[PATCH v2 1/1] drivers: i2c: add brcm iproc I2C driver support

Rayagonda Kokatanur rayagonda.kokatanur at broadcom.com
Thu Mar 26 11:51:27 CET 2020


Add I2C driver support for Broadcom iproc-based socs.

Signed-off-by: Arjun Jyothi <arjun.jyothi at broadcom.com>
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur at broadcom.com>
Signed-off-by: Sheetal Tigadoli <sheetal.tigadoli at broadcom.com>
Signed-off-by: Vladimir Olovyannikov <vladimir.olovyannikov at broadcom.com>
---
Changes from v1:
 -Address all review comments from Heiko Schocher

 drivers/i2c/Kconfig     |   8 +
 drivers/i2c/Makefile    |   1 +
 drivers/i2c/iproc_i2c.c | 713 ++++++++++++++++++++++++++++++++++++++++
 drivers/i2c/iproc_i2c.h | 344 +++++++++++++++++++
 4 files changed, 1066 insertions(+)
 create mode 100644 drivers/i2c/iproc_i2c.c
 create mode 100644 drivers/i2c/iproc_i2c.h

diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index 03d2fed341..71c827927a 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -71,6 +71,14 @@ config SYS_I2C_AT91
 	  i2c-gpio driver unless your system can cope with this limitation.
 	  Binding info: doc/device-tree-bindings/i2c/i2c-at91.txt
 
+config IPROC_I2C
+	bool "Broadcom I2C driver"
+	depends on DM_I2C
+	help
+	  Broadcom I2C driver.
+	  Add support for Broadcom I2C driver.
+	  Say yes here to to enable the Broadco I2C driver.
+
 config SYS_I2C_FSL
        bool "Freescale I2C bus driver"
        depends on DM_I2C
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index f5a471f887..1ab7a941ca 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_SYS_I2C_FSL) += fsl_i2c.o
 obj-$(CONFIG_SYS_I2C_IHS) += ihs_i2c.o
 obj-$(CONFIG_SYS_I2C_INTEL) += intel_i2c.o
 obj-$(CONFIG_SYS_I2C_IMX_LPI2C) += imx_lpi2c.o
+obj-$(CONFIG_IPROC_I2C) += iproc_i2c.o
 obj-$(CONFIG_SYS_I2C_KONA) += kona_i2c.o
 obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
 obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
diff --git a/drivers/i2c/iproc_i2c.c b/drivers/i2c/iproc_i2c.c
new file mode 100644
index 0000000000..ea28c18da5
--- /dev/null
+++ b/drivers/i2c/iproc_i2c.c
@@ -0,0 +1,713 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Broadcom
+ *
+ */
+
+#include <asm/io.h>
+#include <common.h>
+#include <config.h>
+#include <dm.h>
+#include "errno.h"
+#include <i2c.h>
+#include "iproc_i2c.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct iproc_i2c_regs {
+	u32 cfg_reg;
+	u32 timg_cfg;
+	u32 addr_reg;
+	u32 mstr_fifo_ctrl;
+	u32 slv_fifo_ctrl;
+	u32 bitbng_ctrl;
+	u32 blnks[6]; /* Not to be used */
+	u32 mstr_cmd;
+	u32 slv_cmd;
+	u32 evt_en;
+	u32 evt_sts;
+	u32 mstr_datawr;
+	u32 mstr_datard;
+	u32 slv_datawr;
+	u32 slv_datard;
+};
+
+struct iproc_i2c {
+	struct iproc_i2c_regs __iomem *base; /* register base */
+	int bus_speed;
+	int i2c_init_done;
+};
+
+/* Function to read a value from specified register. */
+static unsigned int iproc_i2c_reg_read(u32 *reg_addr)
+{
+	unsigned int val;
+
+	val = readl((void *)(reg_addr));
+	return cpu_to_le32(val);
+}
+
+/* Function to write a value ('val') in to a specified register. */
+static int iproc_i2c_reg_write(u32 *reg_addr, unsigned int val)
+{
+	val = cpu_to_le32(val);
+	writel(val, (void *)(reg_addr));
+	return  0;
+}
+
+#if defined(DEBUG)
+static int iproc_dump_i2c_regs(struct iproc_i2c *bus_prvdata)
+{
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	unsigned int regval;
+
+	debug("\n----------------------------------------------\n");
+	debug("%s: Dumping SMBus registers...\n", __func__);
+
+	regval = iproc_i2c_reg_read(&base->cfg_reg);
+	debug("CCB_SMB_CFG_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->timg_cfg);
+	debug("CCB_SMB_TIMGCFG_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->addr_reg);
+	debug("CCB_SMB_ADDR_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->mstr_fifo_ctrl);
+	debug("CCB_SMB_MSTRFIFOCTL_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->slv_fifo_ctrl);
+	debug("CCB_SMB_SLVFIFOCTL_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->bitbng_ctrl);
+	debug("CCB_SMB_BITBANGCTL_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->mstr_cmd);
+	debug("CCB_SMB_MSTRCMD_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->slv_cmd);
+	debug("CCB_SMB_SLVCMD_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->evt_en);
+	debug("CCB_SMB_EVTEN_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->evt_sts);
+	debug("CCB_SMB_EVTSTS_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->mstr_datawr);
+	debug("CCB_SMB_MSTRDATAWR_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->mstr_datard);
+	debug("CCB_SMB_MSTRDATARD_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->slv_datawr);
+	debug("CCB_SMB_SLVDATAWR_REG=0x%08X\n", regval);
+
+	regval = iproc_i2c_reg_read(&base->slv_datard);
+	debug("CCB_SMB_SLVDATARD_REG=0x%08X\n", regval);
+
+	debug("----------------------------------------------\n\n");
+	return 0;
+}
+#else
+static int iproc_dump_i2c_regs(struct iproc_i2c *bus_prvdata)
+{
+	return 0;
+}
+#endif
+
+/*
+ * Function to ensure that the previous transaction was completed before
+ * initiating a new transaction. It can also be used in polling mode to
+ * check status of completion of a command
+ */
+static int iproc_i2c_startbusy_wait(struct iproc_i2c *bus_prvdata)
+{
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	unsigned int regval;
+
+	regval = iproc_i2c_reg_read(&base->mstr_cmd);
+
+	/* Check if an operation is in progress. During probe it won't be.
