple of packet_size %d\n",
  				 __func__, count, avail, packet_size);
  			count -= count % packet_size;
  			avail -= avail % packet_size;
  		}
  
  		if (count > avail)
  			write_size = avail;
  		else
  			write_size = count;
  
  		/* calculate continue space */
  		cont = bt->tx->buf_size - cur_write_idx;
  		if (write_size > cont)
  			write_size = cont;
  
  		if (copy_from_user(bt->tx_packet_buf +
  				   cur_write_idx,
  				   buf + cur_buf_ofs,
  				   write_size)) {
  			dev_warn(bt->dev, "%s(), copy_from_user fail\n",
  				 __func__);
  			return -EFAULT;
  		}
  
  		spin_lock_irqsave(&bt->tx_lock, flags);
  		bt->tx->packet_w += write_size / packet_size;
  		spin_unlock_irqrestore(&bt->tx_lock, flags);
  		cur_buf_ofs += write_size;
  		count -= write_size;
  	}
  
  	return written_size;
  }
  
  static struct mtk_btcvsd_snd_stream *get_bt_stream
  	(struct mtk_btcvsd_snd *bt, struct snd_pcm_substream *substream)
  {
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  		return bt->tx;
  	else
  		return bt->rx;
  }
  
  /* pcm ops */
  static const struct snd_pcm_hardware mtk_btcvsd_hardware = {
  	.info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
  		 SNDRV_PCM_INFO_RESUME),
  	.formats = SNDRV_PCM_FMTBIT_S16_LE,
  	.buffer_bytes_max = 24 * 1024,
  	.period_bytes_max = 24 * 1024,
  	.periods_min = 2,
  	.periods_max = 16,
  	.fifo_size = 0,
  };
  
  static int mtk_pcm_btcvsd_open(struct snd_soc_component *component,
  			       struct snd_pcm_substream *substream)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  	int ret;
  
  	dev_dbg(bt->dev, "%s(), stream %d, substream %p\n",
  		__func__, substream->stream, substream);
  
  	snd_soc_set_runtime_hwparams(substream, &mtk_btcvsd_hardware);
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		ret = mtk_btcvsd_snd_tx_init(bt);
  		bt->tx->substream = substream;
  	} else {
  		ret = mtk_btcvsd_snd_rx_init(bt);
  		bt->rx->substream = substream;
  	}
  
  	return ret;
  }
  
  static int mtk_pcm_btcvsd_close(struct snd_soc_component *component,
  				struct snd_pcm_substream *substream)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  	struct mtk_btcvsd_snd_stream *bt_stream = get_bt_stream(bt, substream);
  
  	dev_dbg(bt->dev, "%s(), stream %d\n", __func__, substream->stream);
  
  	mtk_btcvsd_snd_set_state(bt, bt_stream, BT_SCO_STATE_IDLE);
  	bt_stream->substream = NULL;
  	return 0;
  }
  
  static int mtk_pcm_btcvsd_hw_params(struct snd_soc_component *component,
  				    struct snd_pcm_substream *substream,
  				    struct snd_pcm_hw_params *hw_params)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
  	    params_buffer_bytes(hw_params) % bt->tx->packet_size != 0) {
  		dev_warn(bt->dev, "%s(), error, buffer size %d not valid\n",
  			 __func__,
  			 params_buffer_bytes(hw_params));
  		return -EINVAL;
  	}
  
  	substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
  	return 0;
  }
  
  static int mtk_pcm_btcvsd_hw_free(struct snd_soc_component *component,
  				  struct snd_pcm_substream *substream)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  		btcvsd_tx_clean_buffer(bt);
  
  	return 0;
  }
  
  static int mtk_pcm_btcvsd_prepare(struct snd_soc_component *component,
  				  struct snd_pcm_substream *substream)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  	struct mtk_btcvsd_snd_stream *bt_stream = get_bt_stream(bt, substream);
  
  	dev_dbg(bt->dev, "%s(), stream %d\n", __func__, substream->stream);
  
  	mtk_btcvsd_snd_set_state(bt, bt_stream, BT_SCO_STATE_RUNNING);
  	return 0;
  }
  
  static int mtk_pcm_btcvsd_trigger(struct snd_soc_component *component,
  				  struct snd_pcm_substream *substream, int cmd)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  	struct mtk_btcvsd_snd_stream *bt_stream = get_bt_stream(bt, substream);
  	int stream = substream->stream;
  	int hw_packet_ptr;
  
