[U-Boot] [PATCH v3 6/9] i2c, davinci: add support for multiple i2c buses

Murali Karicheri m-karicheri2 at ti.com
Fri Mar 21 21:51:35 CET 2014


From: Vitaly Andrianov <vitalya at ti.com>

Signed-off-by: Vitaly Andrianov <vitalya at ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2 at ti.com>
---
 drivers/i2c/davinci_i2c.c |  343 +++++++++++++++++++++++++++------------------
 drivers/i2c/davinci_i2c.h |   27 ++--
 2 files changed, 218 insertions(+), 152 deletions(-)

diff --git a/drivers/i2c/davinci_i2c.c b/drivers/i2c/davinci_i2c.c
index 6e5260c..c4a6c4d 100644
--- a/drivers/i2c/davinci_i2c.c
+++ b/drivers/i2c/davinci_i2c.c
@@ -1,8 +1,9 @@
 /*
  * TI DaVinci (TMS320DM644x) I2C driver.
  *
- * Copyright (C) 2007 Sergey Kubushyn <ksi at koi8.net>
- *
+ * (C) Copyright 2012-2014
+ *     Texas Instruments Incorporated, <www.ti.com>
+ * (C) Copyright 2007 Sergey Kubushyn <ksi at koi8.net>
  * --------------------------------------------------------
  *
  * SPDX-License-Identifier:	GPL-2.0+
@@ -12,14 +13,26 @@
 #include <i2c.h>
 #include <asm/arch/hardware.h>
 #include <asm/arch/i2c_defs.h>
+#include <asm/io.h>
 #include "davinci_i2c.h"
 
+DECLARE_GLOBAL_DATA_PTR;
+
+static struct i2c_regs __attribute__((section(".data"))) *i2c_base =
+						(struct i2c_regs *)I2C_BASE;
+
+#ifdef CONFIG_I2C_MULTI_BUS
+static unsigned int __attribute__((section(".data")))
+		bus_initialized[I2C_BUS_MAX] = { [0 ... (I2C_BUS_MAX-1)] = 0 };
+static unsigned int __attribute__((section(".data"))) current_bus;
+#endif
+
 #define CHECK_NACK() \
 	do {\
 		if (tmp & (I2C_TIMEOUT | I2C_STAT_NACK)) {\
-			REG(I2C_CON) = 0;\
-			return(1);\
-		}\
+			REG(&(i2c_base->i2c_con)) = 0;\
+			return 1;\
+		} \
 	} while (0)
 
 
@@ -27,20 +40,21 @@ static int wait_for_bus(void)
 {
 	int	stat, timeout;
 
-	REG(I2C_STAT) = 0xffff;
+	REG(&(i2c_base->i2c_stat)) = 0xffff;
 
 	for (timeout = 0; timeout < 10; timeout++) {
-		if (!((stat = REG(I2C_STAT)) & I2C_STAT_BB)) {
-			REG(I2C_STAT) = 0xffff;
-			return(0);
+		stat = REG(&(i2c_base->i2c_stat));
+		if (!((stat) & I2C_STAT_BB)) {
+			REG(&(i2c_base->i2c_stat)) = 0xffff;
+			return 0;
 		}
 
-		REG(I2C_STAT) = stat;
+		REG(&(i2c_base->i2c_stat)) = stat;
 		udelay(50000);
 	}
 
-	REG(I2C_STAT) = 0xffff;
-	return(1);
+	REG(&(i2c_base->i2c_stat)) = 0xffff;
+	return 1;
 }
 
 
@@ -50,25 +64,23 @@ static int poll_i2c_irq(int mask)
 
 	for (timeout = 0; timeout < 10; timeout++) {
 		udelay(1000);
-		stat = REG(I2C_STAT);
-		if (stat & mask) {
-			return(stat);
-		}
+		stat = REG(&(i2c_base->i2c_stat));
+		if (stat & mask)
+			return stat;
 	}
 
-	REG(I2C_STAT) = 0xffff;
-	return(stat | I2C_TIMEOUT);
+	REG(&(i2c_base->i2c_stat)) = 0xffff;
+	return stat | I2C_TIMEOUT;
 }
 
