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ACPI: bus: change _ADR representation to 64 bits

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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>
This commit is contained in:
Pierre-Louis Bossart 2019-05-01 07:53:22 -05:00 committed by Rafael J. Wysocki
parent 59df1c2bde
commit ca6f998cf9
2 changed files with 5 additions and 3 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

6
drivers/acpi/device_sysfs.c
View file

@ -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);

2
include/acpi/acpi_bus.h
View file

@ -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];