diff options
| author | Myron Stowe <myron.stowe@hp.com> | 2010-10-21 14:23:59 -0600 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2010-10-24 23:26:23 -0400 |
| commit | 29718521237a1b1607ea05b49243100ea2044337 (patch) | |
| tree | 69608fa74248415a6055f0b48753cf54b63043b3 | |
| parent | 620242ae8c3d9c0b1a77451744fb2d855d1e7342 (diff) | |
ACPI: Add interfaces for ioremapping/iounmapping ACPI registers
Add remapping and unmapping interfaces for ACPI registers that are
backed by memory mapped I/O (MMIO). These interfaces, along with
the MMIO remapping list, enable accesses of such registers from within
interrupt context.
ACPI Generic Address Structure (GAS) reference (ACPI's fixed/generic
hardware registers use the GAS format):
ACPI Specification, Revision 4.0, Section 5.2.3.1, "Generic Address
Structure".
Signed-off-by: Myron Stowe <myron.stowe@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
| -rw-r--r-- | drivers/acpi/osl.c | 38 | ||||
| -rw-r--r-- | include/linux/acpi.h | 3 |
2 files changed, 41 insertions, 0 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index bd72129e35f..fc6c5d21c3e 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -372,6 +372,44 @@ void __init early_acpi_os_unmap_memory(void __iomem *virt, acpi_size size) __acpi_unmap_table(virt, size); } +int acpi_os_map_generic_address(struct acpi_generic_address *addr) +{ + void __iomem *virt; + + if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) + return 0; + + if (!addr->address || !addr->bit_width) + return -EINVAL; + + virt = acpi_os_map_memory(addr->address, addr->bit_width / 8); + if (!virt) + return -EIO; + + return 0; +} +EXPORT_SYMBOL_GPL(acpi_os_map_generic_address); + +void acpi_os_unmap_generic_address(struct acpi_generic_address *addr) +{ + void __iomem *virt; + unsigned long flags; + acpi_size size = addr->bit_width / 8; + + if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) + return; + + if (!addr->address || !addr->bit_width) + return; + + spin_lock_irqsave(&acpi_ioremap_lock, flags); + virt = acpi_map_vaddr_lookup(addr->address, size); + spin_unlock_irqrestore(&acpi_ioremap_lock, flags); + + acpi_os_unmap_memory(virt, size); +} +EXPORT_SYMBOL_GPL(acpi_os_unmap_generic_address); + #ifdef ACPI_FUTURE_USAGE acpi_status acpi_os_get_physical_address(void *virt, acpi_physical_address * phys) diff --git a/include/linux/acpi.h b/include/linux/acpi.h index c227757feb0..7774e6d8fdd 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -308,6 +308,9 @@ extern acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req); extern void acpi_early_init(void); +int acpi_os_map_generic_address(struct acpi_generic_address *addr); +void acpi_os_unmap_generic_address(struct acpi_generic_address *addr); + #else /* !CONFIG_ACPI */ #define acpi_disabled 1 |