i2c: designware: Convert driver to multibus/multiadapter framework

In preparation for the SoCFPGA support of the designware I2C driver,
convert this driver to the common CONFIG_SYS_I2C framework.

This patch converts all users of this driver, this is:

- ST spearxxx boards
- AXS101 (ARC700 platform)

I couldn't test this patch on those boards. Only compile tested for all
spear boards. And tested on SoCFPGA.

Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Alexey Brodkin <abrodkin@synopsys.com>
Tested-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Heiko Schocher <hs@denx.de>
Cc: Vipin Kumar <vk.vipin@gmail.com>
Cc: Jeroen Hofstee <jeroen@myspectrum.nl>

2 files changed, 128 insertions, 167 deletions

diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 3191680..d067897 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -6,7 +6,6 @@
 #
 
 obj-$(CONFIG_BFIN_TWI_I2C) += bfin-twi_i2c.o
-obj-$(CONFIG_DW_I2C) += designware_i2c.o
 obj-$(CONFIG_I2C_MV) += mv_i2c.o
 obj-$(CONFIG_PCA9564_I2C) += pca9564_i2c.o
 obj-$(CONFIG_TSI108_I2C) += tsi108_i2c.o
@@ -14,6 +13,7 @@ obj-$(CONFIG_U8500_I2C) += u8500_i2c.o
 obj-$(CONFIG_SH_SH7734_I2C) += sh_sh7734_i2c.o
 obj-$(CONFIG_SYS_I2C) += i2c_core.o
 obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o
+obj-$(CONFIG_SYS_I2C_DW) += designware_i2c.o
 obj-$(CONFIG_SYS_I2C_FSL) += fsl_i2c.o
 obj-$(CONFIG_SYS_I2C_FTI2C010) += fti2c010.o
 obj-$(CONFIG_SYS_I2C_IHS) += ihs_i2c.o
diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c
index e085a70..e768cde 100644
--- a/drivers/i2c/designware_i2c.c
+++ b/drivers/i2c/designware_i2c.c
@@ -6,17 +6,33 @@
  */
 
 #include <common.h>
+#include <i2c.h>
 #include <asm/io.h>
 #include "designware_i2c.h"
-#include <i2c.h>
 
-#ifdef CONFIG_I2C_MULTI_BUS
-static unsigned int bus_initialized[CONFIG_SYS_I2C_BUS_MAX];
-static unsigned int current_bus = 0;
+static struct i2c_regs *i2c_get_base(struct i2c_adapter *adap)
+{
+	switch (adap->hwadapnr) {
+#if CONFIG_SYS_I2C_BUS_MAX >= 4
+	case 3:
+		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE3;
+#endif
+#if CONFIG_SYS_I2C_BUS_MAX >= 3
+	case 2:
+		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE2;
+#endif
+#if CONFIG_SYS_I2C_BUS_MAX >= 2
+	case 1:
+		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE1;
 #endif
+	case 0:
+		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE;
+	default:
+		printf("Wrong I2C-adapter number %d\n", adap->hwadapnr);
+	}
 
-static struct i2c_regs *i2c_regs_p =
-    (struct i2c_regs *)CONFIG_SYS_I2C_BASE;
+	return NULL;
+}
 
 /*
  * set_speed - Set the i2c speed mode (standard, high, fast)
@@ -24,51 +40,52 @@ static struct i2c_regs *i2c_regs_p =
  *
  * Set the i2c speed mode (standard, high, fast)
  */
-static void set_speed(int i2c_spd)
+static void set_speed(struct i2c_adapter *adap, int i2c_spd)
 {
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
 	unsigned int cntl;
 	unsigned int hcnt, lcnt;
 	unsigned int enbl;
 
 	/* to set speed cltr must be disabled */
-	enbl = readl(&i2c_regs_p->ic_enable);
+	enbl = readl(&i2c_base->ic_enable);
 	enbl &= ~IC_ENABLE_0B;
-	writel(enbl, &i2c_regs_p->ic_enable);
+	writel(enbl, &i2c_base->ic_enable);
 
