Commit 8689b80b authored Aug 07, 2022 by Robin Reckmann Committed by Wolfram Sang Aug 11, 2022

i2c: qcom-geni: Fix GPI DMA buffer sync-back



Fix i2c transfers using GPI DMA mode for all message types that do not set
the I2C_M_DMA_SAFE flag (e.g. SMBus "read byte").

In this case a bounce buffer is returned by i2c_get_dma_safe_msg_buf(),
and it has to synced back to the message after the transfer is done.

Add missing assignment of dma buffer in geni_i2c_gpi().

Set xferred in i2c_put_dma_safe_msg_buf() to true in case of no error to
ensure the sync-back of this dma buffer to the message.

Fixes: d8703554 ("i2c: qcom-geni: Add support for GPI DMA")
Signed-off-by: Robin Reckmann <robin.reckmann@gmail.com>
Tested-by: Luca Weiss <luca.weiss@fairphone.com>
Tested-by: Caleb Connolly <caleb@connolly.tech>
Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

parent ffcf9c57

drivers/i2c/busses/i2c-qcom-geni.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -494,12 +494,12 @@ static void geni_i2c_gpi_unmap(struct geni_i2c_dev gi2c, struct i2c_msg msg,
		{
		if (tx_buf) {
		dma_unmap_single(gi2c->se.dev->parent, tx_addr, msg->len, DMA_TO_DEVICE);
		i2c_put_dma_safe_msg_buf(tx_buf, msg, false);
		i2c_put_dma_safe_msg_buf(tx_buf, msg, !gi2c->err);
		}

		if (rx_buf) {
		dma_unmap_single(gi2c->se.dev->parent, rx_addr, msg->len, DMA_FROM_DEVICE);
		i2c_put_dma_safe_msg_buf(rx_buf, msg, false);
		i2c_put_dma_safe_msg_buf(rx_buf, msg, !gi2c->err);
		}
		}

		@@ -563,6 +563,7 @@ static int geni_i2c_gpi(struct geni_i2c_dev gi2c, struct i2c_msg msg,
		desc->callback_param = gi2c;

		dmaengine_submit(desc);
		*buf = dma_buf;
		*dma_addr_p = addr;

		return 0;