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i2c: imx: Only DMA messages with I2C_M_DMA_SAFE flag set

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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: 4544b9f25e ("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>
This commit is contained in:
Andrew Lunn 2022-11-10 00:59:02 +01:00 committed by Wolfram Sang
parent 7d8ccf4f11
commit d36678f790
1 changed files with 4 additions and 2 deletions
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6
drivers/i2c/busses/i2c-imx.c
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@ -1132,7 +1132,8 @@ 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",
@ -1298,7 +1299,8 @@ 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);