gpiolib: provide provision to register pin ranges
pinctrl subsystem needs gpio chip base to prepare set of gpio
pin ranges, which a given pinctrl driver can handle. This is
important to handle pinctrl gpio request calls in order to
program a given pin properly for gpio operation.
As gpio base is allocated dynamically during gpiochip
registration, presently there exists no clean way to pass this
information to the pinctrl subsystem.
After few discussions from [1], it was concluded that may be
gpio controller reporting the pin range it supports, is a
better way than pinctrl subsystem directly registering it.
[1] http://comments.gmane.org/gmane.linux.ports.arm.kernel/184816
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
[Edited documentation a bit]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt
index a1cd2f9..da40efb 100644
--- a/Documentation/pinctrl.txt
+++ b/Documentation/pinctrl.txt
@@ -364,6 +364,9 @@
the range ID value, so that the pin controller knows which range it should
deal with.
+Calling pinctrl_add_gpio_range from pinctrl driver is DEPRECATED. Please see
+section 2.1 of Documentation/devicetree/bindings/gpio/gpio.txt on how to bind
+pinctrl and gpio drivers.
PINMUX interfaces
=================