On 05.04.2022 12:38, Michael Walle wrote: > Am 2022-04-05 11:23, schrieb Codrin.Ciubotariu@xxxxxxxxxxxxx: >>> + if (dev->use_dma) { >>> + dma_buf = i2c_get_dma_safe_msg_buf(m_start, 1); >> >> If you want, you could just dev->buf = i2c_get_dma_safe... > > But where is the error handling in that case? dev->buf will > be NULL, which is eventually passed to dma_map_single(). > > Also, I need the dma_buf for the i2c_put_dma_safe_msg_buf() > call anyway, because dev->buf will be modified during > processing. You still: if (!dev->buf) { ret = -ENOMEM; goto out; } So, at91_do_twi_transfer()/dma_map_single() will not be called. Best regards, Codrin