-
 void flush_rx(void)
 {
 	while (1) {
-		if (!(REG(I2C_STAT) & I2C_STAT_RRDY))
+		if (!(REG(&(i2c_base->i2c_stat)) & I2C_STAT_RRDY))
 			break;
 
-		REG(I2C_DRR);
-		REG(I2C_STAT) = I2C_STAT_RRDY;
+		REG(&(i2c_base->i2c_drr));
+		REG(&(i2c_base->i2c_stat)) = I2C_STAT_RRDY;
 		udelay(1000);
 	}
 }
@@ -78,28 +90,34 @@ void i2c_init(int speed, int slaveadd)
 {
 	u_int32_t	div, psc;
 
-	if (REG(I2C_CON) & I2C_CON_EN) {
-		REG(I2C_CON) = 0;
-		udelay (50000);
+	if (REG(&(i2c_base->i2c_con)) & I2C_CON_EN) {
+		REG(&(i2c_base->i2c_con)) = 0;
+		udelay(50000);
 	}
 
 	psc = 2;
-	div = (CONFIG_SYS_HZ_CLOCK / ((psc + 1) * speed)) - 10;	/* SCLL + SCLH */
-	REG(I2C_PSC) = psc;			/* 27MHz / (2 + 1) = 9MHz */
-	REG(I2C_SCLL) = (div * 50) / 100;	/* 50% Duty */
-	REG(I2C_SCLH) = div - REG(I2C_SCLL);
+	/* SCLL + SCLH */
+	div = (CONFIG_SYS_HZ_CLOCK / ((psc + 1) * speed)) - 10;
+	REG(&(i2c_base->i2c_psc)) = psc; /* 27MHz / (2 + 1) = 9MHz */
+	REG(&(i2c_base->i2c_scll)) = (div * 50) / 100; /* 50% Duty */
+	REG(&(i2c_base->i2c_sclh)) = div - REG(&(i2c_base->i2c_scll));
 
-	REG(I2C_OA) = slaveadd;
-	REG(I2C_CNT) = 0;
+	REG(&(i2c_base->i2c_oa)) = slaveadd;
+	REG(&(i2c_base->i2c_cnt)) = 0;
 
 	/* Interrupts must be enabled or I2C module won't work */
-	REG(I2C_IE) = I2C_IE_SCD_IE | I2C_IE_XRDY_IE |
+	REG(&(i2c_base->i2c_ie)) = I2C_IE_SCD_IE | I2C_IE_XRDY_IE |
 		I2C_IE_RRDY_IE | I2C_IE_ARDY_IE | I2C_IE_NACK_IE;
 
 	/* Now enable I2C controller (get it out of reset) */
-	REG(I2C_CON) = I2C_CON_EN;
+	REG(&(i2c_base->i2c_con)) = I2C_CON_EN;
 
 	udelay(1000);
+
+#ifdef CONFIG_I2C_MULTI_BUS
+	if (gd->flags & GD_FLG_RELOC)
+		bus_initialized[current_bus] = 1;
+#endif
 }
 
 int i2c_set_bus_speed(unsigned int speed)
@@ -112,34 +130,36 @@ int i2c_probe(u_int8_t chip)
 {
 	int	rc = 1;
 
-	if (chip == REG(I2C_OA)) {
-		return(rc);
-	}
+	if (chip == REG(&(i2c_base->i2c_oa)))
+		return rc;
 
-	REG(I2C_CON) = 0;
-	if (wait_for_bus()) {return(1);}
+	REG(&(i2c_base->i2c_con)) = 0;
+	if (wait_for_bus())
+		return 1;
 
 	/* try to read one byte from current (or only) address */
-	REG(I2C_CNT) = 1;
-	REG(I2C_SA) = chip;
-	REG(I2C_CON) = (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP);
-	udelay (50000);
+	REG(&(i2c_base->i2c_cnt)) = 1;
+	REG(&(i2c_base->i2c_sa))  = chip;
+	REG(&(i2c_base->i2c_con)) = (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
+				     I2C_CON_STP);
+	udelay(50000);
 
