From 4c85609b08c4761eca0a40fd7beb06bc650f252d Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 31 Aug 2018 23:30:48 +0900 Subject: [PATCH] i2c: uniphier-f: 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: 6a62974b667f ("i2c: uniphier_f: add UniPhier FIFO-builtin I2C driver") Signed-off-by: Masahiro Yamada Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-uniphier-f.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c index 9918bdd..a403e85 100644 --- a/drivers/i2c/busses/i2c-uniphier-f.c +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -401,11 +401,8 @@ 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) -- 2.7.4