[PATCH 08/13] spi: spi-fsl-lpspi: Make prescale erratum a bool

From: James Clark
Date: Thu Aug 14 2025 - 12:13:32 EST


This erratum only ever results in a max value of 1, otherwise the full 3
bits are available. To avoid repeating the same prescale values for
every new device's devdata, make it a bool.

Signed-off-by: James Clark <james.clark@xxxxxxxxxx>
---
drivers/spi/spi-fsl-lpspi.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index 332a852b746f..1013d5c994e9 100644
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -96,7 +96,7 @@ static const char * const pincfgs[] = {
};

struct fsl_lpspi_devtype_data {
- u8 prescale_max;
+ bool prescale_err : 1;
};

struct lpspi_config {
@@ -144,13 +144,16 @@ struct fsl_lpspi_data {
/*
* ERR051608 fixed or not:
* https://www.nxp.com/docs/en/errata/i.MX93_1P87f.pdf
+ *
+ * Devices with ERR051608 have a max TCR_PRESCALE value of 1, otherwise the full
+ * 3 bits are available (0-7).
*/
static const struct fsl_lpspi_devtype_data imx93_lpspi_devtype_data = {
- .prescale_max = 1,
+ .prescale_err = true,
};

static const struct fsl_lpspi_devtype_data imx7ulp_lpspi_devtype_data = {
- .prescale_max = 7,
+ .prescale_err = false,
};

static const struct of_device_id fsl_lpspi_dt_ids[] = {
@@ -329,12 +332,11 @@ static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi)
{
struct lpspi_config config = fsl_lpspi->config;
unsigned int perclk_rate, div;
- u8 prescale_max;
+ u8 prescale_max = fsl_lpspi->devtype_data->prescale_err ? 1 : 7;
u8 prescale;
int scldiv;

perclk_rate = clk_get_rate(fsl_lpspi->clk_per);
- prescale_max = fsl_lpspi->devtype_data->prescale_max;

if (!config.speed_hz) {
dev_err(fsl_lpspi->dev,

--
2.34.1