Unverified Commit f276aacf authored by Janne Grunau's avatar Janne Grunau Committed by Mark Brown
Browse files

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: 33a2fde5 ("spi: Introduce spi-cs-setup-ns property")
Signed-off-by: default avatarJanne Grunau <j@jannau.net>
Signed-off-by: default avatarHector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20230113102309.18308-2-marcan@marcan.st


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent e0fe6a31

drivers/spi/spi.c

+18 −5
Original line number Diff line number Diff line
@@ -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;

}