  	dev_dbg(bt->dev, "%s(), stream %d, cmd %d\n",
  		__func__, substream->stream, cmd);
  
  	switch (cmd) {
  	case SNDRV_PCM_TRIGGER_START:
  	case SNDRV_PCM_TRIGGER_RESUME:
  		hw_packet_ptr = stream == SNDRV_PCM_STREAM_PLAYBACK ?
  				bt_stream->packet_r : bt_stream->packet_w;
  		bt_stream->prev_packet_idx = hw_packet_ptr;
  		bt_stream->prev_frame = 0;
  		bt_stream->trigger_start = 1;
  		return 0;
  	case SNDRV_PCM_TRIGGER_STOP:
  	case SNDRV_PCM_TRIGGER_SUSPEND:
  		bt_stream->trigger_start = 0;
  		mtk_btcvsd_snd_set_state(bt, bt_stream, BT_SCO_STATE_ENDING);
  		return 0;
  	default:
  		return -EINVAL;
  	}
  }
  
  static snd_pcm_uframes_t mtk_pcm_btcvsd_pointer(
  	struct snd_soc_component *component,
  	struct snd_pcm_substream *substream)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  	struct mtk_btcvsd_snd_stream *bt_stream;
  	snd_pcm_uframes_t frame = 0;
  	int byte = 0;
  	int hw_packet_ptr;
  	int packet_diff;
  	spinlock_t *lock;	/* spinlock for bt stream control */
  	unsigned long flags;
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		lock = &bt->tx_lock;
  		bt_stream = bt->tx;
  	} else {
  		lock = &bt->rx_lock;
  		bt_stream = bt->rx;
  	}
  
  	spin_lock_irqsave(lock, flags);
  	hw_packet_ptr = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
  			bt->tx->packet_r : bt->rx->packet_w;
  
  	/* get packet diff from last time */
  	if (hw_packet_ptr >= bt_stream->prev_packet_idx) {
  		packet_diff = hw_packet_ptr - bt_stream->prev_packet_idx;
  	} else {
  		/* integer overflow */
  		packet_diff = (INT_MAX - bt_stream->prev_packet_idx) +
  			      (hw_packet_ptr - INT_MIN) + 1;
  	}
  	bt_stream->prev_packet_idx = hw_packet_ptr;
  
  	/* increased bytes */
  	byte = packet_diff * bt_stream->packet_size;
  
  	frame = btcvsd_bytes_to_frame(substream, byte);
  	frame += bt_stream->prev_frame;
  	frame %= substream->runtime->buffer_size;
  
  	bt_stream->prev_frame = frame;
  
  	spin_unlock_irqrestore(lock, flags);
  
  	return frame;
  }
  
  static int mtk_pcm_btcvsd_copy(struct snd_soc_component *component,
  			       struct snd_pcm_substream *substream,
  			       int channel, unsigned long pos,
  			       void __user *buf, unsigned long count)
  {
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(component);
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  		mtk_btcvsd_snd_write(bt, buf, count);
  	else
  		mtk_btcvsd_snd_read(bt, buf, count);
  
  	return 0;
  }
  
  /* kcontrol */
  static const char *const btsco_band_str[] = {"NB", "WB"};
  
  static const struct soc_enum btcvsd_enum[] = {
  	SOC_ENUM_SINGLE_EXT(ARRAY_SIZE(btsco_band_str), btsco_band_str),
  };
  
  static int btcvsd_band_get(struct snd_kcontrol *kcontrol,
  			   struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	ucontrol->value.integer.value[0] = bt->band;
  	return 0;
  }
  
  static int btcvsd_band_set(struct snd_kcontrol *kcontrol,
  			   struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
  
  	if (ucontrol->value.enumerated.item[0] >= e->items)
  		return -EINVAL;
  
  	bt->band = ucontrol->value.integer.value[0];
  	dev_dbg(bt->dev, "%s(), band %d\n", __func__, bt->band);
  	return 0;
  }
  
  static int btcvsd_loopback_get(struct snd_kcontrol *kcontrol,
  			       struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  	bool lpbk_en = bt->tx->state == BT_SCO_STATE_LOOPBACK;
  
