[PATCH 0/3] firmware: arm_scmi: Minor cleanups in the scmi bus layer

[PATCH 0/3] firmware: arm_scmi: Minor cleanups in the scmi bus layer

[Sudeep Holla]

These cleanup centralizes error logging for SCMI device creation into a
single helper function, _scmi_device_create(), consolidates the device
matching logic into a single function, and ensures that devices must
have a name for registration, removing support for unnamed devices while
matching the devices and drivers for probing.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
Sudeep Holla (3):
      firmware: arm_scmi: Ensure scmi_devices are always matched by name as well
      firmware: arm_scmi: Refactor device matching logic to eliminate duplication
      firmware: arm_scmi: Refactor error logging from SCMI device creation to single helper

 drivers/firmware/arm_scmi/bus.c    | 75 ++++++++++++++++++++------------------
 drivers/firmware/arm_scmi/driver.c |  8 +---
 2 files changed, 40 insertions(+), 43 deletions(-)
---
base-commit: 80e54e84911a923c40d7bee33a34c1b4be148d7a
change-id: 20250312-b4-scmi_minor_cleanup-8f85228d435c

Best regards,
-- 
Regards,
Sudeep

[PATCH 1/3] firmware: arm_scmi: Ensure scmi_devices are always matched by name as well

[Sudeep Holla]

Currently, devices without a name in the id_table cannot register drivers,
and no scmi_device is created without a name via scmi_device_create().
However, the function __scmi_device_create() allows devices with no name,
which are then labeled as "unknown."

Removes support for matching scmi_device instances without a name,
ensuring consistency across the driver registration and probing process.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/firmware/arm_scmi/bus.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
index a3386bf36de508d312e2c4fa2e27ba62ba3776a0..050a5ff5dc96a7df58edff5faeb8c1ec6228b97d 100644
--- a/drivers/firmware/arm_scmi/bus.c
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -214,13 +214,10 @@ scmi_dev_match_id(struct scmi_device *scmi_dev, const struct scmi_driver *scmi_d
 	if (!id)
 		return NULL;
 
-	for (; id->protocol_id; id++)
-		if (id->protocol_id == scmi_dev->protocol_id) {
-			if (!id->name)
-				return id;
-			else if (!strcmp(id->name, scmi_dev->name))
-				return id;
-		}
+	for (; id->protocol_id && id->name; id++)
+		if (id->protocol_id == scmi_dev->protocol_id &&
+		    !strcmp(id->name, scmi_dev->name))
+			return id;
 
 	return NULL;
 }

-- 
2.34.1

[PATCH 2/3] firmware: arm_scmi: Refactor device matching logic to eliminate duplication

[Sudeep Holla]

Currently, the device matching logic is duplicated in two functions:
  - scmi_dev_match() used by the scmi_bus to match scmi_devices with
    scmi_drivers.
  - scmi_child_dev_find() used to check for the presence of a device
    with the same name and protocol_id to avoid adding duplicates to
    the bus.

Refactor the code to eliminate the redundant matching logic and
consolidates the functionality for better maintainability and efficiency.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/firmware/arm_scmi/bus.c | 43 +++++++++++++++++++----------------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
index 050a5ff5dc96a7df58edff5faeb8c1ec6228b97d..a30fd8e05e423e226a63833f309d8d30c400fabd 100644
--- a/drivers/firmware/arm_scmi/bus.c
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -206,52 +206,49 @@ scmi_protocol_table_unregister(const struct scmi_device_id *id_table)
 		scmi_protocol_device_unrequest(entry);
 }
 
-static const struct scmi_device_id *
-scmi_dev_match_id(struct scmi_device *scmi_dev, const struct scmi_driver *scmi_drv)
+static int scmi_dev_match_by_id_table(struct scmi_device *scmi_dev,
+				      const struct scmi_device_id *id_table)
 {
-	const struct scmi_device_id *id = scmi_drv->id_table;
+	if (!id_table || !id_table->name)
+		return 0;
 
