staging: comedi: ni_labpc_common: convert driver to use the comedi_8254 module

This driver uses an 8254 timer to generate the pacer clock used for analog
input data conversion. Convert it to use the comedi_8254 module to provide
support for the 8254 timer.

The hardware actually has two 8254 devices. Timer B0 is the master for timed
conversions, timer B1 sets the scan pacing, and tmer A0 sets the conversion
pacing.

For the conversion, dev->pacer is used for the "B" timers and a new private
data member, dev->counter, is used for the "A" timers. All the divisor values
are stored in the dev->pacer.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/Kconfig

@@ -1292,6 +1292,7 @@ config COMEDI_ISADMA
 
 config COMEDI_NI_LABPC
 	tristate
+	select COMEDI_8254
 	select COMEDI_8255
 
 config COMEDI_NI_LABPC_ISADMA

drivers/staging/comedi/drivers/ni_labpc.c

@@ -105,6 +105,7 @@ static int labpc_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 static void labpc_detach(struct comedi_device *dev)
 {
 	labpc_free_dma_chan(dev);
+	labpc_common_detach(dev);
 	comedi_legacy_detach(dev);
 }
 

drivers/staging/comedi/drivers/ni_labpc.h

@@ -36,6 +36,7 @@ struct labpc_boardinfo {
 
 struct labpc_private {
 	struct comedi_isadma *dma;
+	struct comedi_8254 *counter;
 
 	/*  number of data points left to be taken */
 	unsigned long long count;
@@ -49,20 +50,6 @@ struct labpc_private {
 	/*  store last read of board status registers */
 	unsigned int stat1;
 	unsigned int stat2;
-	/*
-	 * value to load into board's counter a0 (conversion pacing) for timed
-	 * conversions
-	 */
-	unsigned int divisor_a0;
-	/*
-	 * value to load into board's counter b0 (master) for timed conversions
-	 */
-	unsigned int divisor_b0;
-	/*
-	 * value to load into board's counter b1 (scan pacing) for timed
-	 * conversions
-	 */
-	unsigned int divisor_b1;
 
 	/* we are using dma/fifo-half-full/etc. */
 	enum transfer_type current_transfer;
@@ -77,5 +64,6 @@ struct labpc_private {
 
 int labpc_common_attach(struct comedi_device *dev,
 			unsigned int irq, unsigned long isr_flags);
+void labpc_common_detach(struct comedi_device *dev);
 
 #endif /* _NI_LABPC_H */

drivers/staging/comedi/drivers/ni_labpc_common.c

@@ -20,10 +20,11 @@
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/delay.h>
+#include <linux/slab.h>
 
 #include "../comedidev.h"
 
-#include "8253.h"
+#include "comedi_8254.h"
 #include "8255.h"
 #include "comedi_fc.h"
 #include "ni_labpc.h"
@@ -108,32 +109,6 @@ static void labpc_writeb(struct comedi_device *dev,
 	writeb(byte, dev->mmio + reg);
 }
 
-static void labpc_counter_load(struct comedi_device *dev,
-			       unsigned long reg,
-			       unsigned int counter_number,
-			       unsigned int count,
-			       unsigned int mode)
-{
-	if (dev->mmio) {
-		i8254_mm_set_mode(dev->mmio + reg, 0, counter_number, mode);
-		i8254_mm_write(dev->mmio + reg, 0, counter_number, count);
-	} else {
-		i8254_set_mode(dev->iobase + reg, 0, counter_number, mode);
-		i8254_write(dev->iobase + reg, 0, counter_number, count);
-	}
-}
-
-static void labpc_counter_set_mode(struct comedi_device *dev,
-				   unsigned long reg,
-				   unsigned int counter_number,
-				   unsigned int mode)
-{
-	if (dev->mmio)
-		i8254_mm_set_mode(dev->mmio + reg, 0, counter_number, mode);
-	else
-		i8254_set_mode(dev->iobase + reg, 0, counter_number, mode);
-}
-
 static int labpc_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
 {
 	struct labpc_private *devpriv = dev->private;
@@ -284,7 +259,7 @@ static int labpc_ai_insn_read(struct comedi_device *dev,
 	devpriv->write_byte(dev, devpriv->cmd4, CMD4_REG);
 