  	ucontrol->value.integer.value[0] = lpbk_en;
  	return 0;
  }
  
  static int btcvsd_loopback_set(struct snd_kcontrol *kcontrol,
  			       struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	if (ucontrol->value.integer.value[0]) {
  		mtk_btcvsd_snd_set_state(bt, bt->tx, BT_SCO_STATE_LOOPBACK);
  		mtk_btcvsd_snd_set_state(bt, bt->rx, BT_SCO_STATE_LOOPBACK);
  	} else {
  		mtk_btcvsd_snd_set_state(bt, bt->tx, BT_SCO_STATE_RUNNING);
  		mtk_btcvsd_snd_set_state(bt, bt->rx, BT_SCO_STATE_RUNNING);
  	}
  	return 0;
  }
  
  static int btcvsd_tx_mute_get(struct snd_kcontrol *kcontrol,
  			      struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	if (!bt->tx) {
  		ucontrol->value.integer.value[0] = 0;
  		return 0;
  	}
  
  	ucontrol->value.integer.value[0] = bt->tx->mute;
  	return 0;
  }
  
  static int btcvsd_tx_mute_set(struct snd_kcontrol *kcontrol,
  			      struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	if (!bt->tx)
  		return 0;
  
  	bt->tx->mute = ucontrol->value.integer.value[0];
  	return 0;
  }
  
  static int btcvsd_rx_irq_received_get(struct snd_kcontrol *kcontrol,
  				      struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	if (!bt->rx)
  		return 0;
  
  	ucontrol->value.integer.value[0] = bt->rx->rw_cnt ? 1 : 0;
  	return 0;
  }
  
  static int btcvsd_rx_timeout_get(struct snd_kcontrol *kcontrol,
  				 struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	if (!bt->rx)
  		return 0;
  
  	ucontrol->value.integer.value[0] = bt->rx->timeout;
  	bt->rx->timeout = 0;
  	return 0;
  }
  
  static int btcvsd_rx_timestamp_get(struct snd_kcontrol *kcontrol,
  				   unsigned int __user *data, unsigned int size)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  	int ret = 0;
  	struct mtk_btcvsd_snd_time_buffer_info time_buffer_info_rx;
  
  	if (size > sizeof(struct mtk_btcvsd_snd_time_buffer_info))
  		return -EINVAL;
  
  	get_rx_time_stamp(bt, &time_buffer_info_rx);
  
  	dev_dbg(bt->dev, "%s(), time_stamp_us %llu, data_count_equi_time %llu",
  		__func__,
  		time_buffer_info_rx.time_stamp_us,
  		time_buffer_info_rx.data_count_equi_time);
  
  	if (copy_to_user(data, &time_buffer_info_rx,
  			 sizeof(struct mtk_btcvsd_snd_time_buffer_info))) {
  		dev_warn(bt->dev, "%s(), copy_to_user fail", __func__);
  		ret = -EFAULT;
  	}
  
  	return ret;
  }
  
  static int btcvsd_tx_irq_received_get(struct snd_kcontrol *kcontrol,
  				      struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	if (!bt->tx)
  		return 0;
  
  	ucontrol->value.integer.value[0] = bt->tx->rw_cnt ? 1 : 0;
  	return 0;
  }
  
  static int btcvsd_tx_timeout_get(struct snd_kcontrol *kcontrol,
  				 struct snd_ctl_elem_value *ucontrol)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  
  	ucontrol->value.integer.value[0] = bt->tx->timeout;
  	return 0;
  }
  
  static int btcvsd_tx_timestamp_get(struct snd_kcontrol *kcontrol,
  				   unsigned int __user *data, unsigned int size)
  {
  	struct snd_soc_component *cmpnt = snd_soc_kcontrol_component(kcontrol);
  	struct mtk_btcvsd_snd *bt = snd_soc_component_get_drvdata(cmpnt);
  	int ret = 0;
  	struct mtk_btcvsd_snd_time_buffer_info time_buffer_info_tx;
  
  	if (size > sizeof(struct mtk_btcvsd_snd_time_buffer_info))
  		return -EINVAL;
  
  	get_tx_time_stamp(bt, &time_buffer_info_tx);
  
  	dev_dbg(bt->dev, "%s(), time_stamp_us %llu, data_count_equi_time %llu",
  		__func__,
  		time_buffer_info_tx.time_stamp_us,
  		time_buffer_info_tx.data_count_equi_time);
  
