From 0774c2b5c1e0025cb016393d8552171c0ec55c39 Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Mon, 3 Dec 2012 18:15:40 +0000 Subject: [PATCH] staging: comedi: addi_apci_2032: interrupt safety change Put the hardware into a safe state before enabling the interrupt. In the interrupt routine, check the device has been fully configured by checking `dev->attached`. In particular, `dev->read_subdev` could be NULL early on and although the hardware's status register should indicate no interrupt has occurred (since it's been put into a safe state), it's better not to rely on it. Signed-off-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/addi_apci_2032.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/addi_apci_2032.c b/drivers/staging/comedi/drivers/addi_apci_2032.c index 8f8d3e95fc78..3b5e1d74d129 100644 --- a/drivers/staging/comedi/drivers/addi_apci_2032.c +++ b/drivers/staging/comedi/drivers/addi_apci_2032.c @@ -237,6 +237,9 @@ static irqreturn_t apci2032_interrupt(int irq, void *d) struct comedi_subdevice *s = dev->read_subdev; unsigned int val; + if (!dev->attached) + return IRQ_NONE; + /* Check if VCC OR CC interrupt has occurred */ val = inl(dev->iobase + APCI2032_STATUS_REG) & APCI2032_STATUS_IRQ; if (!val) @@ -281,6 +284,7 @@ static int apci2032_auto_attach(struct comedi_device *dev, if (ret) return ret; dev->iobase = pci_resource_start(pcidev, 1); + apci2032_reset(dev); if (pcidev->irq > 0) { ret = request_irq(pcidev->irq, apci2032_interrupt, @@ -329,7 +333,6 @@ static int apci2032_auto_attach(struct comedi_device *dev, s->type = COMEDI_SUBD_UNUSED; } - apci2032_reset(dev); return 0; } -- 2.30.2