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 <pihsun@chromium.org>

Change-Id: I23e218cd964f16c0b2b26127d4a5ca6529867673
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Peter Shih 2018-09-10 11:54:21 +08:00 committed by Mark Brown
parent 0fd85869c2
commit 00bca73bfc
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
1 changed files with 21 additions and 16 deletions

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@ -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);
}