// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
  // Copyright(c) 2015-17 Intel Corporation.
  
  /*
   * Cadence SoundWire Master module
   * Used by Master driver
   */
  
  #include <linux/delay.h>
  #include <linux/device.h>

  #include <linux/debugfs.h>

  #include <linux/interrupt.h>

  #include <linux/io.h>

  #include <linux/module.h>
  #include <linux/mod_devicetable.h>

  #include <linux/pm_runtime.h>

  #include <linux/soundwire/sdw_registers.h>
  #include <linux/soundwire/sdw.h>

  #include <sound/pcm_params.h>
  #include <sound/soc.h>

  #include <linux/workqueue.h>

  #include "bus.h"
  #include "cadence_master.h"

  static int interrupt_mask;
  module_param_named(cnds_mcp_int_mask, interrupt_mask, int, 0444);
  MODULE_PARM_DESC(cdns_mcp_int_mask, "Cadence MCP IntMask");

  #define CDNS_MCP_CONFIG				0x0
  
  #define CDNS_MCP_CONFIG_MCMD_RETRY		GENMASK(27, 24)
  #define CDNS_MCP_CONFIG_MPREQ_DELAY		GENMASK(20, 16)
  #define CDNS_MCP_CONFIG_MMASTER			BIT(7)
  #define CDNS_MCP_CONFIG_BUS_REL			BIT(6)
  #define CDNS_MCP_CONFIG_SNIFFER			BIT(5)
  #define CDNS_MCP_CONFIG_SSPMOD			BIT(4)
  #define CDNS_MCP_CONFIG_CMD			BIT(3)
  #define CDNS_MCP_CONFIG_OP			GENMASK(2, 0)
  #define CDNS_MCP_CONFIG_OP_NORMAL		0
  
  #define CDNS_MCP_CONTROL			0x4
  
  #define CDNS_MCP_CONTROL_RST_DELAY		GENMASK(10, 8)
  #define CDNS_MCP_CONTROL_CMD_RST		BIT(7)
  #define CDNS_MCP_CONTROL_SOFT_RST		BIT(6)
  #define CDNS_MCP_CONTROL_SW_RST			BIT(5)
  #define CDNS_MCP_CONTROL_HW_RST			BIT(4)
  #define CDNS_MCP_CONTROL_CLK_PAUSE		BIT(3)
  #define CDNS_MCP_CONTROL_CLK_STOP_CLR		BIT(2)
  #define CDNS_MCP_CONTROL_CMD_ACCEPT		BIT(1)
  #define CDNS_MCP_CONTROL_BLOCK_WAKEUP		BIT(0)

  #define CDNS_MCP_CMDCTRL			0x8

  
  #define CDNS_MCP_CMDCTRL_INSERT_PARITY_ERR	BIT(2)

  #define CDNS_MCP_SSPSTAT			0xC
  #define CDNS_MCP_FRAME_SHAPE			0x10
  #define CDNS_MCP_FRAME_SHAPE_INIT		0x14

  #define CDNS_MCP_FRAME_SHAPE_COL_MASK		GENMASK(2, 0)

  #define CDNS_MCP_FRAME_SHAPE_ROW_MASK		GENMASK(7, 3)

  
  #define CDNS_MCP_CONFIG_UPDATE			0x18
  #define CDNS_MCP_CONFIG_UPDATE_BIT		BIT(0)
  
  #define CDNS_MCP_PHYCTRL			0x1C
  #define CDNS_MCP_SSP_CTRL0			0x20
  #define CDNS_MCP_SSP_CTRL1			0x28
  #define CDNS_MCP_CLK_CTRL0			0x30
  #define CDNS_MCP_CLK_CTRL1			0x38

  #define CDNS_MCP_CLK_MCLKD_MASK		GENMASK(7, 0)

  
  #define CDNS_MCP_STAT				0x40
  
  #define CDNS_MCP_STAT_ACTIVE_BANK		BIT(20)
  #define CDNS_MCP_STAT_CLK_STOP			BIT(16)
  
  #define CDNS_MCP_INTSTAT			0x44
  #define CDNS_MCP_INTMASK			0x48
  
  #define CDNS_MCP_INT_IRQ			BIT(31)

  #define CDNS_MCP_INT_RESERVED1			GENMASK(30, 17)

  #define CDNS_MCP_INT_WAKEUP			BIT(16)
  #define CDNS_MCP_INT_SLAVE_RSVD			BIT(15)
  #define CDNS_MCP_INT_SLAVE_ALERT		BIT(14)
  #define CDNS_MCP_INT_SLAVE_ATTACH		BIT(13)
  #define CDNS_MCP_INT_SLAVE_NATTACH		BIT(12)
  #define CDNS_MCP_INT_SLAVE_MASK			GENMASK(15, 12)
  #define CDNS_MCP_INT_DPINT			BIT(11)
  #define CDNS_MCP_INT_CTRL_CLASH			BIT(10)
  #define CDNS_MCP_INT_DATA_CLASH			BIT(9)

  #define CDNS_MCP_INT_PARITY			BIT(8)

  #define CDNS_MCP_INT_CMD_ERR			BIT(7)

  #define CDNS_MCP_INT_RESERVED2			GENMASK(6, 4)

  #define CDNS_MCP_INT_RX_NE			BIT(3)

  #define CDNS_MCP_INT_RX_WL			BIT(2)
  #define CDNS_MCP_INT_TXE			BIT(1)

  #define CDNS_MCP_INT_TXF			BIT(0)

  #define CDNS_MCP_INT_RESERVED (CDNS_MCP_INT_RESERVED1 | CDNS_MCP_INT_RESERVED2)

  
  #define CDNS_MCP_INTSET				0x4C

  #define CDNS_MCP_SLAVE_STAT			0x50
  #define CDNS_MCP_SLAVE_STAT_MASK		GENMASK(1, 0)

  
  #define CDNS_MCP_SLAVE_INTSTAT0			0x54
  #define CDNS_MCP_SLAVE_INTSTAT1			0x58
  #define CDNS_MCP_SLAVE_INTSTAT_NPRESENT		BIT(0)
  #define CDNS_MCP_SLAVE_INTSTAT_ATTACHED		BIT(1)
  #define CDNS_MCP_SLAVE_INTSTAT_ALERT		BIT(2)
  #define CDNS_MCP_SLAVE_INTSTAT_RESERVED		BIT(3)
  #define CDNS_MCP_SLAVE_STATUS_BITS		GENMASK(3, 0)
  #define CDNS_MCP_SLAVE_STATUS_NUM		4
  
  #define CDNS_MCP_SLAVE_INTMASK0			0x5C
  #define CDNS_MCP_SLAVE_INTMASK1			0x60

  #define CDNS_MCP_SLAVE_INTMASK0_MASK		GENMASK(31, 0)
  #define CDNS_MCP_SLAVE_INTMASK1_MASK		GENMASK(15, 0)

  
  #define CDNS_MCP_PORT_INTSTAT			0x64
  #define CDNS_MCP_PDI_STAT			0x6C
  
  #define CDNS_MCP_FIFOLEVEL			0x78
  #define CDNS_MCP_FIFOSTAT			0x7C
  #define CDNS_MCP_RX_FIFO_AVAIL			GENMASK(5, 0)
  
  #define CDNS_MCP_CMD_BASE			0x80
  #define CDNS_MCP_RESP_BASE			0x80
  #define CDNS_MCP_CMD_LEN			0x20
  #define CDNS_MCP_CMD_WORD_LEN			0x4
  
  #define CDNS_MCP_CMD_SSP_TAG			BIT(31)
  #define CDNS_MCP_CMD_COMMAND			GENMASK(30, 28)
  #define CDNS_MCP_CMD_DEV_ADDR			GENMASK(27, 24)

  #define CDNS_MCP_CMD_REG_ADDR			GENMASK(23, 8)

  #define CDNS_MCP_CMD_REG_DATA			GENMASK(7, 0)
  
  #define CDNS_MCP_CMD_READ			2
  #define CDNS_MCP_CMD_WRITE			3
  
  #define CDNS_MCP_RESP_RDATA			GENMASK(15, 8)
  #define CDNS_MCP_RESP_ACK			BIT(0)
  #define CDNS_MCP_RESP_NACK			BIT(1)
  
