From a2ff95e018f1d2bc816f3078d5110a655e355f18 Mon Sep 17 00:00:00 2001 From: Mark Pearson Date: Tue, 29 Dec 2020 19:18:26 -0500 Subject: ACPI: platform: Add platform profile support This is the initial implementation of the platform-profile feature. It provides the details discussed and outlined in the sysfs-platform_profile document. Many modern systems have the ability to modify the operating profile to control aspects like fan speed, temperature and power levels. This module provides a common sysfs interface that platform modules can register against to control their individual profile options. Signed-off-by: Mark Pearson Reviewed-by: Hans de Goede [ rjw: Use full words in enum values names ] Signed-off-by: Rafael J. Wysocki --- drivers/acpi/platform_profile.c | 181 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 181 insertions(+) create mode 100644 drivers/acpi/platform_profile.c (limited to 'drivers/acpi/platform_profile.c') diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c new file mode 100644 index 000000000000..91be50a32cc8 --- /dev/null +++ b/drivers/acpi/platform_profile.c @@ -0,0 +1,181 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +/* Platform profile sysfs interface */ + +#include +#include +#include +#include +#include +#include + +static const struct platform_profile_handler *cur_profile; +static DEFINE_MUTEX(profile_lock); + +static const char * const profile_names[] = { + [PLATFORM_PROFILE_LOW_POWER] = "low-power", + [PLATFORM_PROFILE_COOL] = "cool", + [PLATFORM_PROFILE_QUIET] = "quiet", + [PLATFORM_PROFILE_BALANCED] = "balanced", + [PLATFORM_PROFILE_PERFORMANCE] = "performance", +}; +static_assert(ARRAY_SIZE(profile_names) == PLATFORM_PROFILE_LAST); + +static ssize_t platform_profile_choices_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + int len = 0; + int err, i; + + err = mutex_lock_interruptible(&profile_lock); + if (err) + return err; + + if (!cur_profile) { + mutex_unlock(&profile_lock); + return -ENODEV; + } + + for_each_set_bit(i, cur_profile->choices, PLATFORM_PROFILE_LAST) { + if (len == 0) + len += sysfs_emit_at(buf, len, "%s", profile_names[i]); + else + len += sysfs_emit_at(buf, len, " %s", profile_names[i]); + } + len += sysfs_emit_at(buf, len, "\n"); + mutex_unlock(&profile_lock); + return len; +} + +static ssize_t platform_profile_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + enum platform_profile_option profile = PLATFORM_PROFILE_BALANCED; + int err; + + err = mutex_lock_interruptible(&profile_lock); + if (err) + return err; + + if (!cur_profile) { + mutex_unlock(&profile_lock); + return -ENODEV; + } + + err = cur_profile->profile_get(&profile); + mutex_unlock(&profile_lock); + if (err) + return err; + + /* Check that profile is valid index */ + if (WARN_ON((profile < 0) || (profile >= ARRAY_SIZE(profile_names)))) + return -EIO; + + return sysfs_emit(buf, "%s\n", profile_names[profile]); +} + +static ssize_t platform_profile_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int err, i; + + err = mutex_lock_interruptible(&profile_lock); + if (err) + return err; + + if (!cur_profile) { + mutex_unlock(&profile_lock); + return -ENODEV; + } + + /* Scan for a matching profile */ + i = sysfs_match_string(profile_names, buf); + if (i < 0) { + mutex_unlock(&profile_lock); + return -EINVAL; + } + + /* Check that platform supports this profile choice */ + if (!test_bit(i, cur_profile->choices)) { + mutex_unlock(&profile_lock); + return -EOPNOTSUPP; + } + + err = cur_profile->profile_set(i); + mutex_unlock(&profile_lock); + if (err) + return err; + return count; +} + +static DEVICE_ATTR_RO(platform_profile_choices); +static DEVICE_ATTR_RW(platform_profile); + +static struct attribute *platform_profile_attrs[] = { + &dev_attr_platform_profile_choices.attr, + &dev_attr_platform_profile.attr, + NULL +}; + +static const struct attribute_group platform_profile_group = { + .attrs = platform_profile_attrs +}; + +void platform_profile_notify(void) +{ + if (!cur_profile) + return; + sysfs_notify(acpi_kobj, NULL, "platform_profile"); +} +EXPORT_SYMBOL_GPL(platform_profile_notify); + +int platform_profile_register(const struct platform_profile_handler *pprof) +{ + int err; + + mutex_lock(&profile_lock); + /* We can only have one active profile */ + if (cur_profile) { + mutex_unlock(&profile_lock); + return -EEXIST; + } + + /* Sanity check the profile handler field are set */ + if (!pprof || bitmap_empty(pprof->choices, PLATFORM_PROFILE_LAST) || + !pprof->profile_set || !pprof->profile_get) { + mutex_unlock(&profile_lock); + return -EINVAL; + } + + err = sysfs_create_group(acpi_kobj, &platform_profile_group); + if (err) { + mutex_unlock(&profile_lock); + return err; + } + + cur_profile = pprof; + mutex_unlock(&profile_lock); + return 0; +} +EXPORT_SYMBOL_GPL(platform_profile_register); + +int platform_profile_remove(void) +{ + mutex_lock(&profile_lock); + if (!cur_profile) { + mutex_unlock(&profile_lock); + return -ENODEV; + } + + sysfs_remove_group(acpi_kobj, &platform_profile_group); + cur_profile = NULL; + mutex_unlock(&profile_lock); + return 0; +} +EXPORT_SYMBOL_GPL(platform_profile_remove); + +MODULE_AUTHOR("Mark Pearson "); +MODULE_LICENSE("GPL"); -- cgit