The paged registers in the asic need to be spinlock protected to
ensure that the page is not changed while writing to the registers.
Introduce a helper function to make sure the spinlock is used.
Use the new helper in pcmmio_reset(). This is one of the places where
the spinlock is not used.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/pcmmio.c | 49 ++++++++++++++++++++-------------
1 file changed, 30 insertions(+), 19 deletions(-)
diff --git a/drivers/staging/comedi/drivers/pcmmio.c b/drivers/staging/comedi/drivers/pcmmio.c
index 3f1fb9b..873fcf3 100644
--- a/drivers/staging/comedi/drivers/pcmmio.c
+++ b/drivers/staging/comedi/drivers/pcmmio.c
@@ -260,6 +260,28 @@ struct pcmmio_private {
unsigned int ao_readback[8];
};
+static void pcmmio_dio_write(struct comedi_device *dev, unsigned int val,
+ int page, int port)
+{
+ struct pcmmio_private *devpriv = dev->private;
+ unsigned long iobase = dev->iobase;
+ unsigned long flags;
+
+ spin_lock_irqsave(&devpriv->pagelock, flags);
+ if (page == 0) {
+ /* Port registers are valid for any page */
+ outb(val & 0xff, iobase + PCMMIO_PORT_REG(port + 0));
+ outb((val >> 8) & 0xff, iobase + PCMMIO_PORT_REG(port + 1));
+ outb((val >> 16) & 0xff, iobase + PCMMIO_PORT_REG(port + 2));
+ } else {
+ outb(PCMMIO_PAGE(page), iobase + PCMMIO_PAGE_LOCK_REG);
+ outb(val & 0xff, iobase + PCMMIO_PAGE_REG(0));
+ outb((val >> 8) & 0xff, iobase + PCMMIO_PAGE_REG(1));
+ outb((val >> 16) & 0xff, iobase + PCMMIO_PAGE_REG(2));
+ }
+ spin_unlock_irqrestore(&devpriv->pagelock, flags);
+}
+
/* DIO devices are slightly special. Although it is possible to
* implement the insn_read/insn_write interface, it is much more
* useful to applications if you implement the insn_bits interface.
@@ -355,25 +377,14 @@ static void switch_page(struct comedi_device *dev, int page)
static void pcmmio_reset(struct comedi_device *dev)
{
- int port, page;
-
- switch_page(dev, 0); /* switch back to page 0 */
-
- /* first, clear all the DIO port bits */
- for (port = 0; port < PORTS_PER_ASIC; ++port)
- outb(0, dev->iobase + PCMMIO_PORT_REG(port));
-
- /* Next, clear all the paged registers for each page */
- for (page = 1; page < NUM_PAGES; ++page) {
- int reg;
- /* now clear all the paged registers */
- switch_page(dev, page);
- for (reg = 0; reg < NUM_PAGED_REGS; ++reg)
- outb(0, dev->iobase + PCMMIO_PAGE_REG(reg));
- }
-
- /* switch back to default page 0 */
- switch_page(dev, 0);
+ /* Clear all the DIO port bits */
+ pcmmio_dio_write(dev, 0, 0, 0);
+ pcmmio_dio_write(dev, 0, 0, 3);
+
+ /* Clear all the paged registers */
+ pcmmio_dio_write(dev, 0, PCMMIO_PAGE_POL, 0);
+ pcmmio_dio_write(dev, 0, PCMMIO_PAGE_ENAB, 0);
+ pcmmio_dio_write(dev, 0, PCMMIO_PAGE_INT_ID, 0);
}
static void pcmmio_stop_intr(struct comedi_device *dev,
--
1.8.4.4
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