ACPI: Introduce acpi_os_get_iomem()

Introduce function acpi_os_get_iomem() that may be used by its callers
to get a reference to an ACPI iomap.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 5389f9f..52ca872 100644 (file)
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -285,6 +285,22 @@ acpi_map_vaddr_lookup(acpi_physical_address phys, unsigned int size)
        return NULL;
 }
 
+void __iomem *acpi_os_get_iomem(acpi_physical_address phys, unsigned int size)
+{
+       struct acpi_ioremap *map;
+       void __iomem *virt = NULL;
+
+       mutex_lock(&acpi_ioremap_lock);
+       map = acpi_map_lookup(phys, size);
+       if (map) {
+               virt = map->virt + (phys - map->phys);
+               map->refcount++;
+       }
+       mutex_unlock(&acpi_ioremap_lock);
+       return virt;
+}
+EXPORT_SYMBOL_GPL(acpi_os_get_iomem);
+
 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
 static struct acpi_ioremap *
 acpi_map_lookup_virt(void __iomem *virt, acpi_size size)

diff --git a/include/linux/acpi_io.h b/include/linux/acpi_io.h
index 28a3ae2..4afd710 100644 (file)
--- a/include/linux/acpi_io.h
+++ b/include/linux/acpi_io.h
@@ -10,4 +10,6 @@ static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
        return ioremap_cache(phys, size);
 }
 
+void __iomem *acpi_os_get_iomem(acpi_physical_address phys, unsigned int size);
+
 #endif