 	/* initialize pacer counter to prevent any problems */
-	labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 0, I8254_MODE2);
+	comedi_8254_set_mode(devpriv->counter, 0, I8254_MODE2 | I8254_BINARY);
 
 	labpc_clear_adc_fifo(dev);
 
@@ -367,83 +342,79 @@ static void labpc_set_ai_scan_period(struct comedi_cmd *cmd,
 static void labpc_adc_timing(struct comedi_device *dev, struct comedi_cmd *cmd,
 			     enum scan_mode mode)
 {
-	struct labpc_private *devpriv = dev->private;
+	struct comedi_8254 *pacer = dev->pacer;
+	unsigned int convert_period = labpc_ai_convert_period(cmd, mode);
+	unsigned int scan_period = labpc_ai_scan_period(cmd, mode);
 	unsigned int base_period;
-	unsigned int scan_period;
-	unsigned int convert_period;
 
 	/*
-	 * if both convert and scan triggers are TRIG_TIMER, then they
-	 * both rely on counter b0
+	 * If both convert and scan triggers are TRIG_TIMER, then they
+	 * both rely on counter b0. If only one TRIG_TIMER is used, we
+	 * can use the generic cascaded timing functions.
 	 */
-	convert_period = labpc_ai_convert_period(cmd, mode);
-	scan_period = labpc_ai_scan_period(cmd, mode);
 	if (convert_period && scan_period) {
 		/*
-		 * pick the lowest b0 divisor value we can (for maximum input
+		 * pick the lowest divisor value we can (for maximum input
 		 * clock speed on convert and scan counters)
 		 */
-		devpriv->divisor_b0 = (scan_period - 1) /
-		    (I8254_OSC_BASE_2MHZ * 0x10000) + 1;
+		pacer->next_div1 = (scan_period - 1) /
+				   (pacer->osc_base * I8254_MAX_COUNT) + 1;
 
-		cfc_check_trigger_arg_min(&devpriv->divisor_b0, 2);
-		cfc_check_trigger_arg_max(&devpriv->divisor_b0, 0x10000);
+		cfc_check_trigger_arg_min(&pacer->next_div1, 2);
+		cfc_check_trigger_arg_max(&pacer->next_div1, I8254_MAX_COUNT);
 
-		base_period = I8254_OSC_BASE_2MHZ * devpriv->divisor_b0;
+		base_period = pacer->osc_base * pacer->next_div1;
 
