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-rw-r--r--drivers/i2c/omap24xx_i2c.c475
-rw-r--r--drivers/i2c/omap24xx_i2c.h2
2 files changed, 174 insertions, 303 deletions
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index f06af02..a7ffd95 100644
--- a/drivers/i2c/omap24xx_i2c.c
+++ b/drivers/i2c/omap24xx_i2c.c
@@ -29,11 +29,10 @@
DECLARE_GLOBAL_DATA_PTR;
-#define I2C_STAT_TIMEO (1 << 31)
-#define I2C_TIMEOUT 10
+#define I2C_TIMEOUT 1000
-static u32 wait_for_bb(void);
-static u32 wait_for_status_mask(u16 mask);
+static void wait_for_bb(void);
+static u16 wait_for_pin(void);
static void flush_fifo(void);
/*
@@ -51,6 +50,7 @@ void i2c_init(int speed, int slaveadd)
int psc, fsscll, fssclh;
int hsscll = 0, hssclh = 0;
u32 scll, sclh;
+ int timeout = I2C_TIMEOUT;
/* Only handle standard, fast and high speeds */
if ((speed != OMAP_I2C_STANDARD) &&
@@ -112,14 +112,24 @@ void i2c_init(int speed, int slaveadd)
sclh = (unsigned int)fssclh;
}
- if (gd->flags & GD_FLG_RELOC)
- bus_initialized[current_bus] = 1;
-
if (readw(&i2c_base->con) & I2C_CON_EN) {
writew(0, &i2c_base->con);
udelay(50000);
}
+ writew(0x2, &i2c_base->sysc); /* for ES2 after soft reset */
+ udelay(1000);
+
+ writew(I2C_CON_EN, &i2c_base->con);
+ while (!(readw(&i2c_base->syss) & I2C_SYSS_RDONE) && timeout--) {
+ if (timeout <= 0) {
+ puts("ERROR: Timeout in soft-reset\n");
+ return;
+ }
+ udelay(1000);
+ }
+
+ writew(0, &i2c_base->con);
writew(psc, &i2c_base->psc);
writew(scll, &i2c_base->scll);
writew(sclh, &i2c_base->sclh);
@@ -135,6 +145,81 @@ void i2c_init(int speed, int slaveadd)
flush_fifo();
writew(0xFFFF, &i2c_base->stat);
writew(0, &i2c_base->cnt);
+
+ if (gd->flags & GD_FLG_RELOC)
+ bus_initialized[current_bus] = 1;
+}
+
+static int i2c_read_byte(u8 devaddr, u8 regoffset, u8 *value)
+{
+ int i2c_error = 0;
+ u16 status;
+
+ /* wait until bus not busy */
+ wait_for_bb();
+
+ /* one byte only */
+ writew(1, &i2c_base->cnt);
+ /* set slave address */
+ writew(devaddr, &i2c_base->sa);
+ /* no stop bit needed here */
+ writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
+ I2C_CON_TRX, &i2c_base->con);
+
+ /* send register offset */
+ while (1) {
+ status = wait_for_pin();
+ if (status == 0 || status & I2C_STAT_NACK) {
+ i2c_error = 1;
+ goto read_exit;
+ }
+ if (status & I2C_STAT_XRDY) {
+ /* Important: have to use byte access */
+ writeb(regoffset, &i2c_base->data);
+ writew(I2C_STAT_XRDY, &i2c_base->stat);
+ }
+ if (status & I2C_STAT_ARDY) {
+ writew(I2C_STAT_ARDY, &i2c_base->stat);
+ break;
+ }
+ }
+
+ /* set slave address */
+ writew(devaddr, &i2c_base->sa);
+ /* read one byte from slave */
+ writew(1, &i2c_base->cnt);
+ /* need stop bit here */
+ writew(I2C_CON_EN | I2C_CON_MST |
+ I2C_CON_STT | I2C_CON_STP,
+ &i2c_base->con);
+
+ /* receive data */
+ while (1) {
+ status = wait_for_pin();
+ if (status == 0 || status & I2C_STAT_NACK) {
+ i2c_error = 1;
+ goto read_exit;
+ }
+ if (status & I2C_STAT_RRDY) {
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
+ defined(CONFIG_OMAP44XX)
+ *value = readb(&i2c_base->data);