-	if (!(REG(I2C_STAT) & I2C_STAT_NACK)) {
+	if (!(REG(&(i2c_base->i2c_stat)) & I2C_STAT_NACK)) {
 		rc = 0;
 		flush_rx();
-		REG(I2C_STAT) = 0xffff;
+		REG(&(i2c_base->i2c_stat)) = 0xffff;
 	} else {
-		REG(I2C_STAT) = 0xffff;
-		REG(I2C_CON) |= I2C_CON_STP;
+		REG(&(i2c_base->i2c_stat)) = 0xffff;
+		REG(&(i2c_base->i2c_con)) |= I2C_CON_STP;
 		udelay(20000);
-		if (wait_for_bus()) {return(1);}
+		if (wait_for_bus())
+			return 1;
 	}
 
 	flush_rx();
-	REG(I2C_STAT) = 0xffff;
-	REG(I2C_CNT) = 0;
-	return(rc);
+	REG(&(i2c_base->i2c_stat)) = 0xffff;
+	REG(&(i2c_base->i2c_cnt)) = 0;
+	return rc;
 }
 
 
@@ -149,73 +169,76 @@ int i2c_read(u_int8_t chip, u_int32_t addr, int alen, u_int8_t *buf, int len)
 	int		i;
 
 	if ((alen < 0) || (alen > 2)) {
-		printf("%s(): bogus address length %x\n", __FUNCTION__, alen);
-		return(1);
+		printf("%s(): bogus address length %x\n", __func__, alen);
+		return 1;
 	}
 
-	if (wait_for_bus()) {return(1);}
+	if (wait_for_bus())
+		return 1;
 
 	if (alen != 0) {
 		/* Start address phase */
 		tmp = I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX;
-		REG(I2C_CNT) = alen;
-		REG(I2C_SA) = chip;
-		REG(I2C_CON) = tmp;
+		REG(&(i2c_base->i2c_cnt)) = alen;
+		REG(&(i2c_base->i2c_sa)) = chip;
+		REG(&(i2c_base->i2c_con)) = tmp;
 
 		tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK);
 
 		CHECK_NACK();
 
 		switch (alen) {
-			case 2:
-				/* Send address MSByte */
-				if (tmp & I2C_STAT_XRDY) {
-					REG(I2C_DXR) = (addr >> 8) & 0xff;
-				} else {
-					REG(I2C_CON) = 0;
-					return(1);
-				}
-
-				tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK);
-
-				CHECK_NACK();
-				/* No break, fall through */
-			case 1:
-				/* Send address LSByte */
-				if (tmp & I2C_STAT_XRDY) {
-					REG(I2C_DXR) = addr & 0xff;
-				} else {
-					REG(I2C_CON) = 0;
-					return(1);
-				}
-
-				tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK | I2C_STAT_ARDY);
-
-				CHECK_NACK();
-
-				if (!(tmp & I2C_STAT_ARDY)) {
-					REG(I2C_CON) = 0;
-					return(1);
-				}
+		case 2:
+			/* Send address MSByte */
+			if (tmp & I2C_STAT_XRDY) {
+				REG(&(i2c_base->i2c_dxr)) = (addr >> 8) & 0xff;
+			} else {
+				REG(&(i2c_base->i2c_con)) = 0;
+				return 1;
+			}
+
+			tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK);
+
+			CHECK_NACK();
+			/* No break, fall through */
+		case 1:
+			/* Send address LSByte */
+			if (tmp & I2C_STAT_XRDY) {
+				REG(&(i2c_base->i2c_dxr)) = addr & 0xff;
+			} else {
+				REG(&(i2c_base->i2c_con)) = 0;
+				return 1;
+			}
+
+			tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK |
+					   I2C_STAT_ARDY);
+
+			CHECK_NACK();
+
+			if (!(tmp & I2C_STAT_ARDY)) {
+				REG(&(i2c_base->i2c_con)) = 0;
+				return 1;
+			}
 		}
 	}
 
 	/* Address phase is over, now read 'len' bytes and stop */
 	tmp = I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP;
-	REG(I2C_CNT) = len & 0xffff;
-	REG(I2C_SA) = chip;
-	REG(I2C_CON) = tmp;
+	REG(&(i2c_base->i2c_cnt)) = len & 0xffff;
+	REG(&(i2c_base->i2c_sa)) = chip;
+	REG(&(i2c_base->i2c_con)) = tmp;
 
 	for (i = 0; i < len; i++) {
-		tmp = poll_i2c_irq(I2C_STAT_RRDY | I2C_STAT_NACK | I2C_STAT_ROVR);
+		tmp = poll_i2c_irq(I2C_STAT_RRDY | I2C_STAT_NACK |
+				   I2C_STAT_ROVR);
 