 		/*  set a0 for conversion frequency and b1 for scan frequency */
 		switch (cmd->flags & CMDF_ROUND_MASK) {
 		default:
 		case CMDF_ROUND_NEAREST:
-			devpriv->divisor_a0 = DIV_ROUND_CLOSEST(convert_period,
-								base_period);
-			devpriv->divisor_b1 = DIV_ROUND_CLOSEST(scan_period,
-								base_period);
+			pacer->next_div = DIV_ROUND_CLOSEST(convert_period,
+							    base_period);
+			pacer->next_div2 = DIV_ROUND_CLOSEST(scan_period,
+							     base_period);
 			break;
 		case CMDF_ROUND_UP:
-			devpriv->divisor_a0 = DIV_ROUND_UP(convert_period,
-							   base_period);
-			devpriv->divisor_b1 = DIV_ROUND_UP(scan_period,
-							   base_period);
+			pacer->next_div = DIV_ROUND_UP(convert_period,
+						       base_period);
+			pacer->next_div2 = DIV_ROUND_UP(scan_period,
+							base_period);
 			break;
 		case CMDF_ROUND_DOWN:
-			devpriv->divisor_a0 = convert_period / base_period;
-			devpriv->divisor_b1 = scan_period / base_period;
+			pacer->next_div = convert_period / base_period;
+			pacer->next_div2 = scan_period / base_period;
 			break;
 		}
 		/*  make sure a0 and b1 values are acceptable */
-		cfc_check_trigger_arg_min(&devpriv->divisor_a0, 2);
-		cfc_check_trigger_arg_max(&devpriv->divisor_a0, 0x10000);
-		cfc_check_trigger_arg_min(&devpriv->divisor_b1, 2);
-		cfc_check_trigger_arg_max(&devpriv->divisor_b1, 0x10000);
+		cfc_check_trigger_arg_min(&pacer->next_div, 2);
+		cfc_check_trigger_arg_max(&pacer->next_div, I8254_MAX_COUNT);
+		cfc_check_trigger_arg_min(&pacer->next_div2, 2);
+		cfc_check_trigger_arg_max(&pacer->next_div2, I8254_MAX_COUNT);
+
 		/*  write corrected timings to command */
 		labpc_set_ai_convert_period(cmd, mode,
-					    base_period * devpriv->divisor_a0);
+					    base_period * pacer->next_div);
 		labpc_set_ai_scan_period(cmd, mode,
-					 base_period * devpriv->divisor_b1);
-		/*
-		 * if only one TRIG_TIMER is used, we can employ the generic
-		 * cascaded timing functions
-		 */
+					 base_period * pacer->next_div2);
 	} else if (scan_period) {
 		/*
 		 * calculate cascaded counter values
 		 * that give desired scan timing
+		 * (pacer->next_div2 / pacer->next_div1)
 		 */
-		i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ,
-					  &devpriv->divisor_b1,
-					  &devpriv->divisor_b0,
-					  &scan_period, cmd->flags);
+		comedi_8254_cascade_ns_to_timer(pacer, &scan_period,
+						cmd->flags);
 		labpc_set_ai_scan_period(cmd, mode, scan_period);
 	} else if (convert_period) {
 		/*
 		 * calculate cascaded counter values
 		 * that give desired conversion timing
+		 * (pacer->next_div / pacer->next_div1)
 		 */
-		i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ,
-					  &devpriv->divisor_a0,
-					  &devpriv->divisor_b0,
-					  &convert_period, cmd->flags);
+		comedi_8254_cascade_ns_to_timer(pacer, &convert_period,
+						cmd->flags);
+		/* transfer div2 value so correct timer gets updated */
+		pacer->next_div = pacer->next_div2;
 		labpc_set_ai_convert_period(cmd, mode, convert_period);
 	}
 }
@@ -667,11 +638,12 @@ static int labpc_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 		 * load counter a1 with count of 3
 		 * (pc+ manual says this is minimum allowed) using mode 0
 		 */
-		labpc_counter_load(dev, COUNTER_A_BASE_REG,
-				   1, 3, I8254_MODE0);
+		comedi_8254_load(devpriv->counter, 1,
+				 3, I8254_MODE0 | I8254_BINARY);
 	} else	{
 		/* just put counter a1 in mode 0 to set its output low */
-		labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 1, I8254_MODE0);
+		comedi_8254_set_mode(devpriv->counter, 1,
+				     I8254_MODE0 | I8254_BINARY);
 	}
 
 	/* figure out what method we will use to transfer data */
@@ -712,27 +684,24 @@ static int labpc_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 
 	if (cmd->convert_src == TRIG_TIMER ||
 	    cmd->scan_begin_src == TRIG_TIMER) {
-		/*  set up pacing */
-		labpc_adc_timing(dev, cmd, mode);
-		/*  load counter b0 in mode 3 */
-		labpc_counter_load(dev, COUNTER_B_BASE_REG,
-				   0, devpriv->divisor_b0, I8254_MODE3);
-	}
-	/*  set up conversion pacing */
-	if (labpc_ai_convert_period(cmd, mode)) {
-		/*  load counter a0 in mode 2 */
-		labpc_counter_load(dev, COUNTER_A_BASE_REG,
-				   0, devpriv->divisor_a0, I8254_MODE2);
-	} else {
-		/* initialize pacer counter to prevent any problems */
-		labpc_counter_set_mode(dev, COUNTER_A_BASE_REG, 0, I8254_MODE2);
-	}
+		struct comedi_8254 *pacer = dev->pacer;
+		struct comedi_8254 *counter = devpriv->counter;
+
+		comedi_8254_update_divisors(pacer);
+
+		/* set up pacing */
+		comedi_8254_load(pacer, 0, pacer->divisor1,
+				 I8254_MODE3 | I8254_BINARY);
 