+	 * But when shutdown/remove was called we want to make sure that
+	 * the transaction in progress completed
+	 */
+	if (regval & CCB_SMB_MSTRSTARTBUSYCMD_MASK) {
+		unsigned int i = 0;
+
+		do {
+			mdelay(10);
+			i++;
+			regval = iproc_i2c_reg_read(&base->mstr_cmd);
+
+			/* If start-busy bit cleared, exit the loop */
+		} while ((regval & CCB_SMB_MSTRSTARTBUSYCMD_MASK) &&
+			 (i < IPROC_SMB_MAX_RETRIES));
+
+		if (i >= IPROC_SMB_MAX_RETRIES) {
+			pr_err("%s: START_BUSY bit didn't clear, exiting\n",
+			       __func__);
+			return -ETIMEDOUT;
+		}
+	}
+	return 0;
+}
+
+/*
+ * This function set clock frequency for SMBus block. As per hardware
+ * engineering, the clock frequency can be changed dynamically.
+ */
+static int iproc_i2c_set_clk_freq(struct iproc_i2c *bus_prvdata)
+{
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	unsigned int regval;
+
+	regval = iproc_i2c_reg_read(&base->timg_cfg);
+
+	switch (bus_prvdata->bus_speed) {
+	case I2C_SPEED_100KHZ:
+		regval &= ~CCB_SMB_TIMGCFG_MODE400_MASK;
+		break;
+
+	case I2C_SPEED_400KHZ:
+		regval |= CCB_SMB_TIMGCFG_MODE400_MASK;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	iproc_i2c_reg_write(&base->timg_cfg, regval);
+	return 0;
+}
+
+static int iproc_i2c_init(struct udevice *bus)
+{
+	struct iproc_i2c *bus_prvdata = dev_get_priv(bus);
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	unsigned int regval;
+
+	debug("\nEntering %s\n", __func__);
+
+	/* Put controller in reset */
+	regval = iproc_i2c_reg_read(&base->cfg_reg);
+	regval |= CCB_SMB_CFG_RST_MASK;
+	regval &= ~CCB_SMB_CFG_SMBEN_MASK;
+	iproc_i2c_reg_write(&base->cfg_reg, regval);
+
+	/* Wait 100 usec as per spec */
+	udelay(100);
+
+	/* bring controller out of reset */
+	regval &= ~CCB_SMB_CFG_RST_MASK;
+	iproc_i2c_reg_write(&base->cfg_reg, regval);
+
+	/* Flush Tx, Rx FIFOs. Note we are setting the Rx FIFO threshold to 0.
+	 * May be OK since we are setting RX_EVENT and RX_FIFO_FULL interrupts
+	 */
+	regval = CCB_SMB_MSTRRXFIFOFLSH_MASK | CCB_SMB_MSTRTXFIFOFLSH_MASK;
+	iproc_i2c_reg_write(&base->mstr_fifo_ctrl, regval);
+
+	/* Enable SMbus block. Note, we are setting MASTER_RETRY_COUNT to zero
+	 * since there will be only one master
+	 */
+	regval = iproc_i2c_reg_read(&base->cfg_reg);
+	regval |= CCB_SMB_CFG_SMBEN_MASK;
+	iproc_i2c_reg_write(&base->cfg_reg, regval);
+
+	/* Set default clock frequency */
+	iproc_i2c_set_clk_freq(bus_prvdata);
+
+	/* Disable intrs */
+	iproc_i2c_reg_write(&base->evt_en, 0);
+
+	/* Clear intrs (W1TC) */
+	regval = iproc_i2c_reg_read(&base->evt_sts);
+	iproc_i2c_reg_write(&base->evt_sts, regval);
+
+	bus_prvdata->i2c_init_done = 1;
+
+	iproc_dump_i2c_regs(bus_prvdata);
+	debug("%s: Init successful\n", __func__);
+
+	return 0;
+}
+
+/*
+ * This function copies data to SMBus's Tx FIFO. Valid for write transactions
+ * only
+ *
+ * base_addr: Mapped address of this SMBus instance
+ * dev_addr:  SMBus (I2C) device address. We are assuming 7-bit addresses
+ *            initially
+ * info:   Data to copy in to Tx FIFO. For read commands, the size should be
+ *         set to zero by the caller
+ *
+ */
+static void iproc_i2c_write_trans_data(struct iproc_i2c *bus_prvdata,
+				       unsigned short dev_addr,
+				       struct iproc_xact_info *info)
+{
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	unsigned int regval;
+	unsigned int i;
+	unsigned int num_data_bytes = 0;
+
+	debug("%s: dev_addr=0x%X cmd_valid=%d cmd=0x%02x size=%u proto=%d buf[] %x\n",
+	      __func__, dev_addr, info->cmd_valid,
+	      info->command, info->size, info->smb_proto, info->data[0]);
+
+	/* Write SMBus device address first */
+	/* Note, we are assuming 7-bit addresses for now. For 10-bit addresses,
+	 * we may have one more write to send the upper 3 bits of 10-bit addr
+	 */
+	iproc_i2c_reg_write(&base->mstr_datawr, dev_addr);
+
+	/* If the protocol needs command code, copy it */
+	if (info->cmd_valid)
+		iproc_i2c_reg_write(&base->mstr_datawr, info->command);
+
+	/* Depending on the SMBus protocol, we need to write additional
+	 * transaction data in to Tx FIFO. Refer to section 5.5 of SMBus
+	 * spec for sequence for a transaction
+	 */
+	switch (info->smb_proto) {
+	case SMBUS_PROT_RECV_BYTE:
+		/* No additional data to be written */
+		num_data_bytes = 0;
+		break;
+
+	case SMBUS_PROT_SEND_BYTE:
+		num_data_bytes = info->size;
+		break;
+
+	case SMBUS_PROT_RD_BYTE:
+	case SMBUS_PROT_RD_WORD:
+	case SMBUS_PROT_BLK_RD:
+		/* Write slave address with R/W~ set (bit #0) */
