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-rw-r--r--Documentation/driver-api/pwm.rst11
1 files changed, 6 insertions, 5 deletions
diff --git a/Documentation/driver-api/pwm.rst b/Documentation/driver-api/pwm.rst
index 3c28ccc4b6..b41b1c5647 100644
--- a/Documentation/driver-api/pwm.rst
+++ b/Documentation/driver-api/pwm.rst
@@ -143,11 +143,12 @@ to implement the pwm_*() functions itself. This means that it's impossible
to have multiple PWM drivers in the system. For this reason it's mandatory
for new drivers to use the generic PWM framework.
-A new PWM controller/chip can be added using pwmchip_add() and removed
-again with pwmchip_remove(). pwmchip_add() takes a filled in struct
-pwm_chip as argument which provides a description of the PWM chip, the
-number of PWM devices provided by the chip and the chip-specific
-implementation of the supported PWM operations to the framework.
+A new PWM controller/chip can be allocated using pwmchip_alloc(), then
+registered using pwmchip_add() and removed again with pwmchip_remove(). To undo
+pwmchip_alloc() use pwmchip_put(). pwmchip_add() takes a filled in struct
+pwm_chip as argument which provides a description of the PWM chip, the number
+of PWM devices provided by the chip and the chip-specific implementation of the
+supported PWM operations to the framework.
When implementing polarity support in a PWM driver, make sure to respect the
signal conventions in the PWM framework. By definition, normal polarity