pcmcia: setup IRQ to be used by PCMCIA drivers at card insert
authorDominik Brodowski <linux@dominikbrodowski.net>
Thu, 8 Apr 2010 18:33:16 +0000 (20:33 +0200)
committerDominik Brodowski <linux@dominikbrodowski.net>
Mon, 10 May 2010 08:23:11 +0000 (10:23 +0200)
Setup the IRQ to be used by PCMCIA drivers already during the device
registration stage, making use of a new function pcmcia_setup_irq().
This will allow us to get rid of quite a lot of indirection in the
future.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
drivers/pcmcia/cs_internal.h
drivers/pcmcia/ds.c
drivers/pcmcia/pcmcia_resource.c
include/pcmcia/ds.h

index f95864c..74d91c8 100644 (file)
@@ -149,6 +149,8 @@ extern struct resource *pcmcia_find_mem_region(u_long base,
                                               int low,
                                               struct pcmcia_socket *s);
 
+void pcmcia_cleanup_irq(struct pcmcia_socket *s);
+int pcmcia_setup_irq(struct pcmcia_device *p_dev);
 
 /* cistpl.c */
 extern struct bin_attribute pccard_cis_attr;
index 041eee4..5fd2948 100644 (file)
@@ -546,26 +546,32 @@ struct pcmcia_device *pcmcia_device_add(struct pcmcia_socket *s, unsigned int fu
                        p_dev->function_config = tmp_dev->function_config;
                        p_dev->io = tmp_dev->io;
                        p_dev->irq = tmp_dev->irq;
+                       p_dev->irq_v = tmp_dev->irq_v;
                        kref_get(&p_dev->function_config->ref);
                }
 
        /* Add to the list in pcmcia_bus_socket */
        list_add(&p_dev->socket_device_list, &s->devices_list);
 
-       mutex_unlock(&s->ops_mutex);
+       if (pcmcia_setup_irq(p_dev))
+               dev_warn(&p_dev->dev,
+                       "IRQ setup failed -- device might not work\n");
 
        if (!p_dev->function_config) {
                dev_dbg(&p_dev->dev, "creating config_t\n");
                p_dev->function_config = kzalloc(sizeof(struct config_t),
                                                 GFP_KERNEL);
-               if (!p_dev->function_config)
+               if (!p_dev->function_config) {
+                       mutex_unlock(&s->ops_mutex);
                        goto err_unreg;
+               }
                kref_init(&p_dev->function_config->ref);
        }
+       mutex_unlock(&s->ops_mutex);
 
        dev_printk(KERN_NOTICE, &p_dev->dev,
-                  "pcmcia: registering new device %s\n",
-                  p_dev->devname);
+                  "pcmcia: registering new device %s (IRQ: %d)\n",
+                  p_dev->devname, p_dev->irq_v);
 
        pcmcia_device_query(p_dev);
 
@@ -1258,6 +1264,7 @@ static int ds_event(struct pcmcia_socket *skt, event_t event, int priority)
                handle_event(skt, event);
                mutex_lock(&s->ops_mutex);
                destroy_cis_cache(s);
+               pcmcia_cleanup_irq(s);
                mutex_unlock(&s->ops_mutex);
                break;
 
index ba82cb3..ff9c0bc 100644 (file)
@@ -23,6 +23,8 @@
 #include <linux/netdevice.h>
 #include <linux/slab.h>
 
+#include <asm/irq.h>
+
 #include <pcmcia/cs_types.h>
 #include <pcmcia/ss.h>
 #include <pcmcia/cs.h>
@@ -38,12 +40,6 @@ static int io_speed;
 module_param(io_speed, int, 0444);
 
 
-#ifdef CONFIG_PCMCIA_PROBE
-#include <asm/irq.h>
-/* mask of IRQs already reserved by other cards, we should avoid using them */
-static u8 pcmcia_used_irq[NR_IRQS];
-#endif
-
 static int pcmcia_adjust_io_region(struct resource *res, unsigned long start,
                                   unsigned long end, struct pcmcia_socket *s)
 {
@@ -440,15 +436,11 @@ static int pcmcia_release_irq(struct pcmcia_device *p_dev, irq_req_t *req)
        }
        if (--s->irq.Config == 0) {
                c->state &= ~CONFIG_IRQ_REQ;
-               s->irq.AssignedIRQ = 0;
        }
 
        if (req->Handler)
                free_irq(req->AssignedIRQ, p_dev->priv);
 
