[PATCH 25/28] Driver core: add device_type to struct device

From: Greg KH
Date: Wed Feb 07 2007 - 19:36:58 EST


From: Kay Sievers <kay.sievers@xxxxxxxxxx>

This allows us to add type specific attributes, uevent vars and
release funtions.

A subsystem can carry different types of devices like the "block"
subsys has disks and partitions. Both types create a different set
of attributes, but belong to the same subsystem.

This corresponds to the low level objects:
kobject -> device (object/device data)
kobj_type -> device_type (type of object/device we are embedded in)
kset -> class/bus (list of objects/devices of a subsystem)

Signed-off-by: Kay Sievers <kay.sievers@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/base/core.c | 57 ++++++++++++++++++++++++++++-------------
drivers/usb/input/hid-lgff.c | 4 +-
include/linux/device.h | 8 ++++++
3 files changed, 49 insertions(+), 20 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 7a5336f..34ac187 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -95,6 +95,8 @@ static void device_release(struct kobject * kobj)

if (dev->release)
dev->release(dev);
+ else if (dev->type && dev->type->release)
+ dev->type->release(dev);
else if (dev->class && dev->class->dev_release)
dev->class->dev_release(dev);
else {
@@ -206,19 +208,25 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
if (dev->bus && dev->bus->uevent) {
/* have the bus specific function add its stuff */
retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size);
- if (retval) {
- pr_debug ("%s - uevent() returned %d\n",
+ if (retval)
+ pr_debug ("%s: bus uevent() returned %d\n",
__FUNCTION__, retval);
- }
}

if (dev->class && dev->class->dev_uevent) {
/* have the class specific function add its stuff */
retval = dev->class->dev_uevent(dev, envp, num_envp, buffer, buffer_size);
- if (retval) {
- pr_debug("%s - dev_uevent() returned %d\n",
- __FUNCTION__, retval);
- }
+ if (retval)
+ pr_debug("%s: class uevent() returned %d\n",
+ __FUNCTION__, retval);
+ }
+
+ if (dev->type && dev->type->uevent) {
+ /* have the device type specific fuction add its stuff */
+ retval = dev->type->uevent(dev, envp, num_envp, buffer, buffer_size);
+ if (retval)
+ pr_debug("%s: dev_type uevent() returned %d\n",
+ __FUNCTION__, retval);
}

return retval;
@@ -269,37 +277,50 @@ static void device_remove_groups(struct device *dev)
static int device_add_attrs(struct device *dev)
{
struct class *class = dev->class;
+ struct device_type *type = dev->type;
int error = 0;
int i;

- if (!class)
- return 0;
-
- if (class->dev_attrs) {
+ if (class && class->dev_attrs) {
for (i = 0; attr_name(class->dev_attrs[i]); i++) {
error = device_create_file(dev, &class->dev_attrs[i]);
if (error)
break;
}
+ if (error)
+ while (--i >= 0)
+ device_remove_file(dev, &class->dev_attrs[i]);
}
- if (error)
- while (--i >= 0)
- device_remove_file(dev, &class->dev_attrs[i]);
+
+ if (type && type->attrs) {
+ for (i = 0; attr_name(type->attrs[i]); i++) {
+ error = device_create_file(dev, &type->attrs[i]);
+ if (error)
+ break;
+ }
+ if (error)
+ while (--i >= 0)
+ device_remove_file(dev, &type->attrs[i]);
+ }
+
return error;
}

static void device_remove_attrs(struct device *dev)
{
struct class *class = dev->class;
+ struct device_type *type = dev->type;
int i;

- if (!class)
- return;
-
- if (class->dev_attrs) {
+ if (class && class->dev_attrs) {
for (i = 0; attr_name(class->dev_attrs[i]); i++)
device_remove_file(dev, &class->dev_attrs[i]);
}
+
+ if (type && type->attrs) {
+ for (i = 0; attr_name(type->attrs[i]); i++)
+ device_remove_file(dev, &type->attrs[i]);
+ }
}


diff --git a/drivers/usb/input/hid-lgff.c b/drivers/usb/input/hid-lgff.c
index e474662..4f4fc3b 100644
--- a/drivers/usb/input/hid-lgff.c
+++ b/drivers/usb/input/hid-lgff.c
@@ -32,7 +32,7 @@
#include <linux/hid.h>
#include "usbhid.h"

-struct device_type {
+struct dev_type {
u16 idVendor;
u16 idProduct;
const signed short *ff;
@@ -48,7 +48,7 @@ static const signed short ff_joystick[] = {
-1
};

-static const struct device_type devices[] = {
+static const struct dev_type devices[] = {
{ 0x046d, 0xc211, ff_rumble },
{ 0x046d, 0xc219, ff_rumble },
{ 0x046d, 0xc283, ff_joystick },
diff --git a/include/linux/device.h b/include/linux/device.h
index da72219..e1e164f 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -328,6 +328,13 @@ extern struct class_device *class_device_create(struct class *cls,
__attribute__((format(printf,5,6)));
extern void class_device_destroy(struct class *cls, dev_t devt);

+struct device_type {
+ struct device_attribute *attrs;
+ int (*uevent)(struct device *dev, char **envp, int num_envp,
+ char *buffer, int buffer_size);
+ void (*release)(struct device *dev);
+};
+
/* interface for exporting device attributes */
struct device_attribute {
struct attribute attr;
@@ -356,6 +363,7 @@ struct device {

struct kobject kobj;
char bus_id[BUS_ID_SIZE]; /* position on parent bus */
+ struct device_type *type;
unsigned is_registered:1;
struct device_attribute uevent_attr;
struct device_attribute *devt_attr;
--
1.4.4.4

-
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