dm: spi: Avoid setting the speed with every transfer
Only set the speed if it has changed from last time. Since the speed will
be 0 when the device is probed it will always be changed on the first
transfer after the device is probed.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/spi/spi-uclass.c b/drivers/spi/spi-uclass.c
index 83fe8e0..737ae64 100644
--- a/drivers/spi/spi-uclass.c
+++ b/drivers/spi/spi-uclass.c
@@ -63,9 +63,12 @@
}
if (!speed)
speed = 100000;
- ret = spi_set_speed_mode(bus, speed, slave->mode);
- if (ret)
- return ret;
+ if (speed != slave->speed) {
+ ret = spi_set_speed_mode(bus, speed, slave->mode);
+ if (ret)
+ return ret;
+ slave->speed = speed;
+ }
return ops->claim_bus ? ops->claim_bus(dev) : 0;
}
diff --git a/include/spi.h b/include/spi.h
index 9495ca5..3f198f8 100644
--- a/include/spi.h
+++ b/include/spi.h
@@ -100,6 +100,8 @@
* @dev: SPI slave device
* @max_hz: Maximum speed for this slave
* @mode: SPI mode to use for this slave (see SPI mode flags)
+ * @speed: Current bus speed. This is 0 until the bus is first
+ * claimed.
* @bus: ID of the bus that the slave is attached to. For
* driver model this is the sequence number of the SPI
* bus (bus->seq) so does not need to be stored
@@ -117,6 +119,7 @@
#ifdef CONFIG_DM_SPI
struct udevice *dev; /* struct spi_slave is dev->parentdata */
uint max_hz;
+ uint speed;
uint mode;
#else
unsigned int bus;