[U-Boot] [PATCH 10/13 v3] ARM: OMAP3: Add I2C support

dirk.behme at googlemail.com dirk.behme at googlemail.com
Thu Oct 9 19:56:17 CEST 2008


Subject: [PATCH 10/13 v3] ARM: OMAP3: Add I2C support

From: Dirk Behme <dirk.behme at gmail.com>

Add I2C support

Signed-off-by: Dirk Behme <dirk.behme at gmail.com>

---
Changes in version v2:

- Remove SMC911X network init as proposed by Ben Warren. Thanks!

 drivers/i2c/Makefile       |    1 
 drivers/i2c/omap24xx_i2c.c |  132 ++++++++++++++++++++++++++-------------------
 drivers/net/Makefile       |    1 
 3 files changed, 80 insertions(+), 54 deletions(-)

Index: u-boot-arm/drivers/i2c/Makefile
===================================================================
--- u-boot-arm.orig/drivers/i2c/Makefile
+++ u-boot-arm/drivers/i2c/Makefile
@@ -29,6 +29,7 @@ COBJS-$(CONFIG_FSL_I2C) += fsl_i2c.o
 COBJS-$(CONFIG_I2C_MXC) += mxc_i2c.o
 COBJS-$(CONFIG_DRIVER_OMAP1510_I2C) += omap1510_i2c.o
 COBJS-$(CONFIG_DRIVER_OMAP24XX_I2C) += omap24xx_i2c.o
+COBJS-$(CONFIG_DRIVER_OMAP34XX_I2C) += omap24xx_i2c.o
 COBJS-$(CONFIG_SOFT_I2C) += soft_i2c.o
 COBJS-$(CONFIG_TSI108_I2C) += tsi108_i2c.o
 
Index: u-boot-arm/drivers/i2c/omap24xx_i2c.c
===================================================================
--- u-boot-arm.orig/drivers/i2c/omap24xx_i2c.c
+++ u-boot-arm/drivers/i2c/omap24xx_i2c.c
@@ -25,8 +25,10 @@
 #include <asm/arch/i2c.h>
 #include <asm/io.h>
 
+#define inb(a) __raw_readb(a)
+#define outb(a, v) __raw_writeb(a, v)
 #define inw(a) __raw_readw(a)
-#define outw(a,v) __raw_writew(a,v)
+#define outw(a, v) __raw_writew(a, v)
 
 static void wait_for_bb (void);
 static u16 wait_for_pin (void);
@@ -40,28 +42,28 @@ void i2c_init (int speed, int slaveadd)
 	udelay(1000);
 	outw(0x0, I2C_SYSC); /* will probably self clear but */
 
-	if (inw (I2C_CON) & I2C_CON_EN) {
-		outw (0, I2C_CON);
+	if (inw(I2C_CON) & I2C_CON_EN) {
+		outw(0, I2C_CON);
 		udelay (50000);
 	}
 
 	/* 12Mhz I2C module clock */
-	outw (0, I2C_PSC);
+	outw(0, I2C_PSC);
 	speed = speed/1000;		    /* 100 or 400 */
 	scl = ((12000/(speed*2)) - 7);	/* use 7 when PSC = 0 */
-	outw (scl, I2C_SCLL);
-	outw (scl, I2C_SCLH);
+	outw(scl, I2C_SCLL);
+	outw(scl, I2C_SCLH);
 	/* own address */
-	outw (slaveadd, I2C_OA);
-	outw (I2C_CON_EN, I2C_CON);
+	outw(slaveadd, I2C_OA);
+	outw(I2C_CON_EN, I2C_CON);
 
 	/* have to enable intrrupts or OMAP i2c module doesn't work */
-	outw (I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
-	      I2C_IE_NACK_IE | I2C_IE_AL_IE, I2C_IE);
+	outw(I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
+	     I2C_IE_NACK_IE | I2C_IE_AL_IE, I2C_IE);
 	udelay (1000);
 	flush_fifo();
-	outw (0xFFFF, I2C_STAT);
-	outw (0, I2C_CNT);
+	outw(0xFFFF, I2C_STAT);
+	outw(0, I2C_CNT);
 }
 
 static int i2c_read_byte (u8 devaddr, u8 regoffset, u8 * value)
@@ -73,11 +75,11 @@ static int i2c_read_byte (u8 devaddr, u8
 	wait_for_bb ();
 
