spi: add spi_set_speed func
This func helps mmc_spi driver set correct speed for mmc/sd, as
mmc card needs 400KHz clock for spi mode initialization.
Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/include/spi.h b/include/spi.h
index 320e50e..7887d0f9 100644
--- a/include/spi.h
+++ b/include/spi.h
@@ -176,6 +176,14 @@
void spi_cs_deactivate(struct spi_slave *slave);
/*-----------------------------------------------------------------------
+ * Set transfer speed.
+ * This sets a new speed to be applied for next spi_xfer().
+ * slave: The SPI slave
+ * hz: The transfer speed
+ */
+void spi_set_speed(struct spi_slave *slave, uint hz);
+
+/*-----------------------------------------------------------------------
* Write 8 bits, then read 8 bits.
* slave: The SPI slave we're communicating with
* byte: Byte to be written