drivers/w1/slaves/w1_ds2780.c

Source file repositories/reference/linux-study-clean/drivers/w1/slaves/w1_ds2780.c

File Facts

System
Linux kernel
Corpus path
drivers/w1/slaves/w1_ds2780.c
Extension
.c
Size
3552 bytes
Lines
161
Domain
Driver Families
Bucket
drivers/w1
Inferred role
Driver Families: exported/initcall integration point
Status
integration 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

if (io) {
			w1_write_8(sl->master, W1_DS2780_WRITE_DATA);
			w1_write_8(sl->master, addr);
			w1_write_block(sl->master, buf, count);
		} else {
			w1_write_8(sl->master, W1_DS2780_READ_DATA);
			w1_write_8(sl->master, addr);
			count = w1_read_block(sl->master, buf, count);
		}
	}

	return count;
}

int w1_ds2780_io(struct device *dev, char *buf, int addr, size_t count,
			int io)
{
	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
	int ret;

	if (!dev)
		return -ENODEV;

	mutex_lock(&sl->master->bus_mutex);

	ret = w1_ds2780_do_io(dev, buf, addr, count, io);

	mutex_unlock(&sl->master->bus_mutex);

	return ret;
}
EXPORT_SYMBOL(w1_ds2780_io);

int w1_ds2780_eeprom_cmd(struct device *dev, int addr, int cmd)
{
	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);

	if (!dev)
		return -EINVAL;

	mutex_lock(&sl->master->bus_mutex);

	if (w1_reset_select_slave(sl) == 0) {
		w1_write_8(sl->master, cmd);
		w1_write_8(sl->master, addr);
	}

	mutex_unlock(&sl->master->bus_mutex);
	return 0;
}
EXPORT_SYMBOL(w1_ds2780_eeprom_cmd);

static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
			     const struct bin_attribute *bin_attr, char *buf,
			     loff_t off, size_t count)
{
	struct device *dev = kobj_to_dev(kobj);

	return w1_ds2780_io(dev, buf, off, count, 0);
}

static const BIN_ATTR_RO(w1_slave, DS2780_DATA_SIZE);

static const struct bin_attribute *const w1_ds2780_bin_attrs[] = {
	&bin_attr_w1_slave,
	NULL,
};

static const struct attribute_group w1_ds2780_group = {
	.bin_attrs = w1_ds2780_bin_attrs,
};

static const struct attribute_group *w1_ds2780_groups[] = {
	&w1_ds2780_group,
	NULL,
};

static int w1_ds2780_add_slave(struct w1_slave *sl)
{
	int ret;
	struct platform_device *pdev;

	pdev = platform_device_alloc("ds2780-battery", PLATFORM_DEVID_AUTO);
	if (!pdev)
		return -ENOMEM;
	pdev->dev.parent = &sl->dev;

	ret = platform_device_add(pdev);
	if (ret)
		goto pdev_add_failed;

Annotation

Implementation Notes