+		iproc_i2c_reg_write(&base->mstr_datawr,
+				    dev_addr | 0x1);
+		num_data_bytes = 0;
+		break;
+
+	case SMBUS_PROT_BLK_WR_BLK_RD_PROC_CALL:
+		iproc_i2c_reg_write(&base->mstr_datawr,
+				    dev_addr | 0x1 |
+				    CCB_SMB_MSTRWRSTS_MASK);
+		num_data_bytes = 0;
+		break;
+
+	case SMBUS_PROT_WR_BYTE:
+	case SMBUS_PROT_WR_WORD:
+		/* No additional bytes to be written.
+		 * Data portion is written in the
+		 * 'for' loop below
+		 */
+		num_data_bytes = info->size;
+		break;
+
+	case SMBUS_PROT_BLK_WR:
+		/* 3rd byte is byte count */
+		iproc_i2c_reg_write(&base->mstr_datawr, info->size);
+		num_data_bytes = info->size;
+		break;
+
+	default:
+		return;
+	}
+
+	/* Copy actual data from caller, next. In general, for reads,
+	 * no data is copied
+	 */
+	for (i = 0; num_data_bytes; --num_data_bytes, i++) {
+		/* For the last byte, set MASTER_WR_STATUS bit */
+		regval = (num_data_bytes == 1) ?
+			 info->data[i] | CCB_SMB_MSTRWRSTS_MASK :
+			 info->data[i];
+
+		iproc_i2c_reg_write(&base->mstr_datawr, regval);
+	}
+}
+
+static int iproc_i2c_data_send(struct iproc_i2c *bus_prvdata,
+			       unsigned short addr,
+			       struct iproc_xact_info *info)
+{
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	int rc, retry = 3;
+	unsigned int regval;
+
+	/* Make sure the previous transaction completed */
+	rc = iproc_i2c_startbusy_wait(bus_prvdata);
+
+	if (rc < 0) {
+		pr_err("%s: Send: bus is busy, exiting\n", __func__);
+		return rc;
+	}
+
+	/* Write transaction bytes to Tx FIFO */
+	iproc_i2c_write_trans_data(bus_prvdata, addr, info);
+
+	/* Program master command register (0x30) with protocol type and set
+	 * start_busy_command bit to initiate the write transaction
+	 */
+	regval = (info->smb_proto << CCB_SMB_MSTRSMBUSPROTO_SHIFT) |
+		 CCB_SMB_MSTRSTARTBUSYCMD_MASK;
+
+	iproc_i2c_reg_write(&base->mstr_cmd, regval);
+
+	/* Check for Master status */
+	regval = iproc_i2c_reg_read(&base->mstr_cmd);
+	while (regval & CCB_SMB_MSTRSTARTBUSYCMD_MASK) {
+		mdelay(10);
+		if (retry-- <= 0)
+			break;
+		regval = iproc_i2c_reg_read(&base->mstr_cmd);
+	}
+
+	/* If start_busy bit cleared, check if there are any errors */
+	if (!(regval & CCB_SMB_MSTRSTARTBUSYCMD_MASK)) {
+		/* start_busy bit cleared, check master_status field now */
+		regval &= CCB_SMB_MSTRSTS_MASK;
+		regval >>= CCB_SMB_MSTRSTS_SHIFT;
+
+		if (regval != MSTR_STS_XACT_SUCCESS) {
+			/* Error We can flush Tx FIFO here */
+			pr_err("%s: ERROR: Error in transaction %u, exiting\n",
+			       __func__, regval);
+			return -EREMOTEIO;
+		}
+	}
+
+	return 0;
+}
+
+static int iproc_i2c_data_recv(struct iproc_i2c *bus_prvdata,
+			       unsigned short addr,
+			       struct iproc_xact_info *info,
+			       unsigned int *num_bytes_read)
+{
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	int rc, retry = 3;
+	unsigned int regval;
+
+	/* Make sure the previous transaction completed */
+	rc = iproc_i2c_startbusy_wait(bus_prvdata);
+
+	if (rc < 0) {
+		pr_err("%s: Receive: Bus is busy, exiting\n", __func__);
+		return rc;
+	}
+
+	/* Program all transaction bytes into master Tx FIFO */
+	iproc_i2c_write_trans_data(bus_prvdata, addr, info);
+
+	/* Program master command register (0x30) with protocol type and set
+	 * start_busy_command bit to initiate the write transaction
+	 */
+	regval = (info->smb_proto << CCB_SMB_MSTRSMBUSPROTO_SHIFT) |
+		 CCB_SMB_MSTRSTARTBUSYCMD_MASK | info->size;
+
+	iproc_i2c_reg_write(&base->mstr_cmd, regval);
+
+	/* Check for Master status */
+	regval = iproc_i2c_reg_read(&base->mstr_cmd);
+	while (regval & CCB_SMB_MSTRSTARTBUSYCMD_MASK) {
+		udelay(1000);
+		if (retry-- <= 0)
+			break;
+		regval = iproc_i2c_reg_read(&base->mstr_cmd);
+	}
+
+	/* If start_busy bit cleared, check if there are any errors */
+	if (!(regval & CCB_SMB_MSTRSTARTBUSYCMD_MASK)) {
+		/* start_busy bit cleared, check master_status field now */
+		regval &= CCB_SMB_MSTRSTS_MASK;
+		regval >>= CCB_SMB_MSTRSTS_SHIFT;
+
+		if (regval != MSTR_STS_XACT_SUCCESS) {
+			/* We can flush Tx FIFO here */
+			pr_err("%s: Error in transaction %d, exiting\n",
+			       __func__, regval);
+			return -EREMOTEIO;
+		}
+	}
+
+	/* Read received byte(s), after TX out address etc */
+	regval = iproc_i2c_reg_read(&base->mstr_datard);
+
+	/* For block read, protocol (hw) returns byte count,
+	 * as the first byte
+	 */
+	if (info->smb_proto == SMBUS_PROT_BLK_RD) {
+		int i;
+
+		*num_bytes_read = regval & CCB_SMB_MSTRRDDATA_MASK;
+
+		/* Limit to reading a max of 32 bytes only; just a safeguard.
