diff options
| author |   Masahiro Yamada <yamada.masahiro@socionext.com> | 2018-08-31 23:30:47 +0900 |
|---|---|---|
| committer |   Wolfram Sang <wsa@the-dreams.de> | 2018-09-02 23:50:43 +0200 |
| commit | 38f5d8d8cbb2ffa2b54315118185332329ec891c (patch) | |
| tree | d62d120f08f9cae3d7357d450fcd5b55b5e27da9 | |
| parent | Linux 4.19-rc2 (diff) | |
| download | linux-dev-38f5d8d8cbb2ffa2b54315118185332329ec891c.tar.xz linux-dev-38f5d8d8cbb2ffa2b54315118185332329ec891c.zip | |
i2c: uniphier: issue STOP only for last message or I2C_M_STOP
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: dd6fd4a32793 ("i2c: uniphier: add UniPhier FIFO-less I2C driver")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| -rw-r--r-- | drivers/i2c/busses/i2c-uniphier.c | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/drivers/i2c/busses/i2c-uniphier.c b/drivers/i2c/busses/i2c-uniphier.c index bb181b088291..454f914ae66d 100644 --- a/drivers/i2c/busses/i2c-uniphier.c +++ b/drivers/i2c/busses/i2c-uniphier.c @@ -248,11 +248,8 @@ static int uniphier_i2c_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_i2c_master_xfer_one(adap, msg, stop); if (ret) |