staging: comedi: addi_apci_1564: add Change-of-State interrupt subdevice and required functions

This board supports an interrupt that can be generated by an AND/OR
combination of 16 of the input channels.

Create a separate subdevice to handle this interrupt.

The apci1564_di_config() function is used to configure which
inputs are used to generate the interrupt. Currently this function
is broken since it does not follow the comedi API for insn_config
functions. Fix this function by implementing the config instruction
INSN_CONFIG_DIGITAL_TRIG.

Add the remaining subdevice operations necessary for the interrupt
subdevice to support async commands.
Signed-off-by: Chase Southwood <chase.southwood@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/addi-data/hwdrv_apci1564.c

@@ -26,12 +26,12 @@
 #define APCI1564_ADDRESS_RANGE				128
 
 /* Digital Input IRQ Function Selection */
-#define ADDIDATA_OR					0
-#define ADDIDATA_AND					1
+#define APCI1564_DI_INT_OR				(0 << 1)
+#define APCI1564_DI_INT_AND				(1 << 1)
 
 /* Digital Input Interrupt Enable Disable. */
-#define APCI1564_DIGITAL_IP_INTERRUPT_ENABLE		0x4
-#define APCI1564_DIGITAL_IP_INTERRUPT_DISABLE		0xfffffffb
+#define APCI1564_DI_INT_ENABLE				0x4
+#define APCI1564_DI_INT_DISABLE				0xfffffffb
 
 /* Digital Output Interrupt Enable Disable. */
 #define APCI1564_DIGITAL_OP_VCC_INTERRUPT_ENABLE	0x1
@@ -89,42 +89,6 @@
 #define APCI1564_TCW_WARN_TIMEVAL_REG(x)		(0x18 + ((x) * 0x20))
 #define APCI1564_TCW_WARN_TIMEBASE_REG(x)		(0x1c + ((x) * 0x20))
 
-/*
- * Configures the digital input Subdevice
- *
- * data[0] 1 = Enable interrupt, 0 = Disable interrupt
- * data[1] 0 = ADDIDATA Interrupt OR LOGIC, 1 = ADDIDATA Interrupt AND LOGIC
- * data[2] Interrupt mask for the mode 1
- * data[3] Interrupt mask for the mode 2
- */
-static int apci1564_di_config(struct comedi_device *dev,
-			      struct comedi_subdevice *s,
-			      struct comedi_insn *insn,
-			      unsigned int *data)
-{
-	struct apci1564_private *devpriv = dev->private;
-
-	devpriv->tsk_current = current;
-
-	/* Set the digital input logic */
-	if (data[0] == 1) {
-		data[2] = data[2] << 4;
-		data[3] = data[3] << 4;
-		outl(data[2], devpriv->amcc_iobase + APCI1564_DI_INT_MODE1_REG);
-		outl(data[3], devpriv->amcc_iobase + APCI1564_DI_INT_MODE2_REG);
-		if (data[1] == ADDIDATA_OR)
-			outl(0x4, devpriv->amcc_iobase + APCI1564_DI_IRQ_REG);
-		else
-			outl(0x6, devpriv->amcc_iobase + APCI1564_DI_IRQ_REG);
-	} else {
-		outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE1_REG);
-		outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE2_REG);
-		outl(0x0, devpriv->amcc_iobase + APCI1564_DI_IRQ_REG);
-	}
-
-	return insn->n;
-}
-
 /*
  * Configures The Digital Output Subdevice.
  *

drivers/staging/comedi/drivers/addi_apci_1564.c

@@ -8,6 +8,9 @@
 
 struct apci1564_private {
 	unsigned int amcc_iobase;	/* base of AMCC I/O registers */
+	unsigned int mode1;		/* riding-edge/high level channels */
+	unsigned int mode2;		/* falling-edge/low level channels */
+	unsigned int ctrl;		/* interrupt mode OR (edge) . AND (level) */
 	unsigned int do_int_type;
 	unsigned char timer_select_mode;
 	unsigned char mode_select_register;
@@ -16,6 +19,38 @@ struct apci1564_private {
 
 #include "addi-data/hwdrv_apci1564.c"
 
+static int apci1564_reset(struct comedi_device *dev)
+{
+	struct apci1564_private *devpriv = dev->private;
+
+	devpriv->do_int_type = 0;
+
+	/* Disable the input interrupts and reset status register */
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_IRQ_REG);
+	inl(devpriv->amcc_iobase + APCI1564_DI_INT_STATUS_REG);
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE1_REG);
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE2_REG);
+
+	/* Reset the output channels and disable interrupts */
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DO_REG);
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DO_INT_CTRL_REG);
+
+	/* Reset the watchdog registers */
+	addi_watchdog_reset(devpriv->amcc_iobase + APCI1564_WDOG_REG);
+
+	/* Reset the timer registers */
+	outl(0x0, devpriv->amcc_iobase + APCI1564_TIMER_CTRL_REG);
+	outl(0x0, devpriv->amcc_iobase + APCI1564_TIMER_RELOAD_REG);
+
+	/* Reset the counter registers */
+	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER1));
+	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER2));
+	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER3));
+	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER4));
+
+	return 0;
+}
+
 static irqreturn_t v_ADDI_Interrupt(int irq, void *d)
 {
 	apci1564_interrupt(irq, d);
@@ -51,34 +86,187 @@ static int apci1564_do_insn_bits(struct comedi_device *dev,
 	return insn->n;
 }
 