+#else
+ *value = readw(&i2c_base->data);
+#endif
+ writew(I2C_STAT_RRDY, &i2c_base->stat);
+ }
+ if (status & I2C_STAT_ARDY) {
+ writew(I2C_STAT_ARDY, &i2c_base->stat);
+ break;
+ }
+ }
+
+read_exit:
+ flush_fifo();
+ writew(0xFFFF, &i2c_base->stat);
+ writew(0, &i2c_base->cnt);
+ return i2c_error;
}
static void flush_fifo(void)
@@ -147,7 +232,7 @@ static void flush_fifo(void)
stat = readw(&i2c_base->stat);
if (stat == I2C_STAT_RRDY) {
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX)
+ defined(CONFIG_OMAP44XX)
readb(&i2c_base->data);
#else
readw(&i2c_base->data);
@@ -161,42 +246,32 @@ static void flush_fifo(void)
int i2c_probe(uchar chip)
{
- u32 status;
+ u16 status;
int res = 1; /* default = fail */
if (chip == readw(&i2c_base->oa))
return res;
/* wait until bus not busy */
- status = wait_for_bb();
- /* exit on BUS busy */
- if (status & I2C_STAT_TIMEO)
- return res;
+ wait_for_bb();
/* try to write one byte */
writew(1, &i2c_base->cnt);
/* set slave address */
writew(chip, &i2c_base->sa);
/* stop bit needed here */
- writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT
- | I2C_CON_STP, &i2c_base->con);
- /* enough delay for the NACK bit set */
- udelay(9000);
-
- if (!(readw(&i2c_base->stat) & I2C_STAT_NACK)) {
- res = 0; /* success case */
- flush_fifo();
- writew(0xFFFF, &i2c_base->stat);
- } else {
- /* failure, clear sources*/
- writew(0xFFFF, &i2c_base->stat);
- /* finish up xfer */
- writew(readw(&i2c_base->con) | I2C_CON_STP, &i2c_base->con);
- status = wait_for_bb();
- /* exit on BUS busy */
- if (status & I2C_STAT_TIMEO)
- return res;
- }
+ writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
+ I2C_CON_STP, &i2c_base->con);
+
+ status = wait_for_pin();
+
+ /* check for ACK (!NAK) */
+ if (!(status & I2C_STAT_NACK))
+ res = 0;
+
+ /* abort transfer (force idle state) */
+ writew(0, &i2c_base->con);
+
flush_fifo();
/* don't allow any more data in... we don't want it. */
writew(0, &i2c_base->cnt);
@@ -206,315 +281,111 @@ int i2c_probe(uchar chip)
int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
{
- int i2c_error = 0, i;
- u32 status;
+ int i;
- if ((alen > 2) || (alen < 0))
- return 1;
-
- if (alen < 2) {
- if (addr + len > 256)
- return 1;
- } else if (addr + len > 0xFFFF) {
+ if (alen > 1) {
+ printf("I2C read: addr len %d not supported\n", alen);
return 1;
}
- /* wait until bus not busy */
- status = wait_for_bb();
-
- /* exit on BUS busy */
- if (status & I2C_STAT_TIMEO)
+ if (addr + len > 256) {
+ puts("I2C read: address out of range\n");
return 1;
-
- writew((alen & 0xFF), &i2c_base->cnt);
- /* set slave address */
- writew(chip, &i2c_base->sa);
- /* Clear the Tx & Rx FIFOs */
- writew((readw(&i2c_base->buf) | I2C_RXFIFO_CLEAR |
- I2C_TXFIFO_CLEAR), &i2c_base->buf);
- /* no stop bit needed here */
- writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_TRX |
- I2C_CON_STT, &i2c_base->con);
-
- /* wait for Transmit ready condition */
- status = wait_for_status_mask(I2C_STAT_XRDY | I2C_STAT_NACK);
-
- if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
