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spi: mxic: Fix the transmit path

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commit 5fd6739e0df7e320bcac103dfb95fe75941fea17 upstream.

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>
Reviewed-by: Zhengxun Li <zhengxunli@mxic.com.tw>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20220127091808.1043392-10-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Miquel Raynal 2022-01-27 10:18:04 +01:00 committed by Greg Kroah-Hartman
parent e05221d201
commit 00a856fa69
1 changed files with 12 additions and 16 deletions
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28
drivers/spi/spi-mxic.c
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@ -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);