 	/* one byte only */
-	outw (1, I2C_CNT);
+	outw(1, I2C_CNT);
 	/* set slave address */
-	outw (devaddr, I2C_SA);
+	outw(devaddr, I2C_SA);
 	/* no stop bit needed here */
-	outw (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX, I2C_CON);
+	outw(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX, I2C_CON);
 
 	status = wait_for_pin ();
 
@@ -85,7 +87,7 @@ static int i2c_read_byte (u8 devaddr, u8
 		/* Important: have to use byte access */
 		*(volatile u8 *) (I2C_DATA) = regoffset;
 		udelay (20000);
-		if (inw (I2C_STAT) & I2C_STAT_NACK) {
+		if (inw(I2C_STAT) & I2C_STAT_NACK) {
 			i2c_error = 1;
 		}
 	} else {
@@ -94,42 +96,46 @@ static int i2c_read_byte (u8 devaddr, u8
 
 	if (!i2c_error) {
 		/* free bus, otherwise we can't use a combined transction */
-		outw (0, I2C_CON);
-		while (inw (I2C_STAT) || (inw (I2C_CON) & I2C_CON_MST)) {
+		outw(0, I2C_CON);
+		while (inw(I2C_STAT) || (inw(I2C_CON) & I2C_CON_MST)) {
 			udelay (10000);
 			/* Have to clear pending interrupt to clear I2C_STAT */
-			outw (0xFFFF, I2C_STAT);
+			outw(0xFFFF, I2C_STAT);
 		}
 
 		wait_for_bb ();
 		/* set slave address */
-		outw (devaddr, I2C_SA);
+		outw(devaddr, I2C_SA);
 		/* read one byte from slave */
-		outw (1, I2C_CNT);
+		outw(1, I2C_CNT);
 		/* need stop bit here */
-		outw (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP,
-		      I2C_CON);
+		outw(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP,
+		     I2C_CON);
 
 		status = wait_for_pin ();
 		if (status & I2C_STAT_RRDY) {
-			*value = inw (I2C_DATA);
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+			*value = inb(I2C_DATA);
+#else
+			*value = inw(I2C_DATA);
+#endif
 			udelay (20000);
 		} else {
 			i2c_error = 1;
 		}
 
 		if (!i2c_error) {
-			outw (I2C_CON_EN, I2C_CON);
-			while (inw (I2C_STAT)
-			       || (inw (I2C_CON) & I2C_CON_MST)) {
+			outw(I2C_CON_EN, I2C_CON);
+			while (inw(I2C_STAT)
+			       || (inw(I2C_CON) & I2C_CON_MST)) {
 				udelay (10000);
-				outw (0xFFFF, I2C_STAT);
+				outw(0xFFFF, I2C_STAT);
 			}
 		}
 	}
 	flush_fifo();
-	outw (0xFFFF, I2C_STAT);
-	outw (0, I2C_CNT);
+	outw(0xFFFF, I2C_STAT);
+	outw(0, I2C_CNT);
 	return i2c_error;
 }
 
@@ -142,22 +148,37 @@ static int i2c_write_byte (u8 devaddr, u
 	wait_for_bb ();
 
 	/* two bytes */
-	outw (2, I2C_CNT);
+	outw(2, I2C_CNT);
 	/* set slave address */
-	outw (devaddr, I2C_SA);
+	outw(devaddr, I2C_SA);
 	/* stop bit needed here */
-	outw (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
-	      I2C_CON_STP, I2C_CON);
+	outw(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
+	     I2C_CON_STP, I2C_CON);
 
 	/* wait until state change */
 	status = wait_for_pin ();
 
 	if (status & I2C_STAT_XRDY) {
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+		/* send out 1 byte */
+		outb(regoffset, I2C_DATA);
+		outw(I2C_STAT_XRDY, I2C_STAT);
+		status = wait_for_pin();
+		if ((status & I2C_STAT_XRDY)) {
+			/* send out next 1 byte */
+			outb(value, I2C_DATA);
+			outw(I2C_STAT_XRDY, I2C_STAT);
+		} else {
+			i2c_error = 1;
+		}
+#else
 		/* send out two bytes */
-		outw ((value << 8) + regoffset, I2C_DATA);
+		outw((value << 8) + regoffset, I2C_DATA);
+#endif
+
 		/* must have enough delay to allow BB bit to go low */
 		udelay (50000);
-		if (inw (I2C_STAT) & I2C_STAT_NACK) {
+		if (inw(I2C_STAT) & I2C_STAT_NACK) {
 			i2c_error = 1;
 		}
 	} else {
@@ -167,18 +188,18 @@ static int i2c_write_byte (u8 devaddr, u
 	if (!i2c_error) {
 		int eout = 200;
 
