doc: release notes: Update contents for 2.2
List the added PWM API flags parameter under changes to stable APIs
for the 2.2 release.
Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>
diff --git a/doc/releases/release-notes-2.2.rst b/doc/releases/release-notes-2.2.rst
index 7b4f2d2..4e09fc8 100644
--- a/doc/releases/release-notes-2.2.rst
+++ b/doc/releases/release-notes-2.2.rst
@@ -27,6 +27,19 @@
Stable API changes in this release
==================================
+* PWM
+
+ * The pwm_pin_set_cycles(), pwm_pin_set_usec(), and
+ pwm_pin_set_nsec() functions now take a flags parameter. The newly
+ introduced flags are PWM_POLARITY_NORMAL and PWM_POLARITY_INVERTED
+ for specifying the polarity of the PWM signal. The flags parameter
+ can be set to 0 if no flags are required (the default is
+ PWM_POLARITY_NORMAL).
+ * Similarly, the pwm_pin_set_t PWM driver API function function now
+ takes a flags parameter. The PWM controller driver must check the
+ value of the flags parameter and return -ENOTSUP if any
+ unsupported flag is set.
+
* USB
* The usb_enable() function, which was previously invoked automatically
