[PATCH] staging: comedi: refactor pcmda12 driver to remove forward declarations
H Hartley Sweeten
hartleys at visionengravers.com
Fri Apr 27 22:44:02 UTC 2012
Move the module_init/module_exit routines and the associated
struct comedi_driver and other variables to the end of the source.
This is more typical of how other drivers are written and removes
the need for the forward declarations.
Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
Cc: Ian Abbott <abbotti at mev.co.uk>
Cc: Mori Hess <fmhess at users.sourceforge.net>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
diff --git a/drivers/staging/comedi/drivers/pcmda12.c b/drivers/staging/comedi/drivers/pcmda12.c
index 0e9ffa2..4846d98 100644
--- a/drivers/staging/comedi/drivers/pcmda12.c
+++ b/drivers/staging/comedi/drivers/pcmda12.c
@@ -80,12 +80,6 @@ static const struct comedi_lrange pcmda12_ranges = {
}
};
-static const struct pcmda12_board pcmda12_boards[] = {
- {
- .name = "pcmda12",
- },
-};
-
/*
* Useful for shorthand access to the particular board structure
*/
@@ -99,57 +93,77 @@ struct pcmda12_private {
#define devpriv ((struct pcmda12_private *)(dev->private))
-/*
- * The struct comedi_driver structure tells the Comedi core module
- * which functions to call to configure/deconfigure (attach/detach)
- * the board, and also about the kernel module that contains
- * the device code.
- */
-static int pcmda12_attach(struct comedi_device *dev,
- struct comedi_devconfig *it);
-static int pcmda12_detach(struct comedi_device *dev);
+static void zero_chans(struct comedi_device *dev)
+{ /* sets up an
+ ASIC chip to defaults */
+ int i;
+ for (i = 0; i < CHANS; ++i) {
+/* /\* do this as one instruction?? *\/ */
+/* outw(0, LSB_PORT(chan)); */
+ outb(0, LSB_PORT(i));
+ outb(0, MSB_PORT(i));
+ }
+ inb(LSB_PORT(0)); /* update chans. */
+}
-static void zero_chans(struct comedi_device *dev);
+static int ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
+ struct comedi_insn *insn, unsigned int *data)
+{
+ int i;
+ int chan = CR_CHAN(insn->chanspec);
-static struct comedi_driver driver = {
- .driver_name = "pcmda12",
- .module = THIS_MODULE,
- .attach = pcmda12_attach,
- .detach = pcmda12_detach,
-/* It is not necessary to implement the following members if you are
- * writing a driver for a ISA PnP or PCI card */
- /* Most drivers will support multiple types of boards by
- * having an array of board structures. These were defined
- * in pcmda12_boards[] above. Note that the element 'name'
- * was first in the structure -- Comedi uses this fact to
- * extract the name of the board without knowing any details
- * about the structure except for its length.
- * When a device is attached (by comedi_config), the name
- * of the device is given to Comedi, and Comedi tries to
- * match it by going through the list of board names. If
- * there is a match, the address of the pointer is put
- * into dev->board_ptr and driver->attach() is called.
- *
- * Note that these are not necessary if you can determine
- * the type of board in software. ISA PnP, PCI, and PCMCIA
- * devices are such boards.
- */
- .board_name = &pcmda12_boards[0].name,
- .offset = sizeof(struct pcmda12_board),
- .num_names = ARRAY_SIZE(pcmda12_boards),
-};
+ /* Writing a list of values to an AO channel is probably not
+ * very useful, but that's how the interface is defined. */
+ for (i = 0; i < insn->n; ++i) {
-static int ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
- struct comedi_insn *insn, unsigned int *data);
+/* /\* do this as one instruction?? *\/ */
+/* outw(data[i], LSB_PORT(chan)); */
+
+ /* Need to do this as two instructions due to 8-bit bus?? */
+ /* first, load the low byte */
+ outb(LSB(data[i]), LSB_PORT(chan));
+ /* next, write the high byte */
+ outb(MSB(data[i]), MSB_PORT(chan));
+
+ /* save shadow register */
+ devpriv->ao_readback[chan] = data[i];
+
+ if (!devpriv->simultaneous_xfer_mode)
+ inb(LSB_PORT(chan));
+ }
+
+ /* return the number of samples written */
+ return i;
+}
+
+/* AO subdevices should have a read insn as well as a write insn.
+
+ Usually this means copying a value stored in devpriv->ao_readback.
+ However, since this driver supports simultaneous xfer then sometimes
+ this function actually accomplishes work.
+
+ Simultaneaous xfer mode is accomplished by loading ALL the values
+ you want for AO in all the channels, then READing off one of the AO
+ registers to initiate the instantaneous simultaneous update of all
+ DAC outputs, which makes all AO channels update simultaneously.
