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path: root/drivers/i2c/busses/i2c-omap.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-omap.c')
-rw-r--r--drivers/i2c/busses/i2c-omap.c54
1 files changed, 45 insertions, 9 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index fdd83277c8a..827da085813 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -672,9 +672,17 @@ omap_i2c_isr(int this_irq, void *dev_id)
break;
}
- omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
-
err = 0;
+complete:
+ /*
+ * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
+ * acked after the data operation is complete.
+ * Ref: TRM SWPU114Q Figure 18-31
+ */
+ omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
+ ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
+ OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
+
if (stat & OMAP_I2C_STAT_NACK) {
err |= OMAP_I2C_STAT_NACK;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
@@ -685,16 +693,22 @@ omap_i2c_isr(int this_irq, void *dev_id)
err |= OMAP_I2C_STAT_AL;
}
if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
- OMAP_I2C_STAT_AL))
+ OMAP_I2C_STAT_AL)) {
+ omap_i2c_ack_stat(dev, stat &
+ (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
+ OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
omap_i2c_complete_cmd(dev, err);
+ return IRQ_HANDLED;
+ }
if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
u8 num_bytes = 1;
if (dev->fifo_size) {
if (stat & OMAP_I2C_STAT_RRDY)
num_bytes = dev->fifo_size;
- else
- num_bytes = omap_i2c_read_reg(dev,
- OMAP_I2C_BUFSTAT_REG);
+ else /* read RXSTAT on RDR interrupt */
+ num_bytes = (omap_i2c_read_reg(dev,
+ OMAP_I2C_BUFSTAT_REG)
+ >> 8) & 0x3F;
}
while (num_bytes) {
num_bytes--;
@@ -731,9 +745,10 @@ omap_i2c_isr(int this_irq, void *dev_id)
if (dev->fifo_size) {
if (stat & OMAP_I2C_STAT_XRDY)
num_bytes = dev->fifo_size;
- else
+ else /* read TXSTAT on XDR interrupt */
num_bytes = omap_i2c_read_reg(dev,
- OMAP_I2C_BUFSTAT_REG);
+ OMAP_I2C_BUFSTAT_REG)
+ & 0x3F;
}
while (num_bytes) {
num_bytes--;
@@ -760,6 +775,27 @@ omap_i2c_isr(int this_irq, void *dev_id)
"data to send\n");
break;
}
+
+ /*
+ * OMAP3430 Errata 1.153: When an XRDY/XDR
+ * is hit, wait for XUDF before writing data
+ * to DATA_REG. Otherwise some data bytes can
+ * be lost while transferring them from the
+ * memory to the I2C interface.
+ */
+
+ if (dev->rev <= OMAP_I2C_REV_ON_3430) {
+ while (!(stat & OMAP_I2C_STAT_XUDF)) {
+ if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
+ omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
+ err |= OMAP_I2C_STAT_XUDF;
+ goto complete;
+ }
+ cpu_relax();
+ stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+ }
+ }
+
omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
}
omap_i2c_ack_stat(dev,
@@ -879,7 +915,7 @@ omap_i2c_probe(struct platform_device *pdev)
i2c_set_adapdata(adap, dev);
adap->owner = THIS_MODULE;
adap->class = I2C_CLASS_HWMON;
- strncpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
+ strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
adap->algo = &omap_i2c_algo;
adap->dev.parent = &pdev->dev;