drivers/comedi/drivers/addi_watchdog.c

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

File Facts

System
Linux kernel
Corpus path
drivers/comedi/drivers/addi_watchdog.c
Extension
.c
Size
3212 bytes
Lines
130
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

struct addi_watchdog_private {
	unsigned long iobase;
	unsigned int wdog_ctrl;
};

/*
 * The watchdog subdevice is configured with two INSN_CONFIG instructions:
 *
 * Enable the watchdog and set the reload timeout:
 *	data[0] = INSN_CONFIG_ARM
 *	data[1] = timeout reload value
 *
 * Disable the watchdog:
 *	data[0] = INSN_CONFIG_DISARM
 */
static int addi_watchdog_insn_config(struct comedi_device *dev,
				     struct comedi_subdevice *s,
				     struct comedi_insn *insn,
				     unsigned int *data)
{
	struct addi_watchdog_private *spriv = s->private;
	unsigned int reload;

	switch (data[0]) {
	case INSN_CONFIG_ARM:
		spriv->wdog_ctrl = ADDI_TCW_CTRL_ENA;
		reload = data[1] & s->maxdata;
		outl(reload, spriv->iobase + ADDI_TCW_RELOAD_REG);

		/* Time base is 20ms, let the user know the timeout */
		dev_info(dev->class_dev, "watchdog enabled, timeout:%dms\n",
			 20 * reload + 20);
		break;
	case INSN_CONFIG_DISARM:
		spriv->wdog_ctrl = 0;
		break;
	default:
		return -EINVAL;
	}

	outl(spriv->wdog_ctrl, spriv->iobase + ADDI_TCW_CTRL_REG);

	return insn->n;
}

static int addi_watchdog_insn_read(struct comedi_device *dev,
				   struct comedi_subdevice *s,
				   struct comedi_insn *insn,
				   unsigned int *data)
{
	struct addi_watchdog_private *spriv = s->private;
	int i;

	for (i = 0; i < insn->n; i++)
		data[i] = inl(spriv->iobase + ADDI_TCW_STATUS_REG);

	return insn->n;
}

static int addi_watchdog_insn_write(struct comedi_device *dev,
				    struct comedi_subdevice *s,
				    struct comedi_insn *insn,
				    unsigned int *data)
{
	struct addi_watchdog_private *spriv = s->private;
	int i;

	if (spriv->wdog_ctrl == 0) {
		dev_warn(dev->class_dev, "watchdog is disabled\n");
		return -EINVAL;
	}

	/* "ping" the watchdog */
	for (i = 0; i < insn->n; i++) {
		outl(spriv->wdog_ctrl | ADDI_TCW_CTRL_TRIG,
		     spriv->iobase + ADDI_TCW_CTRL_REG);
	}

	return insn->n;
}

void addi_watchdog_reset(unsigned long iobase)
{
	outl(0x0, iobase + ADDI_TCW_CTRL_REG);
	outl(0x0, iobase + ADDI_TCW_RELOAD_REG);
}
EXPORT_SYMBOL_GPL(addi_watchdog_reset);

int addi_watchdog_init(struct comedi_subdevice *s, unsigned long iobase)
{

Annotation

Implementation Notes