- i2c_error = 1;
-
- if (!i2c_error) {
- if (status & I2C_STAT_XRDY) {
- switch (alen) {
- case 2:
- /* Send address MSByte */
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_AM33XX)
- writew(((addr >> 8) & 0xFF), &i2c_base->data);
-
- /* Clearing XRDY event */
- writew((status & I2C_STAT_XRDY),
- &i2c_base->stat);
- /* wait for Transmit ready condition */
- status = wait_for_status_mask(I2C_STAT_XRDY |
- I2C_STAT_NACK);
-
- if (status & (I2C_STAT_NACK |
- I2C_STAT_TIMEO)) {
- i2c_error = 1;
- break;
- }
-#endif
- case 1:
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_AM33XX)
- /* Send address LSByte */
- writew((addr & 0xFF), &i2c_base->data);
-#else
- /* Send address Short word */
- writew((addr & 0xFFFF), &i2c_base->data);
-#endif
- /* Clearing XRDY event */
- writew((status & I2C_STAT_XRDY),
- &i2c_base->stat);
- /*wait for Transmit ready condition */
- status = wait_for_status_mask(I2C_STAT_ARDY |
- I2C_STAT_NACK);
-
- if (status & (I2C_STAT_NACK |
- I2C_STAT_TIMEO)) {
- i2c_error = 1;
- break;
- }
- }
- } else
- i2c_error = 1;
}
- /* Wait for ARDY to set */
- status = wait_for_status_mask(I2C_STAT_ARDY | I2C_STAT_NACK
- | I2C_STAT_AL);
-
- if (!i2c_error) {
- /* set slave address */
- writew(chip, &i2c_base->sa);
- writew((len & 0xFF), &i2c_base->cnt);
- /* Clear the Tx & Rx FIFOs */
- writew((readw(&i2c_base->buf) | I2C_RXFIFO_CLEAR |
- I2C_TXFIFO_CLEAR), &i2c_base->buf);
- /* need stop bit here */
- writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP,
- &i2c_base->con);
-
- for (i = 0; i < len; i++) {
- /* wait for Receive condition */
- status = wait_for_status_mask(I2C_STAT_RRDY |
- I2C_STAT_NACK);
- if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO)) {
- i2c_error = 1;
- break;
- }
-
- if (status & I2C_STAT_RRDY) {
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_AM33XX)
- buffer[i] = readb(&i2c_base->data);
-#else
- *((u16 *)&buffer[i]) =
- readw(&i2c_base->data) & 0xFFFF;
- i++;
-#endif
- writew((status & I2C_STAT_RRDY),
- &i2c_base->stat);
- udelay(1000);
- } else {
- i2c_error = 1;
- }
+ for (i = 0; i < len; i++) {
+ if (i2c_read_byte(chip, addr + i, &buffer[i])) {
+ puts("I2C read: I/O error\n");
+ i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+ return 1;
}
}
- /* Wait for ARDY to set */
- status = wait_for_status_mask(I2C_STAT_ARDY | I2C_STAT_NACK
- | I2C_STAT_AL);
-
- if (i2c_error) {
- writew(0, &i2c_base->con);
- return 1;
- }
-
- writew(I2C_CON_EN, &i2c_base->con);
-
- while (readw(&i2c_base->stat)
- || (readw(&i2c_base->con) & I2C_CON_MST)) {
- udelay(10000);
- writew(0xFFFF, &i2c_base->stat);
- }
-
- writew(I2C_CON_EN, &i2c_base->con);
- flush_fifo();
- writew(0xFFFF, &i2c_base->stat);
- writew(0, &i2c_base->cnt);
-
return 0;
}
int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
{
+ int i;
+ u16 status;
+ int i2c_error = 0;
- int i, i2c_error = 0;
- u32 status;
- u16 writelen;
-
- if (alen > 2)
+ if (alen > 1) {
+ printf("I2C write: addr len %d not supported\n", alen);
return 1;
+ }
- if (alen < 2) {
- if (addr + len > 256)