-static int apci1564_reset(struct comedi_device *dev)
+/*
+ * Change-Of-State (COS) interrupt configuration
+ *
+ * Channels 0 to 15 are interruptible. These channels can be configured
+ * to generate interrupts based on AND/OR logic for the desired channels.
+ *
+ *	OR logic
+ *		- reacts to rising or falling edges
+ *		- interrupt is generated when any enabled channel
+ *		  meet the desired interrupt condition
+ *
+ *	AND logic
+ *		- reacts to changes in level of the selected inputs
+ *		- interrupt is generated when all enabled channels
+ *		  meet the desired interrupt condition
+ *		- after an interrupt, a change in level must occur on
+ *		  the selected inputs to release the IRQ logic
+ *
+ * The COS interrupt must be configured before it can be enabled.
+ *
+ *	data[0] : INSN_CONFIG_DIGITAL_TRIG
+ *	data[1] : trigger number (= 0)
+ *	data[2] : configuration operation:
+ *	          COMEDI_DIGITAL_TRIG_DISABLE = no interrupts
+ *	          COMEDI_DIGITAL_TRIG_ENABLE_EDGES = OR (edge) interrupts
+ *	          COMEDI_DIGITAL_TRIG_ENABLE_LEVELS = AND (level) interrupts
+ *	data[3] : left-shift for data[4] and data[5]
+ *	data[4] : rising-edge/high level channels
+ *	data[5] : falling-edge/low level channels
+ */
+static int apci1564_cos_insn_config(struct comedi_device *dev,
+				    struct comedi_subdevice *s,
+				    struct comedi_insn *insn,
+				    unsigned int *data)
 {
 	struct apci1564_private *devpriv = dev->private;
+	unsigned int shift, oldmask;
+
+	switch (data[0]) {
+	case INSN_CONFIG_DIGITAL_TRIG:
+		if (data[1] != 0)
+			return -EINVAL;
+		shift = data[3];
+		oldmask = (1U << shift) - 1;
+		switch (data[2]) {
+		case COMEDI_DIGITAL_TRIG_DISABLE:
+			devpriv->ctrl = 0;
+			devpriv->mode1 = 0;
+			devpriv->mode2 = 0;
+			apci1564_reset(dev);
+			break;
+		case COMEDI_DIGITAL_TRIG_ENABLE_EDGES:
+			if (devpriv->ctrl != (APCI1564_DI_INT_ENABLE |
+					      APCI1564_DI_INT_OR)) {
+				/* switching to 'OR' mode */
+				devpriv->ctrl = APCI1564_DI_INT_ENABLE |
+						APCI1564_DI_INT_OR;
+				/* wipe old channels */
+				devpriv->mode1 = 0;
+				devpriv->mode2 = 0;
+			} else {
+				/* preserve unspecified channels */
+				devpriv->mode1 &= oldmask;
+				devpriv->mode2 &= oldmask;
+			}
+			/* configure specified channels */
+			devpriv->mode1 |= data[4] << shift;
+			devpriv->mode2 |= data[5] << shift;
+			break;
+		case COMEDI_DIGITAL_TRIG_ENABLE_LEVELS:
+			if (devpriv->ctrl != (APCI1564_DI_INT_ENABLE |
+					      APCI1564_DI_INT_AND)) {
+				/* switching to 'AND' mode */
+				devpriv->ctrl = APCI1564_DI_INT_ENABLE |
+						APCI1564_DI_INT_AND;
+				/* wipe old channels */
+				devpriv->mode1 = 0;
+				devpriv->mode2 = 0;
+			} else {
+				/* preserve unspecified channels */
+				devpriv->mode1 &= oldmask;
+				devpriv->mode2 &= oldmask;
+			}
+			/* configure specified channels */
+			devpriv->mode1 |= data[4] << shift;
+			devpriv->mode2 |= data[5] << shift;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+	return insn->n;
+}
 
-	devpriv->do_int_type = 0;
+static int apci1564_cos_insn_bits(struct comedi_device *dev,
+				  struct comedi_subdevice *s,
+				  struct comedi_insn *insn,
+				  unsigned int *data)
+{
+	data[1] = s->state;
 
-	/* Disable the input interrupts and reset status register */
-	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_IRQ_REG);
-	inl(devpriv->amcc_iobase + APCI1564_DI_INT_STATUS_REG);
-	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE1_REG);
-	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE2_REG);
+	return 0;
+}
 
