spi: Support transfer speed checking in the core
Allow drivers to avoid implementing their own checks for simple rates by
specifying the limits in the master structure.
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 28e440b..cdf6681 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -233,6 +233,8 @@
* suported. If set, the SPI core will reject any transfer with an
* unsupported bits_per_word. If not set, this value is simply ignored,
* and it's up to the individual driver to perform any validation.
+ * @min_speed_hz: Lowest supported transfer speed
+ * @max_speed_hz: Highest supported transfer speed
* @flags: other constraints relevant to this driver
* @bus_lock_spinlock: spinlock for SPI bus locking
* @bus_lock_mutex: mutex for SPI bus locking
@@ -312,6 +314,10 @@
#define SPI_BIT_MASK(bits) (((bits) == 32) ? ~0UL : (BIT(bits) - 1))
#define SPI_BPW_RANGE_MASK(min, max) (SPI_BIT_MASK(max) - SPI_BIT_MASK(min - 1))
+ /* limits on transfer speed */
+ u32 min_speed_hz;
+ u32 max_speed_hz;
+
/* other constraints relevant to this driver */
u16 flags;
#define SPI_MASTER_HALF_DUPLEX BIT(0) /* can't do full duplex */