-	if (!id)
-		return NULL;
-
-	for (; id->protocol_id && id->name; id++)
-		if (id->protocol_id == scmi_dev->protocol_id &&
-		    !strcmp(id->name, scmi_dev->name))
-			return id;
+	for (; id_table->protocol_id && id_table->name; id_table++)
+		if (id_table->protocol_id == scmi_dev->protocol_id &&
+		    !strcmp(id_table->name, scmi_dev->name))
+			return 1;
+	return 0;
+}
 
-	return NULL;
+static int scmi_dev_match_id(struct scmi_device *scmi_dev,
+			     const struct scmi_driver *scmi_drv)
+{
+	return scmi_dev_match_by_id_table(scmi_dev, scmi_drv->id_table);
 }
 
 static int scmi_dev_match(struct device *dev, const struct device_driver *drv)
 {
 	const struct scmi_driver *scmi_drv = to_scmi_driver(drv);
 	struct scmi_device *scmi_dev = to_scmi_dev(dev);
-	const struct scmi_device_id *id;
-
-	id = scmi_dev_match_id(scmi_dev, scmi_drv);
-	if (id)
-		return 1;
 
-	return 0;
+	return scmi_dev_match_id(scmi_dev, scmi_drv);
 }
 
 static int scmi_match_by_id_table(struct device *dev, const void *data)
 {
-	struct scmi_device *sdev = to_scmi_dev(dev);
+	struct scmi_device *scmi_dev = to_scmi_dev(dev);
 	const struct scmi_device_id *id_table = data;
 
-	return sdev->protocol_id == id_table->protocol_id &&
-		(id_table->name && !strcmp(sdev->name, id_table->name));
+	return scmi_dev_match_by_id_table(scmi_dev, id_table);
 }
 
 static struct scmi_device *scmi_child_dev_find(struct device *parent,
 					       int prot_id, const char *name)
 {
-	struct scmi_device_id id_table;
+	struct scmi_device_id id_table[2] = { 0 };
 	struct device *dev;
 
-	id_table.protocol_id = prot_id;
-	id_table.name = name;
+	id_table[0].protocol_id = prot_id;
+	id_table[0].name = name;
 
 	dev = device_find_child(parent, &id_table, scmi_match_by_id_table);
 	if (!dev)

-- 
2.34.1

[PATCH 3/3] firmware: arm_scmi: Refactor error logging from SCMI device creation to single helper

[Sudeep Holla]

Refactors the error logging related to SCMI device creation. The goal
is to remove duplicated error-handling code and centralize it into a
single helper function: _scmi_device_create().

By doing so, any code redundancy around error logging is avoided, as
error logging during device creation will now be handled by a unified
helper function.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/firmware/arm_scmi/bus.c    | 29 +++++++++++++++++++----------
 drivers/firmware/arm_scmi/driver.c |  8 +-------
 2 files changed, 20 insertions(+), 17 deletions(-)

diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
index a30fd8e05e423e226a63833f309d8d30c400fabd..493e2c63b107fd9063f11034b71d65f567bb0778 100644
--- a/drivers/firmware/arm_scmi/bus.c
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -411,6 +411,20 @@ __scmi_device_create(struct device_node *np, struct device *parent,
 	return NULL;
 }
 
