/* * Copyright (C) ST-Ericsson SA 2011 * * Author: Lee Jones <lee.jones@linaro.org> for ST-Ericsson. * License terms:  GNU General Public License (GPL), version 2 */ #include <linux/sysfs.h>#include <linux/module.h>#include <linux/init.h>#include <linux/stat.h>#include <linux/slab.h>#include <linux/idr.h>#include <linux/spinlock.h>#include <linux/sys_soc.h>#include <linux/err.h> static DEFINE_IDA(soc_ida);static DEFINE_SPINLOCK(soc_lock); static ssize_t soc_info_get(struct device *dev,			    struct device_attribute *attr,			    char *buf); struct soc_device {	struct device dev;	struct soc_device_attribute *attr;	int soc_dev_num;}; static struct bus_type soc_bus_type = {	.name  = "soc",}; static DEVICE_ATTR(machine,  S_IRUGO, soc_info_get,  NULL);static DEVICE_ATTR(family,   S_IRUGO, soc_info_get,  NULL);static DEVICE_ATTR(soc_id,   S_IRUGO, soc_info_get,  NULL);static DEVICE_ATTR(revision, S_IRUGO, soc_info_get,  NULL); struct device *soc_device_to_device(struct soc_device *soc_dev){	return &soc_dev->dev;} static umode_t soc_attribute_mode(struct kobject *kobj,                                 struct attribute *attr,                                 int index){	struct device *dev = container_of(kobj, struct device, kobj);	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev); 	if ((attr == &dev_attr_machine.attr)	    && (soc_dev->attr->machine != NULL))		return attr->mode;	if ((attr == &dev_attr_family.attr)	    && (soc_dev->attr->family != NULL))		return attr->mode;	if ((attr == &dev_attr_revision.attr)	    && (soc_dev->attr->revision != NULL))		return attr->mode;	if ((attr == &dev_attr_soc_id.attr)	    && (soc_dev->attr->soc_id != NULL))	        return attr->mode; 	/* Unknown or unfilled attribute. */	return 0;} static ssize_t soc_info_get(struct device *dev,			    struct device_attribute *attr,			    char *buf){	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev); 	if (attr == &dev_attr_machine)		return sprintf(buf, "%s\n", soc_dev->attr->machine);	if (attr == &dev_attr_family)		return sprintf(buf, "%s\n", soc_dev->attr->family);	if (attr == &dev_attr_revision)		return sprintf(buf, "%s\n", soc_dev->attr->revision);	if (attr == &dev_attr_soc_id)		return sprintf(buf, "%s\n", soc_dev->attr->soc_id); 	return -EINVAL; } static struct attribute *soc_attr[] = {	&dev_attr_machine.attr,	&dev_attr_family.attr,	&dev_attr_soc_id.attr,	&dev_attr_revision.attr,	NULL,}; static const struct attribute_group soc_attr_group = {	.attrs = soc_attr,	.is_visible = soc_attribute_mode,}; static const struct attribute_group *soc_attr_groups[] = {	&soc_attr_group,	NULL,}; static void soc_release(struct device *dev){	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev); 	kfree(soc_dev);} struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr){	struct soc_device *soc_dev;	int ret; 	soc_dev = kzalloc(sizeof(*soc_dev), GFP_KERNEL);	if (!soc_dev) {	        ret = -ENOMEM;		goto out1;	} 	/* Fetch a unique (reclaimable) SOC ID. */	do {		if (!ida_pre_get(&soc_ida, GFP_KERNEL)) {			ret = -ENOMEM;			goto out2;		} 		spin_lock(&soc_lock);		ret = ida_get_new(&soc_ida, &soc_dev->soc_dev_num);		spin_unlock(&soc_lock); 	} while (ret == -EAGAIN); 	if (ret)	         goto out2; 	soc_dev->attr = soc_dev_attr;	soc_dev->dev.bus = &soc_bus_type;	soc_dev->dev.groups = soc_attr_groups;	soc_dev->dev.release = soc_release; 	dev_set_name(&soc_dev->dev, "soc%d", soc_dev->soc_dev_num); 	ret = device_register(&soc_dev->dev);	if (ret)		goto out3; 	return soc_dev; out3:	ida_remove(&soc_ida, soc_dev->soc_dev_num);out2:	kfree(soc_dev);out1:	return ERR_PTR(ret);} /* Ensure soc_dev->attr is freed prior to calling soc_device_unregister. */void soc_device_unregister(struct soc_device *soc_dev){	ida_remove(&soc_ida, soc_dev->soc_dev_num); 	device_unregister(&soc_dev->dev);} static int __init soc_bus_register(void){	return bus_register(&soc_bus_type);}core_initcall(soc_bus_register); static void __exit soc_bus_unregister(void){	ida_destroy(&soc_ida); 	bus_unregister(&soc_bus_type);}module_exit(soc_bus_unregister);