diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-omap.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-omap.c | 54 |
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; |