staging: comedi: addi_apci_2032: fix the watchdog timer subdevice

The watchdog timer on this board functions exactly like the one on
the apci_1516 board. Fix the i_APCI2032_StartStopWriteWatchdog and
i_APCI2032_ConfigWatchdo functions so that the watchdog follows the
comedi API.

Rename the CamelCase function i_APCI2032_StartStopWriteWatchdog to
apci2032_wdog_insn_writ. This function is used to "ping" the watchdog.

Rename the CamelCase function i_APCI2032_ConfigWatchdog to
apci2032_wdog_insn_config. This function is used to enable/disable
the watchdog and set the timeout.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/addi_apci_2032.c

@@ -56,6 +56,10 @@
 
 static unsigned int ui_InterruptData, ui_Type;
 
+struct apci2032_private {
+	unsigned int wdog_ctrl;
+};
+
 static int i_APCI2032_ConfigDigitalOutput(struct comedi_device *dev,
 					  struct comedi_subdevice *s,
 					  struct comedi_insn *insn,
@@ -106,47 +110,69 @@ static int apci2032_do_insn_bits(struct comedi_device *dev,
 	return insn->n;
 }
 
-static int i_APCI2032_ConfigWatchdog(struct comedi_device *dev,
+/*
+ * 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 apci2032_wdog_insn_config(struct comedi_device *dev,
 				     struct comedi_subdevice *s,
 				     struct comedi_insn *insn,
 				     unsigned int *data)
 {
-	if (data[0] == 0) {
-		/* Disable the watchdog */
-		outl(0x0, dev->iobase + APCI2032_WDOG_CTRL_REG);
-		/* Loading the Reload value */
-		outl(data[1], dev->iobase + APCI2032_WDOG_RELOAD_REG);
-	} else {
-		printk("\nThe input parameters are wrong\n");
+	struct apci2032_private *devpriv = dev->private;
+	unsigned int reload;
+
+	switch (data[0]) {
+	case INSN_CONFIG_ARM:
+		devpriv->wdog_ctrl = APCI2032_WDOG_CTRL_ENABLE;
+		reload = data[1] & s->maxdata;
+		outw(reload, dev->iobase + APCI2032_WDOG_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:
+		devpriv->wdog_ctrl = 0;
+		break;
+	default:
 		return -EINVAL;
 	}
 
+	outw(devpriv->wdog_ctrl, dev->iobase + APCI2032_WDOG_CTRL_REG);
+
 	return insn->n;
 }
 
-static int i_APCI2032_StartStopWriteWatchdog(struct comedi_device *dev,
+static int apci2032_wdog_insn_write(struct comedi_device *dev,
 				    struct comedi_subdevice *s,
 				    struct comedi_insn *insn,
 				    unsigned int *data)
 {
-	switch (data[0]) {
-	case 0:		/* stop the watchdog */
-		outl(0x0, dev->iobase + APCI2032_WDOG_CTRL_REG);
-		break;
-	case 1:		/* start the watchdog */
-		outl(0x0001, dev->iobase + APCI2032_WDOG_CTRL_REG);
-		break;
-	case 2:		/* Software trigger */
-		outl(0x0201, dev->iobase + APCI2032_WDOG_CTRL_REG);
-		break;
-	default:
-		printk("\nSpecified functionality does not exist\n");
+	struct apci2032_private *devpriv = dev->private;
+	int i;
+
+	if (devpriv->wdog_ctrl == 0) {
+		dev_warn(dev->class_dev, "watchdog is disabled\n");
 		return -EINVAL;
 	}
+
+	/* "ping" the watchdog */
+	for (i = 0; i < insn->n; i++) {
+		outw(devpriv->wdog_ctrl | APCI2032_WDOG_CTRL_SW_TRIG,
+			dev->iobase + APCI2032_WDOG_CTRL_REG);
+	}
+
 	return insn->n;
 }
 
-static int apci1516_wdog_insn_read(struct comedi_device *dev,
+static int apci2032_wdog_insn_read(struct comedi_device *dev,
 				   struct comedi_subdevice *s,
 				   struct comedi_insn *insn,
 				   unsigned int *data)
@@ -211,11 +237,17 @@ static int apci2032_auto_attach(struct comedi_device *dev,
 				unsigned long context_unused)
 {
 	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
+	struct apci2032_private *devpriv;
 	struct comedi_subdevice *s;
 	int ret;
 
 	dev->board_name = dev->driver->driver_name;
 
+	devpriv = kzalloc(sizeof(*devpriv), GFP_KERNEL);
+	if (!devpriv)
+		return -ENOMEM;
+	dev->private = devpriv;
+
 	ret = comedi_pci_enable(pcidev, dev->board_name);
 	if (ret)
 		return ret;
@@ -248,12 +280,11 @@ static int apci2032_auto_attach(struct comedi_device *dev,
 	s->type = COMEDI_SUBD_TIMER;
 	s->subdev_flags = SDF_WRITEABLE;
 	s->n_chan = 1;
-	s->maxdata = 0;
-	s->len_chanlist = 1;
+	s->maxdata = 0xff;
 	s->range_table = &range_digital;
-	s->insn_write = i_APCI2032_StartStopWriteWatchdog;
-	s->insn_read = apci1516_wdog_insn_read;
-	s->insn_config = i_APCI2032_ConfigWatchdog;
+	s->insn_write = apci2032_wdog_insn_write;
+	s->insn_read = apci2032_wdog_insn_read;
+	s->insn_config = apci2032_wdog_insn_config;
 
 	apci2032_reset(dev);
 	return 0;