-	cntl = (readl(&i2c_regs_p->ic_con) & (~IC_CON_SPD_MSK));
+	cntl = (readl(&i2c_base->ic_con) & (~IC_CON_SPD_MSK));
 
 	switch (i2c_spd) {
 	case IC_SPEED_MODE_MAX:
 		cntl |= IC_CON_SPD_HS;
 		hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO;
-		writel(hcnt, &i2c_regs_p->ic_hs_scl_hcnt);
+		writel(hcnt, &i2c_base->ic_hs_scl_hcnt);
 		lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO;
-		writel(lcnt, &i2c_regs_p->ic_hs_scl_lcnt);
+		writel(lcnt, &i2c_base->ic_hs_scl_lcnt);
 		break;
 
 	case IC_SPEED_MODE_STANDARD:
 		cntl |= IC_CON_SPD_SS;
 		hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO;
-		writel(hcnt, &i2c_regs_p->ic_ss_scl_hcnt);
+		writel(hcnt, &i2c_base->ic_ss_scl_hcnt);
 		lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO;
-		writel(lcnt, &i2c_regs_p->ic_ss_scl_lcnt);
+		writel(lcnt, &i2c_base->ic_ss_scl_lcnt);
 		break;
 
 	case IC_SPEED_MODE_FAST:
 	default:
 		cntl |= IC_CON_SPD_FS;
 		hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO;
-		writel(hcnt, &i2c_regs_p->ic_fs_scl_hcnt);
+		writel(hcnt, &i2c_base->ic_fs_scl_hcnt);
 		lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO;
-		writel(lcnt, &i2c_regs_p->ic_fs_scl_lcnt);
+		writel(lcnt, &i2c_base->ic_fs_scl_lcnt);
 		break;
 	}
 
-	writel(cntl, &i2c_regs_p->ic_con);
+	writel(cntl, &i2c_base->ic_con);
 
 	/* Enable back i2c now speed set */
 	enbl |= IC_ENABLE_0B;
-	writel(enbl, &i2c_regs_p->ic_enable);
+	writel(enbl, &i2c_base->ic_enable);
 }
 
 /*
@@ -77,7 +94,8 @@ static void set_speed(int i2c_spd)
  *
  * Set the i2c speed.
  */
-int i2c_set_bus_speed(unsigned int speed)
+static unsigned int dw_i2c_set_bus_speed(struct i2c_adapter *adap,
+					 unsigned int speed)
 {
 	int i2c_spd;
 
@@ -88,28 +106,8 @@ int i2c_set_bus_speed(unsigned int speed)
 	else
 		i2c_spd = IC_SPEED_MODE_STANDARD;
 
-	set_speed(i2c_spd);
-
-	return i2c_spd;
-}
-
-/*
- * i2c_get_bus_speed - Gets the i2c speed
- *
- * Gets the i2c speed.
- */
-unsigned int i2c_get_bus_speed(void)
-{
-	u32 cntl;
-
-	cntl = (readl(&i2c_regs_p->ic_con) & IC_CON_SPD_MSK);
-
-	if (cntl == IC_CON_SPD_HS)
-		return I2C_MAX_SPEED;
-	else if (cntl == IC_CON_SPD_FS)
-		return I2C_FAST_SPEED;
-	else if (cntl == IC_CON_SPD_SS)
-		return I2C_STANDARD_SPEED;
+	set_speed(adap, i2c_spd);
+	adap->speed = speed;
 
 	return 0;
 }
@@ -117,34 +115,32 @@ unsigned int i2c_get_bus_speed(void)
 /*
  * i2c_init - Init function
  * @speed:	required i2c speed
- * @slaveadd:	slave address for the device
+ * @slaveaddr:	slave address for the device
  *
  * Initialization function.
  */
-void i2c_init(int speed, int slaveadd)
+static void dw_i2c_init(struct i2c_adapter *adap, int speed,
+			int slaveaddr)
 {
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
 	unsigned int enbl;
 
