[U-Boot] [PATCH 09/12 v2] ARM: OMAP3: Add I2C support

dirk.behme at googlemail.com
2008-10-03T10:41:23Z

Subject: [PATCH 09/12 v2] ARM: OMAP3: Add I2C support

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

Add I2C support

Signed-off-by: Dirk Behme <dirk.behme@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;