-#ifdef CONFIG_PCMCIA_PROBE
-       pcmcia_used_irq[req->AssignedIRQ]--;
-#endif
        ret = 0;
 
 out:
@@ -699,26 +691,14 @@ EXPORT_SYMBOL(pcmcia_request_io);
 /** pcmcia_request_irq
  *
  * Request_irq() reserves an irq for this client.
- *
- * Also, since Linux only reserves irq's when they are actually
- * hooked, we don't guarantee that an irq will still be available
- * when the configuration is locked.  Now that I think about it,
- * there might be a way to fix this using a dummy handler.
  */
 
-#ifdef CONFIG_PCMCIA_PROBE
-static irqreturn_t test_action(int cpl, void *dev_id)
-{
-       return IRQ_NONE;
-}
-#endif
-
 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 = -EINVAL, irq = 0;
-       int type;
+       int ret = -EINVAL, irq = p_dev->irq_v;
+       int type = IRQF_SHARED;
 
        mutex_lock(&s->ops_mutex);
 
@@ -736,63 +716,20 @@ int pcmcia_request_irq(struct pcmcia_device *p_dev, irq_req_t *req)
                goto out;
        }
 
-       /* Decide what type of interrupt we are registering */
-       type = 0;
-       if (s->functions > 1)           /* All of this ought to be handled higher up */
-               type = IRQF_SHARED;
-       else if (req->Attributes & IRQ_TYPE_DYNAMIC_SHARING)
-               type = IRQF_SHARED;
-       else
-               printk(KERN_WARNING "pcmcia: Driver needs updating to support IRQ sharing.\n");
-
-       /* If the interrupt is already assigned, it must be the same */
-       if (s->irq.AssignedIRQ != 0)
-               irq = s->irq.AssignedIRQ;
-
-#ifdef CONFIG_PCMCIA_PROBE
        if (!irq) {
-               int try;
-               u32 mask = s->irq_mask;
-               void *data = p_dev; /* something unique to this device */
-
-               for (try = 0; try < 64; try++) {
-                       irq = try % 32;
-
-                       /* marked as available by driver, and not blocked by userspace? */
-                       if (!((mask >> irq) & 1))
-                               continue;
-
-                       /* avoid an IRQ which is already used by a PCMCIA card */
-                       if ((try < 32) && pcmcia_used_irq[irq])
-                               continue;
-
-                       /* register the correct driver, if possible, of check whether
-                        * registering a dummy handle works, i.e. if the IRQ isn't
-                        * marked as used by the kernel resource management core */
-                       ret = request_irq(irq,
-                                         (req->Handler) ? req->Handler : test_action,
-                                         type,
-                                         p_dev->devname,
-                                         (req->Handler) ? p_dev->priv : data);
-                       if (!ret) {
-                               if (!req->Handler)
-                                       free_irq(irq, data);
-                               break;
-                       }
-               }
+               dev_dbg(&s->dev, "no IRQ available\n");
+               goto out;
        }
-#endif
-       /* only assign PCI irq if no IRQ already assigned */
-       if (ret && !s->irq.AssignedIRQ) {
-               if (!s->pci_irq) {
-                       dev_printk(KERN_INFO, &s->dev, "no IRQ found\n");
-                       goto out;
-               }
-               type = IRQF_SHARED;
-               irq = s->pci_irq;
+
+       if (!(req->Attributes & IRQ_TYPE_DYNAMIC_SHARING)) {
+               req->Attributes |= IRQ_TYPE_DYNAMIC_SHARING;
+               dev_printk(KERN_WARNING, &p_dev->dev, "pcmcia: "
+                       "request for exclusive IRQ could not be fulfilled.\n");
+               dev_printk(KERN_WARNING, &p_dev->dev, "pcmcia: the driver "
+                       "needs updating to supported shared IRQ lines.\n");
        }
 
-       if (ret && req->Handler) {
+       if (req->Handler) {
                ret = request_irq(irq, req->Handler, type,
                                  p_dev->devname, p_dev->priv);
                if (ret) {
@@ -802,25 +739,13 @@ int pcmcia_request_irq(struct pcmcia_device *p_dev, irq_req_t *req)
                }
        }
 
-       /* Make sure the fact the request type was overridden is passed back */
-       if (type == IRQF_SHARED && !(req->Attributes & IRQ_TYPE_DYNAMIC_SHARING)) {
-               req->Attributes |= IRQ_TYPE_DYNAMIC_SHARING;
-               dev_printk(KERN_WARNING, &p_dev->dev, "pcmcia: "
-                       "request for exclusive IRQ could not be fulfilled.\n");
-               dev_printk(KERN_WARNING, &p_dev->dev, "pcmcia: the driver "
-                       "needs updating to supported shared IRQ lines.\n");
-       }
        c->irq.Attributes = req->Attributes;
-       s->irq.AssignedIRQ = req->AssignedIRQ = irq;
+       req->AssignedIRQ = irq;
        s->irq.Config++;
 
        c->state |= CONFIG_IRQ_REQ;
        p_dev->_irq = 1;
 
