spi: Use a 32-bit DT property for spi-cs-setup-delay-ns

65us is not a reasonable maximum for this property, as some devices
might need a much longer setup time (e.g. those driven by firmware on
the other end). Plus, device tree property values are in 32-bit cells
and smaller widths should not be used without good reason.

Also move the logic to a helper function, since this will later be used
to parse other CS delay properties too.

Fixes: 33a2fde5f77b ("spi: Introduce spi-cs-setup-ns property")
Signed-off-by: Janne Grunau <j@jannau.net>
Signed-off-by: Hector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20230113102309.18308-2-marcan@marcan.st
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 15f174f..3f33934 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2220,11 +2220,26 @@ void spi_flush_queue(struct spi_controller *ctlr)
 /*-------------------------------------------------------------------------*/
 
 #if defined(CONFIG_OF)
+static void of_spi_parse_dt_cs_delay(struct device_node *nc,
+                                    struct spi_delay *delay, const char *prop)
+{
+       u32 value;
+
+       if (!of_property_read_u32(nc, prop, &value)) {
+               if (value > U16_MAX) {
+                       delay->value = DIV_ROUND_UP(value, 1000);
+                       delay->unit = SPI_DELAY_UNIT_USECS;
+               } else {
+                       delay->value = value;
+                       delay->unit = SPI_DELAY_UNIT_NSECS;
+               }
+       }
+}
+
 static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
                           struct device_node *nc)
 {
        u32 value;
-       u16 cs_setup;
        int rc;
 
        /* Mode (clock phase/polarity/etc.) */
@@ -2310,10 +2325,8 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
        if (!of_property_read_u32(nc, "spi-max-frequency", &value))
                spi->max_speed_hz = value;
 
-       if (!of_property_read_u16(nc, "spi-cs-setup-delay-ns", &cs_setup)) {
-               spi->cs_setup.value = cs_setup;
-               spi->cs_setup.unit = SPI_DELAY_UNIT_NSECS;
-       }
+       /* Device CS delays */
+       of_spi_parse_dt_cs_delay(nc, &spi->cs_setup, "spi-cs-setup-delay-ns");
 
        return 0;
 }