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authorLinus Torvalds <torvalds@linux-foundation.org>2018-07-14 01:34:29 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2018-07-14 01:34:29 +0300
commit2db39a2f491a48ec740e0214a7dd584eefc2137d (patch)
tree02bb3727ae2442d0146558cfd02b231783b767d1
parent3951dbf232e8500bef27f77437fd5d04b67cc6d1 (diff)
parentabe41184abac487264a4904bfcff2d5500dccce6 (diff)
downloadlinux-2db39a2f491a48ec740e0214a7dd584eefc2137d.tar.xz
Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang: - I2C core bugfix regarding bus recovery - driver bugfix for the tegra driver - typo correction * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: recovery: if possible send STOP with recovery pulses i2c: tegra: Fix NACK error handling i2c: stu300: use non-archaic spelling of failes
-rw-r--r--drivers/i2c/busses/i2c-stu300.c2
-rw-r--r--drivers/i2c/busses/i2c-tegra.c17
-rw-r--r--drivers/i2c/i2c-core-base.c11
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 */