kernel: bugfix IRQ release

Interrupt resources are not properly released. Mainly two problems: 1. on IRQ free the driver was using the IRQ number instead of the the component base address. So, the component IRQ handlers were never released 2. on IRQ free, supposing that the first problem was not there, when all component's IRQ handlers were released the PCI IRQ handler (VIC dispatcher) should have released, but it was not. In consequence of this even if the driver was removed an interrupt can be handled by a ghost handler. Signed-off-by: Federico Vaga <federico.vaga@cern.ch>

kernel: bugfix IRQ release
Interrupt resources are not properly released. Mainly two problems: 1. on IRQ free the driver was using the IRQ number instead of the the component base address. So, the component IRQ handlers were never released 2. on IRQ free, supposing that the first problem was not there, when all component's IRQ handlers were released the PCI IRQ handler (VIC dispatcher) should have released, but it was not. In consequence of this even if the driver was removed an interrupt can be handled by a ghost handler. Signed-off-by: Federico Vaga <federico.vaga@cern.ch>
60dc7cd5 · Federico Vaga · c791d5b0 · 60dc7cd5 · 60dc7cd5 · 60dc7cd5
Commit 60dc7cd5 authored Jul 01, 2014 by Federico Vaga
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spec-fmc.c kernel/spec-fmc.c +8 -2

spec-vic.c kernel/spec-vic.c +23 -2

spec.h kernel/spec.h +1 -2

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--- a/kernel/spec-fmc.c
+++ b/kernel/spec-fmc.c
@@ -221,9 +221,15 @@ static int spec_irq_free(struct fmc_device *fmc)
 	struct spec_dev *spec = fmc->carrier_data;

 	if (spec->vic)
-		return spec_vic_irq_free(spec, spec->pdev->irq);
-	else
+		spec_vic_irq_free(spec, fmc->irq);
+
+	/*
+	 * If we were not using the VIC, or we released all the VIC handler, then
+	 * release the PCI IRQ handler
+	 */
+	if (!spec->vic)
 		return spec_shared_irq_free(fmc);
+	return 0;
 }

 /* This is the mapping from virtual GPIO pin numbers to raw gpio numbers */

--- a/kernel/spec-vic.c
+++ b/kernel/spec-vic.c
@@ -99,7 +99,7 @@ static int spec_vic_init(struct spec_dev *spec, struct fmc_device *fmc)
 	return 0;
 }

-void spec_vic_cleanup(struct spec_dev *spec)
+static void spec_vic_cleanup(struct spec_dev *spec)
 {
 	if (!spec->vic)
 		return;
@@ -169,11 +169,26 @@ int spec_vic_irq_request(struct spec_dev *spec, struct fmc_device *fmc,
 		}
 	}

-
 	return -EINVAL;
+}
+
+
+/*
+ * vic_handler_count
+ * It counts how many handlers are registered within the VIC controller
+ */
+static inline int vic_handler_count(struct vic_irq_controller *vic)
+{
+	int i, count;
+
+	for (i = 0, count = 0; i < VIC_MAX_VECTORS; ++i)
+		if (vic->vectors[i].handler)
+			count++;

+	return count;
 }

+
 int spec_vic_irq_free(struct spec_dev *spec, unsigned long id)
 {
 	int i;
@@ -191,6 +206,12 @@ int spec_vic_irq_free(struct spec_dev *spec, unsigned long id)
 		}
 	}

+	/* Clean up the VIC if there are no more handlers */
+	if (!vic_handler_count(spec->vic)) {
+		spec_vic_cleanup(spec);
+		spec->vic = NULL;
+	}
+
 	return 0;
 }


--- a/kernel/spec.h
+++ b/kernel/spec.h
@@ -144,11 +144,10 @@ extern int spec_eeprom_write(struct fmc_device *fmc, uint32_t offset,
 extern int spec_gpio_init(struct fmc_device *fmc);
 extern void spec_gpio_exit(struct fmc_device *fmc);

+/* Functions in spec-vic.c */
 int spec_vic_irq_request(struct spec_dev *spec, struct fmc_device *fmc,
 			 unsigned long id, irq_handler_t handler);
-
 int spec_vic_irq_free(struct spec_dev *spec, unsigned long id);
 irqreturn_t spec_vic_irq_dispatch(struct spec_dev *spec);
-void spec_vic_cleanup(struct spec_dev *spec);

 #endif /* __SPEC_H__ */