  	if (copy_to_user(data, &time_buffer_info_tx,
  			 sizeof(struct mtk_btcvsd_snd_time_buffer_info))) {
  		dev_warn(bt->dev, "%s(), copy_to_user fail", __func__);
  		ret = -EFAULT;
  	}
  
  	return ret;
  }
  
  static const struct snd_kcontrol_new mtk_btcvsd_snd_controls[] = {
  	SOC_ENUM_EXT("BTCVSD Band", btcvsd_enum[0],
  		     btcvsd_band_get, btcvsd_band_set),
  	SOC_SINGLE_BOOL_EXT("BTCVSD Loopback Switch", 0,
  			    btcvsd_loopback_get, btcvsd_loopback_set),
  	SOC_SINGLE_BOOL_EXT("BTCVSD Tx Mute Switch", 0,
  			    btcvsd_tx_mute_get, btcvsd_tx_mute_set),
  	SOC_SINGLE_BOOL_EXT("BTCVSD Tx Irq Received Switch", 0,
  			    btcvsd_tx_irq_received_get, NULL),
  	SOC_SINGLE_BOOL_EXT("BTCVSD Tx Timeout Switch", 0,
  			    btcvsd_tx_timeout_get, NULL),
  	SOC_SINGLE_BOOL_EXT("BTCVSD Rx Irq Received Switch", 0,
  			    btcvsd_rx_irq_received_get, NULL),
  	SOC_SINGLE_BOOL_EXT("BTCVSD Rx Timeout Switch", 0,
  			    btcvsd_rx_timeout_get, NULL),
  	SND_SOC_BYTES_TLV("BTCVSD Rx Timestamp",
  			  sizeof(struct mtk_btcvsd_snd_time_buffer_info),
  			  btcvsd_rx_timestamp_get, NULL),
  	SND_SOC_BYTES_TLV("BTCVSD Tx Timestamp",
  			  sizeof(struct mtk_btcvsd_snd_time_buffer_info),
  			  btcvsd_tx_timestamp_get, NULL),
  };
  
  static int mtk_btcvsd_snd_component_probe(struct snd_soc_component *component)
  {
  	return snd_soc_add_component_controls(component,
  		mtk_btcvsd_snd_controls,
  		ARRAY_SIZE(mtk_btcvsd_snd_controls));
  }
  
  static const struct snd_soc_component_driver mtk_btcvsd_snd_platform = {
  	.name		= BTCVSD_SND_NAME,
  	.probe		= mtk_btcvsd_snd_component_probe,
  	.open		= mtk_pcm_btcvsd_open,
  	.close		= mtk_pcm_btcvsd_close,
  	.hw_params	= mtk_pcm_btcvsd_hw_params,
  	.hw_free	= mtk_pcm_btcvsd_hw_free,
  	.prepare	= mtk_pcm_btcvsd_prepare,
  	.trigger	= mtk_pcm_btcvsd_trigger,
  	.pointer	= mtk_pcm_btcvsd_pointer,
  	.copy_user	= mtk_pcm_btcvsd_copy,
  };
  
  static int mtk_btcvsd_snd_probe(struct platform_device *pdev)
  {
  	int ret = 0;
  	int irq_id;
  	u32 offset[5] = {0, 0, 0, 0, 0};
  	struct mtk_btcvsd_snd *btcvsd;
  	struct device *dev = &pdev->dev;
  
  	/* init btcvsd private data */
  	btcvsd = devm_kzalloc(dev, sizeof(*btcvsd), GFP_KERNEL);
  	if (!btcvsd)
  		return -ENOMEM;
  	platform_set_drvdata(pdev, btcvsd);
  	btcvsd->dev = dev;
  
  	/* init tx/rx */
  	btcvsd->rx = devm_kzalloc(btcvsd->dev, sizeof(*btcvsd->rx), GFP_KERNEL);
  	if (!btcvsd->rx)
  		return -ENOMEM;
  
  	btcvsd->tx = devm_kzalloc(btcvsd->dev, sizeof(*btcvsd->tx), GFP_KERNEL);
  	if (!btcvsd->tx)
  		return -ENOMEM;
  
  	spin_lock_init(&btcvsd->tx_lock);
  	spin_lock_init(&btcvsd->rx_lock);
  
  	init_waitqueue_head(&btcvsd->tx_wait);
  	init_waitqueue_head(&btcvsd->rx_wait);
  
  	mtk_btcvsd_snd_tx_init(btcvsd);
  	mtk_btcvsd_snd_rx_init(btcvsd);
  