  #define CDNS_DP_SIZE				128
  
  #define CDNS_DPN_B0_CONFIG(n)			(0x100 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B0_CH_EN(n)			(0x104 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B0_SAMPLE_CTRL(n)		(0x108 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B0_OFFSET_CTRL(n)		(0x10C + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B0_HCTRL(n)			(0x110 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B0_ASYNC_CTRL(n)		(0x114 + CDNS_DP_SIZE * (n))
  
  #define CDNS_DPN_B1_CONFIG(n)			(0x118 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B1_CH_EN(n)			(0x11C + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B1_SAMPLE_CTRL(n)		(0x120 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B1_OFFSET_CTRL(n)		(0x124 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B1_HCTRL(n)			(0x128 + CDNS_DP_SIZE * (n))
  #define CDNS_DPN_B1_ASYNC_CTRL(n)		(0x12C + CDNS_DP_SIZE * (n))
  
  #define CDNS_DPN_CONFIG_BPM			BIT(18)
  #define CDNS_DPN_CONFIG_BGC			GENMASK(17, 16)
  #define CDNS_DPN_CONFIG_WL			GENMASK(12, 8)
  #define CDNS_DPN_CONFIG_PORT_DAT		GENMASK(3, 2)
  #define CDNS_DPN_CONFIG_PORT_FLOW		GENMASK(1, 0)
  
  #define CDNS_DPN_SAMPLE_CTRL_SI			GENMASK(15, 0)
  
  #define CDNS_DPN_OFFSET_CTRL_1			GENMASK(7, 0)
  #define CDNS_DPN_OFFSET_CTRL_2			GENMASK(15, 8)
  
  #define CDNS_DPN_HCTRL_HSTOP			GENMASK(3, 0)
  #define CDNS_DPN_HCTRL_HSTART			GENMASK(7, 4)
  #define CDNS_DPN_HCTRL_LCTRL			GENMASK(10, 8)
  
  #define CDNS_PORTCTRL				0x130

  #define CDNS_PORTCTRL_TEST_FAILED		BIT(1)

  #define CDNS_PORTCTRL_DIRN			BIT(7)
  #define CDNS_PORTCTRL_BANK_INVERT		BIT(8)
  
  #define CDNS_PORT_OFFSET			0x80
  
  #define CDNS_PDI_CONFIG(n)			(0x1100 + (n) * 16)
  
  #define CDNS_PDI_CONFIG_SOFT_RESET		BIT(24)
  #define CDNS_PDI_CONFIG_CHANNEL			GENMASK(15, 8)
  #define CDNS_PDI_CONFIG_PORT			GENMASK(4, 0)
  
  /* Driver defaults */

  #define CDNS_TX_TIMEOUT				2000

  #define CDNS_SCP_RX_FIFOLEVEL			0x2
  
  /*
   * register accessor helpers
   */
  static inline u32 cdns_readl(struct sdw_cdns *cdns, int offset)
  {
  	return readl(cdns->registers + offset);
  }
  
  static inline void cdns_writel(struct sdw_cdns *cdns, int offset, u32 value)
  {
  	writel(value, cdns->registers + offset);
  }
  
  static inline void cdns_updatel(struct sdw_cdns *cdns,
  				int offset, u32 mask, u32 val)
  {
  	u32 tmp;
  
  	tmp = cdns_readl(cdns, offset);
  	tmp = (tmp & ~mask) | val;
  	cdns_writel(cdns, offset, tmp);
  }

  static int cdns_set_wait(struct sdw_cdns *cdns, int offset, u32 mask, u32 value)
  {
  	int timeout = 10;
  	u32 reg_read;
  
  	/* Wait for bit to be set */
  	do {
  		reg_read = readl(cdns->registers + offset);
  		if ((reg_read & mask) == value)
  			return 0;
  
  		timeout--;
  		usleep_range(50, 100);
  	} while (timeout != 0);
  
  	return -ETIMEDOUT;
  }

  static int cdns_clear_bit(struct sdw_cdns *cdns, int offset, u32 value)
  {
  	writel(value, cdns->registers + offset);
  
  	/* Wait for bit to be self cleared */
  	return cdns_set_wait(cdns, offset, value, 0);
  }

  /*

   * all changes to the MCP_CONFIG, MCP_CONTROL, MCP_CMDCTRL and MCP_PHYCTRL
   * need to be confirmed with a write to MCP_CONFIG_UPDATE
   */

  static int cdns_config_update(struct sdw_cdns *cdns)

  {
  	int ret;

  	if (sdw_cdns_is_clock_stop(cdns)) {
  		dev_err(cdns->dev, "Cannot program MCP_CONFIG_UPDATE in ClockStopMode
  ");
  		return -EINVAL;
  	}

  	ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE,
  			     CDNS_MCP_CONFIG_UPDATE_BIT);
  	if (ret < 0)
  		dev_err(cdns->dev, "Config update timedout
  ");
  
  	return ret;
  }
  
  /*

   * debugfs
   */
  #ifdef CONFIG_DEBUG_FS
  
  #define RD_BUF (2 * PAGE_SIZE)
  
  static ssize_t cdns_sprintf(struct sdw_cdns *cdns,
  			    char *buf, size_t pos, unsigned int reg)
  {
  	return scnprintf(buf + pos, RD_BUF - pos,
  			 "%4x\t%8x
  ", reg, cdns_readl(cdns, reg));
  }
  
  static int cdns_reg_show(struct seq_file *s, void *data)
  {
  	struct sdw_cdns *cdns = s->private;
  	char *buf;
  	ssize_t ret;
  	int num_ports;
  	int i, j;
  
  	buf = kzalloc(RD_BUF, GFP_KERNEL);
  	if (!buf)
  		return -ENOMEM;
  
  	ret = scnprintf(buf, RD_BUF, "Register  Value
  ");
  	ret += scnprintf(buf + ret, RD_BUF - ret, "
  MCP Registers
  ");
  	/* 8 MCP registers */
  	for (i = CDNS_MCP_CONFIG; i <= CDNS_MCP_PHYCTRL; i += sizeof(u32))
  		ret += cdns_sprintf(cdns, buf, ret, i);
  
  	ret += scnprintf(buf + ret, RD_BUF - ret,
  			 "
  Status & Intr Registers
  ");
  	/* 13 Status & Intr registers (offsets 0x70 and 0x74 not defined) */
  	for (i = CDNS_MCP_STAT; i <=  CDNS_MCP_FIFOSTAT; i += sizeof(u32))
  		ret += cdns_sprintf(cdns, buf, ret, i);
  
  	ret += scnprintf(buf + ret, RD_BUF - ret,
  			 "
  SSP & Clk ctrl Registers
  ");
  	ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_SSP_CTRL0);
  	ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_SSP_CTRL1);
  	ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_CLK_CTRL0);
  	ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_CLK_CTRL1);
  
  	ret += scnprintf(buf + ret, RD_BUF - ret,
  			 "
  DPn B0 Registers
  ");

  	num_ports = cdns->num_ports;

  
  	for (i = 0; i < num_ports; i++) {
  		ret += scnprintf(buf + ret, RD_BUF - ret,
  				 "
  DP-%d
  ", i);
  		for (j = CDNS_DPN_B0_CONFIG(i);
  		     j < CDNS_DPN_B0_ASYNC_CTRL(i); j += sizeof(u32))
  			ret += cdns_sprintf(cdns, buf, ret, j);
  	}
  
  	ret += scnprintf(buf + ret, RD_BUF - ret,
  			 "
  DPn B1 Registers
  ");
  	for (i = 0; i < num_ports; i++) {
  		ret += scnprintf(buf + ret, RD_BUF - ret,
  				 "
  DP-%d
  ", i);
  
  		for (j = CDNS_DPN_B1_CONFIG(i);
  		     j < CDNS_DPN_B1_ASYNC_CTRL(i); j += sizeof(u32))
  			ret += cdns_sprintf(cdns, buf, ret, j);
  	}
  
  	ret += scnprintf(buf + ret, RD_BUF - ret,
  			 "
  DPn Control Registers
  ");
  	for (i = 0; i < num_ports; i++)
  		ret += cdns_sprintf(cdns, buf, ret,
  				CDNS_PORTCTRL + i * CDNS_PORT_OFFSET);
  
  	ret += scnprintf(buf + ret, RD_BUF - ret,
  			 "
  PDIn Config Registers
  ");
  
