drivers/comedi/drivers.c

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

File Facts

System
Linux kernel
Corpus path
drivers/comedi/drivers.c
Extension
.c
Size
37779 bytes
Lines
1290
Domain
Driver Families
Bucket
drivers/comedi
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 (s->async) {
				comedi_buf_alloc(dev, s, 0);
				kfree(s->async);
			}
			kfree(s->readback);
		}
		kfree(dev->subdevices);
		dev->subdevices = NULL;
		dev->n_subdevices = 0;
	}
	kfree(dev->private);
	if (!IS_ERR(dev->pacer))
		kfree(dev->pacer);
	dev->private = NULL;
	dev->pacer = NULL;
	dev->driver = NULL;
	dev->board_name = NULL;
	dev->board_ptr = NULL;
	dev->mmio = NULL;
	dev->iobase = 0;
	dev->iolen = 0;
	dev->ioenabled = false;
	dev->irq = 0;
	dev->read_subdev = NULL;
	dev->write_subdev = NULL;
	dev->open = NULL;
	dev->close = NULL;
	comedi_clear_hw_dev(dev);
}

void comedi_device_detach_locked(struct comedi_device *dev)
{
	lockdep_assert_held_write(&dev->attach_lock);
	lockdep_assert_held(&dev->mutex);
	comedi_device_cancel_all(dev);
	dev->attached = false;
	dev->detach_count++;
	if (dev->driver)
		dev->driver->detach(dev);
	comedi_device_detach_cleanup(dev);
}

void comedi_device_detach(struct comedi_device *dev)
{
	lockdep_assert_held(&dev->mutex);
	down_write(&dev->attach_lock);
	comedi_device_detach_locked(dev);
	up_write(&dev->attach_lock);
}

static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
{
	return -EINVAL;
}

static int insn_device_inval(struct comedi_device *dev,
			     struct comedi_insn *insn, unsigned int *data)
{
	return -EINVAL;
}

static unsigned int get_zero_valid_routes(struct comedi_device *dev,
					  unsigned int n_pairs,
					  unsigned int *pair_data)
{
	return 0;
}

int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
	       struct comedi_insn *insn, unsigned int *data)
{
	return -EINVAL;
}

/**
 * comedi_readback_insn_read() - A generic (*insn_read) for subdevice readback.
 * @dev: COMEDI device.
 * @s: COMEDI subdevice.
 * @insn: COMEDI instruction.
 * @data: Pointer to return the readback data.
 *
 * Handles the %INSN_READ instruction for subdevices that use the readback
 * array allocated by comedi_alloc_subdev_readback().  It may be used
 * directly as the subdevice's handler (@s->insn_read) or called via a
 * wrapper.
 *
 * @insn->n is normally 1, which will read a single value.  If higher, the
 * same element of the readback array will be read multiple times.
 *
 * Returns @insn->n on success, or -EINVAL if @s->readback is NULL.

Annotation

Implementation Notes