By working with external hardware ECC engines, we figured out that Under certain circumstances, it is needed for the SPI controller to check INT_TX_EMPTY and INT_RX_NOT_EMPTY in both receive and transmit path (not only in the receive path). The delay penalty being negligible, move this code in the common path.

Fixes: b942d80b0a39 ("spi: Add MXIC controller driver") Cc: stable@vger.kernel.org Suggested-by: Mason Yang masonccyang@mxic.com.tw Signed-off-by: Miquel Raynal miquel.raynal@bootlin.com

---

drivers/spi/spi-mxic.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/drivers/spi/spi-mxic.c b/drivers/spi/spi-mxic.c index 96b418293bf2..4fb19e6f94b0 100644 --- a/drivers/spi/spi-mxic.c +++ b/drivers/spi/spi-mxic.c @@ -304,25 +304,21 @@ static int mxic_spi_data_xfer(struct mxic_spi *mxic, const void *txbuf,

   writel(data, mxic->regs + TXD(nbytes % 4));

•  ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
  

•            sts & INT_TX_EMPTY, 0, USEC_PER_SEC);
  

•  if (ret)
  

•     return ret;
  

•  ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
  

•            sts & INT_RX_NOT_EMPTY, 0,
  

•            USEC_PER_SEC);
  

•  if (ret)
  

•     return ret;
  

•  data = readl(mxic->regs + RXD);
   if (rxbuf) {
  

•     ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
  

•               sts & INT_TX_EMPTY, 0,
  

•               USEC_PER_SEC);
  

•     if (ret)
  

•        return ret;
  

•     ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
  

•               sts & INT_RX_NOT_EMPTY, 0,
  

•               USEC_PER_SEC);
  

•     if (ret)
  

•        return ret;
  

•     data = readl(mxic->regs + RXD);
      data >>= (8 * (4 - nbytes));
      memcpy(rxbuf + pos, &data, nbytes);
  

•     WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY);
  

•  } else {
  

•     readl(mxic->regs + RXD);
   }
   WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY);
  
  

-- 2.27.0

Reviewed-by: Zhengxun Li zhengxunli@mxic.com.tw

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