-	/* Reset the output channels and disable interrupts */
-	outl(0x0, devpriv->amcc_iobase + APCI1564_DO_REG);
-	outl(0x0, devpriv->amcc_iobase + APCI1564_DO_INT_CTRL_REG);
+static int apci1564_cos_cmdtest(struct comedi_device *dev,
+				struct comedi_subdevice *s,
+				struct comedi_cmd *cmd)
+{
+	int err = 0;
 
-	/* Reset the watchdog registers */
-	addi_watchdog_reset(devpriv->amcc_iobase + APCI1564_WDOG_REG);
+	/* Step 1 : check if triggers are trivially valid */
 
-	/* Reset the timer registers */
-	outl(0x0, devpriv->amcc_iobase + APCI1564_TIMER_CTRL_REG);
-	outl(0x0, devpriv->amcc_iobase + APCI1564_TIMER_RELOAD_REG);
+	err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW);
+	err |= cfc_check_trigger_src(&cmd->scan_begin_src, TRIG_EXT);
+	err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_FOLLOW);
+	err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
+	err |= cfc_check_trigger_src(&cmd->stop_src, TRIG_NONE);
 
-	/* Reset the counter registers */
-	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER1));
-	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER2));
-	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER3));
-	outl(0x0, dev->iobase + APCI1564_TCW_CTRL_REG(APCI1564_COUNTER4));
+	if (err)
+		return 1;
+
+	/* Step 2a : make sure trigger sources are unique */
+	/* Step 2b : and mutually compatible */
+
+	if (err)
+		return 2;
+
+	/* Step 3: check if arguments are trivially valid */
+
+	err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
+	err |= cfc_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
+	err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0);
+	err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
+	err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
+
+	if (err)
+		return 3;
+
+	/* step 4: ignored */
+
+	if (err)
+		return 4;
+
+	return 0;
+}
+
+/*
+ * Change-Of-State (COS) 'do_cmd' operation
+ *
+ * Enable the COS interrupt as configured by apci1564_cos_insn_config().
+ */
+static int apci1564_cos_cmd(struct comedi_device *dev,
+			    struct comedi_subdevice *s)
+{
+	struct apci1564_private *devpriv = dev->private;
+
+	if (!devpriv->ctrl) {
+		dev_warn(dev->class_dev,
+			"Interrupts disabled due to mode configuration!\n");
+		return -EINVAL;
+	}
+
+	outl(devpriv->mode1, devpriv->amcc_iobase + APCI1564_DI_INT_MODE1_REG);
+	outl(devpriv->mode2, devpriv->amcc_iobase + APCI1564_DI_INT_MODE2_REG);
+	outl(devpriv->ctrl, devpriv->amcc_iobase + APCI1564_DI_IRQ_REG);
+
+	return 0;
+}
+
+static int apci1564_cos_cancel(struct comedi_device *dev,
+			       struct comedi_subdevice *s)
+{
+	struct apci1564_private *devpriv = dev->private;
+
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_IRQ_REG);
+	inl(devpriv->amcc_iobase + APCI1564_DI_INT_STATUS_REG);
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE1_REG);
+	outl(0x0, devpriv->amcc_iobase + APCI1564_DI_INT_MODE2_REG);
 
 	return 0;
 }
@@ -113,7 +301,7 @@ static int apci1564_auto_attach(struct comedi_device *dev,
 			dev->irq = pcidev->irq;
 	}
 
-	ret = comedi_alloc_subdevices(dev, 3);
+	ret = comedi_alloc_subdevices(dev, 4);
 	if (ret)
 		return ret;
 
@@ -125,7 +313,6 @@ static int apci1564_auto_attach(struct comedi_device *dev,
 	s->maxdata = 1;
 	s->len_chanlist = 32;
 	s->range_table = &range_digital;
-	s->insn_config = apci1564_di_config;
 	s->insn_bits = apci1564_di_insn_bits;
 
 	/*  Allocate and Initialise DO Subdevice Structures */
@@ -152,6 +339,25 @@ static int apci1564_auto_attach(struct comedi_device *dev,
 	s->insn_read = apci1564_timer_read;
 	s->insn_config = apci1564_timer_config;
 
+	/* Change-Of-State (COS) interrupt subdevice */
+	s = &dev->subdevices[3];
+	if (dev->irq) {
+		dev->read_subdev = s;
+		s->type = COMEDI_SUBD_DI;
+		s->subdev_flags = SDF_READABLE | SDF_CMD_READ;
+		s->n_chan = 1;
+		s->maxdata = 1;
+		s->range_table = &range_digital;
+		s->len_chanlist = 1;
+		s->insn_config = apci1564_cos_insn_config;
+		s->insn_bits = apci1564_cos_insn_bits;
+		s->do_cmdtest = apci1564_cos_cmdtest;
+		s->do_cmd = apci1564_cos_cmd;
+		s->cancel = apci1564_cos_cancel;
+	} else {
+		s->type = COMEDI_SUBD_UNUSED;
+	}
+
 	return 0;
 }