+		 * If # bytes read is a number > 32, check transaction set up,
+		 * and contact hw engg. Assumption: PEC is disabled
+		 */
+		for (i = 0;
+		     (i < *num_bytes_read) && (i < I2C_SMBUS_BLOCK_MAX);
+		     i++) {
+			/* Read Rx FIFO for data bytes */
+			regval = iproc_i2c_reg_read(&base->mstr_datard);
+			info->data[i] = regval & CCB_SMB_MSTRRDDATA_MASK;
+		}
+	} else {
+		/* 1 Byte data */
+		*info->data = regval & CCB_SMB_MSTRRDDATA_MASK;
+		*num_bytes_read = 1;
+	}
+
+	return 0;
+}
+
+static int i2c_write_byte(struct iproc_i2c *bus_prvdata,
+			  u8 devaddr, u8 regoffset, u8 value)
+{
+	int rc;
+	struct iproc_xact_info info;
+
+	devaddr <<= 1;
+
+	info.cmd_valid = 1;
+	info.command = (unsigned char)regoffset;
+	info.data = &value;
+	info.size = 1;
+	info.flags = 0;
+	info.smb_proto = SMBUS_PROT_WR_BYTE;
+	/* Refer to i2c_smbus_write_byte params passed. */
+	rc = iproc_i2c_data_send(bus_prvdata, devaddr, &info);
+
+	if (rc < 0) {
+		pr_err("%s: %s error accessing device 0x%X\n",
+		       __func__, "Write", devaddr);
+		return -EREMOTEIO;
+	}
+
+	return 0;
+}
+
+int i2c_write(struct udevice *bus,
+	      uchar chip, uint regaddr, int alen, uchar *buffer, int len)
+{
+	struct iproc_i2c *bus_prvdata = dev_get_priv(bus);
+	int i, data_len;
+	u8 *data;
+
+	if (len > 256) {
+		pr_err("I2C write: address out of range\n");
+		return 1;
+	}
+
+	if (len < 1) {
+		pr_err("I2C write: Need offset addr and value\n");
+		return 1;
+	}
+
+	/* buffer contains offset addr followed by value to be written */
+	regaddr = buffer[0];
+	data = &buffer[1];
+	data_len = len - 1;
+
+	for (i = 0; i < data_len; i++) {
+		if (i2c_write_byte(bus_prvdata, chip, regaddr + i, data[i])) {
+			pr_err("I2C write (%d): I/O error\n", i);
+			iproc_i2c_init(bus);
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+static int i2c_read_byte(struct iproc_i2c *bus_prvdata,
+			 u8 devaddr, u8 regoffset, u8 *value)
+{
+	int rc;
+	struct iproc_xact_info info;
+	unsigned int num_bytes_read = 0;
+
+	devaddr <<= 1;
+
+	info.cmd_valid = 1;
+	info.command = (unsigned char)regoffset;
+	info.data = value;
+	info.size = 1;
+	info.flags = 0;
+	info.smb_proto = SMBUS_PROT_RD_BYTE;
+	/* Refer to i2c_smbus_read_byte for params passed. */
+	rc = iproc_i2c_data_recv(bus_prvdata, devaddr, &info, &num_bytes_read);
+
+	if (rc < 0) {
+		pr_err("%s: %s error accessing device 0x%X\n",
+		       __func__, "Read", devaddr);
+		return -EREMOTEIO;
+	}
+
+	return 0;
+}
+
+int i2c_read(struct udevice *bus,
+	     uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+	struct iproc_i2c *bus_prvdata = dev_get_priv(bus);
+	int i;
+
+	if (len > 256) {
+		pr_err("I2C read: address out of range\n");
+		return 1;
+	}
+
+	for (i = 0; i < len; i++) {
+		if (i2c_read_byte(bus_prvdata, chip, addr + i, &buffer[i])) {
+			pr_err("I2C read: I/O error\n");
+			iproc_i2c_init(bus);
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+static int iproc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
+{
+	int ret = 0;
+
+	debug("%s: %d messages\n", __func__, nmsgs);
+
+	for (; nmsgs > 0; nmsgs--, msg++) {
+		if (msg->flags & I2C_M_RD)
+			ret = i2c_read(bus, msg->addr, 0, 0,
+				       msg->buf, msg->len);
+		else
+			ret = i2c_write(bus, msg->addr, 0, 0,
+					msg->buf, msg->len);
+	}
+
+	return ret;
+}
+
+static int iproc_i2c_probe_chip(struct udevice *bus, uint chip_addr,
+				uint chip_flags)
+{
+	struct iproc_i2c *bus_prvdata = dev_get_priv(bus);
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	u32 regval;
+
+	debug("\n%s: Entering chip probe\n", __func__);
+
+	/* Init internal regs, disable intrs (and then clear intrs), set fifo
+	 * thresholds, etc.
