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serdev: bus-code clean ups

PATCH In review Johan Hovold 2 participants 5 messages Jan 9, 2018 – Jan 19, 2018

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#0 lore raw

v2 cover serdev: bus-code clean ups

As noted by Hans, we currently fail to generate uevents for ACPI serdev controller as they do not have any ACPI companions from which ACPI modaliases are constructed.

In fact, we should not have been generating modaliases for controllers in the first place as controllers are not bound to drivers.

This series applies on top of Hans's minimal fix which suppresses the uevent errors for ACPI controllers (even though it could replace it entirely if preferred).

Johan

v2
- add the missing static keyword for the modalias attribute when moving the definition (noted by Greg)

Johan Hovold (2):
serdev: do not generate modaliases for controllers
serdev: only match serdev devices

 drivers/tty/serdev/core.c | 80 +++++++++++++++++++++++++----------------------
 1 file changed, 42 insertions(+), 38 deletions(-)
Signature · 1 line
2.15.1
#1 lore raw

PATCH v2 1/2 serdev: do not generate modaliases for controllers

Serdev controllers are not bound to any drivers and it therefore makes no sense to generate modaliases for them.

This has already been fixed separately for ACPI controllers for which uevent errors were also being logged during probe due to the missing ACPI companions (from which ACPI modaliases are generated).

This patch moves the modalias handling from the bus type to the client device type. Specifically, this means that only serdev devices (a.k.a. clients or slaves) will have have MODALIAS fields in their uevent environments and corresponding modalias sysfs attributes.

Also add the missing static keyword for the modalias device attribute when moving the definition.

---
 drivers/tty/serdev/core.c | 72 ++++++++++++++++++++++-------------------------
 1 file changed, 34 insertions(+), 38 deletions(-)
drivers/tty/serdev/core.c +34 -38
index 5dc88f61f506..c8c43834477b 100644
@@ -19,6 +19,38 @@
 static bool is_registered;
 static DEFINE_IDA(ctrl_ida);
 
+static ssize_t modalias_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	int len;
+
+	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
+	if (len != -ENODEV)
+		return len;
+
+	return of_device_modalias(dev, buf, PAGE_SIZE);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *serdev_device_attrs[] = {
+	&dev_attr_modalias.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(serdev_device);
+
+static int serdev_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	int rc;
+
+	/* TODO: platform modalias */
+
+	rc = acpi_device_uevent_modalias(dev, env);
+	if (rc != -ENODEV)
+		return rc;
+
+	return of_device_uevent_modalias(dev, env);
+}
+
 static void serdev_device_release(struct device *dev)
 {
 	struct serdev_device *serdev = to_serdev_device(dev);
@@ -26,6 +58,8 @@ static void serdev_device_release(struct device *dev)
 }
 
 static const struct device_type serdev_device_type = {
+	.groups		= serdev_device_groups,
+	.uevent		= serdev_device_uevent,
 	.release	= serdev_device_release,
 };
 
@@ -49,23 +83,6 @@ static int serdev_device_match(struct device *dev, struct device_driver *drv)
 	return of_driver_match_device(dev, drv);
 }
 
-static int serdev_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
-	int rc;
-
-	/* TODO: platform modalias */
-
-	/* ACPI enumerated controllers do not have a modalias */
-	if (!dev->of_node && dev->type == &serdev_ctrl_type)
-		return 0;
-
-	rc = acpi_device_uevent_modalias(dev, env);
-	if (rc != -ENODEV)
-		return rc;
-
-	return of_device_uevent_modalias(dev, env);
-}
-
 /**
  * serdev_device_add() - add a device previously constructed via serdev_device_alloc()
  * @serdev:	serdev_device to be added
@@ -305,32 +322,11 @@ static int serdev_drv_remove(struct device *dev)
 	return 0;
 }
 
-static ssize_t modalias_show(struct device *dev,
-			     struct device_attribute *attr, char *buf)
-{
-	int len;
-
-	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
-	if (len != -ENODEV)
-		return len;
-
-	return of_device_modalias(dev, buf, PAGE_SIZE);
-}
-DEVICE_ATTR_RO(modalias);
-
-static struct attribute *serdev_device_attrs[] = {
-	&dev_attr_modalias.attr,
-	NULL,
-};
-ATTRIBUTE_GROUPS(serdev_device);
-
 static struct bus_type serdev_bus_type = {
 	.name		= "serial",
 	.match		= serdev_device_match,
 	.probe		= serdev_drv_probe,
 	.remove		= serdev_drv_remove,
-	.uevent		= serdev_uevent,
-	.dev_groups	= serdev_device_groups,
 };
 
 /**
Signature · 1 line
2.15.1
Reviewed-by on v2 1/2
#2 lore raw

Re: [PATCH v2 1/2] serdev: do not generate modaliases for controllers

Hi,

Quoted 12 lines · Johan Hovold

Serdev controllers are not bound to any drivers and it therefore makes no sense to generate modaliases for them.

This has already been fixed separately for ACPI controllers for which uevent errors were also being logged during probe due to the missing ACPI companions (from which ACPI modaliases are generated).

This patch moves the modalias handling from the bus type to the client device type. Specifically, this means that only serdev devices (a.k.a. clients or slaves) will have have MODALIAS fields in their uevent environments and corresponding modalias sysfs attributes.

Quoted 6 lines

Also add the missing static keyword for the modalias device attribute when moving the definition.

