WRRD, then the msgs pointer is incremented by 2. For all other operations, msgs is simply incremented by 1. Fixes: b2ed11e224a2 ("I2C: mediatek: Add driver for MediaTek MT8173 I2C controller") Signed-off-by: Leilk.Liu Suggested-by: Chen-Yu Tsai Reviewed-by: Chen-Yu Tsai Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-mt65xx.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index ab456c3717db1..dee40704825cb 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -1243,6 +1243,7 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap, { int ret; int left_num = num; + bool write_then_read_en = false; struct mtk_i2c *i2c = i2c_get_adapdata(adap); ret = clk_bulk_enable(I2C_MT65XX_CLK_MAX, i2c->clocks); @@ -1256,6 +1257,7 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap, if (!(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD) && msgs[0].addr == msgs[1].addr) { i2c->auto_restart = 0; + write_then_read_en = true; } } @@ -1280,12 +1282,10 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap, else i2c->op = I2C_MASTER_WR; - if (!i2c->auto_restart) { - if (num > 1) { - /* combined two messages into one transaction */ - i2c->op = I2C_MASTER_WRRD; - left_num--; - } + if (write_then_read_en) { + /* combined two messages into one transaction */ + i2c->op = I2C_MASTER_WRRD; + left_num--; } /* always use DMA mode. */ @@ -1293,7 +1293,10 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap, if (ret < 0) goto err_exit; - msgs++; + if (i2c->op == I2C_MASTER_WRRD) + msgs += 2; + else + msgs++; } /* the return value is number of executed messages */ ret = num; -- 2.51.0[PATCH 6.17 199/563] i2c: mediatek: fix potential incorrect use of I2C_MASTER_WRRDGreg Kroah-Hartman undefinedstable@vger.kernel.org undefined undefined undefined undefined undefined undefinedİgƒ˜o