Commit 42982d02 authored Jul 06, 2021 by Peter Hess Committed by Greg Kroah-Hartman Jul 28, 2021

spi: mediatek: fix fifo rx mode



[ Upstream commit 3a70dd2d050331ee4cf5ad9d5c0a32d83ead9a43 ]

In FIFO mode were two problems:
- RX mode was never handled and
- in this case the tx_buf pointer was NULL and caused an exception

fix this by handling RX mode in mtk_spi_fifo_transfer

Fixes: a568231f ("spi: mediatek: Add spi bus for Mediatek MT8173")
Signed-off-by: Peter Hess <peter.hess@ph-home.de>
Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
Link: https://lore.kernel.org/r/20210706121609.680534-1-linux@fw-web.de


Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 60d852e1

drivers/spi/spi-mt65xx.c

+13 −3

Original line number	Diff line number	Diff line
		@@ -338,14 +338,24 @@ static int mtk_spi_fifo_transfer(struct spi_master *master,
		mtk_spi_setup_packet(master);

		cnt = xfer->len / 4;
		if (xfer->tx_buf)
		iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);

		if (xfer->rx_buf)
		ioread32_rep(mdata->base + SPI_RX_DATA_REG, xfer->rx_buf, cnt);

		remainder = xfer->len % 4;
		if (remainder > 0) {
		reg_val = 0;
		if (xfer->tx_buf) {
		memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
		writel(reg_val, mdata->base + SPI_TX_DATA_REG);
		}
		if (xfer->rx_buf) {
		reg_val = readl(mdata->base + SPI_RX_DATA_REG);
		memcpy(xfer->rx_buf + (cnt * 4), &reg_val, remainder);
		}
		}

		mtk_spi_enable_transfer(master);