+	 */
+	if (!bus_prvdata->i2c_init_done)
+		iproc_i2c_init(bus);
+
+	regval = (chip_addr << 1);
+	iproc_i2c_reg_write(&base->mstr_datawr, regval);
+	regval = ((SMBUS_PROT_QUICK_CMD << CCB_SMB_MSTRSMBUSPROTO_SHIFT) |
+			(1 << CCB_SMB_MSTRSTARTBUSYCMD_SHIFT));
+	iproc_i2c_reg_write(&base->mstr_cmd, regval);
+
+	do {
+		udelay(100);
+		regval = iproc_i2c_reg_read(&base->mstr_cmd);
+		regval &= CCB_SMB_MSTRSTARTBUSYCMD_MASK;
+	}  while (regval);
+
+	regval = iproc_i2c_reg_read(&base->mstr_cmd);
+
+	if ((regval & CCB_SMB_MSTRSTS_MASK) != 0)
+		return -1;
+
+	iproc_dump_i2c_regs(bus_prvdata);
+	debug("%s: chip probe successful\n", __func__);
+
+	return 0;
+}
+
+static int iproc_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
+{
+	struct iproc_i2c *bus_prvdata = dev_get_priv(bus);
+
+	bus_prvdata->bus_speed = speed;
+	return iproc_i2c_set_clk_freq(bus_prvdata);
+}
+
+/**
+ * i2c_get_bus_speed - get i2c bus speed
+ *
+ * This function returns the speed of operation in Hz
+ */
+int iproc_i2c_get_bus_speed(struct udevice *bus)
+{
+	struct iproc_i2c *bus_prvdata = dev_get_priv(bus);
+	struct iproc_i2c_regs *base = bus_prvdata->base;
+	unsigned int regval;
+	int ret = 0;
+
+	regval = iproc_i2c_reg_read(&base->timg_cfg);
+	regval = (regval & CCB_SMB_TIMGCFG_MODE400_MASK) >>
+		  CCB_SMB_TIMGCFG_MODE400_SHIFT;
+
+	switch (regval) {
+	case 0:
+		ret = I2C_SPEED_100KHZ;
+		break;
+	case 1:
+		ret = I2C_SPEED_400KHZ;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static int iproc_i2c_probe(struct udevice *bus)
+{
+	return iproc_i2c_init(bus);
+}
+
+static int iproc_i2c_ofdata_to_platdata(struct udevice *bus)
+{
+	struct iproc_i2c *bus_prvdata = dev_get_priv(bus);
+	int node = dev_of_offset(bus);
+	const void *blob = gd->fdt_blob;
+
+	bus_prvdata->base = map_physmem(devfdt_get_addr(bus),
+					sizeof(void *),
+					MAP_NOCACHE);
+
+	bus_prvdata->bus_speed =
+		fdtdec_get_int(blob, node, "bus-frequency",
+			       I2C_SPEED_100KHZ); /* default 100KHz freq */
+
+	return 0;
+}
+
+static const struct dm_i2c_ops iproc_i2c_ops = {
+	.xfer		= iproc_i2c_xfer,
+	.probe_chip	= iproc_i2c_probe_chip,
+	.set_bus_speed	= iproc_i2c_set_bus_speed,
+	.get_bus_speed	= iproc_i2c_get_bus_speed,
+};
+
+static const struct udevice_id iproc_i2c_ids[] = {
+	{ .compatible = "brcm,iproc-i2c" },
+	{ }
+};
+
+U_BOOT_DRIVER(iproc_i2c) = {
+	.name	= "iproc_i2c",
+	.id	= UCLASS_I2C,
+	.of_match = iproc_i2c_ids,
+	.ofdata_to_platdata = iproc_i2c_ofdata_to_platdata,
+	.probe	= iproc_i2c_probe,
+	.priv_auto_alloc_size = sizeof(struct iproc_i2c),
+	.ops	= &iproc_i2c_ops,
+	.flags  = DM_FLAG_PRE_RELOC,
+};
diff --git a/drivers/i2c/iproc_i2c.h b/drivers/i2c/iproc_i2c.h
new file mode 100644
index 0000000000..3ca405fcda
--- /dev/null
+++ b/drivers/i2c/iproc_i2c.h
@@ -0,0 +1,344 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018 Broadcom
+ *
+ */
+
+#ifndef __IPROC_I2C_H__
+#define __IPROC_I2C_H__
+
+/* Registers */
+#define CCB_SMB_CFG_REG 0x0
+
+#define CCB_SMB_CFG_RST_MASK                         0x80000000
+#define CCB_SMB_CFG_RST_SHIFT                        31
+
+#define CCB_SMB_CFG_SMBEN_MASK                       0x40000000
+#define CCB_SMB_CFG_SMBEN_SHIFT                      30
+
+#define CCB_SMB_CFG_BITBANGEN_MASK                   0x20000000
+#define CCB_SMB_CFG_BITBANGEN_SHIFT                  29
+
+#define CCB_SMB_CFG_EN_NIC_SMBADDR0_MASK             0x10000000
+#define CCB_SMB_CFG_EN_NIC_SMBADDR0_SHIFT            28
+
+#define CCB_SMB_CFG_PROMISCMODE_MASK                 0x08000000
+#define CCB_SMB_CFG_PROMISCMODE_SHIFT                27
+
+#define CCB_SMB_CFG_TSTMPCNTEN_MASK                  0x04000000
+#define CCB_SMB_CFG_TSTMPCNTEN_SHIFT                 26
+
+#define CCB_SMB_CFG_MSTRRTRYCNT_MASK                 0x000F0000
+#define CCB_SMB_CFG_MSTRRTRYCNT_SHIFT                16
