Unverified Commit 00bca73b authored by Peter Shih's avatar Peter Shih Committed by Mark Brown
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spi: mediatek: Don't modify spi_transfer when transfer. 



Mediatek SPI driver modifies some fields (tx_buf, rx_buf, len, tx_dma,
rx_dma) of the spi_transfer* passed in when doing transfer_one and in
interrupt handler. This is somewhat unexpected, and there are some
caller (e.g. Cr50 spi driver) that reuse the spi_transfer for multiple
messages. Add a field to record how many bytes have been transferred,
and calculate the right len / buffer based on it instead.

Signed-off-by: default avatarPi-Hsun Shih <pihsun@chromium.org>

Change-Id: I23e218cd964f16c0b2b26127d4a5ca6529867673
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 0fd85869

drivers/spi/spi-mt65xx.c

+21 −16
Original line number Diff line number Diff line
@@ -98,6 +98,7 @@ struct mtk_spi { 
	struct clk *parent_clk, *sel_clk, *spi_clk;

	struct spi_transfer *cur_transfer;

	u32 xfer_len;

	u32 num_xfered;

	struct scatterlist *tx_sgl, *rx_sgl;

	u32 tx_sgl_len, rx_sgl_len;

	const struct mtk_spi_compatible *dev_comp;
@@ -385,6 +386,7 @@ static int mtk_spi_fifo_transfer(struct spi_master *master, 


	mdata->cur_transfer = xfer;

	mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, xfer->len);

	mdata->num_xfered = 0;

	mtk_spi_prepare_transfer(master, xfer);

	mtk_spi_setup_packet(master);
@@ -415,6 +417,7 @@ static int mtk_spi_dma_transfer(struct spi_master *master, 
	mdata->tx_sgl_len = 0;

	mdata->rx_sgl_len = 0;

	mdata->cur_transfer = xfer;

	mdata->num_xfered = 0;



	mtk_spi_prepare_transfer(master, xfer);
@@ -482,7 +485,7 @@ static int mtk_spi_setup(struct spi_device *spi) 


static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)

{

	u32 cmd, reg_val, cnt, remainder;

	u32 cmd, reg_val, cnt, remainder, len;

	struct spi_master *master = dev_id;

	struct mtk_spi *mdata = spi_master_get_devdata(master);

	struct spi_transfer *trans = mdata->cur_transfer;
@@ -497,36 +500,38 @@ static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id) 
		if (trans->rx_buf) {

			cnt = mdata->xfer_len / 4;

			ioread32_rep(mdata->base + SPI_RX_DATA_REG,

				     trans->rx_buf, cnt);

				     trans->rx_buf + mdata->num_xfered, cnt);

			remainder = mdata->xfer_len % 4;

			if (remainder > 0) {

				reg_val = readl(mdata->base + SPI_RX_DATA_REG);

				memcpy(trans->rx_buf + (cnt * 4),

					&reg_val, remainder);

				memcpy(trans->rx_buf +

					mdata->num_xfered +

					(cnt * 4),

					&reg_val,

					remainder);

			}

		}



		trans->len -= mdata->xfer_len;

		if (!trans->len) {

		mdata->num_xfered += mdata->xfer_len;

		if (mdata->num_xfered == trans->len) {

			spi_finalize_current_transfer(master);

			return IRQ_HANDLED;

		}



		if (trans->tx_buf)

			trans->tx_buf += mdata->xfer_len;

		if (trans->rx_buf)

			trans->rx_buf += mdata->xfer_len;



		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, trans->len);

		len = trans->len - mdata->num_xfered;

		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len);

		mtk_spi_setup_packet(master);



		cnt = trans->len / 4;

		iowrite32_rep(mdata->base + SPI_TX_DATA_REG, trans->tx_buf, cnt);

		cnt = len / 4;

		iowrite32_rep(mdata->base + SPI_TX_DATA_REG,

				trans->tx_buf + mdata->num_xfered, cnt);



		remainder = trans->len % 4;

		remainder = len % 4;

		if (remainder > 0) {

			reg_val = 0;

			memcpy(&reg_val, trans->tx_buf + (cnt * 4), remainder);

			memcpy(&reg_val,

				trans->tx_buf + (cnt * 4) + mdata->num_xfered,

				remainder);

			writel(reg_val, mdata->base + SPI_TX_DATA_REG);

		}

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