Commit ca6f998c authored May 01, 2019 by Pierre-Louis Bossart Committed by Rafael J. Wysocki May 10, 2019

ACPI: bus: change _ADR representation to 64 bits



Standards such as the MIPI DisCo for SoundWire 1.0 specification
assume the _ADR field is 64 bits.

_ADR is defined as an "Integer" represented as 64 bits since ACPI 2.0
released in 2002. The low levels already use _ADR as 64 bits, e.g. in
struct acpi_device_info.

This patch bumps the representation used for sysfs to 64 bits. To
avoid any compatibility/ABI issues, the printf format is only extended
to 16 characters when the actual _ADR value exceeds the 32 bit
maximum.

Example with a SoundWire device, the results show the complete
vendorID and linkID which were omitted before:

Before:
$ more /sys/bus/acpi/devices/device\:38/adr
0x5d070000
After:
$ more /sys/bus/acpi/devices/device\:38/adr
0x000010025d070000

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
[ rjw: Replace 0xFFFFFFFF with U32_MAX, clean up subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent 59df1c2b

drivers/acpi/device_sysfs.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -428,8 +428,10 @@ static ssize_t acpi_device_adr_show(struct device *dev,
		{
		struct acpi_device *acpi_dev = to_acpi_device(dev);

		return sprintf(buf, "0x%08x\n",
		(unsigned int)(acpi_dev->pnp.bus_address));
		if (acpi_dev->pnp.bus_address > U32_MAX)
		return sprintf(buf, "0x%016llx\n", acpi_dev->pnp.bus_address);
		else
		return sprintf(buf, "0x%08llx\n", acpi_dev->pnp.bus_address);
		}
		static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);

include/acpi/acpi_bus.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -230,7 +230,7 @@ struct acpi_device_dir {
		/* Plug and Play */

		typedef char acpi_bus_id[8];
		typedef unsigned long acpi_bus_address;
		typedef u64 acpi_bus_address;
		typedef char acpi_device_name[40];
		typedef char acpi_device_class[20];

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