-	/*  set up scan pacing */
-	if (labpc_ai_scan_period(cmd, mode)) {
-		/*  load counter b1 in mode 2 */
-		labpc_counter_load(dev, COUNTER_B_BASE_REG,
-				   1, devpriv->divisor_b1, I8254_MODE2);
+		/* set up conversion pacing */
+		comedi_8254_set_mode(counter, 0, I8254_MODE2 | I8254_BINARY);
+		if (labpc_ai_convert_period(cmd, mode))
+			comedi_8254_write(counter, 0, pacer->divisor);
+
+		/* set up scan pacing */
+		if (labpc_ai_scan_period(cmd, mode))
+			comedi_8254_load(pacer, 1, pacer->divisor2,
+					 I8254_MODE2 | I8254_BINARY);
 	}
 
 	labpc_clear_adc_fifo(dev);
@@ -1237,6 +1206,26 @@ int labpc_common_attach(struct comedi_device *dev,
 			dev->irq = irq;
 	}
 
+	if (dev->mmio) {
+		dev->pacer = comedi_8254_mm_init(dev->mmio + COUNTER_B_BASE_REG,
+						 I8254_OSC_BASE_2MHZ,
+						 I8254_IO8, 0);
+		devpriv->counter = comedi_8254_mm_init(dev->mmio +
+						       COUNTER_A_BASE_REG,
+						       I8254_OSC_BASE_2MHZ,
+						       I8254_IO8, 0);
+	} else {
+		dev->pacer = comedi_8254_init(dev->iobase + COUNTER_B_BASE_REG,
+					      I8254_OSC_BASE_2MHZ,
+					      I8254_IO8, 0);
+		devpriv->counter = comedi_8254_init(dev->iobase +
+						    COUNTER_A_BASE_REG,
+						    I8254_OSC_BASE_2MHZ,
+						    I8254_IO8, 0);
+	}
+	if (!dev->pacer || !devpriv->counter)
+		return -ENOMEM;
+
 	ret = comedi_alloc_subdevices(dev, 5);
 	if (ret)
 		return ret;
@@ -1333,6 +1322,15 @@ int labpc_common_attach(struct comedi_device *dev,
 }
 EXPORT_SYMBOL_GPL(labpc_common_attach);
 
+void labpc_common_detach(struct comedi_device *dev)
+{
+	struct labpc_private *devpriv = dev->private;
+
+	if (devpriv)
+		kfree(devpriv->counter);
+}
+EXPORT_SYMBOL_GPL(labpc_common_detach);
+
 static int __init labpc_common_init(void)
 {
 	return 0;

drivers/staging/comedi/drivers/ni_labpc_cs.c

@@ -68,8 +68,8 @@ static const struct labpc_boardinfo labpc_cs_boards[] = {
 	},
 };
 
-static int labpc_auto_attach(struct comedi_device *dev,
-			     unsigned long context)
+static int labpc_cs_auto_attach(struct comedi_device *dev,
+				unsigned long context)
 {
 	struct pcmcia_device *link = comedi_to_pcmcia_dev(dev);
 	int ret;
@@ -90,11 +90,17 @@ static int labpc_auto_attach(struct comedi_device *dev,
 	return labpc_common_attach(dev, link->irq, IRQF_SHARED);
 }
 
+static void labpc_cs_detach(struct comedi_device *dev)
+{
+	labpc_common_detach(dev);
+	comedi_pcmcia_disable(dev);
+}
+
 static struct comedi_driver driver_labpc_cs = {
 	.driver_name	= "ni_labpc_cs",
 	.module		= THIS_MODULE,
-	.auto_attach	= labpc_auto_attach,
-	.detach		= comedi_pcmcia_disable,
+	.auto_attach	= labpc_cs_auto_attach,
+	.detach		= labpc_cs_detach,
 };
 
 static int labpc_cs_attach(struct pcmcia_device *link)

drivers/staging/comedi/drivers/ni_labpc_pci.c

@@ -103,11 +103,17 @@ static int labpc_pci_auto_attach(struct comedi_device *dev,
 	return labpc_common_attach(dev, pcidev->irq, IRQF_SHARED);
 }
 
+static void labpc_pci_detach(struct comedi_device *dev)
+{
+	labpc_common_detach(dev);
+	comedi_pci_detach(dev);
+}
+
 static struct comedi_driver labpc_pci_comedi_driver = {
 	.driver_name	= "labpc_pci",
 	.module		= THIS_MODULE,
 	.auto_attach	= labpc_pci_auto_attach,
-	.detach		= comedi_pci_detach,
+	.detach		= labpc_pci_detach,
 };
 
 static const struct pci_device_id labpc_pci_table[] = {