 	/* Disable i2c */
-	enbl = readl(&i2c_regs_p->ic_enable);
+	enbl = readl(&i2c_base->ic_enable);
 	enbl &= ~IC_ENABLE_0B;
-	writel(enbl, &i2c_regs_p->ic_enable);
+	writel(enbl, &i2c_base->ic_enable);
 
-	writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_regs_p->ic_con);
-	writel(IC_RX_TL, &i2c_regs_p->ic_rx_tl);
-	writel(IC_TX_TL, &i2c_regs_p->ic_tx_tl);
-	i2c_set_bus_speed(speed);
-	writel(IC_STOP_DET, &i2c_regs_p->ic_intr_mask);
-	writel(slaveadd, &i2c_regs_p->ic_sar);
+	writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_base->ic_con);
+	writel(IC_RX_TL, &i2c_base->ic_rx_tl);
+	writel(IC_TX_TL, &i2c_base->ic_tx_tl);
+	dw_i2c_set_bus_speed(adap, speed);
+	writel(IC_STOP_DET, &i2c_base->ic_intr_mask);
+	writel(slaveaddr, &i2c_base->ic_sar);
 
 	/* Enable i2c */
-	enbl = readl(&i2c_regs_p->ic_enable);
+	enbl = readl(&i2c_base->ic_enable);
 	enbl |= IC_ENABLE_0B;
-	writel(enbl, &i2c_regs_p->ic_enable);
-
-#ifdef CONFIG_I2C_MULTI_BUS
-	bus_initialized[current_bus] = 1;
-#endif
+	writel(enbl, &i2c_base->ic_enable);
 }
 
 /*
@@ -153,21 +149,22 @@ void i2c_init(int speed, int slaveadd)
  *
  * Sets the target slave address.
  */
-static void i2c_setaddress(unsigned int i2c_addr)
+static void i2c_setaddress(struct i2c_adapter *adap, unsigned int i2c_addr)
 {
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
 	unsigned int enbl;
 
 	/* Disable i2c */
-	enbl = readl(&i2c_regs_p->ic_enable);
+	enbl = readl(&i2c_base->ic_enable);
 	enbl &= ~IC_ENABLE_0B;
-	writel(enbl, &i2c_regs_p->ic_enable);
+	writel(enbl, &i2c_base->ic_enable);
 
-	writel(i2c_addr, &i2c_regs_p->ic_tar);
+	writel(i2c_addr, &i2c_base->ic_tar);
 
 	/* Enable i2c */
-	enbl = readl(&i2c_regs_p->ic_enable);
+	enbl = readl(&i2c_base->ic_enable);
 	enbl |= IC_ENABLE_0B;
-	writel(enbl, &i2c_regs_p->ic_enable);
+	writel(enbl, &i2c_base->ic_enable);
 }
 
 /*
@@ -175,10 +172,12 @@ static void i2c_setaddress(unsigned int i2c_addr)
  *
  * Flushes the i2c RX FIFO
  */
-static void i2c_flush_rxfifo(void)
+static void i2c_flush_rxfifo(struct i2c_adapter *adap)
 {
-	while (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE)
-		readl(&i2c_regs_p->ic_cmd_data);
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
+
+	while (readl(&i2c_base->ic_status) & IC_STATUS_RFNE)
+		readl(&i2c_base->ic_cmd_data);
 }
 
 /*
@@ -186,12 +185,13 @@ static void i2c_flush_rxfifo(void)
  *
  * Waits for bus busy
  */
-static int i2c_wait_for_bb(void)
+static int i2c_wait_for_bb(struct i2c_adapter *adap)
 {
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
 	unsigned long start_time_bb = get_timer(0);
 
-	while ((readl(&i2c_regs_p->ic_status) & IC_STATUS_MA) ||
-	       !(readl(&i2c_regs_p->ic_status) & IC_STATUS_TFE)) {
+	while ((readl(&i2c_base->ic_status) & IC_STATUS_MA) ||
+	       !(readl(&i2c_base->ic_status) & IC_STATUS_TFE)) {
 
