From 00bca73bfca4fb0ab089b94cad0fc83d8b49c25f Mon Sep 17 00:00:00 2001 From: Peter Shih Date: Mon, 10 Sep 2018 11:54:21 +0800 Subject: [PATCH] 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: Pi-Hsun Shih Change-Id: I23e218cd964f16c0b2b26127d4a5ca6529867673 Signed-off-by: Mark Brown --- 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 86bf45667a04..3dc31627c655 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); }