Patch "spi: imx: fix the burst length at DMA mode and CPU mode" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

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

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     spi-imx-fix-the-burst-length-at-dma-mode-and-cpu-mod.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit e780ecb063493c40e80df63bdf21addcfa03864c
Author: Carlos Song <carlos.song@xxxxxxx>
Date:   Sun Feb 4 17:19:12 2024 +0800

    spi: imx: fix the burst length at DMA mode and CPU mode
    
    [ Upstream commit c712c05e46c8ce550842951e9e2606e24dbf0475 ]
    
    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@xxxxxxx>
    Reviewed-by: Clark Wang <xiaoning.wang@xxxxxxx>
    Fixes: e9b220aeacf1 ("spi: spi-imx: correctly configure burst length when using dma")
    Fixes: 5f66db08cbd3 ("spi: imx: Take in account bits per word instead of assuming 8-bits")
    Link: https://lore.kernel.org/r/20240204091912.36488-1-carlos.song@xxxxxxx
    Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 272bc871a848..e2d3e3ec1378 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -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;
 		}
 	}