Blackfin: spi-docs: further clarify GPIO CS behavior with various modes
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/Documentation/blackfin/bfin-spi-notes.txt b/Documentation/blackfin/bfin-spi-notes.txt
index 556fa87..eae6eaf 100644
--- a/Documentation/blackfin/bfin-spi-notes.txt
+++ b/Documentation/blackfin/bfin-spi-notes.txt
@@ -9,6 +9,8 @@
In most cases you can utilize SPI MODE_3 instead of MODE_0 to work-around this
behavior. If your SPI slave device in question requires SPI MODE_0 or MODE_2
timing, you can utilize the GPIO controlled SPI Slave Select option instead.
+In this case, you should use GPIO based CS for all of your slaves and not just
+the ones using mode 0 or 2 in order to guarantee correct CS toggling behavior.
You can even use the same pin whose peripheral role is a SSEL,
but use it as a GPIO instead.