[PATCH 3/3] PNP: Handle IORESOURCE_BITS in resource allocation

[Witold Szczeponik <Witold.Szczeponik@gmx.net>]

The patch copies the flags masked by IORESOURCE_BITS from a resource's
template.  This is necessary because the resource settings require proper
IORESOURCE_BITS which are not known during the definition of these
resources using the "/sys/bus/pnp/*/*/resources" interface.  (In fact,
they should not be set by the user as the resource templates define the
proper settings.)

If the patch is not applied, the resource flags are not initialized properly 
and obscure messages in the kernel log have been seen ("invalid flags").  

The patch is applied against Linux 3.3.x.


Signed-off-by: Witold Szczeponik <Witold.Szczeponik@gmx.net>


Index: linux/drivers/pnp/manager.c
===================================================================
--- linux.orig/drivers/pnp/manager.c
+++ linux/drivers/pnp/manager.c
@@ -18,11 +18,27 @@
 
 DEFINE_MUTEX(pnp_res_mutex);
 
+static struct resource *pnp_find_resource(struct pnp_dev *dev,
+					  unsigned char rule,
+					  unsigned long type,
+					  unsigned int bar)
+{
+	struct resource *res = pnp_get_resource(dev, type, bar);
+
+	/* when the resource already exists, set its resource bits from rule */
+	if (res) {
+		res->flags &= ~IORESOURCE_BITS;
+		res->flags |= rule & IORESOURCE_BITS;
+	}
+
+	return res;
+}
+
 static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
 {
 	struct resource *res, local_res;
 
-	res = pnp_get_resource(dev, IORESOURCE_IO, idx);
+	res = pnp_find_resource(dev, rule->flags, IORESOURCE_IO, idx);
 	if (res) {
 		pnp_dbg(&dev->dev, "  io %d already set to %#llx-%#llx "
 			"flags %#lx\n", idx, (unsigned long long) res->start,
@@ -65,7 +81,7 @@ static int pnp_assign_mem(struct pnp_dev
 {
 	struct resource *res, local_res;
 
-	res = pnp_get_resource(dev, IORESOURCE_MEM, idx);
+	res = pnp_find_resource(dev, rule->flags, IORESOURCE_MEM, idx);
 	if (res) {
 		pnp_dbg(&dev->dev, "  mem %d already set to %#llx-%#llx "
 			"flags %#lx\n", idx, (unsigned long long) res->start,
@@ -78,6 +94,7 @@ static int pnp_assign_mem(struct pnp_dev
 	res->start = 0;
 	res->end = 0;
 
+	/* ??? rule->flags restricted to 8 bits, all tests bogus ??? */
 	if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
 		res->flags |= IORESOURCE_READONLY;
 	if (rule->flags & IORESOURCE_MEM_CACHEABLE)
@@ -123,7 +140,7 @@ static int pnp_assign_irq(struct pnp_dev
 		5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
 	};
 
-	res = pnp_get_resource(dev, IORESOURCE_IRQ, idx);
+	res = pnp_find_resource(dev, rule->flags, IORESOURCE_IRQ, idx);
 	if (res) {
 		pnp_dbg(&dev->dev, "  irq %d already set to %d flags %#lx\n",
 			idx, (int) res->start, res->flags);
@@ -182,7 +199,7 @@ static int pnp_assign_dma(struct pnp_dev
 		1, 3, 5, 6, 7, 0, 2, 4
 	};
 
-	res = pnp_get_resource(dev, IORESOURCE_DMA, idx);
+	res = pnp_find_resource(dev, rule->flags, IORESOURCE_DMA, idx);
 	if (res) {
 		pnp_dbg(&dev->dev, "  dma %d already set to %d flags %#lx\n",
 			idx, (int) res->start, res->flags);