- return 1;
- } else if (addr + len > 0xFFFF) {
+ if (addr + len > 256) {
+ printf("I2C write: address 0x%x + 0x%x out of range\n",
+ addr, len);
return 1;
}
/* wait until bus not busy */
- status = wait_for_bb();
+ wait_for_bb();
- /* exiting on BUS busy */
- if (status & I2C_STAT_TIMEO)
- return 1;
-
- writelen = (len & 0xFFFF) + alen;
-
- /* two bytes */
- writew((writelen & 0xFFFF), &i2c_base->cnt);
- /* Clear the Tx & Rx FIFOs */
- writew((readw(&i2c_base->buf) | I2C_RXFIFO_CLEAR |
- I2C_TXFIFO_CLEAR), &i2c_base->buf);
+ /* start address phase - will write regoffset + len bytes data */
+ /* TODO consider case when !CONFIG_OMAP243X/34XX/44XX */
+ writew(alen + len, &i2c_base->cnt);
/* set slave address */
writew(chip, &i2c_base->sa);
/* stop bit needed here */
writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
I2C_CON_STP, &i2c_base->con);
- /* wait for Transmit ready condition */
- status = wait_for_status_mask(I2C_STAT_XRDY | I2C_STAT_NACK);
+ /* Send address byte */
+ status = wait_for_pin();
- if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
+ if (status == 0 || status & I2C_STAT_NACK) {
i2c_error = 1;
-
- if (!i2c_error) {
- if (status & I2C_STAT_XRDY) {
- switch (alen) {
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_AM33XX)
- case 2:
- /* send out MSB byte */
- writeb(((addr >> 8) & 0xFF), &i2c_base->data);
-#else
- writeb((addr & 0xFFFF), &i2c_base->data);
- break;
-#endif
- /* Clearing XRDY event */
- writew((status & I2C_STAT_XRDY),
- &i2c_base->stat);
- /*waiting for Transmit ready * condition */
- status = wait_for_status_mask(I2C_STAT_XRDY |
- I2C_STAT_NACK);
-
- if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO)) {
- i2c_error = 1;
- break;
- }
- case 1:
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_AM33XX)
- /* send out MSB byte */
- writeb((addr & 0xFF), &i2c_base->data);
-#else
- writew(((buffer[0] << 8) | (addr & 0xFF)),
- &i2c_base->data);
-#endif
- }
-
- /* Clearing XRDY event */
- writew((status & I2C_STAT_XRDY), &i2c_base->stat);
- }
-
- /* waiting for Transmit ready condition */
- status = wait_for_status_mask(I2C_STAT_XRDY | I2C_STAT_NACK);
-
- if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
- i2c_error = 1;
-
- if (!i2c_error) {
- for (i = ((alen > 1) ? 0 : 1); i < len; i++) {
- if (status & I2C_STAT_XRDY) {
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_AM33XX)
- writeb((buffer[i] & 0xFF),
- &i2c_base->data);
-#else
- writew((((buffer[i] << 8) |
- buffer[i + 1]) & 0xFFFF),
- &i2c_base->data);
- i++;
-#endif
- } else
- i2c_error = 1;
- /* Clearing XRDY event */
- writew((status & I2C_STAT_XRDY),
- &i2c_base->stat);
- /* waiting for XRDY condition */
- status = wait_for_status_mask(
- I2C_STAT_XRDY |
- I2C_STAT_ARDY |
- I2C_STAT_NACK);
- if (status & (I2C_STAT_NACK |
- I2C_STAT_TIMEO)) {
- i2c_error = 1;
- break;
- }
- if (status & I2C_STAT_ARDY)
- break;
- }
- }
+ printf("error waiting for i2c address ACK (status=0x%x)\n",
+ status);
+ goto write_exit;
}
- status = wait_for_status_mask(I2C_STAT_ARDY | I2C_STAT_NACK |