+static struct scmi_device *
+_scmi_device_create(struct device_node *np, struct device *parent,
+		    int protocol, const char *name)
+{
+	struct scmi_device *sdev;
+
+	sdev = __scmi_device_create(np, parent, protocol, name);
+	if (!sdev)
+		pr_err("(%s) Failed to create device for protocol 0x%x (%s)\n",
+		       of_node_full_name(parent->of_node), protocol, name);
+
+	return sdev;
+}
+
 /**
  * scmi_device_create  - A method to create one or more SCMI devices
  *
@@ -443,7 +457,7 @@ struct scmi_device *scmi_device_create(struct device_node *np,
 	struct scmi_device *scmi_dev = NULL;
 
 	if (name)
-		return __scmi_device_create(np, parent, protocol, name);
+		return _scmi_device_create(np, parent, protocol, name);
 
 	mutex_lock(&scmi_requested_devices_mtx);
 	phead = idr_find(&scmi_requested_devices, protocol);
@@ -457,18 +471,13 @@ struct scmi_device *scmi_device_create(struct device_node *np,
 	list_for_each_entry(rdev, phead, node) {
 		struct scmi_device *sdev;
 
-		sdev = __scmi_device_create(np, parent,
-					    rdev->id_table->protocol_id,
-					    rdev->id_table->name);
-		/* Report errors and carry on... */
+		sdev = _scmi_device_create(np, parent,
+					   rdev->id_table->protocol_id,
+					   rdev->id_table->name);
 		if (sdev)
 			scmi_dev = sdev;
-		else
-			pr_err("(%s) Failed to create device for protocol 0x%x (%s)\n",
-			       of_node_full_name(parent->of_node),
-			       rdev->id_table->protocol_id,
-			       rdev->id_table->name);
 	}
+
 	mutex_unlock(&scmi_requested_devices_mtx);
 
 	return scmi_dev;
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 60050da54bf24c0245290e846f91aea62392855b..b80c574cb3bb2f12b2980fc844ea3da10abdc9f1 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -439,14 +439,8 @@ static void scmi_create_protocol_devices(struct device_node *np,
 					 struct scmi_info *info,
 					 int prot_id, const char *name)
 {
-	struct scmi_device *sdev;
-
 	mutex_lock(&info->devreq_mtx);
-	sdev = scmi_device_create(np, info->dev, prot_id, name);
-	if (name && !sdev)
-		dev_err(info->dev,
-			"failed to create device for protocol 0x%X (%s)\n",
-			prot_id, name);
+	scmi_device_create(np, info->dev, prot_id, name);
 	mutex_unlock(&info->devreq_mtx);
 }
 

-- 
2.34.1

Re: [PATCH 0/3] firmware: arm_scmi: Minor cleanups in the scmi bus layer

[Sudeep Holla]

On Wed, Mar 12, 2025 at 11:14:31AM +0000, Sudeep Holla wrote:
> These cleanup centralizes error logging for SCMI device creation into a
> single helper function, _scmi_device_create(), consolidates the device
> matching logic into a single function, and ensures that devices must
> have a name for registration, removing support for unnamed devices while
> matching the devices and drivers for probing.
> 

Please ignore this as I messed by and somehow managed to not include
arm-scmi list with wrong usage of b4 send, will resend soon.

-- 
Regards,
Sudeep

[PATCH 0/3] firmware: arm_scmi: Minor cleanups in the scmi bus layer

[Sudeep Holla]

These cleanup centralizes error logging for SCMI device creation into a
single helper function, _scmi_device_create(), consolidates the device
matching logic into a single function, and ensures that devices must
have a name for registration, removing support for unnamed devices while
matching the devices and drivers for probing.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
Sudeep Holla (3):
      firmware: arm_scmi: Ensure scmi_devices are always matched by name as well
      firmware: arm_scmi: Refactor device matching logic to eliminate duplication
      firmware: arm_scmi: Refactor error logging from SCMI device creation to single helper

 drivers/firmware/arm_scmi/bus.c    | 75 ++++++++++++++++++++------------------
 drivers/firmware/arm_scmi/driver.c |  8 +---
 2 files changed, 40 insertions(+), 43 deletions(-)
---
base-commit: 80e54e84911a923c40d7bee33a34c1b4be148d7a
change-id: 20250312-b4-scmi_minor_cleanup-8f85228d435c

Best regards,
-- 
Regards,
Sudeep