 		/* Evaluate timeout */
 		if (get_timer(start_time_bb) > (unsigned long)(I2C_BYTE_TO_BB))
@@ -201,40 +201,44 @@ static int i2c_wait_for_bb(void)
 	return 0;
 }
 
-static int i2c_xfer_init(uchar chip, uint addr, int alen)
+static int i2c_xfer_init(struct i2c_adapter *adap, uchar chip, uint addr,
+			 int alen)
 {
-	if (i2c_wait_for_bb())
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
+
+	if (i2c_wait_for_bb(adap))
 		return 1;
 
-	i2c_setaddress(chip);
+	i2c_setaddress(adap, chip);
 	while (alen) {
 		alen--;
 		/* high byte address going out first */
 		writel((addr >> (alen * 8)) & 0xff,
-		       &i2c_regs_p->ic_cmd_data);
+		       &i2c_base->ic_cmd_data);
 	}
 	return 0;
 }
 
-static int i2c_xfer_finish(void)
+static int i2c_xfer_finish(struct i2c_adapter *adap)
 {
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
 	ulong start_stop_det = get_timer(0);
 
 	while (1) {
-		if ((readl(&i2c_regs_p->ic_raw_intr_stat) & IC_STOP_DET)) {
-			readl(&i2c_regs_p->ic_clr_stop_det);
+		if ((readl(&i2c_base->ic_raw_intr_stat) & IC_STOP_DET)) {
+			readl(&i2c_base->ic_clr_stop_det);
 			break;
 		} else if (get_timer(start_stop_det) > I2C_STOPDET_TO) {
 			break;
 		}
 	}
 
-	if (i2c_wait_for_bb()) {
+	if (i2c_wait_for_bb(adap)) {
 		printf("Timed out waiting for bus\n");
 		return 1;
 	}
 
-	i2c_flush_rxfifo();
+	i2c_flush_rxfifo(adap);
 
 	return 0;
 }
@@ -249,8 +253,10 @@ static int i2c_xfer_finish(void)
  *
  * Read from i2c memory.
  */
-int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
+static int dw_i2c_read(struct i2c_adapter *adap, u8 dev, uint addr,
+		       int alen, u8 *buffer, int len)
 {
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
 	unsigned long start_time_rx;
 
 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
@@ -265,25 +271,25 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
 	 * still be one byte because the extra address bits are
 	 * hidden in the chip address.
 	 */
-	chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
+	dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
 	addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8));
 
-	debug("%s: fix addr_overflow: chip %02x addr %02x\n", __func__, chip,
+	debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev,
 	      addr);
 #endif
 
-	if (i2c_xfer_init(chip, addr, alen))
+	if (i2c_xfer_init(adap, dev, addr, alen))
 		return 1;
 
 	start_time_rx = get_timer(0);
 	while (len) {
 		if (len == 1)
-			writel(IC_CMD | IC_STOP, &i2c_regs_p->ic_cmd_data);
+			writel(IC_CMD | IC_STOP, &i2c_base->ic_cmd_data);
 		else
-			writel(IC_CMD, &i2c_regs_p->ic_cmd_data);
+			writel(IC_CMD, &i2c_base->ic_cmd_data);
 
-		if (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE) {
-			*buffer++ = (uchar)readl(&i2c_regs_p->ic_cmd_data);
+		if (readl(&i2c_base->ic_status) & IC_STATUS_RFNE) {
+			*buffer++ = (uchar)readl(&i2c_base->ic_cmd_data);
 			len--;
 			start_time_rx = get_timer(0);
 
@@ -292,7 +298,7 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
 		}
 	}
 
-	return i2c_xfer_finish();
+	return i2c_xfer_finish(adap);
 }
 
 /*
@@ -305,8 +311,10 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
  *
  * Write to i2c memory.
  */
-int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
+static int dw_i2c_write(struct i2c_adapter *adap, u8 dev, uint addr,
+			int alen, u8 *buffer, int len)
 {
+	struct i2c_regs *i2c_base = i2c_get_base(adap);
 	int nb = len;
 	unsigned long start_time_tx;
 