- I2C_STAT_AL);
-
- if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
+ if (status & I2C_STAT_XRDY) {
+ writeb(addr & 0xFF, &i2c_base->data);
+ writew(I2C_STAT_XRDY, &i2c_base->stat);
+ } else {
i2c_error = 1;
-
- if (i2c_error) {
- writew(0, &i2c_base->con);
- return 1;
+ printf("i2c bus not ready for transmit (status=0x%x)\n",
+ status);
+ goto write_exit;
}
- if (!i2c_error) {
- int eout = 200;
+ /* address phase is over, now write data */
+ for (i = 0; i < len; i++) {
+ status = wait_for_pin();
- writew(I2C_CON_EN, &i2c_base->con);
- while ((status = readw(&i2c_base->stat)) ||
- (readw(&i2c_base->con) & I2C_CON_MST)) {
- udelay(1000);
- /* have to read to clear intrrupt */
- writew(0xFFFF, &i2c_base->stat);
- if (--eout == 0)
- /* better leave with error than hang */
- break;
+ if (status == 0 || status & I2C_STAT_NACK) {
+ i2c_error = 1;
+ printf("i2c error waiting for data ACK (status=0x%x)\n",
+ status);
+ goto write_exit;
+ }
+
+ if (status & I2C_STAT_XRDY) {
+ writeb(buffer[i], &i2c_base->data);
+ writew(I2C_STAT_XRDY, &i2c_base->stat);
+ } else {
+ i2c_error = 1;
+ printf("i2c bus not ready for Tx (i=%d)\n", i);
+ goto write_exit;
}
}
+write_exit:
flush_fifo();
writew(0xFFFF, &i2c_base->stat);
- writew(0, &i2c_base->cnt);
- return 0;
+ return i2c_error;
}
-static u32 wait_for_bb(void)
+static void wait_for_bb(void)
{
int timeout = I2C_TIMEOUT;
- u32 stat;
+ u16 stat;
+ writew(0xFFFF, &i2c_base->stat); /* clear current interrupts...*/
while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
writew(stat, &i2c_base->stat);
udelay(1000);
@@ -523,28 +394,30 @@ static u32 wait_for_bb(void)
if (timeout <= 0) {
printf("timed out in wait_for_bb: I2C_STAT=%x\n",
readw(&i2c_base->stat));
- stat |= I2C_STAT_TIMEO;
}
writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/
- return stat;
}
-static u32 wait_for_status_mask(u16 mask)
+static u16 wait_for_pin(void)
{
- u32 status;
+ u16 status;
int timeout = I2C_TIMEOUT;
do {
udelay(1000);
status = readw(&i2c_base->stat);
- } while (!(status & mask) && timeout--);
+ } while (!(status &
+ (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
+ I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
+ I2C_STAT_AL)) && timeout--);
if (timeout <= 0) {
- printf("timed out in wait_for_status_mask: I2C_STAT=%x\n",
+ printf("timed out in wait_for_pin: I2C_STAT=%x\n",
readw(&i2c_base->stat));
writew(0xFFFF, &i2c_base->stat);
- status |= I2C_STAT_TIMEO;
+ status = 0;
}
+
return status;
}
diff --git a/drivers/i2c/omap24xx_i2c.h b/drivers/i2c/omap24xx_i2c.h
index 9a0b126..1f38c23 100644
--- a/drivers/i2c/omap24xx_i2c.h
+++ b/drivers/i2c/omap24xx_i2c.h
@@ -60,9 +60,7 @@
/* I2C Buffer Configuration Register (I2C_BUF): */
#define I2C_BUF_RDMA_EN (1 << 15) /* Receive DMA channel enable */
-#define I2C_RXFIFO_CLEAR (1 << 14) /* RX FIFO Clear */
#define I2C_BUF_XDMA_EN (1 << 7) /* Transmit DMA channel enable */
-#define I2C_TXFIFO_CLEAR (1 << 6) /* TX FIFO clear */
/* I2C Configuration Register (I2C_CON): */
generated by cgit v1.1 at 2024-12-29 09:12:57 +0000