+ This is useful for some control applications, I would imagine.
+*/
static int ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
- struct comedi_insn *insn, unsigned int *data);
+ struct comedi_insn *insn, unsigned int *data)
+{
+ int i;
+ int chan = CR_CHAN(insn->chanspec);
+
+ for (i = 0; i < insn->n; i++) {
+ if (devpriv->simultaneous_xfer_mode)
+ inb(LSB_PORT(chan));
+ /* read back shadow register */
+ data[i] = devpriv->ao_readback[chan];
+ }
+
+ return i;
+}
-/*
- * Attach is called by the Comedi core to configure the driver
- * for a particular board. If you specified a board_name array
- * in the driver structure, dev->board_ptr contains that
- * address.
- */
static int pcmda12_attach(struct comedi_device *dev,
struct comedi_devconfig *it)
{
@@ -213,14 +227,6 @@ static int pcmda12_attach(struct comedi_device *dev,
return 1;
}
-/*
- * _detach is called to deconfigure a device. It should deallocate
- * resources.
- * This function is also called when _attach() fails, so it should be
- * careful not to release resources that were not necessarily
- * allocated by _attach(). dev->private and dev->subdevices are
- * deallocated automatically by the core.
- */
static int pcmda12_detach(struct comedi_device *dev)
{
printk(KERN_INFO
@@ -230,92 +236,32 @@ static int pcmda12_detach(struct comedi_device *dev)
return 0;
}
-static void zero_chans(struct comedi_device *dev)
-{ /* sets up an
- ASIC chip to defaults */
- int i;
- for (i = 0; i < CHANS; ++i) {
-/* /\* do this as one instruction?? *\/ */
-/* outw(0, LSB_PORT(chan)); */
- outb(0, LSB_PORT(i));
- outb(0, MSB_PORT(i));
- }
- inb(LSB_PORT(0)); /* update chans. */
-}
-
-static int ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
- struct comedi_insn *insn, unsigned int *data)
-{
- int i;
- int chan = CR_CHAN(insn->chanspec);
-
- /* Writing a list of values to an AO channel is probably not
- * very useful, but that's how the interface is defined. */
- for (i = 0; i < insn->n; ++i) {
-
-/* /\* do this as one instruction?? *\/ */
-/* outw(data[i], LSB_PORT(chan)); */
-
- /* Need to do this as two instructions due to 8-bit bus?? */
- /* first, load the low byte */
- outb(LSB(data[i]), LSB_PORT(chan));
- /* next, write the high byte */
- outb(MSB(data[i]), MSB_PORT(chan));
-
- /* save shadow register */
- devpriv->ao_readback[chan] = data[i];
-
- if (!devpriv->simultaneous_xfer_mode)
- inb(LSB_PORT(chan));
- }
-
- /* return the number of samples written */
- return i;
-}
-
-/* AO subdevices should have a read insn as well as a write insn.
-
- Usually this means copying a value stored in devpriv->ao_readback.
- However, since this driver supports simultaneous xfer then sometimes
- this function actually accomplishes work.
-
- Simultaneaous xfer mode is accomplished by loading ALL the values
- you want for AO in all the channels, then READing off one of the AO
- registers to initiate the instantaneous simultaneous update of all
- DAC outputs, which makes all AO channels update simultaneously.
- This is useful for some control applications, I would imagine.
-*/
-static int ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
- struct comedi_insn *insn, unsigned int *data)
-{
- int i;
- int chan = CR_CHAN(insn->chanspec);
-
- for (i = 0; i < insn->n; i++) {
- if (devpriv->simultaneous_xfer_mode)
- inb(LSB_PORT(chan));
- /* read back shadow register */
- data[i] = devpriv->ao_readback[chan];
- }
+static const struct pcmda12_board pcmda12_boards[] = {
+ {
+ .name = "pcmda12",
+ },
+};
- return i;
-}
+static struct comedi_driver driver = {
+ .driver_name = "pcmda12",
+ .module = THIS_MODULE,
+ .attach = pcmda12_attach,
+ .detach = pcmda12_detach,
+ .board_name = &pcmda12_boards[0].name,
+ .offset = sizeof(struct pcmda12_board),
+ .num_names = ARRAY_SIZE(pcmda12_boards),
+};
-/*
- * A convenient macro that defines init_module() and cleanup_module(),
- * as necessary.
- */
static int __init driver_init_module(void)
{
return comedi_driver_register(&driver);
}
+module_init(driver_init_module);
static void __exit driver_cleanup_module(void)
{
comedi_driver_unregister(&driver);
}
-
-module_init(driver_init_module);
module_exit(driver_cleanup_module);
MODULE_AUTHOR("Comedi http://www.comedi.org");
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