6.6-stable review patch. If anyone has any objections, please let me know.
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From: Stefan Wahren wahrenst@gmx.net
[ Upstream commit af357a6a3b7d685e7aa621c6fb1d4ed6c349ec9e ]
Currently the driver is not able to handle the case that a SPI device specifies a higher spi-max-frequency than half of per-clk:
per-clk should be at least two times of transfer speed
Fix this by clamping to the max possible value and use the minimum SCK period of 2 cycles.
Fixes: 77736a98b859 ("spi: lpspi: add the error info of transfer speed setting") Signed-off-by: Stefan Wahren wahrenst@gmx.net Link: https://patch.msgid.link/20250807100742.9917-1-wahrenst@gmx.net Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-fsl-lpspi.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c index 9e2541dee56e..fa899ab2014c 100644 --- a/drivers/spi/spi-fsl-lpspi.c +++ b/drivers/spi/spi-fsl-lpspi.c @@ -330,13 +330,11 @@ static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi) }
if (config.speed_hz > perclk_rate / 2) { - dev_err(fsl_lpspi->dev, - "per-clk should be at least two times of transfer speed"); - return -EINVAL; + div = 2; + } else { + div = DIV_ROUND_UP(perclk_rate, config.speed_hz); }
- div = DIV_ROUND_UP(perclk_rate, config.speed_hz); - for (prescale = 0; prescale <= prescale_max; prescale++) { scldiv = div / (1 << prescale) - 2; if (scldiv >= 0 && scldiv < 256) {