Commit 5ad3d1cf authored by Cristian Marussi's avatar Cristian Marussi Committed by Sudeep Holla
Browse files

firmware: arm_scmi: Introduce new devres notification ops 

Expose to the SCMI drivers a new alternative devres managed notifications
API based on protocol handles.

All drivers still keep using the old API, no functional change.

Link: https://lore.kernel.org/r/20210316124903.35011-6-cristian.marussi@arm.com


Tested-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
parent 3dd2c814

drivers/firmware/arm_scmi/notify.c

+127 −2
Original line number Diff line number Diff line
@@ -1317,7 +1317,7 @@ static int scmi_event_handler_enable_events(struct scmi_event_handler *hndl) 
 * Return: 0 on Success

 */

static int scmi_register_notifier(const struct scmi_handle *handle,

				  u8 proto_id, u8 evt_id, u32 *src_id,

				  u8 proto_id, u8 evt_id, const u32 *src_id,

				  struct notifier_block *nb)

{

	int ret = 0;
@@ -1366,7 +1366,7 @@ static int scmi_register_notifier(const struct scmi_handle *handle, 
 * Return: 0 on Success

 */

static int scmi_unregister_notifier(const struct scmi_handle *handle,

				    u8 proto_id, u8 evt_id, u32 *src_id,

				    u8 proto_id, u8 evt_id, const u32 *src_id,

				    struct notifier_block *nb)

{

	u32 evt_key;
@@ -1408,6 +1408,129 @@ static int scmi_unregister_notifier(const struct scmi_handle *handle, 
	return 0;

}



struct scmi_notifier_devres {

	const struct scmi_handle *handle;

	u8 proto_id;

	u8 evt_id;

	u32 __src_id;

	u32 *src_id;

	struct notifier_block *nb;

};



static void scmi_devm_release_notifier(struct device *dev, void *res)

{

	struct scmi_notifier_devres *dres = res;



	scmi_unregister_notifier(dres->handle, dres->proto_id, dres->evt_id,

				 dres->src_id, dres->nb);

}



/**

 * scmi_devm_notifier_register()  - Managed registration of a notifier_block

 * for an event

 * @sdev: A reference to an scmi_device whose embedded struct device is to

 *	  be used for devres accounting.

 * @proto_id: Protocol ID

 * @evt_id: Event ID

 * @src_id: Source ID, when NULL register for events coming form ALL possible

 *	    sources

 * @nb: A standard notifier block to register for the specified event

 *

 * Generic devres managed helper to register a notifier_block against a

 * protocol event.

 */

static int scmi_devm_notifier_register(struct scmi_device *sdev,

				       u8 proto_id, u8 evt_id,

				       const u32 *src_id,

				       struct notifier_block *nb)

{

	int ret;

	struct scmi_notifier_devres *dres;



	dres = devres_alloc(scmi_devm_release_notifier,

			    sizeof(*dres), GFP_KERNEL);

	if (!dres)

		return -ENOMEM;



	ret = scmi_register_notifier(sdev->handle, proto_id,

				     evt_id, src_id, nb);

	if (ret) {

		devres_free(dres);

		return ret;

	}



	dres->handle = sdev->handle;

	dres->proto_id = proto_id;

	dres->evt_id = evt_id;

	dres->nb = nb;

	if (src_id) {

		dres->__src_id = *src_id;

		dres->src_id = &dres->__src_id;

	} else {

		dres->src_id = NULL;

	}

	devres_add(&sdev->dev, dres);



	return ret;

}



static int scmi_devm_notifier_match(struct device *dev, void *res, void *data)

{

	struct scmi_notifier_devres *dres = res;

	struct scmi_notifier_devres *xres = data;



	if (WARN_ON(!dres || !xres))

		return 0;



	return dres->proto_id == xres->proto_id &&

		dres->evt_id == xres->evt_id &&

		dres->nb == xres->nb &&

		((!dres->src_id && !xres->src_id) ||

		  (dres->src_id && xres->src_id &&

		   dres->__src_id == xres->__src_id));

}



/**

 * scmi_devm_notifier_unregister()  - Managed un-registration of a

 * notifier_block for an event

 * @sdev: A reference to an scmi_device whose embedded struct device is to

 *	  be used for devres accounting.

