[PATCH] pcmcia: warn if driver requests exclusive, but gets a shared IRQ

The patch below cleans up the pcmcia code a bit on the IRQ side (I did
this while debugging the problem just so I could read wtf it was doing),
and also adds a warning and passes back the correct information when a
device asks for exclusive but gets given shared. This at least means the
dmesg dump of a problem triggered by this will have a signature to find.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

drivers/pcmcia/pcmcia_resource.c

@@ -788,6 +788,7 @@ int pcmcia_request_irq(struct pcmcia_device *p_dev, irq_req_t *req)
 	struct pcmcia_socket *s = p_dev->socket;
 	config_t *c;
 	int ret = CS_IN_USE, irq = 0;
+	int type;
 
 	if (!(s->state & SOCKET_PRESENT))
 		return CS_NO_CARD;
@@ -797,6 +798,13 @@ int pcmcia_request_irq(struct pcmcia_device *p_dev, irq_req_t *req)
 	if (c->state & CONFIG_IRQ_REQ)
 		return CS_IN_USE;
 
+	/* Decide what type of interrupt we are registering */
+	type = 0;
+	if (s->functions > 1)		/* All of this ought to be handled higher up */
+		type = SA_SHIRQ;
+	if (req->Attributes & IRQ_TYPE_DYNAMIC_SHARING)
+		type = SA_SHIRQ;
+
 #ifdef CONFIG_PCMCIA_PROBE
 	if (s->irq.AssignedIRQ != 0) {
 		/* If the interrupt is already assigned, it must be the same */
@@ -822,9 +830,7 @@ int pcmcia_request_irq(struct pcmcia_device *p_dev, irq_req_t *req)
 			 * marked as used by the kernel resource management core */
 			ret = request_irq(irq,
 					  (req->Attributes & IRQ_HANDLE_PRESENT) ? req->Handler : test_action,
-					  ((req->Attributes & IRQ_TYPE_DYNAMIC_SHARING) ||
-					   (s->functions > 1) ||
-					   (irq == s->pci_irq)) ? SA_SHIRQ : 0,
+					  type,
 					  p_dev->devname,
 					  (req->Attributes & IRQ_HANDLE_PRESENT) ? req->Instance : data);
 			if (!ret) {
@@ -839,18 +845,21 @@ int pcmcia_request_irq(struct pcmcia_device *p_dev, irq_req_t *req)
 	if (ret && !s->irq.AssignedIRQ) {
 		if (!s->pci_irq)
 			return ret;
+		type = SA_SHIRQ;
 		irq = s->pci_irq;
 	}
 
-	if (ret && req->Attributes & IRQ_HANDLE_PRESENT) {
-		if (request_irq(irq, req->Handler,
-				((req->Attributes & IRQ_TYPE_DYNAMIC_SHARING) ||
-				 (s->functions > 1) ||
-				 (irq == s->pci_irq)) ? SA_SHIRQ : 0,
-				p_dev->devname, req->Instance))
+	if (ret && (req->Attributes & IRQ_HANDLE_PRESENT)) {
+		if (request_irq(irq, req->Handler, type,  p_dev->devname, req->Instance))
 			return CS_IN_USE;
 	}
 
+	/* Make sure the fact the request type was overridden is passed back */
+	if (type == SA_SHIRQ && !(req->Attributes & IRQ_TYPE_DYNAMIC_SHARING)) {
+		req->Attributes |= IRQ_TYPE_DYNAMIC_SHARING;
+		printk(KERN_WARNING "pcmcia: request for exclusive IRQ could not be fulfilled.\n");
+		printk(KERN_WARNING "pcmcia: the driver needs updating to supported shared IRQ lines.\n");
+	}
 	c->irq.Attributes = req->Attributes;
 	s->irq.AssignedIRQ = req->AssignedIRQ = irq;
 	s->irq.Config++;