+
+#define CCB_SMB_TIMGCFG_REG 0x4
+
+#define CCB_SMB_TIMGCFG_MODE400_MASK                 0x80000000
+#define CCB_SMB_TIMGCFG_MODE400_SHIFT                31
+
+#define CCB_SMB_TIMGCFG_RNDSLVSTR_MASK               0x7F000000
+#define CCB_SMB_TIMGCFG_RNDSLVSTR_SHIFT              24
+
+#define CCB_SMB_TIMGCFG_PERSLVSTR_MASK               0x00FF0000
+#define CCB_SMB_TIMGCFG_PERSLVSTR_SHIFT              16
+
+#define CCB_SMB_TIMGCFG_IDLTIME_MASK                 0x0000FF00
+#define CCB_SMB_TIMGCFG_IDLTIME_SHIFT                8
+
+#define CCB_SMB_ADDR_REG 0x8
+
+#define CCB_SMB_EN_NIC_SMBADDR3_MASK                 0x80000000
+#define CCB_SMB_EN_NIC_SMBADDR3_SHIFT                31
+
+#define CCB_SMB_NIC_SMBADDR3_MASK                    0x7F000000
+#define CCB_SMB_NIC_SMBADDR3_SHIFT                   24
+
+#define CCB_SMB_EN_NIC_SMBADDR2_MASK                 0x00800000
+#define CCB_SMB_EN_NIC_SMBADDR2_SHIFT                23
+
+#define CCB_SMB_NIC_SMBADDR2_MASK                    0x007F0000
+#define CCB_SMB_NIC_SMBADDR2_SHIFT                   16
+
+#define CCB_SMB_EN_NIC_SMBADDR1_MASK                 0x00008000
+#define CCB_SMB_EN_NIC_SMBADDR1_SHIFT                15
+
+#define CCB_SMB_NIC_SMBADDR1_MASK                    0x00007F00
+#define CCB_SMB_NIC_SMBADDR1_SHIFT                   8
+
+#define CCB_SMB_EN_NIC_SMBADDR0_MASK                 0x00000080
+#define CCB_SMB_EN_NIC_SMBADDR0_SHIFT                7
+
+#define CCB_SMB_NIC_SMBADDR0_MASK                    0x0000007F
+#define CCB_SMB_NIC_SMBADDR0_SHIFT                   0
+
+#define CCB_SMB_MSTRFIFOCTL_REG 0xC
+
+#define CCB_SMB_MSTRRXFIFOFLSH_MASK                  0x80000000
+#define CCB_SMB_MSTRRXFIFOFLSH_SHIFT                 31
+
+#define CCB_SMB_MSTRTXFIFOFLSH_MASK                  0x40000000
+#define CCB_SMB_MSTRTXFIFOFLSH_SHIFT                 30
+
+#define CCB_SMB_MSTRRXPKTCNT_MASK                    0x007F0000
+#define CCB_SMB_MSTRRXPKTCNT_SHIFT                   16
+
+#define CCB_SMB_MSTRRXFIFOTHR_MASK                   0x00003F00
+#define CCB_SMB_MSTRRXFIFOTHR_SHIFT                  8
+
+#define CCB_SMB_SLVFIFOCTL_REG 0x10
+
+#define CCB_SMB_SLVRXFIFOFLSH_MASK                   0x80000000
+#define CCB_SMB_SLVRXFIFOFLSH_SHIFT                  31
+
+#define CCB_SMB_SLVTXFIFOFLSH_MASK                   0x40000000
+#define CCB_SMB_SLVTXFIFOFLSH_SHIFT                  30
+
+#define CCB_SMB_SLVRXPKTCNT_MASK                     0x007F0000
+#define CCB_SMB_SLVRXPKTCNT_SHIFT                    16
+
+#define CCB_SMB_SLVRXFIFOTHR_MASK                    0x00003F00
+#define CCB_SMB_SLVRXFIFOTHR_SHIFT                   8
+
+#define CCB_SMB_BITBANGCTL_REG 0x14
+
+#define CCB_SMB_SMBCLKIN_MASK                        0x80000000
+#define CCB_SMB_SMBCLKIN_SHIFT                       31
+
+#define CCB_SMB_SMBCLKOUTEN_MASK                     0x40000000
+#define CCB_SMB_SMBCLKOUTEN_SHIFT                    30
+
+#define CCB_SMB_SMBDATAIN_MASK                       0x20000000
+#define CCB_SMB_SMBDATAIN_SHIFT                      29
+
+#define CCB_SMB_SMBDATAOUTEN_MASK                    0x10000000
+#define CCB_SMB_SMBDATAOUTEN_SHIFT                   28
+
+#define CCB_SMB_MSTRCMD_REG 0x30
+
+#define CCB_SMB_MSTRSTARTBUSYCMD_MASK                0x80000000
+#define CCB_SMB_MSTRSTARTBUSYCMD_SHIFT               31
+
+#define CCB_SMB_MSTRABORT_MASK                       0x40000000
+#define CCB_SMB_MSTRABORT_SHIFT                      30
+
+#define CCB_SMB_MSTRSTS_MASK                         0x0E000000
+#define CCB_SMB_MSTRSTS_SHIFT                        25
+
+#define CCB_SMB_MSTRSMBUSPROTO_MASK                  0x00001E00
+#define CCB_SMB_MSTRSMBUSPROTO_SHIFT                 9
+
+#define CCB_SMB_MSTRPEC_MASK                         0x00000100
+#define CCB_SMB_MSTRPEC_SHIFT                        8
