firmware: arm_scmi: Add basic support for SCMI v3.2 pincontrol protocol

Add basic implementation of the SCMI v3.2 pincontrol protocol.

Co-developed-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com>
Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com>
Co-developed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20240418-pinctrl-scmi-v11-3-499dca9864a7@nxp.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

drivers/firmware/arm_scmi/Makefile

@@ -10,7 +10,8 @@ scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
-scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o
+scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o
+scmi-protocols-y += pinctrl.o
 scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
 
 obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o

drivers/firmware/arm_scmi/driver.c

@@ -3334,6 +3334,7 @@ static int __init scmi_driver_init(void)
 	scmi_voltage_register();
 	scmi_system_register();
 	scmi_powercap_register();
+	scmi_pinctrl_register();
 
 	return platform_driver_register(&scmi_driver);
 }
@@ -3351,6 +3352,7 @@ static void __exit scmi_driver_exit(void)
 	scmi_voltage_unregister();
 	scmi_system_unregister();
 	scmi_powercap_unregister();
+	scmi_pinctrl_unregister();
 
 	scmi_transports_exit();
 

drivers/firmware/arm_scmi/protocols.h

@@ -370,6 +370,7 @@ void __exit scmi_##name##_unregister(void)			\
 DECLARE_SCMI_REGISTER_UNREGISTER(base);
 DECLARE_SCMI_REGISTER_UNREGISTER(clock);
 DECLARE_SCMI_REGISTER_UNREGISTER(perf);
+DECLARE_SCMI_REGISTER_UNREGISTER(pinctrl);
 DECLARE_SCMI_REGISTER_UNREGISTER(power);
 DECLARE_SCMI_REGISTER_UNREGISTER(reset);
 DECLARE_SCMI_REGISTER_UNREGISTER(sensors);

include/linux/scmi_protocol.h

@@ -737,6 +737,89 @@ struct scmi_powercap_proto_ops {
 					  u32 *power_thresh_high);
 };
 
+enum scmi_pinctrl_selector_type {
+	PIN_TYPE = 0,
+	GROUP_TYPE,
+	FUNCTION_TYPE,
+};
+
+enum scmi_pinctrl_conf_type {
+	SCMI_PIN_DEFAULT = 0,
+	SCMI_PIN_BIAS_BUS_HOLD = 1,
+	SCMI_PIN_BIAS_DISABLE = 2,
+	SCMI_PIN_BIAS_HIGH_IMPEDANCE = 3,
+	SCMI_PIN_BIAS_PULL_UP = 4,
+	SCMI_PIN_BIAS_PULL_DEFAULT = 5,
+	SCMI_PIN_BIAS_PULL_DOWN = 6,
+	SCMI_PIN_DRIVE_OPEN_DRAIN = 7,
+	SCMI_PIN_DRIVE_OPEN_SOURCE = 8,
+	SCMI_PIN_DRIVE_PUSH_PULL = 9,
+	SCMI_PIN_DRIVE_STRENGTH = 10,
+	SCMI_PIN_INPUT_DEBOUNCE = 11,
+	SCMI_PIN_INPUT_MODE = 12,
+	SCMI_PIN_PULL_MODE = 13,
+	SCMI_PIN_INPUT_VALUE = 14,
+	SCMI_PIN_INPUT_SCHMITT = 15,
+	SCMI_PIN_LOW_POWER_MODE = 16,
+	SCMI_PIN_OUTPUT_MODE = 17,
+	SCMI_PIN_OUTPUT_VALUE = 18,
+	SCMI_PIN_POWER_SOURCE = 19,
+	SCMI_PIN_SLEW_RATE = 20,
+	SCMI_PIN_OEM_START = 192,
+	SCMI_PIN_OEM_END = 255,
+};
+
+/**
+ * struct scmi_pinctrl_proto_ops - represents the various operations provided
+ * by SCMI Pinctrl Protocol
+ *
+ * @count_get: returns count of the registered elements in given type
+ * @name_get: returns name by index of given type
+ * @group_pins_get: returns the set of pins, assigned to the specified group
+ * @function_groups_get: returns the set of groups, assigned to the specified
+ *	function
+ * @mux_set: set muxing function for groups of pins
+ * @settings_get_one: returns one configuration parameter for pin or group
+ *	specified by config_type
+ * @settings_get_all: returns all configuration parameters for pin or group
+ * @settings_conf: sets the configuration parameter for pin or group
+ * @pin_request: aquire pin before selecting mux setting
+ * @pin_free: frees pin, acquired by request_pin call
+ */
+struct scmi_pinctrl_proto_ops {
+	int (*count_get)(const struct scmi_protocol_handle *ph,
+			 enum scmi_pinctrl_selector_type type);
+	int (*name_get)(const struct scmi_protocol_handle *ph, u32 selector,
+			enum scmi_pinctrl_selector_type type,
+			const char **name);
+	int (*group_pins_get)(const struct scmi_protocol_handle *ph,
+			      u32 selector, const unsigned int **pins,
+			      unsigned int *nr_pins);
+	int (*function_groups_get)(const struct scmi_protocol_handle *ph,
+				   u32 selector, unsigned int *nr_groups,
+				   const unsigned int **groups);
+	int (*mux_set)(const struct scmi_protocol_handle *ph, u32 selector,
+		       u32 group);
+	int (*settings_get_one)(const struct scmi_protocol_handle *ph,
+				u32 selector,
+				enum scmi_pinctrl_selector_type type,
+				enum scmi_pinctrl_conf_type config_type,
+				u32 *config_value);
+	int (*settings_get_all)(const struct scmi_protocol_handle *ph,
+				u32 selector,
+				enum scmi_pinctrl_selector_type type,
+				unsigned int *nr_configs,
+				enum scmi_pinctrl_conf_type *config_types,
+				u32 *config_values);
+	int (*settings_conf)(const struct scmi_protocol_handle *ph,
+			     u32 selector, enum scmi_pinctrl_selector_type type,
+			     unsigned int nr_configs,
+			     enum scmi_pinctrl_conf_type *config_type,
+			     u32 *config_value);
+	int (*pin_request)(const struct scmi_protocol_handle *ph, u32 pin);
+	int (*pin_free)(const struct scmi_protocol_handle *ph, u32 pin);
+};
+
 /**
  * struct scmi_notify_ops  - represents notifications' operations provided by
  * SCMI core
@@ -842,6 +925,7 @@ enum scmi_std_protocol {
 	SCMI_PROTOCOL_RESET = 0x16,
 	SCMI_PROTOCOL_VOLTAGE = 0x17,
 	SCMI_PROTOCOL_POWERCAP = 0x18,
+	SCMI_PROTOCOL_PINCTRL = 0x19,
 };
 
 enum scmi_system_events {