@@ -322,23 +330,25 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
 	 * still be one byte because the extra address bits are
 	 * hidden in the chip address.
 	 */
-	chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
+	dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
 	addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8));
 
-	debug("%s: fix addr_overflow: chip %02x addr %02x\n", __func__, chip,
+	debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev,
 	      addr);
 #endif
 
-	if (i2c_xfer_init(chip, addr, alen))
+	if (i2c_xfer_init(adap, dev, addr, alen))
 		return 1;
 
 	start_time_tx = get_timer(0);
 	while (len) {
-		if (readl(&i2c_regs_p->ic_status) & IC_STATUS_TFNF) {
-			if (--len == 0)
-				writel(*buffer | IC_STOP, &i2c_regs_p->ic_cmd_data);
-			else
-				writel(*buffer, &i2c_regs_p->ic_cmd_data);
+		if (readl(&i2c_base->ic_status) & IC_STATUS_TFNF) {
+			if (--len == 0) {
+				writel(*buffer | IC_STOP,
+				       &i2c_base->ic_cmd_data);
+			} else {
+				writel(*buffer, &i2c_base->ic_cmd_data);
+			}
 			buffer++;
 			start_time_tx = get_timer(0);
 
@@ -348,13 +358,13 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
 		}
 	}
 
-	return i2c_xfer_finish();
+	return i2c_xfer_finish(adap);
 }
 
 /*
  * i2c_probe - Probe the i2c chip
  */
-int i2c_probe(uchar chip)
+static int dw_i2c_probe(struct i2c_adapter *adap, u8 dev)
 {
 	u32 tmp;
 	int ret;
@@ -362,80 +372,31 @@ int i2c_probe(uchar chip)
 	/*
 	 * Try to read the first location of the chip.
 	 */
-	ret = i2c_read(chip, 0, 1, (uchar *)&tmp, 1);
+	ret = dw_i2c_read(adap, dev, 0, 1, (uchar *)&tmp, 1);
 	if (ret)
-		i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+		dw_i2c_init(adap, adap->speed, adap->slaveaddr);
 
 	return ret;
 }
 
-#ifdef CONFIG_I2C_MULTI_BUS
-int i2c_set_bus_num(unsigned int bus)
-{
-	switch (bus) {
-	case 0:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE;
-		break;
-#ifdef CONFIG_SYS_I2C_BASE1
-	case 1:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE1;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE2
-	case 2:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE2;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE3
-	case 3:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE3;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE4
-	case 4:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE4;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE5
-	case 5:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE5;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE6
-	case 6:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE6;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE7
-	case 7:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE7;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE8
-	case 8:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE8;
-		break;
-#endif
-#ifdef CONFIG_SYS_I2C_BASE9
-	case 9:
-		i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE9;
-		break;
-#endif
-	default:
-		printf("Bad bus: %d\n", bus);
-		return -1;
-	}
-
-	current_bus = bus;
+U_BOOT_I2C_ADAP_COMPLETE(dw_0, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
+			 dw_i2c_write, dw_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE, 0)
 
-	if (!bus_initialized[current_bus])
-		i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+#if CONFIG_SYS_I2C_BUS_MAX >= 2
+U_BOOT_I2C_ADAP_COMPLETE(dw_1, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
+			 dw_i2c_write, dw_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_SPEED1, CONFIG_SYS_I2C_SLAVE1, 1)
+#endif
 
-	return 0;
-}
+#if CONFIG_SYS_I2C_BUS_MAX >= 3
+U_BOOT_I2C_ADAP_COMPLETE(dw_2, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
+			 dw_i2c_write, dw_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_SPEED2, CONFIG_SYS_I2C_SLAVE2, 2)
+#endif
 
-unsigned int i2c_get_bus_num(void)
-{
-	return current_bus;
-}
+#if CONFIG_SYS_I2C_BUS_MAX >= 4
+U_BOOT_I2C_ADAP_COMPLETE(dw_3, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
+			 dw_i2c_write, dw_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_SPEED3, CONFIG_SYS_I2C_SLAVE3, 3)
 #endif