+
+#define CCB_SMB_MSTRRDBYTECNT_MASK                   0x000000FF
+#define CCB_SMB_MSTRRDBYTECNT_SHIFT                  0
+
+#define CCB_SMB_SLVCMD_REG 0x34
+
+#define CCB_SMB_SLVSTARTBUSYCMD_MASK                 0x80000000
+#define CCB_SMB_SLVSTARTBUSYCMD_SHIFT                31
+
+#define CCB_SMB_SLVABORT_MASK                        0x40000000
+#define CCB_SMB_SLVABORT_SHIFT                       30
+
+#define CCB_SMB_SLVSTS_MASK                          0x03800000
+#define CCB_SMB_SLVSTS_SHIFT                         23
+
+#define CCB_SMB_SLVPEC_MASK                          0x00000100
+#define CCB_SMB_SLVPEC_SHIFT                         8
+
+#define CCB_SMB_EVTEN_REG 0x38
+
+#define CCB_SMB_MSTRRXFIFOFULLEN_MASK                0x80000000
+#define CCB_SMB_MSTRRXFIFOFULLEN_SHIFT               31
+
+#define CCB_SMB_MSTRRXFIFOTHRHITEN_MASK              0x40000000
+#define CCB_SMB_MSTRRXFIFOTHRHITEN_SHIFT             30
+
+#define CCB_SMB_MSTRRXEVTEN_MASK                     0x20000000
+#define CCB_SMB_MSTRRXEVTEN_SHIFT                    29
+
+#define CCB_SMB_MSTRSTARTBUSYEN_MASK                 0x10000000
+#define CCB_SMB_MSTRSTARTBUSYEN_SHIFT                28
+
+#define CCB_SMB_MSTRTXUNDEN_MASK                     0x08000000
+#define CCB_SMB_MSTRTXUNDEN_SHIFT                    27
+
+#define CCB_SMB_SLVRXFIFOFULLEN_MASK                 0x04000000
+#define CCB_SMB_SLVRXFIFOFULLEN_SHIFT                26
+
+#define CCB_SMB_SLVRXFIFOTHRHITEN_MASK               0x02000000
+#define CCB_SMB_SLVRXFIFOTHRHITEN_SHIFT              25
+
+#define CCB_SMB_SLVRXEVTEN_MASK                      0x01000000
+#define CCB_SMB_SLVRXEVTEN_SHIFT                     24
+
+#define CCB_SMB_SLVSTARTBUSYEN_MASK                  0x00800000
+#define CCB_SMB_SLVSTARTBUSYEN_SHIFT                 23
+
+#define CCB_SMB_SLVTXUNDEN_MASK                      0x00400000
+#define CCB_SMB_SLVTXUNDEN_SHIFT                     22
+
+#define CCB_SMB_SLVRDEVTEN_MASK                      0x00200000
+#define CCB_SMB_SLVRDEVTEN_SHIFT                     21
+
+#define CCB_SMB_EVTSTS_REG 0x3C
+
+#define CCB_SMB_MSTRRXFIFOFULLSTS_MASK               0x80000000
+#define CCB_SMB_MSTRRXFIFOFULLSTS_SHIFT              31
+
+#define CCB_SMB_MSTRRXFIFOTHRHITSTS_MASK             0x40000000
+#define CCB_SMB_MSTRRXFIFOTHRHITSTS_SHIFT            30
+
+#define CCB_SMB_MSTRRXEVTSTS_MASK                    0x20000000
+#define CCB_SMB_MSTRRXEVTSTS_SHIFT                   29
+
+#define CCB_SMB_MSTRSTARTBUSYSTS_MASK                0x10000000
+#define CCB_SMB_MSTRSTARTBUSYSTS_SHIFT               28
+
+#define CCB_SMB_MSTRTXUNDSTS_MASK                    0x08000000
+#define CCB_SMB_MSTRTXUNDSTS_SHIFT                   27
+
+#define CCB_SMB_SLVRXFIFOFULLSTS_MASK                0x04000000
+#define CCB_SMB_SLVRXFIFOFULLSTS_SHIFT               26
+
+#define CCB_SMB_SLVRXFIFOTHRHITSTS_MASK              0x02000000
+#define CCB_SMB_SLVRXFIFOTHRHITSTS_SHIFT             25
+
+#define CCB_SMB_SLVRXEVTSTS_MASK                     0x01000000
+#define CCB_SMB_SLVRXEVTSTS_SHIFT                    24
+
+#define CCB_SMB_SLVSTARTBUSYSTS_MASK                 0x00800000
+#define CCB_SMB_SLVSTARTBUSYSTS_SHIFT                23
+
+#define CCB_SMB_SLVTXUNDSTS_MASK                     0x00400000
+#define CCB_SMB_SLVTXUNDSTS_SHIFT                    22
+
+#define CCB_SMB_SLVRDEVTSTS_MASK                     0x00200000
+#define CCB_SMB_SLVRDEVTSTS_SHIFT                    21
+
+#define CCB_SMB_MSTRDATAWR_REG 0x40
+
+#define CCB_SMB_MSTRWRSTS_MASK                       0x80000000
+#define CCB_SMB_MSTRWRSTS_SHIFT                      31
+
+#define CCB_SMB_MSTRWRDATA_MASK                      0x000000FF
+#define CCB_SMB_MSTRWRDATA_SHIFT                     0
+
+#define CCB_SMB_MSTRDATARD_REG 0x44
+
