drivers/base/core.c

Source file repositories/reference/linux-study-clean/drivers/base/core.c

File Facts

System
Linux kernel
Corpus path
drivers/base/core.c
Extension
.c
Size
151293 bytes
Lines
5435
Domain
Driver Families
Bucket
drivers/base
Inferred role
Driver Families: operation-table or driver-model contract
Status
pattern implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct device_driver *drv;

	/* dev->driver can change to NULL underneath us because of unbinding,
	 * so be careful about accessing it.  dev->bus and dev->class should
	 * never change once they are set, so they don't need special care.
	 */
	drv = READ_ONCE(dev->driver);
	return drv ? drv->name : dev_bus_name(dev);
}
EXPORT_SYMBOL(dev_driver_string);

#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)

static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr,
			     char *buf)
{
	struct device_attribute *dev_attr = to_dev_attr(attr);
	struct device *dev = kobj_to_dev(kobj);
	ssize_t ret = -EIO;

	if (dev_attr->show)
		ret = dev_attr->show(dev, dev_attr, buf);
	else if (dev_attr->show_const)
		ret = dev_attr->show_const(dev, dev_attr, buf);
	if (ret >= (ssize_t)PAGE_SIZE) {
		printk("dev_attr_show: %pS/%pS returned bad count\n",
				dev_attr->show, dev_attr->show_const);
	}
	return ret;
}

static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr,
			      const char *buf, size_t count)
{
	struct device_attribute *dev_attr = to_dev_attr(attr);
	struct device *dev = kobj_to_dev(kobj);
	ssize_t ret = -EIO;

	if (dev_attr->store)
		ret = dev_attr->store(dev, dev_attr, buf, count);
	else if (dev_attr->store_const)
		ret = dev_attr->store_const(dev, dev_attr, buf, count);
	return ret;
}

static const struct sysfs_ops dev_sysfs_ops = {
	.show	= dev_attr_show,
	.store	= dev_attr_store,
};

#define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr)

ssize_t device_store_ulong(struct device *dev,
			   struct device_attribute *attr,
			   const char *buf, size_t size)
{
	struct dev_ext_attribute *ea = to_ext_attr(attr);
	int ret;
	unsigned long new;

	ret = kstrtoul(buf, 0, &new);
	if (ret)
		return ret;
	*(unsigned long *)(ea->var) = new;
	/* Always return full write size even if we didn't consume all */
	return size;
}
EXPORT_SYMBOL_GPL(device_store_ulong);

ssize_t device_show_ulong(struct device *dev,
			  struct device_attribute *attr,
			  char *buf)
{
	struct dev_ext_attribute *ea = to_ext_attr(attr);
	return sysfs_emit(buf, "%lx\n", *(unsigned long *)(ea->var));
}
EXPORT_SYMBOL_GPL(device_show_ulong);

ssize_t device_store_int(struct device *dev,
			 struct device_attribute *attr,
			 const char *buf, size_t size)
{
	struct dev_ext_attribute *ea = to_ext_attr(attr);
	int ret;
	long new;

	ret = kstrtol(buf, 0, &new);
	if (ret)
		return ret;

Annotation

Implementation Notes