  	/* number of PDI and ports is interchangeable */
  	for (i = 0; i < num_ports; i++)
  		ret += cdns_sprintf(cdns, buf, ret, CDNS_PDI_CONFIG(i));
  
  	seq_printf(s, "%s", buf);
  	kfree(buf);
  
  	return 0;
  }
  DEFINE_SHOW_ATTRIBUTE(cdns_reg);

  static int cdns_hw_reset(void *data, u64 value)
  {
  	struct sdw_cdns *cdns = data;
  	int ret;
  
  	if (value != 1)
  		return -EINVAL;
  
  	/* Userspace changed the hardware state behind the kernel's back */
  	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
  
  	ret = sdw_cdns_exit_reset(cdns);
  
  	dev_dbg(cdns->dev, "link hw_reset done: %d
  ", ret);
  
  	return ret;
  }
  
  DEFINE_DEBUGFS_ATTRIBUTE(cdns_hw_reset_fops, NULL, cdns_hw_reset, "%llu
  ");

  static int cdns_parity_error_injection(void *data, u64 value)
  {
  	struct sdw_cdns *cdns = data;
  	struct sdw_bus *bus;
  	int ret;
  
  	if (value != 1)
  		return -EINVAL;
  
  	bus = &cdns->bus;
  
  	/*
  	 * Resume Master device. If this results in a bus reset, the
  	 * Slave devices will re-attach and be re-enumerated.
  	 */
  	ret = pm_runtime_get_sync(bus->dev);
  	if (ret < 0 && ret != -EACCES) {
  		dev_err_ratelimited(cdns->dev,
  				    "pm_runtime_get_sync failed in %s, ret %d
  ",
  				    __func__, ret);
  		pm_runtime_put_noidle(bus->dev);
  		return ret;
  	}
  
  	/*
  	 * wait long enough for Slave(s) to be in steady state. This
  	 * does not need to be super precise.
  	 */
  	msleep(200);
  
  	/*
  	 * Take the bus lock here to make sure that any bus transactions
  	 * will be queued while we inject a parity error on a dummy read
  	 */
  	mutex_lock(&bus->bus_lock);
  
  	/* program hardware to inject parity error */
  	cdns_updatel(cdns, CDNS_MCP_CMDCTRL,
  		     CDNS_MCP_CMDCTRL_INSERT_PARITY_ERR,
  		     CDNS_MCP_CMDCTRL_INSERT_PARITY_ERR);
  
  	/* commit changes */
  	cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE,
  		     CDNS_MCP_CONFIG_UPDATE_BIT,
  		     CDNS_MCP_CONFIG_UPDATE_BIT);
  
  	/* do a broadcast dummy read to avoid bus clashes */
  	ret = sdw_bread_no_pm_unlocked(&cdns->bus, 0xf, SDW_SCP_DEVID_0);
  	dev_info(cdns->dev, "parity error injection, read: %d
  ", ret);
  
  	/* program hardware to disable parity error */
  	cdns_updatel(cdns, CDNS_MCP_CMDCTRL,
  		     CDNS_MCP_CMDCTRL_INSERT_PARITY_ERR,
  		     0);
  
  	/* commit changes */
  	cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE,
  		     CDNS_MCP_CONFIG_UPDATE_BIT,
  		     CDNS_MCP_CONFIG_UPDATE_BIT);
  
  	/* Continue bus operation with parity error injection disabled */
  	mutex_unlock(&bus->bus_lock);
  
  	/* Userspace changed the hardware state behind the kernel's back */
  	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
  
  	/*
  	 * allow Master device to enter pm_runtime suspend. This may
  	 * also result in Slave devices suspending.
  	 */
  	pm_runtime_mark_last_busy(bus->dev);
  	pm_runtime_put_autosuspend(bus->dev);
  
  	return 0;
  }
  
  DEFINE_DEBUGFS_ATTRIBUTE(cdns_parity_error_fops, NULL,
  			 cdns_parity_error_injection, "%llu
  ");

  /**
   * sdw_cdns_debugfs_init() - Cadence debugfs init
   * @cdns: Cadence instance
   * @root: debugfs root
   */
  void sdw_cdns_debugfs_init(struct sdw_cdns *cdns, struct dentry *root)
  {
  	debugfs_create_file("cdns-registers", 0400, root, cdns, &cdns_reg_fops);

  
  	debugfs_create_file("cdns-hw-reset", 0200, root, cdns,
  			    &cdns_hw_reset_fops);

  
  	debugfs_create_file("cdns-parity-error-injection", 0200, root, cdns,
  			    &cdns_parity_error_fops);

  }
  EXPORT_SYMBOL_GPL(sdw_cdns_debugfs_init);
  
  #endif /* CONFIG_DEBUG_FS */
  
  /*

   * IO Calls
   */

  static enum sdw_command_response
  cdns_fill_msg_resp(struct sdw_cdns *cdns,
  		   struct sdw_msg *msg, int count, int offset)

  {
  	int nack = 0, no_ack = 0;
  	int i;
  
  	/* check message response */
  	for (i = 0; i < count; i++) {
  		if (!(cdns->response_buf[i] & CDNS_MCP_RESP_ACK)) {
  			no_ack = 1;

  			dev_dbg_ratelimited(cdns->dev, "Msg Ack not received
  ");

  			if (cdns->response_buf[i] & CDNS_MCP_RESP_NACK) {
  				nack = 1;

  				dev_err_ratelimited(cdns->dev, "Msg NACK received
  ");

  			}
  		}
  	}
  
  	if (nack) {

  		dev_err_ratelimited(cdns->dev, "Msg NACKed for Slave %d
  ", msg->dev_num);

  		return SDW_CMD_FAIL;

  	}
  
  	if (no_ack) {

  		dev_dbg_ratelimited(cdns->dev, "Msg ignored for Slave %d
  ", msg->dev_num);

  		return SDW_CMD_IGNORED;
  	}
  
  	/* fill response */
  	for (i = 0; i < count; i++)

  		msg->buf[i + offset] = FIELD_GET(CDNS_MCP_RESP_RDATA, cdns->response_buf[i]);

  
  	return SDW_CMD_OK;
  }
  
  static enum sdw_command_response
  _cdns_xfer_msg(struct sdw_cdns *cdns, struct sdw_msg *msg, int cmd,

  	       int offset, int count, bool defer)

  {
  	unsigned long time;
  	u32 base, i, data;
  	u16 addr;
  
  	/* Program the watermark level for RX FIFO */
  	if (cdns->msg_count != count) {
  		cdns_writel(cdns, CDNS_MCP_FIFOLEVEL, count);
  		cdns->msg_count = count;
  	}
  
  	base = CDNS_MCP_CMD_BASE;
  	addr = msg->addr;
  
  	for (i = 0; i < count; i++) {

  		data = FIELD_PREP(CDNS_MCP_CMD_DEV_ADDR, msg->dev_num);
  		data |= FIELD_PREP(CDNS_MCP_CMD_COMMAND, cmd);
  		data |= FIELD_PREP(CDNS_MCP_CMD_REG_ADDR, addr);
  		addr++;

  
  		if (msg->flags == SDW_MSG_FLAG_WRITE)
  			data |= msg->buf[i + offset];

  		data |= FIELD_PREP(CDNS_MCP_CMD_SSP_TAG, msg->ssp_sync);

  		cdns_writel(cdns, base, data);
  		base += CDNS_MCP_CMD_WORD_LEN;
  	}
  
  	if (defer)
  		return SDW_CMD_OK;
  
  	/* wait for timeout or response */
  	time = wait_for_completion_timeout(&cdns->tx_complete,

  					   msecs_to_jiffies(CDNS_TX_TIMEOUT));

  	if (!time) {

  		dev_err(cdns->dev, "IO transfer timed out, cmd %d device %d addr %x len %d
  ",
  			cmd, msg->dev_num, msg->addr, msg->len);

  		msg->len = 0;
  		return SDW_CMD_TIMEOUT;
  	}
  
  	return cdns_fill_msg_resp(cdns, msg, count, offset);
  }

  static enum sdw_command_response
  cdns_program_scp_addr(struct sdw_cdns *cdns, struct sdw_msg *msg)

  {
  	int nack = 0, no_ack = 0;
  	unsigned long time;
  	u32 data[2], base;
  	int i;
  