---

-- Sebastian

Quoted 115 lines
 drivers/tty/serdev/core.c | 72 ++++++++++++++++++++++-------------------------
 1 file changed, 34 insertions(+), 38 deletions(-)
drivers/tty/serdev/core.c +34 -38
index 5dc88f61f506..c8c43834477b 100644
@@ -19,6 +19,38 @@
 static bool is_registered;
 static DEFINE_IDA(ctrl_ida);
 
+static ssize_t modalias_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	int len;
+
+	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
+	if (len != -ENODEV)
+		return len;
+
+	return of_device_modalias(dev, buf, PAGE_SIZE);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *serdev_device_attrs[] = {
+	&dev_attr_modalias.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(serdev_device);
+
+static int serdev_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	int rc;
+
+	/* TODO: platform modalias */
+
+	rc = acpi_device_uevent_modalias(dev, env);
+	if (rc != -ENODEV)
+		return rc;
+
+	return of_device_uevent_modalias(dev, env);
+}
+
 static void serdev_device_release(struct device *dev)
 {
 	struct serdev_device *serdev = to_serdev_device(dev);
@@ -26,6 +58,8 @@ static void serdev_device_release(struct device *dev)
 }
 
 static const struct device_type serdev_device_type = {
+	.groups		= serdev_device_groups,
+	.uevent		= serdev_device_uevent,
 	.release	= serdev_device_release,
 };
 
@@ -49,23 +83,6 @@ static int serdev_device_match(struct device *dev, struct device_driver *drv)
 	return of_driver_match_device(dev, drv);
 }
 
-static int serdev_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
-	int rc;
-
-	/* TODO: platform modalias */
-
-	/* ACPI enumerated controllers do not have a modalias */
-	if (!dev->of_node && dev->type == &serdev_ctrl_type)
-		return 0;
-
-	rc = acpi_device_uevent_modalias(dev, env);
-	if (rc != -ENODEV)
-		return rc;
-
-	return of_device_uevent_modalias(dev, env);
-}
-
 /**
  * serdev_device_add() - add a device previously constructed via serdev_device_alloc()
  * @serdev:	serdev_device to be added
@@ -305,32 +322,11 @@ static int serdev_drv_remove(struct device *dev)
 	return 0;
 }
 
-static ssize_t modalias_show(struct device *dev,
-			     struct device_attribute *attr, char *buf)
-{
-	int len;
-
-	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
-	if (len != -ENODEV)
-		return len;
-
-	return of_device_modalias(dev, buf, PAGE_SIZE);
-}
-DEVICE_ATTR_RO(modalias);
-
-static struct attribute *serdev_device_attrs[] = {
-	&dev_attr_modalias.attr,
-	NULL,
-};
-ATTRIBUTE_GROUPS(serdev_device);
-
 static struct bus_type serdev_bus_type = {
 	.name		= "serial",
 	.match		= serdev_device_match,
 	.probe		= serdev_drv_probe,
 	.remove		= serdev_drv_remove,
-	.uevent		= serdev_uevent,
-	.dev_groups	= serdev_device_groups,
 };
 
 /**
Signature · 1 line
2.15.1
#3 lore raw

PATCH v2 2/2 serdev: only match serdev devices

In reply to Johan Hovold

Only serdev devices (a.k.a. clients or slaves) are bound to drivers so bail out early from match() in case the device is not a serdev device (i.e. if it's a serdev controller).

---
 drivers/tty/serdev/core.c | 8 ++++++++
 1 file changed, 8 insertions(+)
drivers/tty/serdev/core.c +8 -0
index c8c43834477b..f710862f5c06 100644
@@ -63,6 +63,11 @@ static const struct device_type serdev_device_type = {
 	.release	= serdev_device_release,
 };
 
+static bool is_serdev_device(const struct device *dev)
+{
+	return dev->type == &serdev_device_type;
+}
+
 static void serdev_ctrl_release(struct device *dev)
 {
 	struct serdev_controller *ctrl = to_serdev_controller(dev);
@@ -76,6 +81,9 @@ static const struct device_type serdev_ctrl_type = {
 
 static int serdev_device_match(struct device *dev, struct device_driver *drv)
 {
+	if (!is_serdev_device(dev))
+		return 0;
+
 	/* TODO: platform matching */
 	if (acpi_driver_match_device(dev, drv))
 		return 1;
Signature · 1 line
2.15.1
Reviewed-by on v2 2/2
#4 lore raw

Re: [PATCH v2 2/2] serdev: only match serdev devices

Hi,

Quoted 6 lines · Johan Hovold

Only serdev devices (a.k.a. clients or slaves) are bound to drivers so bail out early from match() in case the device is not a serdev device (i.e. if it's a serdev controller).

---

-- Sebastian

Quoted 32 lines
 drivers/tty/serdev/core.c | 8 ++++++++
 1 file changed, 8 insertions(+)
drivers/tty/serdev/core.c +8 -0
index c8c43834477b..f710862f5c06 100644
@@ -63,6 +63,11 @@ static const struct device_type serdev_device_type = {
 	.release	= serdev_device_release,
 };
 
+static bool is_serdev_device(const struct device *dev)
+{
+	return dev->type == &serdev_device_type;
+}
+
 static void serdev_ctrl_release(struct device *dev)
 {
 	struct serdev_controller *ctrl = to_serdev_controller(dev);
@@ -76,6 +81,9 @@ static const struct device_type serdev_ctrl_type = {
 
 static int serdev_device_match(struct device *dev, struct device_driver *drv)
 {
+	if (!is_serdev_device(dev))
+		return 0;
+
 	/* TODO: platform matching */
 	if (acpi_driver_match_device(dev, drv))
 		return 1;
Signature · 1 line
2.15.1