-		outw (I2C_CON_EN, I2C_CON);
-		while ((stat = inw (I2C_STAT)) || (inw (I2C_CON) & I2C_CON_MST)) {
+		outw(I2C_CON_EN, I2C_CON);
+		while ((stat = inw(I2C_STAT)) || (inw(I2C_CON) & I2C_CON_MST)) {
 			udelay (1000);
 			/* have to read to clear intrrupt */
-			outw (0xFFFF, I2C_STAT);
+			outw(0xFFFF, I2C_STAT);
 			if(--eout == 0) /* better leave with error than hang */
 				break;
 		}
 	}
 	flush_fifo();
-	outw (0xFFFF, I2C_STAT);
-	outw (0, I2C_CNT);
+	outw(0xFFFF, I2C_STAT);
+	outw(0, I2C_CNT);
 	return i2c_error;
 }
 
@@ -191,7 +212,11 @@ static void flush_fifo(void)
 	while(1){
 		stat = inw(I2C_STAT);
 		if(stat == I2C_STAT_RRDY){
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+			inb(I2C_DATA);
+#else
 			inw(I2C_DATA);
+#endif
 			outw(I2C_STAT_RRDY,I2C_STAT);
 			udelay(1000);
 		}else
@@ -203,34 +228,33 @@ int i2c_probe (uchar chip)
 {
 	int res = 1; /* default = fail */
 
-	if (chip == inw (I2C_OA)) {
+	if (chip == inw(I2C_OA))
 		return res;
-	}
 
 	/* wait until bus not busy */
 	wait_for_bb ();
 
 	/* try to read one byte */
-	outw (1, I2C_CNT);
+	outw(1, I2C_CNT);
 	/* set slave address */
-	outw (chip, I2C_SA);
+	outw(chip, I2C_SA);
 	/* stop bit needed here */
-	outw (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP, I2C_CON);
+	outw(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP, I2C_CON);
 	/* enough delay for the NACK bit set */
 	udelay (50000);
 
-	if (!(inw (I2C_STAT) & I2C_STAT_NACK)) {
+	if (!(inw(I2C_STAT) & I2C_STAT_NACK)) {
 		res = 0;      /* success case */
 		flush_fifo();
 		outw(0xFFFF, I2C_STAT);
 	} else {
 		outw(0xFFFF, I2C_STAT);	 /* failue, clear sources*/
-		outw (inw (I2C_CON) | I2C_CON_STP, I2C_CON); /* finish up xfer */
+		outw(inw(I2C_CON) | I2C_CON_STP, I2C_CON); /* finish up xfer */
 		udelay(20000);
 		wait_for_bb ();
 	}
 	flush_fifo();
-	outw (0, I2C_CNT); /* don't allow any more data in...we don't want it.*/
+	outw(0, I2C_CNT); /* don't allow any more data in...we don't want it.*/
 	outw(0xFFFF, I2C_STAT);
 	return res;
 }
@@ -291,14 +315,14 @@ static void wait_for_bb (void)
 	u16 stat;
 
 	outw(0xFFFF, I2C_STAT);	 /* clear current interruts...*/
-	while ((stat = inw (I2C_STAT) & I2C_STAT_BB) && timeout--) {
-		outw (stat, I2C_STAT);
+	while ((stat = inw(I2C_STAT) & I2C_STAT_BB) && timeout--) {
+		outw(stat, I2C_STAT);
 		udelay (50000);
 	}
 
 	if (timeout <= 0) {
 		printf ("timed out in wait_for_bb: I2C_STAT=%x\n",
-			inw (I2C_STAT));
+			inw(I2C_STAT));
 	}
 	outw(0xFFFF, I2C_STAT);	 /* clear delayed stuff*/
 }
@@ -310,7 +334,7 @@ static u16 wait_for_pin (void)
 
 	do {
 		udelay (1000);
-		status = inw (I2C_STAT);
+		status = inw(I2C_STAT);
 	} while (  !(status &
 		   (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
 		    I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
@@ -318,7 +342,7 @@ static u16 wait_for_pin (void)
 
 	if (timeout <= 0) {
 		printf ("timed out in wait_for_pin: I2C_STAT=%x\n",
-			inw (I2C_STAT));
+			inw(I2C_STAT));
 			outw(0xFFFF, I2C_STAT);
 }
 	return status;



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