From 362b646062b2073bd5c38efb42171d86e4f717e6 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Fri, 4 Nov 2011 03:33:46 +0100 Subject: ACPI: Export FADT pm_profile integer value to userspace There are a lot userspace approaches to detect the usage of the platform (laptop, workstation, server, ...) and adjust kernel tunables accordingly (io/process scheduler, power management, ...). These approaches need constant maintaining and are ugly to implement (detect PCMCIA controller -> laptop, does not work on recent systems anymore, ...) On ACPI systems there is an easy and reliable way (if implemented in BIOS and most recent platforms have this value set). -> export it to userspace. Signed-off-by: Thomas Renninger Acked-by: Rafael J. Wysocki Signed-off-by: Len Brown --- drivers/acpi/sysfs.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index c538d0ef10ff..9f66181c814e 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -706,11 +706,23 @@ static void __exit interrupt_stats_exit(void) return; } +static ssize_t +acpi_show_profile(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", acpi_gbl_FADT.preferred_profile); +} + +static const struct device_attribute pm_profile_attr = + __ATTR(pm_profile, S_IRUGO, acpi_show_profile, NULL); + int __init acpi_sysfs_init(void) { int result; result = acpi_tables_sysfs_init(); - + if (result) + return result; + result = sysfs_create_file(acpi_kobj, &pm_profile_attr.attr); return result; } -- cgit v1.2.3