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spi: imx: fix the burst length at DMA mode and CPU mode 

For DMA mode, the bus width of the DMA is equal to the size of data
word, so burst length should be configured as bits per word.

For CPU mode, because of the spi transfer len is in byte, so calculate
the total number of words according to spi transfer len and bits per
word, burst length should be configured as total data bits.

Signed-off-by: Carlos Song <carlos.song@nxp.com>
Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
Fixes: e9b220aeac ("spi: spi-imx: correctly configure burst length when using dma")
Fixes: 5f66db08cb ("spi: imx: Take in account bits per word instead of assuming 8-bits")
Link: https://lore.kernel.org/r/20240204091912.36488-1-carlos.song@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Carlos Song 2024-02-04 17:19:12 +08:00 committed by Mark Brown
parent 6500ad28fd
commit c712c05e46
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GPG Key ID: 24D68B725D5487D0
1 changed files with 5 additions and 4 deletions
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9
drivers/spi/spi-imx.c
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@ -2,6 +2,7 @@
// Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
// Copyright (C) 2008 Juergen Beisert
#include <linux/bits.h>
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
@ -660,15 +661,15 @@ static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
<< MX51_ECSPI_CTRL_BL_OFFSET;
else {
if (spi_imx->usedma) {
ctrl |= (spi_imx->bits_per_word *
spi_imx_bytes_per_word(spi_imx->bits_per_word) - 1)
ctrl |= (spi_imx->bits_per_word - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
} else {
if (spi_imx->count >= MX51_ECSPI_CTRL_MAX_BURST)
ctrl |= (MX51_ECSPI_CTRL_MAX_BURST - 1)
ctrl |= (MX51_ECSPI_CTRL_MAX_BURST * BITS_PER_BYTE - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
else
ctrl |= (spi_imx->count * spi_imx->bits_per_word - 1)
ctrl |= spi_imx->count / DIV_ROUND_UP(spi_imx->bits_per_word,
BITS_PER_BYTE) * spi_imx->bits_per_word
<< MX51_ECSPI_CTRL_BL_OFFSET;
}
}