pinctrl: Add help text to Kconfig
The pinctrl Kconfig options should have help messages. Add this to a few
options.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 30b8e45..918a859 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -47,7 +47,10 @@
default y
help
This option enables pin multiplexing through the generic pinctrl
- framework.
+ framework. Most SoCs have their own own multiplexing arrangement
+ where a single pin can be used for several functions. An SoC pinctrl
+ driver allows the required function to be selected for each pin.
+ The driver is typically controlled by the device tree.
config PINCONF
bool "Support pin configuration controllers"
@@ -86,6 +89,12 @@
help
This option is an SPL-variant of the PINMUX option.
See the help of PINMUX for details.
+ The pinctrl subsystem can add a substantial overhead to the SPL
+ image since it typically requires quite a few tables either in the
+ driver or in the device tree. If this is acceptable and you need
+ to adjust pin multiplexing in SPL in order to boot into U-Boot,
+ enable this option. You will need to enable device tree in SPL
+ for this to work.
config SPL_PINCONF
bool "Support pin configuration controllers in SPL"