This is a note to let you know that I've just added the patch titled
spi: spi-fsl-lpspi: Adjust type of scldiv
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-spi-fsl-lpspi-adjust-type-of-scldiv.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 a4d06b125a0567bc27a75bb1ea8078c841dd3a87
Author: Stefan Wahren <wahrenst@xxxxxxx>
Date: Mon Sep 30 11:30:54 2024 +0200
spi: spi-fsl-lpspi: Adjust type of scldiv
[ Upstream commit fa8ecda9876ac1e7b29257aa82af1fd0695496e2 ]
The target value of scldiv is just a byte, but its calculation in
fsl_lpspi_set_bitrate could be negative. So use an adequate type to store
the result and avoid overflows. After that this needs range check
adjustments, but this should make the code less opaque.
Signed-off-by: Stefan Wahren <wahrenst@xxxxxxx>
Reviewed-by: Frank Li <Frank.Li@xxxxxxx>
Link: https://patch.msgid.link/20240930093056.93418-2-wahrenst@xxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index 514a2c5c84226..9e2541dee56e5 100644
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -315,9 +315,10 @@ static void fsl_lpspi_set_watermark(struct fsl_lpspi_data *fsl_lpspi)
static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi)
{
struct lpspi_config config = fsl_lpspi->config;
- unsigned int perclk_rate, scldiv, div;
+ unsigned int perclk_rate, div;
u8 prescale_max;
u8 prescale;
+ int scldiv;
perclk_rate = clk_get_rate(fsl_lpspi->clk_per);
prescale_max = fsl_lpspi->devtype_data->prescale_max;
@@ -338,13 +339,13 @@ static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi)
for (prescale = 0; prescale <= prescale_max; prescale++) {
scldiv = div / (1 << prescale) - 2;
- if (scldiv < 256) {
+ if (scldiv >= 0 && scldiv < 256) {
fsl_lpspi->config.prescale = prescale;
break;
}
}
- if (scldiv >= 256)
+ if (scldiv < 0 || scldiv >= 256)
return -EINVAL;
writel(scldiv | (scldiv << 8) | ((scldiv >> 1) << 16),