 * @proto_id: Protocol ID

 * @evt_id: Event ID

 * @src_id: Source ID, when NULL register for events coming form ALL possible

 *	    sources

 * @nb: A standard notifier block to register for the specified event

 *

 * Generic devres managed helper to explicitly un-register a notifier_block

 * against a protocol event, which was previously registered using the above

 * @scmi_devm_notifier_register.

 */

static int scmi_devm_notifier_unregister(struct scmi_device *sdev,

					 u8 proto_id, u8 evt_id,

					 const u32 *src_id,

					 struct notifier_block *nb)

{

	int ret;

	struct scmi_notifier_devres dres;



	dres.handle = sdev->handle;

	dres.proto_id = proto_id;

	dres.evt_id = evt_id;

	if (src_id) {

		dres.__src_id = *src_id;

		dres.src_id = &dres.__src_id;

	} else {

		dres.src_id = NULL;

	}



	ret = devres_release(&sdev->dev, scmi_devm_release_notifier,

			     scmi_devm_notifier_match, &dres);



	WARN_ON(ret);



	return ret;

}



/**

 * scmi_protocols_late_init()  - Worker for late initialization

 * @work: The work item to use associated to the proper SCMI instance
@@ -1465,6 +1588,8 @@ static void scmi_protocols_late_init(struct work_struct *work) 
 * directly from an scmi_driver to register its own notifiers.

 */

static const struct scmi_notify_ops notify_ops = {

	.devm_event_notifier_register = scmi_devm_notifier_register,

	.devm_event_notifier_unregister = scmi_devm_notifier_unregister,

	.register_event_notifier = scmi_register_notifier,

	.unregister_event_notifier = scmi_unregister_notifier,

};

include/linux/scmi_protocol.h

+19 −3
Original line number Diff line number Diff line
@@ -544,6 +544,10 @@ struct scmi_voltage_ops { 
/**

 * struct scmi_notify_ops  - represents notifications' operations provided by

 * SCMI core

 * @devm_event_notifier_register: Managed registration of a notifier_block for

 *				  the requested event

 * @devm_event_notifier_unregister: Managed unregistration of a notifier_block

 *				    for the requested event

 * @register_event_notifier: Register a notifier_block for the requested event

 * @unregister_event_notifier: Unregister a notifier_block for the requested

 *			       event
@@ -553,7 +557,9 @@ struct scmi_voltage_ops { 
 * tuple: (proto_id, evt_id, src_id) using the provided register/unregister

 * interface where:

 *

 * @handle: The handle identifying the platform instance to use

 * @sdev: The scmi_device to use when calling the devres managed ops devm_

 * @handle: The handle identifying the platform instance to use, when not

 *	    calling the managed ops devm_

 * @proto_id: The protocol ID as in SCMI Specification

 * @evt_id: The message ID of the desired event as in SCMI Specification

 * @src_id: A pointer to the desired source ID if different sources are
@@ -576,11 +582,21 @@ struct scmi_voltage_ops { 
 * @report: A custom struct describing the specific event delivered

 */

struct scmi_notify_ops {

	int (*devm_event_notifier_register)(struct scmi_device *sdev,

					    u8 proto_id, u8 evt_id,

					    const u32 *src_id,

					    struct notifier_block *nb);

	int (*devm_event_notifier_unregister)(struct scmi_device *sdev,

					      u8 proto_id, u8 evt_id,

					      const u32 *src_id,

					      struct notifier_block *nb);

	int (*register_event_notifier)(const struct scmi_handle *handle,

				       u8 proto_id, u8 evt_id, u32 *src_id,

				       u8 proto_id, u8 evt_id,

				       const u32 *src_id,

				       struct notifier_block *nb);

	int (*unregister_event_notifier)(const struct scmi_handle *handle,

					 u8 proto_id, u8 evt_id, u32 *src_id,

					 u8 proto_id, u8 evt_id,

					 const u32 *src_id,

					 struct notifier_block *nb);

};