  	/* Program the watermark level for RX FIFO */
  	if (cdns->msg_count != CDNS_SCP_RX_FIFOLEVEL) {
  		cdns_writel(cdns, CDNS_MCP_FIFOLEVEL, CDNS_SCP_RX_FIFOLEVEL);
  		cdns->msg_count = CDNS_SCP_RX_FIFOLEVEL;
  	}

  	data[0] = FIELD_PREP(CDNS_MCP_CMD_DEV_ADDR, msg->dev_num);
  	data[0] |= FIELD_PREP(CDNS_MCP_CMD_COMMAND, 0x3);

  	data[1] = data[0];

  	data[0] |= FIELD_PREP(CDNS_MCP_CMD_REG_ADDR, SDW_SCP_ADDRPAGE1);
  	data[1] |= FIELD_PREP(CDNS_MCP_CMD_REG_ADDR, SDW_SCP_ADDRPAGE2);

  
  	data[0] |= msg->addr_page1;
  	data[1] |= msg->addr_page2;
  
  	base = CDNS_MCP_CMD_BASE;
  	cdns_writel(cdns, base, data[0]);
  	base += CDNS_MCP_CMD_WORD_LEN;
  	cdns_writel(cdns, base, data[1]);
  
  	time = wait_for_completion_timeout(&cdns->tx_complete,

  					   msecs_to_jiffies(CDNS_TX_TIMEOUT));

  	if (!time) {
  		dev_err(cdns->dev, "SCP Msg trf timed out
  ");
  		msg->len = 0;
  		return SDW_CMD_TIMEOUT;
  	}
  
  	/* check response the writes */
  	for (i = 0; i < 2; i++) {
  		if (!(cdns->response_buf[i] & CDNS_MCP_RESP_ACK)) {
  			no_ack = 1;

  			dev_err(cdns->dev, "Program SCP Ack not received
  ");

  			if (cdns->response_buf[i] & CDNS_MCP_RESP_NACK) {
  				nack = 1;

  				dev_err(cdns->dev, "Program SCP NACK received
  ");

  			}
  		}
  	}
  
  	/* For NACK, NO ack, don't return err if we are in Broadcast mode */
  	if (nack) {

  		dev_err_ratelimited(cdns->dev,
  				    "SCP_addrpage NACKed for Slave %d
  ", msg->dev_num);

  		return SDW_CMD_FAIL;

  	}
  
  	if (no_ack) {

  		dev_dbg_ratelimited(cdns->dev,
  				    "SCP_addrpage ignored for Slave %d
  ", msg->dev_num);

  		return SDW_CMD_IGNORED;
  	}
  
  	return SDW_CMD_OK;
  }
  
  static int cdns_prep_msg(struct sdw_cdns *cdns, struct sdw_msg *msg, int *cmd)
  {
  	int ret;
  
  	if (msg->page) {
  		ret = cdns_program_scp_addr(cdns, msg);
  		if (ret) {
  			msg->len = 0;
  			return ret;
  		}
  	}
  
  	switch (msg->flags) {
  	case SDW_MSG_FLAG_READ:
  		*cmd = CDNS_MCP_CMD_READ;
  		break;
  
  	case SDW_MSG_FLAG_WRITE:
  		*cmd = CDNS_MCP_CMD_WRITE;
  		break;
  
  	default:
  		dev_err(cdns->dev, "Invalid msg cmd: %d
  ", msg->flags);
  		return -EINVAL;
  	}
  
  	return 0;
  }

  enum sdw_command_response

  cdns_xfer_msg(struct sdw_bus *bus, struct sdw_msg *msg)
  {
  	struct sdw_cdns *cdns = bus_to_cdns(bus);
  	int cmd = 0, ret, i;
  
  	ret = cdns_prep_msg(cdns, msg, &cmd);
  	if (ret)
  		return SDW_CMD_FAIL_OTHER;
  
  	for (i = 0; i < msg->len / CDNS_MCP_CMD_LEN; i++) {
  		ret = _cdns_xfer_msg(cdns, msg, cmd, i * CDNS_MCP_CMD_LEN,

  				     CDNS_MCP_CMD_LEN, false);

  		if (ret < 0)
  			goto exit;
  	}
  
  	if (!(msg->len % CDNS_MCP_CMD_LEN))
  		goto exit;
  
  	ret = _cdns_xfer_msg(cdns, msg, cmd, i * CDNS_MCP_CMD_LEN,

  			     msg->len % CDNS_MCP_CMD_LEN, false);

  
  exit:
  	return ret;
  }

  EXPORT_SYMBOL(cdns_xfer_msg);

  enum sdw_command_response

  cdns_xfer_msg_defer(struct sdw_bus *bus,

  		    struct sdw_msg *msg, struct sdw_defer *defer)

  {
  	struct sdw_cdns *cdns = bus_to_cdns(bus);
  	int cmd = 0, ret;
  
  	/* for defer only 1 message is supported */
  	if (msg->len > 1)
  		return -ENOTSUPP;
  
  	ret = cdns_prep_msg(cdns, msg, &cmd);
  	if (ret)
  		return SDW_CMD_FAIL_OTHER;
  
  	cdns->defer = defer;
  	cdns->defer->length = msg->len;
  
  	return _cdns_xfer_msg(cdns, msg, cmd, 0, msg->len, true);
  }

  EXPORT_SYMBOL(cdns_xfer_msg_defer);

  enum sdw_command_response

  cdns_reset_page_addr(struct sdw_bus *bus, unsigned int dev_num)
  {
  	struct sdw_cdns *cdns = bus_to_cdns(bus);
  	struct sdw_msg msg;
  
  	/* Create dummy message with valid device number */
  	memset(&msg, 0, sizeof(msg));
  	msg.dev_num = dev_num;
  
  	return cdns_program_scp_addr(cdns, &msg);
  }

  EXPORT_SYMBOL(cdns_reset_page_addr);

  
  /*

   * IRQ handling
   */

  static void cdns_read_response(struct sdw_cdns *cdns)
  {
  	u32 num_resp, cmd_base;
  	int i;
  
  	num_resp = cdns_readl(cdns, CDNS_MCP_FIFOSTAT);
  	num_resp &= CDNS_MCP_RX_FIFO_AVAIL;
  
  	cmd_base = CDNS_MCP_CMD_BASE;
  
  	for (i = 0; i < num_resp; i++) {
  		cdns->response_buf[i] = cdns_readl(cdns, cmd_base);
  		cmd_base += CDNS_MCP_CMD_WORD_LEN;
  	}
  }

  static int cdns_update_slave_status(struct sdw_cdns *cdns,

  				    u32 slave0, u32 slave1)

  {
  	enum sdw_slave_status status[SDW_MAX_DEVICES + 1];
  	bool is_slave = false;

  	u64 slave;
  	u32 mask;

  	int i, set_status;
  
  	/* combine the two status */
  	slave = ((u64)slave1 << 32) | slave0;
  	memset(status, 0, sizeof(status));
  
  	for (i = 0; i <= SDW_MAX_DEVICES; i++) {
  		mask = (slave >> (i * CDNS_MCP_SLAVE_STATUS_NUM)) &
  				CDNS_MCP_SLAVE_STATUS_BITS;
  		if (!mask)
  			continue;
  
  		is_slave = true;
  		set_status = 0;
  
  		if (mask & CDNS_MCP_SLAVE_INTSTAT_RESERVED) {
  			status[i] = SDW_SLAVE_RESERVED;
  			set_status++;
  		}
  
  		if (mask & CDNS_MCP_SLAVE_INTSTAT_ATTACHED) {
  			status[i] = SDW_SLAVE_ATTACHED;
  			set_status++;
  		}
  
  		if (mask & CDNS_MCP_SLAVE_INTSTAT_ALERT) {
  			status[i] = SDW_SLAVE_ALERT;
  			set_status++;
  		}
  
  		if (mask & CDNS_MCP_SLAVE_INTSTAT_NPRESENT) {
  			status[i] = SDW_SLAVE_UNATTACHED;
  			set_status++;
  		}
  
  		/* first check if Slave reported multiple status */
  		if (set_status > 1) {

  			u32 val;

  			dev_warn_ratelimited(cdns->dev,

  					     "Slave %d reported multiple Status: %d
  ",
  					     i, mask);
  
  			/* check latest status extracted from PING commands */
  			val = cdns_readl(cdns, CDNS_MCP_SLAVE_STAT);
  			val >>= (i * 2);
  
  			switch (val & 0x3) {
  			case 0:
  				status[i] = SDW_SLAVE_UNATTACHED;
  				break;
  			case 1:
  				status[i] = SDW_SLAVE_ATTACHED;
  				break;
  			case 2:
  				status[i] = SDW_SLAVE_ALERT;
  				break;
  			case 3:
  			default:
  				status[i] = SDW_SLAVE_RESERVED;
  				break;
  			}
  
  			dev_warn_ratelimited(cdns->dev,
  					     "Slave %d status updated to %d
  ",
  					     i, status[i]);

