Commit 3d52943b authored by Sudeep Holla's avatar Sudeep Holla Committed by Greg Kroah-Hartman
Browse files

drivers: base: add cpu_device_create to support per-cpu devices 



This patch adds a new function to create per-cpu devices.
This helps in:
1. reusing the device infrastructure to create any cpu related
   attributes and corresponding sysfs instead of creating and
   dealing with raw kobjects directly
2. retaining the legacy path(/sys/devices/system/cpu/..) to support
   existing sysfs ABI
3. avoiding to create links in the bus directory pointing to the
   device as there would be per-cpu instance of these devices with
   the same name since dev->bus is not populated to cpu_sysbus on
   purpose

Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
Tested-by: default avatarStephen Boyd <sboyd@codeaurora.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d6ea8d01

drivers/base/cpu.c

+54 −0
Original line number Diff line number Diff line
@@ -363,6 +363,60 @@ struct device *get_cpu_device(unsigned cpu) 
}

EXPORT_SYMBOL_GPL(get_cpu_device);



static void device_create_release(struct device *dev)

{

	kfree(dev);

}



static struct device *

__cpu_device_create(struct device *parent, void *drvdata,

		    const struct attribute_group **groups,

		    const char *fmt, va_list args)

{

	struct device *dev = NULL;

	int retval = -ENODEV;



	dev = kzalloc(sizeof(*dev), GFP_KERNEL);

	if (!dev) {

		retval = -ENOMEM;

		goto error;

	}



	device_initialize(dev);

	dev->parent = parent;

	dev->groups = groups;

	dev->release = device_create_release;

	dev_set_drvdata(dev, drvdata);



	retval = kobject_set_name_vargs(&dev->kobj, fmt, args);

	if (retval)

		goto error;



	retval = device_add(dev);

	if (retval)

		goto error;



	return dev;



error:

	put_device(dev);

	return ERR_PTR(retval);

}



struct device *cpu_device_create(struct device *parent, void *drvdata,

				 const struct attribute_group **groups,

				 const char *fmt, ...)

{

	va_list vargs;

	struct device *dev;



	va_start(vargs, fmt);

	dev = __cpu_device_create(parent, drvdata, groups, fmt, vargs);

	va_end(vargs);

	return dev;

}

EXPORT_SYMBOL_GPL(cpu_device_create);



#ifdef CONFIG_GENERIC_CPU_AUTOPROBE

static DEVICE_ATTR(modalias, 0444, print_cpu_modalias, NULL);

#endif

include/linux/cpu.h

+4 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 


struct device;

struct device_node;

struct attribute_group;



struct cpu {

	int node_id;		/* The node which contains the CPU */
@@ -39,6 +40,9 @@ extern void cpu_remove_dev_attr(struct device_attribute *attr); 
extern int cpu_add_dev_attr_group(struct attribute_group *attrs);

extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);



extern struct device *cpu_device_create(struct device *parent, void *drvdata,

					const struct attribute_group **groups,

					const char *fmt, ...);

#ifdef CONFIG_HOTPLUG_CPU

extern void unregister_cpu(struct cpu *cpu);

extern ssize_t arch_cpu_probe(const char *, size_t);

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