From: Andrew Lunn andrew@lunn.ch
[ Upstream commit d36678f7905cbd1dc55a8a96e066dafd749d4600 ]
Recent changes to the DMA code has resulting in the IMX driver failing I2C transfers when the buffer has been vmalloc. Only perform DMA transfers if the message has the I2C_M_DMA_SAFE flag set, indicating the client is providing a buffer which is DMA safe.
This is a minimal fix for stable. The I2C core provides helpers to allocate a bounce buffer. For a fuller fix the master should make use of these helpers.
Fixes: 4544b9f25e70 ("dma-mapping: Add vmap checks to dma_map_single()") Signed-off-by: Andrew Lunn andrew@lunn.ch Acked-by: Oleksij Rempel o.rempel@pengutronix.de Signed-off-by: Wolfram Sang wsa@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i2c/busses/i2c-imx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index be4ad516293b..b4fb4336b4e8 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -843,7 +843,8 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, int i, result; unsigned int temp; int block_data = msgs->flags & I2C_M_RECV_LEN; - int use_dma = i2c_imx->dma && msgs->len >= DMA_THRESHOLD && !block_data; + int use_dma = i2c_imx->dma && msgs->flags & I2C_M_DMA_SAFE && + msgs->len >= DMA_THRESHOLD && !block_data;
dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n", @@ -1011,7 +1012,8 @@ static int i2c_imx_xfer_common(struct i2c_adapter *adapter, result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg, atomic); } else { if (!atomic && - i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD) + i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD && + msgs[i].flags & I2C_M_DMA_SAFE) result = i2c_imx_dma_write(i2c_imx, &msgs[i]); else result = i2c_imx_write(i2c_imx, &msgs[i], atomic);