  		}
  	}
  
  	if (is_slave)
  		return sdw_handle_slave_status(&cdns->bus, status);
  
  	return 0;
  }
  
  /**
   * sdw_cdns_irq() - Cadence interrupt handler
   * @irq: irq number
   * @dev_id: irq context
   */
  irqreturn_t sdw_cdns_irq(int irq, void *dev_id)
  {
  	struct sdw_cdns *cdns = dev_id;
  	u32 int_status;
  	int ret = IRQ_HANDLED;
  
  	/* Check if the link is up */
  	if (!cdns->link_up)
  		return IRQ_NONE;
  
  	int_status = cdns_readl(cdns, CDNS_MCP_INTSTAT);

  	/* check for reserved values read as zero */
  	if (int_status & CDNS_MCP_INT_RESERVED)
  		return IRQ_NONE;

  	if (!(int_status & CDNS_MCP_INT_IRQ))
  		return IRQ_NONE;

  	if (int_status & CDNS_MCP_INT_RX_WL) {
  		cdns_read_response(cdns);
  
  		if (cdns->defer) {
  			cdns_fill_msg_resp(cdns, cdns->defer->msg,

  					   cdns->defer->length, 0);

  			complete(&cdns->defer->complete);
  			cdns->defer = NULL;

  		} else {

  			complete(&cdns->tx_complete);

  		}

  	}

  	if (int_status & CDNS_MCP_INT_PARITY) {
  		/* Parity error detected by Master */
  		dev_err_ratelimited(cdns->dev, "Parity error
  ");
  	}

  	if (int_status & CDNS_MCP_INT_CTRL_CLASH) {

  		/* Slave is driving bit slot during control word */
  		dev_err_ratelimited(cdns->dev, "Bus clash for control word
  ");

  	}
  
  	if (int_status & CDNS_MCP_INT_DATA_CLASH) {
  		/*
  		 * Multiple slaves trying to drive bit slot, or issue with
  		 * ownership of data bits or Slave gone bonkers
  		 */
  		dev_err_ratelimited(cdns->dev, "Bus clash for data word
  ");

  	}

  	if (cdns->bus.params.m_data_mode != SDW_PORT_DATA_MODE_NORMAL &&
  	    int_status & CDNS_MCP_INT_DPINT) {
  		u32 port_intstat;
  
  		/* just log which ports report an error */
  		port_intstat = cdns_readl(cdns, CDNS_MCP_PORT_INTSTAT);
  		dev_err_ratelimited(cdns->dev, "DP interrupt: PortIntStat %8x
  ",
  				    port_intstat);
  
  		/* clear status w/ write1 */
  		cdns_writel(cdns, CDNS_MCP_PORT_INTSTAT, port_intstat);
  	}

  	if (int_status & CDNS_MCP_INT_SLAVE_MASK) {
  		/* Mask the Slave interrupt and wake thread */
  		cdns_updatel(cdns, CDNS_MCP_INTMASK,

  			     CDNS_MCP_INT_SLAVE_MASK, 0);

  
  		int_status &= ~CDNS_MCP_INT_SLAVE_MASK;

  
  		/*
  		 * Deal with possible race condition between interrupt
  		 * handling and disabling interrupts on suspend.
  		 *
  		 * If the master is in the process of disabling
  		 * interrupts, don't schedule a workqueue
  		 */
  		if (cdns->interrupt_enabled)
  			schedule_work(&cdns->work);

  	}
  
  	cdns_writel(cdns, CDNS_MCP_INTSTAT, int_status);
  	return ret;
  }
  EXPORT_SYMBOL(sdw_cdns_irq);
  
  /**

   * To update slave status in a work since we will need to handle
   * other interrupts eg. CDNS_MCP_INT_RX_WL during the update slave
   * process.
   * @work: cdns worker thread

   */

  static void cdns_update_slave_status_work(struct work_struct *work)

  {

  	struct sdw_cdns *cdns =
  		container_of(work, struct sdw_cdns, work);

  	u32 slave0, slave1;

  	dev_dbg_ratelimited(cdns->dev, "Slave status change
  ");

  
  	slave0 = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT0);
  	slave1 = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT1);
  
  	cdns_update_slave_status(cdns, slave0, slave1);
  	cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT0, slave0);
  	cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT1, slave1);
  
  	/* clear and unmask Slave interrupt now */
  	cdns_writel(cdns, CDNS_MCP_INTSTAT, CDNS_MCP_INT_SLAVE_MASK);
  	cdns_updatel(cdns, CDNS_MCP_INTMASK,

  		     CDNS_MCP_INT_SLAVE_MASK, CDNS_MCP_INT_SLAVE_MASK);

  }

  
  /*
   * init routines
   */

  
  /**
   * sdw_cdns_exit_reset() - Program reset parameters and start bus operations
   * @cdns: Cadence instance
   */
  int sdw_cdns_exit_reset(struct sdw_cdns *cdns)
  {
  	/* program maximum length reset to be safe */
  	cdns_updatel(cdns, CDNS_MCP_CONTROL,
  		     CDNS_MCP_CONTROL_RST_DELAY,
  		     CDNS_MCP_CONTROL_RST_DELAY);
  
  	/* use hardware generated reset */
  	cdns_updatel(cdns, CDNS_MCP_CONTROL,
  		     CDNS_MCP_CONTROL_HW_RST,
  		     CDNS_MCP_CONTROL_HW_RST);

  	/* commit changes */

  	cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE,
  		     CDNS_MCP_CONFIG_UPDATE_BIT,
  		     CDNS_MCP_CONFIG_UPDATE_BIT);
  
  	/* don't wait here */
  	return 0;

  }
  EXPORT_SYMBOL(sdw_cdns_exit_reset);
  
  /**

   * sdw_cdns_enable_slave_interrupt() - Enable SDW slave interrupts
   * @cdns: Cadence instance
   * @state: boolean for true/false
   */
  static void cdns_enable_slave_interrupts(struct sdw_cdns *cdns, bool state)
  {
  	u32 mask;
  
  	mask = cdns_readl(cdns, CDNS_MCP_INTMASK);
  	if (state)
  		mask |= CDNS_MCP_INT_SLAVE_MASK;
  	else
  		mask &= ~CDNS_MCP_INT_SLAVE_MASK;
  
  	cdns_writel(cdns, CDNS_MCP_INTMASK, mask);
  }
  
  /**

   * sdw_cdns_enable_interrupt() - Enable SDW interrupts

   * @cdns: Cadence instance

   * @state: True if we are trying to enable interrupt.

   */

  int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns, bool state)

  {

  	u32 slave_intmask0 = 0;
  	u32 slave_intmask1 = 0;
  	u32 mask = 0;
  
  	if (!state)
  		goto update_masks;

  	slave_intmask0 = CDNS_MCP_SLAVE_INTMASK0_MASK;
  	slave_intmask1 = CDNS_MCP_SLAVE_INTMASK1_MASK;

  	/* enable detection of all slave state changes */
  	mask = CDNS_MCP_INT_SLAVE_MASK;
  
  	/* enable detection of bus issues */
  	mask |= CDNS_MCP_INT_CTRL_CLASH | CDNS_MCP_INT_DATA_CLASH |
  		CDNS_MCP_INT_PARITY;

  	/* port interrupt limited to test modes for now */
  	if (cdns->bus.params.m_data_mode != SDW_PORT_DATA_MODE_NORMAL)
  		mask |= CDNS_MCP_INT_DPINT;

  
  	/* enable detection of RX fifo level */
  	mask |= CDNS_MCP_INT_RX_WL;
  
  	/*
  	 * CDNS_MCP_INT_IRQ needs to be set otherwise all previous
  	 * settings are irrelevant
  	 */
  	mask |= CDNS_MCP_INT_IRQ;

  	if (interrupt_mask) /* parameter override */
  		mask = interrupt_mask;

  update_masks:

  	/* clear slave interrupt status before enabling interrupt */
  	if (state) {
  		u32 slave_state;
  
  		slave_state = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT0);
  		cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT0, slave_state);
  		slave_state = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT1);
  		cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT1, slave_state);
  	}

  	cdns->interrupt_enabled = state;
  