  	/* irq */
  	irq_id = platform_get_irq(pdev, 0);
  	if (irq_id <= 0)
  		return irq_id < 0 ? irq_id : -ENXIO;
  
  	ret = devm_request_irq(dev, irq_id, mtk_btcvsd_snd_irq_handler,
  			       IRQF_TRIGGER_LOW, "BTCVSD_ISR_Handle",
  			       (void *)btcvsd);
  	if (ret) {
  		dev_err(dev, "could not request_irq for BTCVSD_ISR_Handle\n");
  		return ret;
  	}
  
  	btcvsd->irq_id = irq_id;
  
  	/* iomap */
  	btcvsd->bt_pkv_base = of_iomap(dev->of_node, 0);
  	if (!btcvsd->bt_pkv_base) {
  		dev_err(dev, "iomap bt_pkv_base fail\n");
  		return -EIO;
  	}
  
  	btcvsd->bt_sram_bank2_base = of_iomap(dev->of_node, 1);
  	if (!btcvsd->bt_sram_bank2_base) {
  		dev_err(dev, "iomap bt_sram_bank2_base fail\n");
  		return -EIO;
  	}
  
  	btcvsd->infra = syscon_regmap_lookup_by_phandle(dev->of_node,
  							"mediatek,infracfg");
  	if (IS_ERR(btcvsd->infra)) {
  		dev_err(dev, "cannot find infra controller: %ld\n",
  			PTR_ERR(btcvsd->infra));
  		return PTR_ERR(btcvsd->infra);
  	}
  
  	/* get offset */
  	ret = of_property_read_u32_array(dev->of_node, "mediatek,offset",
  					 offset,
  					 ARRAY_SIZE(offset));
  	if (ret) {
  		dev_warn(dev, "%s(), get offset fail, ret %d\n", __func__, ret);
  		return ret;
  	}
  	btcvsd->infra_misc_offset = offset[0];
  	btcvsd->conn_bt_cvsd_mask = offset[1];
  	btcvsd->cvsd_mcu_read_offset = offset[2];
  	btcvsd->cvsd_mcu_write_offset = offset[3];
  	btcvsd->cvsd_packet_indicator = offset[4];
  
  	btcvsd->bt_reg_pkt_r = btcvsd->bt_pkv_base +
  			       btcvsd->cvsd_mcu_read_offset;
  	btcvsd->bt_reg_pkt_w = btcvsd->bt_pkv_base +
  			       btcvsd->cvsd_mcu_write_offset;
  	btcvsd->bt_reg_ctl = btcvsd->bt_pkv_base +
  			     btcvsd->cvsd_packet_indicator;
  
  	/* init state */
  	mtk_btcvsd_snd_set_state(btcvsd, btcvsd->tx, BT_SCO_STATE_IDLE);
  	mtk_btcvsd_snd_set_state(btcvsd, btcvsd->rx, BT_SCO_STATE_IDLE);
  
  	return devm_snd_soc_register_component(dev, &mtk_btcvsd_snd_platform,
  					       NULL, 0);
  }
  
  static int mtk_btcvsd_snd_remove(struct platform_device *pdev)
  {
  	struct mtk_btcvsd_snd *btcvsd = dev_get_drvdata(&pdev->dev);
  
  	iounmap(btcvsd->bt_pkv_base);
  	iounmap(btcvsd->bt_sram_bank2_base);
  	return 0;
  }
  
  static const struct of_device_id mtk_btcvsd_snd_dt_match[] = {
  	{ .compatible = "mediatek,mtk-btcvsd-snd", },
  	{},
  };
  MODULE_DEVICE_TABLE(of, mtk_btcvsd_snd_dt_match);
  
  static struct platform_driver mtk_btcvsd_snd_driver = {
  	.driver = {
  		.name = "mtk-btcvsd-snd",
  		.of_match_table = mtk_btcvsd_snd_dt_match,
  	},
  	.probe = mtk_btcvsd_snd_probe,
  	.remove = mtk_btcvsd_snd_remove,
  };
  
  module_platform_driver(mtk_btcvsd_snd_driver);
  
  MODULE_DESCRIPTION("Mediatek ALSA BT SCO CVSD/MSBC Driver");
  MODULE_AUTHOR("KaiChieh Chuang <kaichieh.chuang@mediatek.com>");
  MODULE_LICENSE("GPL v2");
  