drivers/soundwire/cadence_master.c

// 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/soundwire/sdw_registers.h>
#include <linux/soundwire/sdw.h>
#include <sound/pcm_params.h>
#include <sound/soc.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_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_OFFSET		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_H			GENMASK(23, 16)
#define CDNS_MCP_CMD_REG_ADDR_L			GENMASK(15, 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_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\n");
		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\n");

	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\n", 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\n");
	ret += scnprintf(buf + ret, RD_BUF - ret, "\nMCP Registers\n");
	/* 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,
			 "\nStatus & Intr Registers\n");
	/* 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,
			 "\nSSP & Clk ctrl Registers\n");
	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,
			 "\nDPn B0 Registers\n");

	num_ports = cdns->num_ports;

	for (i = 0; i < num_ports; i++) {
		ret += scnprintf(buf + ret, RD_BUF - ret,
				 "\nDP-%d\n", 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,
			 "\nDPn B1 Registers\n");
	for (i = 0; i < num_ports; i++) {
		ret += scnprintf(buf + ret, RD_BUF - ret,
				 "\nDP-%d\n", 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,
			 "\nDPn Control Registers\n");
	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,
			 "\nPDIn Config Registers\n");

	/* 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\n", ret);

	return ret;
}

DEFINE_DEBUGFS_ATTRIBUTE(cdns_hw_reset_fops, NULL, cdns_hw_reset, "%llu\n");

/**
 * 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);
}
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\n");
			if (cdns->response_buf[i] & CDNS_MCP_RESP_NACK) {
				nack = 1;
				dev_err_ratelimited(cdns->dev, "Msg NACK received\n");
			}
		}
	}

	if (nack) {
		dev_err_ratelimited(cdns->dev, "Msg NACKed for Slave %d\n", msg->dev_num);
		return SDW_CMD_FAIL;
	}

	if (no_ack) {
		dev_dbg_ratelimited(cdns->dev, "Msg ignored for Slave %d\n", msg->dev_num);
		return SDW_CMD_IGNORED;
	}

	/* fill response */
	for (i = 0; i < count; i++)
		msg->buf[i + offset] = cdns->response_buf[i] >>
				SDW_REG_SHIFT(CDNS_MCP_RESP_RDATA);

	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 = msg->dev_num << SDW_REG_SHIFT(CDNS_MCP_CMD_DEV_ADDR);
		data |= cmd << SDW_REG_SHIFT(CDNS_MCP_CMD_COMMAND);
		data |= addr++  << SDW_REG_SHIFT(CDNS_MCP_CMD_REG_ADDR_L);

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

		data |= msg->ssp_sync << SDW_REG_SHIFT(CDNS_MCP_CMD_SSP_TAG);
		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\n",
			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] = msg->dev_num << SDW_REG_SHIFT(CDNS_MCP_CMD_DEV_ADDR);
	data[0] |= 0x3 << SDW_REG_SHIFT(CDNS_MCP_CMD_COMMAND);
	data[1] = data[0];

	data[0] |= SDW_SCP_ADDRPAGE1 << SDW_REG_SHIFT(CDNS_MCP_CMD_REG_ADDR_L);
	data[1] |= SDW_SCP_ADDRPAGE2 << SDW_REG_SHIFT(CDNS_MCP_CMD_REG_ADDR_L);

	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\n");
		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\n");
			if (cdns->response_buf[i] & CDNS_MCP_RESP_NACK) {
				nack = 1;
				dev_err(cdns->dev, "Program SCP NACK received\n");
			}
		}
	}

	/* 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\n", msg->dev_num);
		return SDW_CMD_FAIL;
	}

	if (no_ack) {
		dev_dbg_ratelimited(cdns->dev,
				    "SCP_addrpage ignored for Slave %d\n", 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\n", 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\n",
					     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\n",
					     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\n");
	}

	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\n");
	}

	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\n");
	}

	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;
		ret = IRQ_WAKE_THREAD;
	}

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

/**
 * sdw_cdns_thread() - Cadence irq thread handler
 * @irq: irq number
 * @dev_id: irq context
 */
irqreturn_t sdw_cdns_thread(int irq, void *dev_id)
{
	struct sdw_cdns *cdns = dev_id;
	u32 slave0, slave1;

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

	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);

	return IRQ_HANDLED;
}
EXPORT_SYMBOL(sdw_cdns_thread);

/*
 * 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;

	/* no detection of port interrupts for now */

	/* 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_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) & CDNS_MCP_FRAME_SHAPE_COL_MASK;

	val = (r << CDNS_MCP_FRAME_SHAPE_ROW_OFFSET) | 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\n");
		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);

	dpn_config |= ((p_params->bps - 1) <<
				SDW_REG_SHIFT(CDNS_DPN_CONFIG_WL));
	dpn_config |= (p_params->flow_mode <<
				SDW_REG_SHIFT(CDNS_DPN_CONFIG_PORT_FLOW));
	dpn_config |= (p_params->data_mode <<
				SDW_REG_SHIFT(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);

	dpn_config |= (t_params->blk_grp_ctrl <<
				SDW_REG_SHIFT(CDNS_DPN_CONFIG_BGC));
	dpn_config |= (t_params->blk_pkg_mode <<
				SDW_REG_SHIFT(CDNS_DPN_CONFIG_BPM));
	cdns_writel(cdns, dpn_config_off, dpn_config);

	dpn_offsetctrl |= (t_params->offset1 <<
				SDW_REG_SHIFT(CDNS_DPN_OFFSET_CTRL_1));
	dpn_offsetctrl |= (t_params->offset2 <<
				SDW_REG_SHIFT(CDNS_DPN_OFFSET_CTRL_2));
	cdns_writel(cdns, dpn_offsetctrl_off,  dpn_offsetctrl);

	dpn_hctrl |= (t_params->hstart <<
				SDW_REG_SHIFT(CDNS_DPN_HCTRL_HSTART));
	dpn_hctrl |= (t_params->hstop << SDW_REG_SHIFT(CDNS_DPN_HCTRL_HSTOP));
	dpn_hctrl |= (t_params->lane_ctrl <<
				SDW_REG_SHIFT(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\n");
		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\n", __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\n", 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\n");
		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\n", 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\n", __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\n", 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;

	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;

	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;

	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;

	offset = CDNS_PORTCTRL + pdi->num * CDNS_PORT_OFFSET;
	cdns_updatel(cdns, offset, CDNS_PORTCTRL_DIRN, val);

	val = pdi->num;
	val |= CDNS_PDI_CONFIG_SOFT_RESET;
	val |= ((1 << ch) - 1) << SDW_REG_SHIFT(CDNS_PDI_CONFIG_CHANNEL);
	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");