staging: comedi: pcl816: 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.
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

@@ -181,6 +181,7 @@ config COMEDI_PCL812
 config COMEDI_PCL816
 	tristate "Advantech PCL-814 and PCL-816 ISA card support"
 	select COMEDI_ISADMA if ISA_DMA_API
+	select COMEDI_8254
 	---help---
 	  Enable support for Advantech PCL-814 and PCL-816 ISA cards
 

drivers/staging/comedi/drivers/pcl816.c

@@ -42,7 +42,7 @@ Configuration Options:
 
 #include "comedi_isadma.h"
 #include "comedi_fc.h"
-#include "8253.h"
+#include "comedi_8254.h"
 
 /*
  * Register I/O map
@@ -116,31 +116,10 @@ static const struct pcl816_board boardtypes[] = {
 struct pcl816_private {
 	struct comedi_isadma *dma;
 	unsigned int ai_poll_ptr;	/*  how many sampes transfer poll */
-	unsigned int divisor1;
-	unsigned int divisor2;
 	unsigned int ai_cmd_running:1;
 	unsigned int ai_cmd_canceled:1;
 };
 
-static void pcl816_start_pacer(struct comedi_device *dev, bool load_counters)
-{
-	struct pcl816_private *devpriv = dev->private;
-	unsigned long timer_base = dev->iobase + PCL816_TIMER_BASE;
-
-	i8254_set_mode(timer_base, 0, 0, I8254_MODE1 | I8254_BINARY);
-	i8254_write(timer_base, 0, 0, 0x00ff);
-	udelay(1);
-
-	i8254_set_mode(timer_base, 0, 2, I8254_MODE2 | I8254_BINARY);
-	i8254_set_mode(timer_base, 0, 1, I8254_MODE2 | I8254_BINARY);
-	udelay(1);
-
-	if (load_counters) {
-		i8254_write(timer_base, 0, 2, devpriv->divisor2);
-		i8254_write(timer_base, 0, 1, devpriv->divisor1);
-	}
-}
-
 static void pcl816_ai_setup_dma(struct comedi_device *dev,
 				struct comedi_subdevice *s,
 				unsigned int unread_samples)
@@ -367,9 +346,7 @@ static int check_channel_list(struct comedi_device *dev,
 static int pcl816_ai_cmdtest(struct comedi_device *dev,
 			     struct comedi_subdevice *s, struct comedi_cmd *cmd)
 {
-	struct pcl816_private *devpriv = dev->private;
 	int err = 0;
-	unsigned int arg;
 
 	/* Step 1 : check if triggers are trivially valid */
 
@@ -416,11 +393,9 @@ static int pcl816_ai_cmdtest(struct comedi_device *dev,
 
 	/* step 4: fix up any arguments */
 	if (cmd->convert_src == TRIG_TIMER) {
-		arg = cmd->convert_arg;
-		i8253_cascade_ns_to_timer(I8254_OSC_BASE_10MHZ,
-					  &devpriv->divisor1,
-					  &devpriv->divisor2,
-					  &arg, cmd->flags);
+		unsigned int arg = cmd->convert_arg;
+
+		comedi_8254_cascade_ns_to_timer(dev->pacer, &arg, cmd->flags);
 		err |= cfc_check_trigger_arg_is(&cmd->convert_arg, arg);
 	}
 
@@ -450,8 +425,6 @@ static int pcl816_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 	if (devpriv->ai_cmd_running)
 		return -EBUSY;
 
-	pcl816_start_pacer(dev, false);
-
 	seglen = check_channel_list(dev, s, cmd->chanlist, cmd->chanlist_len);
 	if (seglen < 1)
 		return -EINVAL;
@@ -466,7 +439,11 @@ static int pcl816_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 	dma->cur_dma = 0;
 	pcl816_ai_setup_dma(dev, s, 0);
 
-	pcl816_start_pacer(dev, true);
+	comedi_8254_set_mode(dev->pacer, 0, I8254_MODE1 | I8254_BINARY);
+	comedi_8254_write(dev->pacer, 0, 0x0ff);
+	udelay(1);
+	comedi_8254_update_divisors(dev->pacer);
+	comedi_8254_pacer_enable(dev->pacer, 1, 2, true);
 
 	ctrl = PCL816_CTRL_INTEN | PCL816_CTRL_DMAEN | PCL816_CTRL_DMASRC_SLOT0;
 	if (cmd->convert_src == TRIG_TIMER)
@@ -525,11 +502,7 @@ static int pcl816_ai_cancel(struct comedi_device *dev,
 	outb(PCL816_CTRL_DISABLE_TRIG, dev->iobase + PCL816_CTRL_REG);
 	pcl816_ai_clear_eoc(dev);
 
-	/* Stop pacer */
-	i8254_set_mode(dev->iobase + PCL816_TIMER_BASE, 0,
-			2, I8254_MODE0 | I8254_BINARY);
-	i8254_set_mode(dev->iobase + PCL816_TIMER_BASE, 0,
-			1, I8254_MODE0 | I8254_BINARY);
+	comedi_8254_pacer_enable(dev->pacer, 1, 2, false);
 
 	devpriv->ai_cmd_running = 0;
 	devpriv->ai_cmd_canceled = 1;
@@ -596,17 +569,10 @@ static int pcl816_do_insn_bits(struct comedi_device *dev,
 
 static void pcl816_reset(struct comedi_device *dev)
 {
-	unsigned long timer_base = dev->iobase + PCL816_TIMER_BASE;
-
 	outb(PCL816_CTRL_DISABLE_TRIG, dev->iobase + PCL816_CTRL_REG);
 	pcl816_ai_set_chan_range(dev, 0, 0);
 	pcl816_ai_clear_eoc(dev);
 
-	/* Stop pacer */
-	i8254_set_mode(timer_base, 0, 2, I8254_MODE0 | I8254_BINARY);
-	i8254_set_mode(timer_base, 0, 1, I8254_MODE0 | I8254_BINARY);
-	i8254_set_mode(timer_base, 0, 0, I8254_MODE0 | I8254_BINARY);
-
 	/* set all digital outputs low */
 	outb(0, dev->iobase + PCL816_DO_DI_LSB_REG);
 	outb(0, dev->iobase + PCL816_DO_DI_MSB_REG);
@@ -662,6 +628,11 @@ static int pcl816_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	/* an IRQ and DMA are required to support async commands */
 	pcl816_alloc_irq_and_dma(dev, it);
 
+	dev->pacer = comedi_8254_init(dev->iobase + PCL816_TIMER_BASE,
+				      I8254_OSC_BASE_10MHZ, I8254_IO8, 0);
+	if (!dev->pacer)
+		return -ENOMEM;
+
 	ret = comedi_alloc_subdevices(dev, 4);
 	if (ret)
 		return ret;