OMAP2/3: I2C: Add support for second and third bus
Add support to use second and third I2C bus, too.
Bus 0 is still the default, but by calling i2c_set_bus_num(1/2) before doing
I2C accesses, code can switch to bus 1 and 2, too. Don't forget to switch
back afterwards, then.
Signed-off-by: Dirk Behme <dirk.behme@googlemail.com>
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index 1a4c8c9..ff18991 100644
--- a/drivers/i2c/omap24xx_i2c.c
+++ b/drivers/i2c/omap24xx_i2c.c
@@ -29,6 +29,11 @@
static u16 wait_for_pin (void);
static void flush_fifo(void);
+static struct i2c *i2c_base = (struct i2c *)I2C_DEFAULT_BASE;
+
+static unsigned int bus_initialized[I2C_BUS_MAX];
+static unsigned int current_bus;
+
void i2c_init (int speed, int slaveadd)
{
int psc, fsscll, fssclh;
@@ -95,30 +100,32 @@
sclh = (unsigned int)fssclh;
}
- writew(0x2, I2C_SYSC); /* for ES2 after soft reset */
+ writew(0x2, &i2c_base->sysc); /* for ES2 after soft reset */
udelay(1000);
- writew(0x0, I2C_SYSC); /* will probably self clear but */
+ writew(0x0, &i2c_base->sysc); /* will probably self clear but */
- if (readw (I2C_CON) & I2C_CON_EN) {
- writew (0, I2C_CON);
+ if (readw (&i2c_base->con) & I2C_CON_EN) {
+ writew (0, &i2c_base->con);
udelay (50000);
}
- writew(psc, I2C_PSC);
- writew(scll, I2C_SCLL);
- writew(sclh, I2C_SCLH);
+ writew(psc, &i2c_base->psc);
+ writew(scll, &i2c_base->scll);
+ writew(sclh, &i2c_base->sclh);
/* own address */
- writew (slaveadd, I2C_OA);
- writew (I2C_CON_EN, I2C_CON);
+ writew (slaveadd, &i2c_base->oa);
+ writew (I2C_CON_EN, &i2c_base->con);
/* have to enable intrrupts or OMAP i2c module doesn't work */
writew (I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
- I2C_IE_NACK_IE | I2C_IE_AL_IE, I2C_IE);
+ I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
udelay (1000);
flush_fifo();
- writew (0xFFFF, I2C_STAT);
- writew (0, I2C_CNT);
+ writew (0xFFFF, &i2c_base->stat);
+ writew (0, &i2c_base->cnt);
+
+ bus_initialized[current_bus] = 1;
}
static int i2c_read_byte (u8 devaddr, u8 regoffset, u8 * value)
@@ -130,19 +137,19 @@
wait_for_bb ();
/* one byte only */
- writew (1, I2C_CNT);
+ writew (1, &i2c_base->cnt);
/* set slave address */
- writew (devaddr, I2C_SA);
+ writew (devaddr, &i2c_base->sa);
/* no stop bit needed here */
- writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX, I2C_CON);
+ writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX, &i2c_base->con);
status = wait_for_pin ();
if (status & I2C_STAT_XRDY) {
/* Important: have to use byte access */
- writeb (regoffset, I2C_DATA);
+ writeb (regoffset, &i2c_base->data);
udelay (20000);
- if (readw (I2C_STAT) & I2C_STAT_NACK) {
+ if (readw (&i2c_base->stat) & I2C_STAT_NACK) {
i2c_error = 1;
}
} else {
@@ -151,28 +158,28 @@
if (!i2c_error) {
/* free bus, otherwise we can't use a combined transction */
- writew (0, I2C_CON);
- while (readw (I2C_STAT) || (readw (I2C_CON) & I2C_CON_MST)) {
+ writew (0, &i2c_base->con);
+ while (readw (&i2c_base->stat) || (readw (&i2c_base->con) & I2C_CON_MST)) {
udelay (10000);
/* Have to clear pending interrupt to clear I2C_STAT */
- writew (0xFFFF, I2C_STAT);
