diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-stu300.c | 2 | ||||
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 17 | ||||
| -rw-r--r-- | drivers/i2c/i2c-core-base.c | 11 |
3 files changed, 19 insertions, 11 deletions
diff --git a/drivers/i2c/busses/i2c-stu300.c b/drivers/i2c/busses/i2c-stu300.c index e866c481bfc3..fce52bdab2b7 100644 --- a/drivers/i2c/busses/i2c-stu300.c +++ b/drivers/i2c/busses/i2c-stu300.c @@ -127,7 +127,7 @@ enum stu300_error { /* * The number of address send athemps tried before giving up. - * If the first one failes it seems like 5 to 8 attempts are required. + * If the first one fails it seems like 5 to 8 attempts are required. */ #define NUM_ADDR_RESEND_ATTEMPTS 12 diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 5fccd1f1bca8..797def5319f1 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -545,6 +545,14 @@ static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev *i2c_dev) { u32 cnfg; + /* + * NACK interrupt is generated before the I2C controller generates + * the STOP condition on the bus. So wait for 2 clock periods + * before disabling the controller so that the STOP condition has + * been delivered properly. + */ + udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate)); + cnfg = i2c_readl(i2c_dev, I2C_CNFG); if (cnfg & I2C_CNFG_PACKET_MODE_EN) i2c_writel(i2c_dev, cnfg & ~I2C_CNFG_PACKET_MODE_EN, I2C_CNFG); @@ -706,15 +714,6 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) return 0; - /* - * NACK interrupt is generated before the I2C controller generates - * the STOP condition on the bus. So wait for 2 clock periods - * before resetting the controller so that the STOP condition has - * been delivered properly. - */ - if (i2c_dev->msg_err == I2C_ERR_NO_ACK) - udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate)); - tegra_i2c_init(i2c_dev); if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { if (msg->flags & I2C_M_IGNORE_NAK) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 31d16ada6e7d..301285c54603 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -198,7 +198,16 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap) val = !val; bri->set_scl(adap, val); - ndelay(RECOVERY_NDELAY); + + /* + * If we can set SDA, we will always create STOP here to ensure + * the additional pulses will do no harm. This is achieved by + * letting SDA follow SCL half a cycle later. + */ + ndelay(RECOVERY_NDELAY / 2); + if (bri->set_sda) + bri->set_sda(adap, val); + ndelay(RECOVERY_NDELAY / 2); } /* check if recovery actually succeeded */ |