diff options
| author | Masahiro Yamada <yamada.masahiro@socionext.com> | 2018-08-31 23:30:48 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-10 08:52:11 +0200 |
| commit | 293c9b05879be53b17f80985123d93537264a875 (patch) | |
| tree | a10b76614a5d21e784bfe68b1cf9cb92a25430b4 | |
| parent | 3a20876cd27dc80c3aec27e161e3cfb20ca57d74 (diff) | |
i2c: uniphier-f: issue STOP only for last message or I2C_M_STOP
[ Upstream commit 4c85609b08c4761eca0a40fd7beb06bc650f252d ]
This driver currently emits a STOP if the next message is not
I2C_MD_RD. It should not do it because it disturbs the I2C_RDWR
ioctl, where read/write transactions are combined without STOP
between.
Issue STOP only when the message is the last one _or_ flagged with
I2C_M_STOP.
Fixes: 6a62974b667f ("i2c: uniphier_f: add UniPhier FIFO-builtin I2C driver")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/i2c/busses/i2c-uniphier-f.c | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c index e8d03bcfe3e0..3f6b43fe4d5d 100644 --- a/drivers/i2c/busses/i2c-uniphier-f.c +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -394,11 +394,8 @@ static int uniphier_fi2c_master_xfer(struct i2c_adapter *adap, return ret; for (msg = msgs; msg < emsg; msg++) { - /* If next message is read, skip the stop condition */ - bool stop = !(msg + 1 < emsg && msg[1].flags & I2C_M_RD); - /* but, force it if I2C_M_STOP is set */ - if (msg->flags & I2C_M_STOP) - stop = true; + /* Emit STOP if it is the last message or I2C_M_STOP is set. */ + bool stop = (msg + 1 == emsg) || (msg->flags & I2C_M_STOP); ret = uniphier_fi2c_master_xfer_one(adap, msg, stop); if (ret) |