| From 6da4db862ccf6ee53d2cc0ea5831f85e6a256805 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 10 Sep 2018 11:54:21 +0800 |
| Subject: spi: mediatek: Don't modify spi_transfer when transfer. |
| |
| From: Peter Shih <pihsun@chromium.org> |
| |
| [ Upstream commit 00bca73bfca4fb0ab089b94cad0fc83d8b49c25f ] |
| |
| 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: Pi-Hsun Shih <pihsun@chromium.org> |
| |
| Change-Id: I23e218cd964f16c0b2b26127d4a5ca6529867673 |
| Signed-off-by: Mark Brown <broonie@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/spi/spi-mt65xx.c | 37 +++++++++++++++++++++---------------- |
| 1 file changed, 21 insertions(+), 16 deletions(-) |
| |
| diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c |
| index 86bf45667a040..3dc31627c6558 100644 |
| --- a/drivers/spi/spi-mt65xx.c |
| +++ b/drivers/spi/spi-mt65xx.c |
| @@ -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), |
| - ®_val, remainder); |
| + memcpy(trans->rx_buf + |
| + mdata->num_xfered + |
| + (cnt * 4), |
| + ®_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(®_val, trans->tx_buf + (cnt * 4), remainder); |
| + memcpy(®_val, |
| + trans->tx_buf + (cnt * 4) + mdata->num_xfered, |
| + remainder); |
| writel(reg_val, mdata->base + SPI_TX_DATA_REG); |
| } |
| |
| -- |
| 2.20.1 |
| |