+ writew (0xFFFF, &i2c_base->stat);
}
wait_for_bb ();
/* set slave address */
- writew (devaddr, I2C_SA);
+ writew (devaddr, &i2c_base->sa);
/* read one byte from slave */
- writew (1, I2C_CNT);
+ writew (1, &i2c_base->cnt);
/* need stop bit here */
writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP,
- I2C_CON);
+ &i2c_base->con);
status = wait_for_pin ();
if (status & I2C_STAT_RRDY) {
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
- *value = readb (I2C_DATA);
+ *value = readb (&i2c_base->data);
#else
- *value = readw (I2C_DATA);
+ *value = readw (&i2c_base->data);
#endif
udelay (20000);
} else {
@@ -180,17 +187,17 @@
}
if (!i2c_error) {
- writew (I2C_CON_EN, I2C_CON);
- while (readw (I2C_STAT)
- || (readw (I2C_CON) & I2C_CON_MST)) {
+ writew (I2C_CON_EN, &i2c_base->con);
+ while (readw (&i2c_base->stat)
+ || (readw (&i2c_base->con) & I2C_CON_MST)) {
udelay (10000);
- writew (0xFFFF, I2C_STAT);
+ writew (0xFFFF, &i2c_base->stat);
}
}
}
flush_fifo();
- writew (0xFFFF, I2C_STAT);
- writew (0, I2C_CNT);
+ writew (0xFFFF, &i2c_base->stat);
+ writew (0, &i2c_base->cnt);
return i2c_error;
}
@@ -203,12 +210,12 @@
wait_for_bb ();
/* two bytes */
- writew (2, I2C_CNT);
+ writew (2, &i2c_base->cnt);
/* set slave address */
- writew (devaddr, I2C_SA);
+ writew (devaddr, &i2c_base->sa);
/* stop bit needed here */
writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
- I2C_CON_STP, I2C_CON);
+ I2C_CON_STP, &i2c_base->con);
/* wait until state change */
status = wait_for_pin ();
@@ -216,24 +223,24 @@
if (status & I2C_STAT_XRDY) {
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
/* send out 1 byte */
- writeb (regoffset, I2C_DATA);
- writew (I2C_STAT_XRDY, I2C_STAT);
+ writeb (regoffset, &i2c_base->data);
+ writew (I2C_STAT_XRDY, &i2c_base->stat);
status = wait_for_pin ();
if ((status & I2C_STAT_XRDY)) {
/* send out next 1 byte */
- writeb (value, I2C_DATA);
- writew (I2C_STAT_XRDY, I2C_STAT);
+ writeb (value, &i2c_base->data);
+ writew (I2C_STAT_XRDY, &i2c_base->stat);
} else {
i2c_error = 1;
}
#else
/* send out two bytes */
- writew ((value << 8) + regoffset, I2C_DATA);
+ writew ((value << 8) + regoffset, &i2c_base->data);
#endif
/* must have enough delay to allow BB bit to go low */
udelay (50000);
- if (readw (I2C_STAT) & I2C_STAT_NACK) {
+ if (readw (&i2c_base->stat) & I2C_STAT_NACK) {
i2c_error = 1;
}
} else {
@@ -243,18 +250,18 @@
if (!i2c_error) {
int eout = 200;
- writew (I2C_CON_EN, I2C_CON);
- while ((stat = readw (I2C_STAT)) || (readw (I2C_CON) & I2C_CON_MST)) {
+ writew (I2C_CON_EN, &i2c_base->con);
+ while ((stat = readw (&i2c_base->stat)) || (readw (&i2c_base->con) & I2C_CON_MST)) {
udelay (1000);
/* have to read to clear intrrupt */
- writew (0xFFFF, I2C_STAT);
+ writew (0xFFFF, &i2c_base->stat);
if(--eout == 0) /* better leave with error than hang */
break;
}
}
flush_fifo();
- writew (0xFFFF, I2C_STAT);
- writew (0, I2C_CNT);
+ writew (0xFFFF, &i2c_base->stat);
+ writew (0, &i2c_base->cnt);
return i2c_error;
}
@@ -265,14 +272,14 @@
* you get a bus error
*/
while(1){
- stat = readw(I2C_STAT);
+ stat = readw(&i2c_base->stat);
if(stat == I2C_STAT_RRDY){