-#ifdef CONFIG_PCMCIA_PROBE
-       pcmcia_used_irq[irq]++;
-#endif
-
        ret = 0;
 out:
        mutex_unlock(&s->ops_mutex);
@@ -829,6 +754,115 @@ out:
 EXPORT_SYMBOL(pcmcia_request_irq);
 
 
+#ifdef CONFIG_PCMCIA_PROBE
+
+/* mask of IRQs already reserved by other cards, we should avoid using them */
+static u8 pcmcia_used_irq[NR_IRQS];
+
+static irqreturn_t test_action(int cpl, void *dev_id)
+{
+       return IRQ_NONE;
+}
+
+/**
+ * pcmcia_setup_isa_irq() - determine whether an ISA IRQ can be used
+ * @p_dev - the associated PCMCIA device
+ *
+ * locking note: must be called with ops_mutex locked.
+ */
+static int pcmcia_setup_isa_irq(struct pcmcia_device *p_dev, int type)
+{
+       struct pcmcia_socket *s = p_dev->socket;
+       unsigned int try, irq;
+       u32 mask = s->irq_mask;
+       int ret = -ENODEV;
+
+       for (try = 0; try < 64; try++) {
+               irq = try % 32;
+
+               /* marked as available by driver, not blocked by userspace? */
+               if (!((mask >> irq) & 1))
+                       continue;
+
+               /* avoid an IRQ which is already used by another PCMCIA card */
+               if ((try < 32) && pcmcia_used_irq[irq])
+                       continue;
+
+               /* register the correct driver, if possible, to check whether
+                * registering a dummy handle works, i.e. if the IRQ isn't
+                * marked as used by the kernel resource management core */
+               ret = request_irq(irq, test_action, type, p_dev->devname,
+                                 p_dev);
+               if (!ret) {
+                       free_irq(irq, p_dev);
+                       p_dev->irq_v = s->irq.AssignedIRQ = irq;
+                       pcmcia_used_irq[irq]++;
+                       break;
+               }
+       }
+
+       return ret;
+}
+
+void pcmcia_cleanup_irq(struct pcmcia_socket *s)
+{
+       pcmcia_used_irq[s->irq.AssignedIRQ]--;
+       s->irq.AssignedIRQ = 0;
+}
+
+#else /* CONFIG_PCMCIA_PROBE */
+
+static int pcmcia_setup_isa_irq(struct pcmcia_device *p_dev, int type)
+{
+       return -EINVAL;
+}
+
+void pcmcia_cleanup_irq(struct pcmcia_socket *s)
+{
+       s->irq.AssignedIRQ = 0;
+       return;
+}
+
+#endif  /* CONFIG_PCMCIA_PROBE */
+
+
+/**
+ * pcmcia_setup_irq() - determine IRQ to be used for device
+ * @p_dev - the associated PCMCIA device
+ *
+ * locking note: must be called with ops_mutex locked.
+ */
+int pcmcia_setup_irq(struct pcmcia_device *p_dev)
+{
+       struct pcmcia_socket *s = p_dev->socket;
+
+       if (p_dev->irq_v)
+               return 0;
+
+       /* already assigned? */
+       if (s->irq.AssignedIRQ) {
+               p_dev->irq_v = s->irq.AssignedIRQ;
+               return 0;
+       }
+
+       /* prefer an exclusive ISA irq */
+       if (!pcmcia_setup_isa_irq(p_dev, 0))
+               return 0;
+
+       /* but accept a shared ISA irq */
+       if (!pcmcia_setup_isa_irq(p_dev, IRQF_SHARED))
+               return 0;
+
+       /* but use the PCI irq otherwise */
+       if (s->pci_irq) {
+               p_dev->irq_v = s->irq.AssignedIRQ = s->pci_irq;
+               return 0;
+       }
+
+       return -EINVAL;
+}
+
+
 /** pcmcia_request_window
  *
  * Request_window() establishes a mapping between card memory space
index aab3c13..52ebe75 100644 (file)
@@ -95,6 +95,9 @@ struct pcmcia_device {
        config_req_t            conf;
        window_handle_t         win;
 
+       /* device setup */
+       unsigned int            irq_v; /* do not use directly yet */
+
        /* Is the device suspended? */
        u16                     suspended:1;