 		CHECK_NACK();
 
 		if (tmp & I2C_STAT_RRDY) {
-			buf[i] = REG(I2C_DRR);
+			buf[i] = REG(&(i2c_base->i2c_drr));
 		} else {
-			REG(I2C_CON) = 0;
-			return(1);
+			REG(&(i2c_base->i2c_con)) = 0;
+			return 1;
 		}
 	}
 
@@ -224,16 +247,16 @@ int i2c_read(u_int8_t chip, u_int32_t addr, int alen, u_int8_t *buf, int len)
 	CHECK_NACK();
 
 	if (!(tmp & I2C_STAT_SCD)) {
-		REG(I2C_CON) = 0;
-		return(1);
+		REG(&(i2c_base->i2c_con)) = 0;
+		return 1;
 	}
 
 	flush_rx();
-	REG(I2C_STAT) = 0xffff;
-	REG(I2C_CNT) = 0;
-	REG(I2C_CON) = 0;
+	REG(&(i2c_base->i2c_stat)) = 0xffff;
+	REG(&(i2c_base->i2c_cnt)) = 0;
+	REG(&(i2c_base->i2c_con)) = 0;
 
-	return(0);
+	return 0;
 }
 
 
@@ -243,48 +266,51 @@ int i2c_write(u_int8_t chip, u_int32_t addr, int alen, u_int8_t *buf, int len)
 	int		i;
 
 	if ((alen < 0) || (alen > 2)) {
-		printf("%s(): bogus address length %x\n", __FUNCTION__, alen);
-		return(1);
+		printf("%s(): bogus address length %x\n", __func__, alen);
+		return 1;
 	}
 	if (len < 0) {
-		printf("%s(): bogus length %x\n", __FUNCTION__, len);
-		return(1);
+		printf("%s(): bogus length %x\n", __func__, len);
+		return 1;
 	}
 
-	if (wait_for_bus()) {return(1);}
+	if (wait_for_bus())
+		return 1;
 
 	/* Start address phase */
-	tmp = I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX | I2C_CON_STP;
-	REG(I2C_CNT) = (alen == 0) ? len & 0xffff : (len & 0xffff) + alen;
-	REG(I2C_SA) = chip;
-	REG(I2C_CON) = tmp;
+	tmp = I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
+		I2C_CON_TRX | I2C_CON_STP;
+	REG(&(i2c_base->i2c_cnt)) = (alen == 0) ?
+		len & 0xffff : (len & 0xffff) + alen;
+	REG(&(i2c_base->i2c_sa)) = chip;
+	REG(&(i2c_base->i2c_con)) = tmp;
 
 	switch (alen) {
-		case 2:
-			/* Send address MSByte */
-			tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK);
+	case 2:
+		/* Send address MSByte */
+		tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK);
 
-			CHECK_NACK();
+		CHECK_NACK();
 
-			if (tmp & I2C_STAT_XRDY) {
-				REG(I2C_DXR) = (addr >> 8) & 0xff;
-			} else {
-				REG(I2C_CON) = 0;
-				return(1);
-			}
-			/* No break, fall through */
-		case 1:
-			/* Send address LSByte */
-			tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK);
+		if (tmp & I2C_STAT_XRDY) {
+			REG(&(i2c_base->i2c_dxr)) = (addr >> 8) & 0xff;
+		} else {
+			REG(&(i2c_base->i2c_con)) = 0;
+			return 1;
+		}
+		/* No break, fall through */
+	case 1:
+		/* Send address LSByte */
+		tmp = poll_i2c_irq(I2C_STAT_XRDY | I2C_STAT_NACK);
 
-			CHECK_NACK();
+		CHECK_NACK();
 
-			if (tmp & I2C_STAT_XRDY) {
-				REG(I2C_DXR) = addr & 0xff;
-			} else {
-				REG(I2C_CON) = 0;
-				return(1);
-			}
+		if (tmp & I2C_STAT_XRDY) {
+			REG(&(i2c_base->i2c_dxr)) = addr & 0xff;
+		} else {
+			REG(&(i2c_base->i2c_con)) = 0;
+			return 1;
+		}
 	}
 
 	for (i = 0; i < len; i++) {
@@ -292,11 +318,10 @@ int i2c_write(u_int8_t chip, u_int32_t addr, int alen, u_int8_t *buf, int len)
 
