Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 5.15 485/667] i2c: at91: use dma safe buffers | Date | Tue, 7 Jun 2022 19:02:30 +0200 |
| |
From: Michael Walle <michael@walle.cc>
[ Upstream commit 03fbb903c8bf7e53e101e8d9a7b261264317c411 ]
The supplied buffer might be on the stack and we get the following error message: [ 3.312058] at91_i2c e0070600.i2c: rejecting DMA map of vmalloc memory
Use i2c_{get,put}_dma_safe_msg_buf() to get a DMA-able memory region if necessary.
Fixes: 60937b2cdbf9 ("i2c: at91: add dma support") Signed-off-by: Michael Walle <michael@walle.cc> Reviewed-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/i2c/busses/i2c-at91-master.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c index b0eae94909f4..5eca3b3bb609 100644 --- a/drivers/i2c/busses/i2c-at91-master.c +++ b/drivers/i2c/busses/i2c-at91-master.c @@ -656,6 +656,7 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num) unsigned int_addr_flag = 0; struct i2c_msg *m_start = msg; bool is_read; + u8 *dma_buf; dev_dbg(&adap->dev, "at91_xfer: processing %d messages:\n", num); @@ -703,7 +704,17 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num) dev->msg = m_start; dev->recv_len_abort = false; + if (dev->use_dma) { + dma_buf = i2c_get_dma_safe_msg_buf(m_start, 1); + if (!dma_buf) { + ret = -ENOMEM; + goto out; + } + dev->buf = dma_buf; + } + ret = at91_do_twi_transfer(dev); + i2c_put_dma_safe_msg_buf(dma_buf, m_start, !ret); ret = (ret < 0) ? ret : num; out: -- 2.35.1
| |