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
- readb(I2C_DATA);
+ readb(&i2c_base->data);
#else
- readw(I2C_DATA);
+ readw(&i2c_base->data);
#endif
- writew(I2C_STAT_RRDY,I2C_STAT);
+ writew(I2C_STAT_RRDY,&i2c_base->stat);
udelay(1000);
}else
break;
@@ -283,7 +290,7 @@
{
int res = 1; /* default = fail */
- if (chip == readw (I2C_OA)) {
+ if (chip == readw (&i2c_base->oa)) {
return res;
}
@@ -291,27 +298,27 @@
wait_for_bb ();
/* try to read one byte */
- writew (1, I2C_CNT);
+ writew (1, &i2c_base->cnt);
/* set slave address */
- writew (chip, I2C_SA);
+ writew (chip, &i2c_base->sa);
/* stop bit needed here */
- writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP, I2C_CON);
+ writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP, &i2c_base->con);
/* enough delay for the NACK bit set */
udelay (50000);
- if (!(readw (I2C_STAT) & I2C_STAT_NACK)) {
+ if (!(readw (&i2c_base->stat) & I2C_STAT_NACK)) {
res = 0; /* success case */
flush_fifo();
- writew(0xFFFF, I2C_STAT);
+ writew(0xFFFF, &i2c_base->stat);
} else {
- writew(0xFFFF, I2C_STAT); /* failue, clear sources*/
- writew (readw (I2C_CON) | I2C_CON_STP, I2C_CON); /* finish up xfer */
+ writew(0xFFFF, &i2c_base->stat); /* failue, clear sources*/
+ writew (readw (&i2c_base->con) | I2C_CON_STP, &i2c_base->con); /* finish up xfer */
udelay(20000);
wait_for_bb ();
}
flush_fifo();
- writew (0, I2C_CNT); /* don't allow any more data in...we don't want it.*/
- writew(0xFFFF, I2C_STAT);
+ writew (0, &i2c_base->cnt); /* don't allow any more data in...we don't want it.*/
+ writew(0xFFFF, &i2c_base->stat);
return res;
}
@@ -370,17 +377,17 @@
int timeout = 10;
u16 stat;
- writew(0xFFFF, I2C_STAT); /* clear current interruts...*/
- while ((stat = readw (I2C_STAT) & I2C_STAT_BB) && timeout--) {
- writew (stat, I2C_STAT);
+ writew(0xFFFF, &i2c_base->stat); /* clear current interruts...*/
+ while ((stat = readw (&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
+ writew (stat, &i2c_base->stat);
udelay (50000);
}
if (timeout <= 0) {
printf ("timed out in wait_for_bb: I2C_STAT=%x\n",
- readw (I2C_STAT));
+ readw (&i2c_base->stat));
}
- writew(0xFFFF, I2C_STAT); /* clear delayed stuff*/
+ writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/
}
static u16 wait_for_pin (void)
@@ -390,7 +397,7 @@
do {
udelay (1000);
- status = readw (I2C_STAT);
+ status = readw (&i2c_base->stat);
} while ( !(status &
(I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
@@ -398,8 +405,33 @@
if (timeout <= 0) {
printf ("timed out in wait_for_pin: I2C_STAT=%x\n",
- readw (I2C_STAT));
- writew(0xFFFF, I2C_STAT);
+ readw (&i2c_base->stat));
+ writew(0xFFFF, &i2c_base->stat);
}
return status;
}
+
+int i2c_set_bus_num(unsigned int bus)
+{
+ if ((bus < 0) || (bus >= I2C_BUS_MAX)) {
+ printf("Bad bus: %d\n", bus);
+ return -1;
+ }
+
+#if I2C_BUS_MAX==3
+ if (bus == 2)
+ i2c_base = (struct i2c *)I2C_BASE3;
+ else
+#endif
+ if (bus == 1)
+ i2c_base = (struct i2c *)I2C_BASE2;
+ else
+ i2c_base = (struct i2c *)I2C_BASE1;
+
+ current_bus = bus;
+
+ if(!bus_initialized[current_bus])
+ i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+
+ return 0;
+}