 		CHECK_NACK();
 
-		if (tmp & I2C_STAT_XRDY) {
-			REG(I2C_DXR) = buf[i];
-		} else {
-			return(1);
-		}
+		if (tmp & I2C_STAT_XRDY)
+			REG(&(i2c_base->i2c_dxr)) = buf[i];
+		else
+			return 1;
 	}
 
 	tmp = poll_i2c_irq(I2C_STAT_SCD | I2C_STAT_NACK);
@@ -304,14 +329,52 @@ int i2c_write(u_int8_t chip, u_int32_t addr, int alen, u_int8_t *buf, int len)
 	CHECK_NACK();
 
 	if (!(tmp & I2C_STAT_SCD)) {
-		REG(I2C_CON) = 0;
-		return(1);
+		REG(&(i2c_base->i2c_con)) = 0;
+		return 1;
 	}
 
 	flush_rx();
-	REG(I2C_STAT) = 0xffff;
-	REG(I2C_CNT) = 0;
-	REG(I2C_CON) = 0;
+	REG(&(i2c_base->i2c_stat)) = 0xffff;
+	REG(&(i2c_base->i2c_cnt)) = 0;
+	REG(&(i2c_base->i2c_con)) = 0;
+
+	return 0;
+}
+
+#ifdef CONFIG_I2C_MULTI_BUS
+int i2c_set_bus_num(unsigned int bus)
+{
+	if ((bus < 0) || (bus >= I2C_BUS_MAX)) {
+		printf("Bad bus: %d\n", bus);
+		return -1;
+	}
+
+	switch (bus) {
+#if I2C_BUS_MAX == 3
+	case 2:
+		i2c_base = (struct i2c_regs *)I2C2_BASE;
+		break;
+#endif
+#if I2C_BUS_MAX >= 2
+	case 1:
+		i2c_base = (struct i2c_regs *)I2C1_BASE;
+		break;
+#endif
+	default:
+		i2c_base = (struct i2c_regs *)I2C0_BASE;
+		bus = 0;
+	}
+
+	current_bus = bus;
+
+	if (!bus_initialized[current_bus])
+		i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
 
-	return(0);
+	return 0;
+}
+
+unsigned int i2c_get_bus_num(void)
+{
+	return (int) current_bus;
 }
+#endif
diff --git a/drivers/i2c/davinci_i2c.h b/drivers/i2c/davinci_i2c.h
index 79ff7a3..20d4342 100644
--- a/drivers/i2c/davinci_i2c.h
+++ b/drivers/i2c/davinci_i2c.h
@@ -12,18 +12,21 @@
 #define I2C_WRITE		0
 #define I2C_READ		1
 
-#define	I2C_OA			(I2C_BASE + 0x00)
-#define I2C_IE			(I2C_BASE + 0x04)
-#define I2C_STAT		(I2C_BASE + 0x08)
-#define I2C_SCLL		(I2C_BASE + 0x0c)
-#define I2C_SCLH		(I2C_BASE + 0x10)
-#define I2C_CNT			(I2C_BASE + 0x14)
-#define I2C_DRR			(I2C_BASE + 0x18)
-#define I2C_SA			(I2C_BASE + 0x1c)
-#define I2C_DXR			(I2C_BASE + 0x20)
-#define I2C_CON			(I2C_BASE + 0x24)
-#define I2C_IV			(I2C_BASE + 0x28)
-#define I2C_PSC			(I2C_BASE + 0x30)
+struct i2c_regs {
+	u32	i2c_oa;
+	u32	i2c_ie;
+	u32	i2c_stat;
+	u32	i2c_scll;
+	u32	i2c_sclh;
+	u32	i2c_cnt;
+	u32	i2c_drr;
+	u32	i2c_sa;
+	u32	i2c_dxr;
+	u32	i2c_con;
+	u32	i2c_iv;
+	u32	res_2c;
+	u32	i2c_psc;
+};
 
 /* I2C masks */
 
-- 
1.7.9.5



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