  	/*
  	 * Complete any on-going status updates before updating masks,
  	 * and cancel queued status updates.
  	 *
  	 * There could be a race with a new interrupt thrown before
  	 * the 3 mask updates below are complete, so in the interrupt
  	 * we use the 'interrupt_enabled' status to prevent new work
  	 * from being queued.
  	 */
  	if (!state)
  		cancel_work_sync(&cdns->work);

  	cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK0, slave_intmask0);
  	cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK1, slave_intmask1);

  	cdns_writel(cdns, CDNS_MCP_INTMASK, mask);

  	return 0;

  }
  EXPORT_SYMBOL(sdw_cdns_enable_interrupt);

  static int cdns_allocate_pdi(struct sdw_cdns *cdns,

  			     struct sdw_cdns_pdi **stream,
  			     u32 num, u32 pdi_offset)

  {
  	struct sdw_cdns_pdi *pdi;
  	int i;
  
  	if (!num)
  		return 0;
  
  	pdi = devm_kcalloc(cdns->dev, num, sizeof(*pdi), GFP_KERNEL);
  	if (!pdi)
  		return -ENOMEM;
  
  	for (i = 0; i < num; i++) {
  		pdi[i].num = i + pdi_offset;

  	}
  
  	*stream = pdi;
  	return 0;
  }
  
  /**
   * sdw_cdns_pdi_init() - PDI initialization routine
   *
   * @cdns: Cadence instance
   * @config: Stream configurations
   */
  int sdw_cdns_pdi_init(struct sdw_cdns *cdns,

  		      struct sdw_cdns_stream_config config)

  {
  	struct sdw_cdns_streams *stream;

  	int offset;
  	int ret;

  
  	cdns->pcm.num_bd = config.pcm_bd;
  	cdns->pcm.num_in = config.pcm_in;
  	cdns->pcm.num_out = config.pcm_out;
  	cdns->pdm.num_bd = config.pdm_bd;
  	cdns->pdm.num_in = config.pdm_in;
  	cdns->pdm.num_out = config.pdm_out;
  
  	/* Allocate PDIs for PCMs */
  	stream = &cdns->pcm;

  	/* we allocate PDI0 and PDI1 which are used for Bulk */
  	offset = 0;

  
  	ret = cdns_allocate_pdi(cdns, &stream->bd,
  				stream->num_bd, offset);
  	if (ret)
  		return ret;
  
  	offset += stream->num_bd;
  
  	ret = cdns_allocate_pdi(cdns, &stream->in,
  				stream->num_in, offset);
  	if (ret)
  		return ret;
  
  	offset += stream->num_in;
  
  	ret = cdns_allocate_pdi(cdns, &stream->out,
  				stream->num_out, offset);
  	if (ret)
  		return ret;
  
  	/* Update total number of PCM PDIs */
  	stream->num_pdi = stream->num_bd + stream->num_in + stream->num_out;
  	cdns->num_ports = stream->num_pdi;
  
  	/* Allocate PDIs for PDMs */
  	stream = &cdns->pdm;

  	ret = cdns_allocate_pdi(cdns, &stream->bd,
  				stream->num_bd, offset);
  	if (ret)
  		return ret;
  
  	offset += stream->num_bd;
  
  	ret = cdns_allocate_pdi(cdns, &stream->in,
  				stream->num_in, offset);
  	if (ret)
  		return ret;
  
  	offset += stream->num_in;
  
  	ret = cdns_allocate_pdi(cdns, &stream->out,
  				stream->num_out, offset);

  	if (ret)
  		return ret;
  
  	/* Update total number of PDM PDIs */
  	stream->num_pdi = stream->num_bd + stream->num_in + stream->num_out;
  	cdns->num_ports += stream->num_pdi;

  	return 0;
  }
  EXPORT_SYMBOL(sdw_cdns_pdi_init);

  static u32 cdns_set_initial_frame_shape(int n_rows, int n_cols)
  {
  	u32 val;
  	int c;
  	int r;
  
  	r = sdw_find_row_index(n_rows);

  	c = sdw_find_col_index(n_cols);

  	val = FIELD_PREP(CDNS_MCP_FRAME_SHAPE_ROW_MASK, r);
  	val |= FIELD_PREP(CDNS_MCP_FRAME_SHAPE_COL_MASK, c);

  
  	return val;
  }

  static void cdns_init_clock_ctrl(struct sdw_cdns *cdns)

  {

  	struct sdw_bus *bus = &cdns->bus;
  	struct sdw_master_prop *prop = &bus->prop;

  	u32 val;

  	u32 ssp_interval;

  	int divider;

  
  	/* Set clock divider */

  	divider	= (prop->mclk_freq / prop->max_clk_freq) - 1;

  	cdns_updatel(cdns, CDNS_MCP_CLK_CTRL0,
  		     CDNS_MCP_CLK_MCLKD_MASK, divider);
  	cdns_updatel(cdns, CDNS_MCP_CLK_CTRL1,
  		     CDNS_MCP_CLK_MCLKD_MASK, divider);

  	/*
  	 * Frame shape changes after initialization have to be done
  	 * with the bank switch mechanism
  	 */
  	val = cdns_set_initial_frame_shape(prop->default_row,
  					   prop->default_col);
  	cdns_writel(cdns, CDNS_MCP_FRAME_SHAPE_INIT, val);

  
  	/* Set SSP interval to default value */

  	ssp_interval = prop->default_frame_rate / SDW_CADENCE_GSYNC_HZ;
  	cdns_writel(cdns, CDNS_MCP_SSP_CTRL0, ssp_interval);
  	cdns_writel(cdns, CDNS_MCP_SSP_CTRL1, ssp_interval);

  }
  
  /**
   * sdw_cdns_init() - Cadence initialization
   * @cdns: Cadence instance
   */
  int sdw_cdns_init(struct sdw_cdns *cdns)
  {
  	u32 val;

  
  	cdns_init_clock_ctrl(cdns);

  	/* reset msg_count to default value of FIFOLEVEL */
  	cdns->msg_count = cdns_readl(cdns, CDNS_MCP_FIFOLEVEL);

  	/* flush command FIFOs */
  	cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_RST,
  		     CDNS_MCP_CONTROL_CMD_RST);

  	/* Set cmd accept mode */
  	cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_ACCEPT,

  		     CDNS_MCP_CONTROL_CMD_ACCEPT);

  
  	/* Configure mcp config */
  	val = cdns_readl(cdns, CDNS_MCP_CONFIG);

  	/* enable bus operations with clock and data */
  	val &= ~CDNS_MCP_CONFIG_OP;
  	val |= CDNS_MCP_CONFIG_OP_NORMAL;

  	/* Set cmd mode for Tx and Rx cmds */
  	val &= ~CDNS_MCP_CONFIG_CMD;

  	/* Disable sniffer mode */
  	val &= ~CDNS_MCP_CONFIG_SNIFFER;

  
  	/* Disable auto bus release */
  	val &= ~CDNS_MCP_CONFIG_BUS_REL;

  	if (cdns->bus.multi_link)
  		/* Set Multi-master mode to take gsync into account */
  		val |= CDNS_MCP_CONFIG_MMASTER;

  	/* leave frame delay to hardware default of 0x1F */

  	/* leave command retry to hardware default of 0 */

  	cdns_writel(cdns, CDNS_MCP_CONFIG, val);

  	/* changes will be committed later */
  	return 0;

  }
  EXPORT_SYMBOL(sdw_cdns_init);

  int cdns_bus_conf(struct sdw_bus *bus, struct sdw_bus_params *params)
  {

  	struct sdw_master_prop *prop = &bus->prop;

  	struct sdw_cdns *cdns = bus_to_cdns(bus);

  	int mcp_clkctrl_off;

  	int divider;
  
  	if (!params->curr_dr_freq) {

  		dev_err(cdns->dev, "NULL curr_dr_freq
  ");

  		return -EINVAL;
  	}

  	divider	= prop->mclk_freq * SDW_DOUBLE_RATE_FACTOR /
  		params->curr_dr_freq;
  	divider--; /* divider is 1/(N+1) */

  
  	if (params->next_bank)
  		mcp_clkctrl_off = CDNS_MCP_CLK_CTRL1;
  	else
  		mcp_clkctrl_off = CDNS_MCP_CLK_CTRL0;

  	cdns_updatel(cdns, mcp_clkctrl_off, CDNS_MCP_CLK_MCLKD_MASK, divider);

  
  	return 0;
  }
  EXPORT_SYMBOL(cdns_bus_conf);
  
  static int cdns_port_params(struct sdw_bus *bus,

  			    struct sdw_port_params *p_params, unsigned int bank)

