-----Original Message----- From: Pierre-Louis Bossart [mailto:pierre-louis.bossart@linux.intel.com] Sent: Wednesday, May 1, 2019 5:53 AM To: alsa-devel@alsa-project.org Cc: linux-kernel@vger.kernel.org; tiwai@suse.de; broonie@kernel.org; vkoul@kernel.org; gregkh@linuxfoundation.org; liam.r.girdwood@linux.intel.com; jank@cadence.com; joe@perches.com; srinivas.kandagatla@linaro.org; Pierre-Louis Bossart <pierre- louis.bossart@linux.intel.com>; Rafael J. Wysocki rjw@rjwysocki.net; Len Brown lenb@kernel.org; Moore, Robert robert.moore@intel.com; Schmauss, Erik erik.schmauss@intel.com; open list:ACPI <linux- acpi@vger.kernel.org>; open list:ACPI COMPONENT ARCHITECTURE (ACPICA) devel@acpica.org Subject: [PATCH v2] ACPI / device_sysfs: 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.
[Moore, Robert]
Just to be precise: since acpi 2.0 the integer width is either 32 bits or 64 bits, depending on the version number of the DSDT (1-->32, 2 or greater --> 64).
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>
v2: only use 64 bits when required to avoid compatibility issues (feedback from Vinod and Rafael)
drivers/acpi/device_sysfs.c | 6 ++++-- include/acpi/acpi_bus.h | 2 +- 2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c index 8940054d6250..7dda0ee05cd1 100644 --- a/drivers/acpi/device_sysfs.c +++ b/drivers/acpi/device_sysfs.c @@ -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 > 0xFFFFFFFF)
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);
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index f7981751ac77..9075e28ea60a 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -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];
-- 2.17.1