+#define CCB_SMB_MSTRRDSTS_MASK                       0xC0000000
+#define CCB_SMB_MSTRRDSTS_SHIFT                      30
+
+#define CCB_SMB_MSTRRDPECERR_MASK                    0x20000000
+#define CCB_SMB_MSTRRDPECERR_SHIFT                   29
+
+#define CCB_SMB_MSTRRDDATA_MASK                      0x000000FF
+#define CCB_SMB_MSTRRDDATA_SHIFT                     0
+
+#define CCB_SMB_SLVDATAWR_REG 0x48
+
+#define CCB_SMB_SLVWRSTS_MASK                        0x80000000
+#define CCB_SMB_SLVWRSTS_SHIFT                       31
+
+#define CCB_SMB_SLVWRDATA_MASK                       0x000000FF
+#define CCB_SMB_SLVWRDATA_SHIFT                      0
+
+#define CCB_SMB_SLVDATARD_REG 0x4C
+
+#define CCB_SMB_SLVRDSTS_MASK                        0xC0000000
+#define CCB_SMB_SLVRDSTS_SHIFT                       30
+
+#define CCB_SMB_SLVRDERRSTS_MASK                     0x30000000
+#define CCB_SMB_SLVRDERRSTS_SHIFT                    28
+
+#define CCB_SMB_SLVRDDATA_MASK                       0x000000FF
+#define CCB_SMB_SLVRDDATA_SHIFT                      0
+
+/* --Registers-- */
+
+/* Transaction error codes defined in Master command register (0x30) */
+#define MSTR_STS_XACT_SUCCESS          0
+#define MSTR_STS_LOST_ARB              1
+#define MSTR_STS_NACK_FIRST_BYTE       2
+
+/* NACK on a byte other than
+ * the first byte
+ */
+#define MSTR_STS_NACK_NON_FIRST_BYTE   3
+
+#define MSTR_STS_TTIMEOUT_EXCEEDED     4
+#define MSTR_STS_TX_TLOW_MEXT_EXCEEDED 5
+#define MSTR_STS_RX_TLOW_MEXT_EXCEEDED 6
+
+/* SMBUS protocol values defined in register 0x30 */
+#define SMBUS_PROT_QUICK_CMD               0
+#define SMBUS_PROT_SEND_BYTE               1
+#define SMBUS_PROT_RECV_BYTE               2
+#define SMBUS_PROT_WR_BYTE                 3
+#define SMBUS_PROT_RD_BYTE                 4
+#define SMBUS_PROT_WR_WORD                 5
+#define SMBUS_PROT_RD_WORD                 6
+#define SMBUS_PROT_BLK_WR                  7
+#define SMBUS_PROT_BLK_RD                  8
+#define SMBUS_PROT_PROC_CALL               9
+#define SMBUS_PROT_BLK_WR_BLK_RD_PROC_CALL 10
+
+/* SMBUS Block speed mode */
+#define SMBUS_BLOCK_MODE_100		0
+#define SMBUS_BLOCK_MODE_400		1
+
+#define BUS_BUSY_COUNT         100000 /* Number can be changed later */
+#define IPROC_I2C_INVALID_ADDR 0xFF
+#define IPROC_SMB_MAX_RETRIES   35
+#define I2C_SMBUS_BLOCK_MAX     32
+#define GETREGFLDVAL(regval, mask, startbit) \
+		    (((regval) & (mask)) >> (startbit))
+
+/* Enum to specify clock speed. The user will provide it during initialization
+ * If needed, it can be changed dynamically
+ */
+enum iproc_smb_clk_freq {
+	I2C_SPEED_100KHZ = 100000,
+	I2C_SPEED_400KHZ = 400000,
+	I2C_SPEED_INVALID = 255
+};
+
+/* This enum will be used to notify the user of status of a data transfer
+ * request
+ */
+enum iproc_smb_error_code {
+	I2C_NO_ERR = 0,
+	I2C_TIMEOUT_ERR = 1,
+
+	/* Invalid parameter(s) passed to the driver */
+	I2C_INVALID_PARAM_ERR = 2,
+
+	/* The driver API was called before the present
+	 * transfer was completed
+	 */
+	I2C_OPER_IN_PROGRESS = 3,
+
+	/* Transfer aborted unexpectedly, for example a NACK
+	 * received, before last byte was read/written
+	 */
+	I2C_OPER_ABORT_ERR = 4,
+
+	/* Feature or function not supported
+	 * (e.g., 10-bit addresses, or clock speeds
+	 * other than 100KHz, 400KHz)
+	 */
+	I2C_FUNC_NOT_SUPPORTED = 5,
+};
+
+/* Structure used to pass information to read/write functions. */
+struct iproc_xact_info {
+	unsigned char command;
+	unsigned char *data;
+	unsigned int size;
+	unsigned short flags; /* used for specifying PEC, 10-bit addresses */
+	unsigned char smb_proto; /* SMBus protocol */
+	unsigned int cmd_valid; /* true if command is valid else false */
+};
+
+#endif /* __IPROC_I2C_H__ */
-- 
2.17.1



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