  {
  	struct sdw_cdns *cdns = bus_to_cdns(bus);
  	int dpn_config = 0, dpn_config_off;
  
  	if (bank)
  		dpn_config_off = CDNS_DPN_B1_CONFIG(p_params->num);
  	else
  		dpn_config_off = CDNS_DPN_B0_CONFIG(p_params->num);
  
  	dpn_config = cdns_readl(cdns, dpn_config_off);

  	u32p_replace_bits(&dpn_config, (p_params->bps - 1), CDNS_DPN_CONFIG_WL);
  	u32p_replace_bits(&dpn_config, p_params->flow_mode, CDNS_DPN_CONFIG_PORT_FLOW);
  	u32p_replace_bits(&dpn_config, p_params->data_mode, CDNS_DPN_CONFIG_PORT_DAT);

  
  	cdns_writel(cdns, dpn_config_off, dpn_config);
  
  	return 0;
  }
  
  static int cdns_transport_params(struct sdw_bus *bus,

  				 struct sdw_transport_params *t_params,
  				 enum sdw_reg_bank bank)

  {
  	struct sdw_cdns *cdns = bus_to_cdns(bus);
  	int dpn_offsetctrl = 0, dpn_offsetctrl_off;
  	int dpn_config = 0, dpn_config_off;
  	int dpn_hctrl = 0, dpn_hctrl_off;
  	int num = t_params->port_num;
  	int dpn_samplectrl_off;
  
  	/*
  	 * Note: Only full data port is supported on the Master side for
  	 * both PCM and PDM ports.
  	 */
  
  	if (bank) {
  		dpn_config_off = CDNS_DPN_B1_CONFIG(num);
  		dpn_samplectrl_off = CDNS_DPN_B1_SAMPLE_CTRL(num);
  		dpn_hctrl_off = CDNS_DPN_B1_HCTRL(num);
  		dpn_offsetctrl_off = CDNS_DPN_B1_OFFSET_CTRL(num);
  	} else {
  		dpn_config_off = CDNS_DPN_B0_CONFIG(num);
  		dpn_samplectrl_off = CDNS_DPN_B0_SAMPLE_CTRL(num);
  		dpn_hctrl_off = CDNS_DPN_B0_HCTRL(num);
  		dpn_offsetctrl_off = CDNS_DPN_B0_OFFSET_CTRL(num);
  	}
  
  	dpn_config = cdns_readl(cdns, dpn_config_off);

  	u32p_replace_bits(&dpn_config, t_params->blk_grp_ctrl, CDNS_DPN_CONFIG_BGC);
  	u32p_replace_bits(&dpn_config, t_params->blk_pkg_mode, CDNS_DPN_CONFIG_BPM);

  	cdns_writel(cdns, dpn_config_off, dpn_config);

  	u32p_replace_bits(&dpn_offsetctrl, t_params->offset1, CDNS_DPN_OFFSET_CTRL_1);
  	u32p_replace_bits(&dpn_offsetctrl, t_params->offset2, CDNS_DPN_OFFSET_CTRL_2);

  	cdns_writel(cdns, dpn_offsetctrl_off,  dpn_offsetctrl);

  	u32p_replace_bits(&dpn_hctrl, t_params->hstart, CDNS_DPN_HCTRL_HSTART);
  	u32p_replace_bits(&dpn_hctrl, t_params->hstop, CDNS_DPN_HCTRL_HSTOP);
  	u32p_replace_bits(&dpn_hctrl, t_params->lane_ctrl, CDNS_DPN_HCTRL_LCTRL);

  
  	cdns_writel(cdns, dpn_hctrl_off, dpn_hctrl);
  	cdns_writel(cdns, dpn_samplectrl_off, (t_params->sample_interval - 1));
  
  	return 0;
  }
  
  static int cdns_port_enable(struct sdw_bus *bus,

  			    struct sdw_enable_ch *enable_ch, unsigned int bank)

  {
  	struct sdw_cdns *cdns = bus_to_cdns(bus);
  	int dpn_chnen_off, ch_mask;
  
  	if (bank)
  		dpn_chnen_off = CDNS_DPN_B1_CH_EN(enable_ch->port_num);
  	else
  		dpn_chnen_off = CDNS_DPN_B0_CH_EN(enable_ch->port_num);
  
  	ch_mask = enable_ch->ch_mask * enable_ch->enable;
  	cdns_writel(cdns, dpn_chnen_off, ch_mask);
  
  	return 0;
  }
  
  static const struct sdw_master_port_ops cdns_port_ops = {
  	.dpn_set_port_params = cdns_port_params,
  	.dpn_set_port_transport_params = cdns_transport_params,
  	.dpn_port_enable_ch = cdns_port_enable,
  };

  /**

   * sdw_cdns_is_clock_stop: Check clock status
   *
   * @cdns: Cadence instance
   */
  bool sdw_cdns_is_clock_stop(struct sdw_cdns *cdns)
  {
  	return !!(cdns_readl(cdns, CDNS_MCP_STAT) & CDNS_MCP_STAT_CLK_STOP);
  }
  EXPORT_SYMBOL(sdw_cdns_is_clock_stop);
  
  /**

   * sdw_cdns_clock_stop: Cadence clock stop configuration routine
   *
   * @cdns: Cadence instance
   * @block_wake: prevent wakes if required by the platform
   */
  int sdw_cdns_clock_stop(struct sdw_cdns *cdns, bool block_wake)
  {
  	bool slave_present = false;
  	struct sdw_slave *slave;
  	int ret;
  
  	/* Check suspend status */
  	if (sdw_cdns_is_clock_stop(cdns)) {
  		dev_dbg(cdns->dev, "Clock is already stopped
  ");
  		return 0;
  	}
  
  	/*

  	 * Before entering clock stop we mask the Slave
  	 * interrupts. This helps avoid having to deal with e.g. a
  	 * Slave becoming UNATTACHED while the clock is being stopped
  	 */
  	cdns_enable_slave_interrupts(cdns, false);
  
  	/*

  	 * For specific platforms, it is required to be able to put
  	 * master into a state in which it ignores wake-up trials
  	 * in clock stop state
  	 */
  	if (block_wake)
  		cdns_updatel(cdns, CDNS_MCP_CONTROL,
  			     CDNS_MCP_CONTROL_BLOCK_WAKEUP,
  			     CDNS_MCP_CONTROL_BLOCK_WAKEUP);
  
  	list_for_each_entry(slave, &cdns->bus.slaves, node) {
  		if (slave->status == SDW_SLAVE_ATTACHED ||
  		    slave->status == SDW_SLAVE_ALERT) {
  			slave_present = true;
  			break;
  		}
  	}
  
  	/*
  	 * This CMD_ACCEPT should be used when there are no devices
  	 * attached on the link when entering clock stop mode. If this is
  	 * not set and there is a broadcast write then the command ignored
  	 * will be treated as a failure
  	 */
  	if (!slave_present)
  		cdns_updatel(cdns, CDNS_MCP_CONTROL,
  			     CDNS_MCP_CONTROL_CMD_ACCEPT,
  			     CDNS_MCP_CONTROL_CMD_ACCEPT);
  	else
  		cdns_updatel(cdns, CDNS_MCP_CONTROL,
  			     CDNS_MCP_CONTROL_CMD_ACCEPT, 0);
  
  	/* commit changes */
  	ret = cdns_config_update(cdns);
  	if (ret < 0) {
  		dev_err(cdns->dev, "%s: config_update failed
  ", __func__);
  		return ret;
  	}
  
  	/* Prepare slaves for clock stop */
  	ret = sdw_bus_prep_clk_stop(&cdns->bus);
  	if (ret < 0) {
  		dev_err(cdns->dev, "prepare clock stop failed %d", ret);
  		return ret;
  	}
  
