pinctrl: qcom: handle reserved ranges
Some Qualcomm boards feature reserved ranges of pins which are protected
by firmware. Attempting to read or write any registers associated with
these pins results the board resetting.
Add support for parsing these ranges from devicetree and ensure that the
pinctrl and GPIO drivers don't try to interact with these pins.
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250410-topic-sm8x50-pinctrl-reserved-ranges-v2-1-654488392b9a@linaro.org
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
diff --git a/arch/arm/mach-snapdragon/include/mach/gpio.h b/arch/arm/mach-snapdragon/include/mach/gpio.h
index cc8f405..11e8104 100644
--- a/arch/arm/mach-snapdragon/include/mach/gpio.h
+++ b/arch/arm/mach-snapdragon/include/mach/gpio.h
@@ -46,4 +46,19 @@
return pindata->special_pins_start && pin >= pindata->special_pins_start;
}
+struct udevice;
+
+/**
+ * msm_pinctrl_is_reserved() - Check if a pin lies in a reserved range
+ *
+ * @dev: pinctrl device
+ * @pin: Pin number
+ *
+ * Returns: true if pin is reserved, otherwise false
+ *
+ * Call using dev_get_parent() from the GPIO device, it is a child of
+ * the pinctrl device.
+ */
+bool msm_pinctrl_is_reserved(struct udevice *dev, unsigned int pin);
+
#endif /* _QCOM_GPIO_H_ */