  	/*
  	 * Enter clock stop mode and only report errors if there are
  	 * Slave devices present (ALERT or ATTACHED)
  	 */
  	ret = sdw_bus_clk_stop(&cdns->bus);
  	if (ret < 0 && slave_present && ret != -ENODATA) {
  		dev_err(cdns->dev, "bus clock stop failed %d", ret);
  		return ret;
  	}
  
  	ret = cdns_set_wait(cdns, CDNS_MCP_STAT,
  			    CDNS_MCP_STAT_CLK_STOP,
  			    CDNS_MCP_STAT_CLK_STOP);
  	if (ret < 0)
  		dev_err(cdns->dev, "Clock stop failed %d
  ", ret);
  
  	return ret;
  }
  EXPORT_SYMBOL(sdw_cdns_clock_stop);
  
  /**
   * sdw_cdns_clock_restart: Cadence PM clock restart configuration routine
   *
   * @cdns: Cadence instance
   * @bus_reset: context may be lost while in low power modes and the bus
   * may require a Severe Reset and re-enumeration after a wake.
   */
  int sdw_cdns_clock_restart(struct sdw_cdns *cdns, bool bus_reset)
  {
  	int ret;

  	/* unmask Slave interrupts that were masked when stopping the clock */
  	cdns_enable_slave_interrupts(cdns, true);

  	ret = cdns_clear_bit(cdns, CDNS_MCP_CONTROL,
  			     CDNS_MCP_CONTROL_CLK_STOP_CLR);
  	if (ret < 0) {
  		dev_err(cdns->dev, "Couldn't exit from clock stop
  ");
  		return ret;
  	}
  
  	ret = cdns_set_wait(cdns, CDNS_MCP_STAT, CDNS_MCP_STAT_CLK_STOP, 0);
  	if (ret < 0) {
  		dev_err(cdns->dev, "clock stop exit failed %d
  ", ret);
  		return ret;
  	}
  
  	cdns_updatel(cdns, CDNS_MCP_CONTROL,
  		     CDNS_MCP_CONTROL_BLOCK_WAKEUP, 0);
  
  	/*
  	 * clear CMD_ACCEPT so that the command ignored
  	 * will be treated as a failure during a broadcast write
  	 */
  	cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_ACCEPT, 0);
  
  	if (!bus_reset) {
  
  		/* enable bus operations with clock and data */
  		cdns_updatel(cdns, CDNS_MCP_CONFIG,
  			     CDNS_MCP_CONFIG_OP,
  			     CDNS_MCP_CONFIG_OP_NORMAL);
  
  		ret = cdns_config_update(cdns);
  		if (ret < 0) {
  			dev_err(cdns->dev, "%s: config_update failed
  ", __func__);
  			return ret;
  		}
  
  		ret = sdw_bus_exit_clk_stop(&cdns->bus);
  		if (ret < 0)
  			dev_err(cdns->dev, "bus failed to exit clock stop %d
  ", ret);
  	}
  
  	return ret;
  }
  EXPORT_SYMBOL(sdw_cdns_clock_restart);
  
  /**

   * sdw_cdns_probe() - Cadence probe routine
   * @cdns: Cadence instance
   */
  int sdw_cdns_probe(struct sdw_cdns *cdns)
  {
  	init_completion(&cdns->tx_complete);

  	cdns->bus.port_ops = &cdns_port_ops;

  	INIT_WORK(&cdns->work, cdns_update_slave_status_work);

  	return 0;
  }
  EXPORT_SYMBOL(sdw_cdns_probe);

  int cdns_set_sdw_stream(struct snd_soc_dai *dai,

  			void *stream, bool pcm, int direction)

  {
  	struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
  	struct sdw_cdns_dma_data *dma;

  	if (stream) {
  		/* first paranoia check */
  		if (direction == SNDRV_PCM_STREAM_PLAYBACK)
  			dma = dai->playback_dma_data;
  		else
  			dma = dai->capture_dma_data;
  
  		if (dma) {
  			dev_err(dai->dev,
  				"dma_data already allocated for dai %s
  ",
  				dai->name);
  			return -EINVAL;
  		}

  		/* allocate and set dma info */
  		dma = kzalloc(sizeof(*dma), GFP_KERNEL);
  		if (!dma)
  			return -ENOMEM;

  		if (pcm)
  			dma->stream_type = SDW_STREAM_PCM;
  		else
  			dma->stream_type = SDW_STREAM_PDM;

  		dma->bus = &cdns->bus;
  		dma->link_id = cdns->instance;

  		dma->stream = stream;

  		if (direction == SNDRV_PCM_STREAM_PLAYBACK)
  			dai->playback_dma_data = dma;
  		else
  			dai->capture_dma_data = dma;
  	} else {
  		/* for NULL stream we release allocated dma_data */
  		if (direction == SNDRV_PCM_STREAM_PLAYBACK) {
  			kfree(dai->playback_dma_data);
  			dai->playback_dma_data = NULL;
  		} else {
  			kfree(dai->capture_dma_data);
  			dai->capture_dma_data = NULL;
  		}
  	}

  	return 0;
  }
  EXPORT_SYMBOL(cdns_set_sdw_stream);
  
  /**
   * cdns_find_pdi() - Find a free PDI
   *
   * @cdns: Cadence instance

   * @offset: Starting offset

   * @num: Number of PDIs
   * @pdi: PDI instances

   * @dai_id: DAI id

   *

   * Find a PDI for a given PDI array. The PDI num and dai_id are
   * expected to match, return NULL otherwise.

   */
  static struct sdw_cdns_pdi *cdns_find_pdi(struct sdw_cdns *cdns,

  					  unsigned int offset,

  					  unsigned int num,

  					  struct sdw_cdns_pdi *pdi,
  					  int dai_id)

  {
  	int i;

  	for (i = offset; i < offset + num; i++)
  		if (pdi[i].num == dai_id)
  			return &pdi[i];

  
  	return NULL;
  }
  
  /**
   * sdw_cdns_config_stream: Configure a stream
   *
   * @cdns: Cadence instance

   * @ch: Channel count
   * @dir: Data direction
   * @pdi: PDI to be used
   */
  void sdw_cdns_config_stream(struct sdw_cdns *cdns,

  			    u32 ch, u32 dir, struct sdw_cdns_pdi *pdi)

  {
  	u32 offset, val = 0;

  	if (dir == SDW_DATA_DIR_RX) {

  		val = CDNS_PORTCTRL_DIRN;

  		if (cdns->bus.params.m_data_mode != SDW_PORT_DATA_MODE_NORMAL)
  			val |= CDNS_PORTCTRL_TEST_FAILED;
  	}

  	offset = CDNS_PORTCTRL + pdi->num * CDNS_PORT_OFFSET;

  	cdns_updatel(cdns, offset,
  		     CDNS_PORTCTRL_DIRN | CDNS_PORTCTRL_TEST_FAILED,
  		     val);

  	val = pdi->num;

  	val |= CDNS_PDI_CONFIG_SOFT_RESET;

  	val |= FIELD_PREP(CDNS_PDI_CONFIG_CHANNEL, (1 << ch) - 1);

  	cdns_writel(cdns, CDNS_PDI_CONFIG(pdi->num), val);
  }
  EXPORT_SYMBOL(sdw_cdns_config_stream);
  
  /**

   * sdw_cdns_alloc_pdi() - Allocate a PDI

   *
   * @cdns: Cadence instance
   * @stream: Stream to be allocated

   * @ch: Channel count
   * @dir: Data direction

   * @dai_id: DAI id

   */

  struct sdw_cdns_pdi *sdw_cdns_alloc_pdi(struct sdw_cdns *cdns,
  					struct sdw_cdns_streams *stream,

  					u32 ch, u32 dir, int dai_id)

  {
  	struct sdw_cdns_pdi *pdi = NULL;
  
  	if (dir == SDW_DATA_DIR_RX)

  		pdi = cdns_find_pdi(cdns, 0, stream->num_in, stream->in,
  				    dai_id);

  	else

  		pdi = cdns_find_pdi(cdns, 0, stream->num_out, stream->out,
  				    dai_id);

  
  	/* check if we found a PDI, else find in bi-directional */
  	if (!pdi)

  		pdi = cdns_find_pdi(cdns, 2, stream->num_bd, stream->bd,
  				    dai_id);

  	if (pdi) {
  		pdi->l_ch_num = 0;
  		pdi->h_ch_num = ch - 1;
  		pdi->dir = dir;
  		pdi->ch_count = ch;
  	}

  	return pdi;

  }

  EXPORT_SYMBOL(sdw_cdns_alloc_pdi);

  MODULE_LICENSE("Dual BSD/GPL");
  MODULE_DESCRIPTION("Cadence Soundwire Library");