diff options
Diffstat (limited to 'drivers/acpi/device_sysfs.c')
| -rw-r--r-- | drivers/acpi/device_sysfs.c | 521 |
1 files changed, 521 insertions, 0 deletions
diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c new file mode 100644 index 000000000..4ab4582e5 --- /dev/null +++ b/drivers/acpi/device_sysfs.c @@ -0,0 +1,521 @@ +/* + * drivers/acpi/device_sysfs.c - ACPI device sysfs attributes and modalias. + * + * Copyright (C) 2015, Intel Corp. + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/export.h> +#include <linux/nls.h> + +#include "internal.h" + +/** + * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent + * @acpi_dev: ACPI device object. + * @modalias: Buffer to print into. + * @size: Size of the buffer. + * + * Creates hid/cid(s) string needed for modalias and uevent + * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get: + * char *modalias: "acpi:IBM0001:ACPI0001" + * Return: 0: no _HID and no _CID + * -EINVAL: output error + * -ENOMEM: output is truncated +*/ +static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias, + int size) +{ + int len; + int count; + struct acpi_hardware_id *id; + + /* + * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should + * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the + * device's list. + */ + count = 0; + list_for_each_entry(id, &acpi_dev->pnp.ids, list) + if (strcmp(id->id, ACPI_DT_NAMESPACE_HID)) + count++; + + if (!count) + return 0; + + len = snprintf(modalias, size, "acpi:"); + if (len <= 0) + return len; + + size -= len; + + list_for_each_entry(id, &acpi_dev->pnp.ids, list) { + if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID)) + continue; + + count = snprintf(&modalias[len], size, "%s:", id->id); + if (count < 0) + return -EINVAL; + + if (count >= size) + return -ENOMEM; + + len += count; + size -= count; + } + modalias[len] = '\0'; + return len; +} + +/** + * create_of_modalias - Creates DT compatible string for modalias and uevent + * @acpi_dev: ACPI device object. + * @modalias: Buffer to print into. + * @size: Size of the buffer. + * + * Expose DT compatible modalias as of:NnameTCcompatible. This function should + * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of + * ACPI/PNP IDs. + */ +static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias, + int size) +{ + struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; + const union acpi_object *of_compatible, *obj; + int len, count; + int i, nval; + char *c; + + acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf); + /* DT strings are all in lower case */ + for (c = buf.pointer; *c != '\0'; c++) + *c = tolower(*c); + + len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); + ACPI_FREE(buf.pointer); + + if (len <= 0) + return len; + + of_compatible = acpi_dev->data.of_compatible; + if (of_compatible->type == ACPI_TYPE_PACKAGE) { + nval = of_compatible->package.count; + obj = of_compatible->package.elements; + } else { /* Must be ACPI_TYPE_STRING. */ + nval = 1; + obj = of_compatible; + } + for (i = 0; i < nval; i++, obj++) { + count = snprintf(&modalias[len], size, "C%s", + obj->string.pointer); + if (count < 0) + return -EINVAL; + + if (count >= size) + return -ENOMEM; + + len += count; + size -= count; + } + modalias[len] = '\0'; + return len; +} + +int __acpi_device_uevent_modalias(struct acpi_device *adev, + struct kobj_uevent_env *env) +{ + int len; + + if (!adev) + return -ENODEV; + + if (list_empty(&adev->pnp.ids)) + return 0; + + if (add_uevent_var(env, "MODALIAS=")) + return -ENOMEM; + + len = create_pnp_modalias(adev, &env->buf[env->buflen - 1], + sizeof(env->buf) - env->buflen); + if (len < 0) + return len; + + env->buflen += len; + if (!adev->data.of_compatible) + return 0; + + if (len > 0 && add_uevent_var(env, "MODALIAS=")) + return -ENOMEM; + + len = create_of_modalias(adev, &env->buf[env->buflen - 1], + sizeof(env->buf) - env->buflen); + if (len < 0) + return len; + + env->buflen += len; + + return 0; +} + +/** + * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices. + * + * Create the uevent modalias field for ACPI-enumerated devices. + * + * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with + * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". + */ +int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) +{ + return __acpi_device_uevent_modalias(acpi_companion_match(dev), env); +} +EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias); + +static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size) +{ + int len, count; + + if (!adev) + return -ENODEV; + + if (list_empty(&adev->pnp.ids)) + return 0; + + len = create_pnp_modalias(adev, buf, size - 1); + if (len < 0) { + return len; + } else if (len > 0) { + buf[len++] = '\n'; + size -= len; + } + if (!adev->data.of_compatible) + return len; + + count = create_of_modalias(adev, buf + len, size - 1); + if (count < 0) { + return count; + } else if (count > 0) { + len += count; + buf[len++] = '\n'; + } + + return len; +} + +/** + * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices. + * + * Create the modalias sysfs attribute for ACPI-enumerated devices. + * + * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with + * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". + */ +int acpi_device_modalias(struct device *dev, char *buf, int size) +{ + return __acpi_device_modalias(acpi_companion_match(dev), buf, size); +} +EXPORT_SYMBOL_GPL(acpi_device_modalias); + +static ssize_t +acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) { + return __acpi_device_modalias(to_acpi_device(dev), buf, 1024); +} +static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL); + +static ssize_t real_power_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *adev = to_acpi_device(dev); + int state; + int ret; + + ret = acpi_device_get_power(adev, &state); + if (ret) + return ret; + + return sprintf(buf, "%s\n", acpi_power_state_string(state)); +} + +static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL); + +static ssize_t power_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *adev = to_acpi_device(dev); + + return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state)); +} + +static DEVICE_ATTR(power_state, 0444, power_state_show, NULL); + +static ssize_t +acpi_eject_store(struct device *d, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct acpi_device *acpi_device = to_acpi_device(d); + acpi_object_type not_used; + acpi_status status; + + if (!count || buf[0] != '1') + return -EINVAL; + + if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) + && !acpi_device->driver) + return -ENODEV; + + status = acpi_get_type(acpi_device->handle, ¬_used); + if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) + return -ENODEV; + + get_device(&acpi_device->dev); + status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT); + if (ACPI_SUCCESS(status)) + return count; + + put_device(&acpi_device->dev); + acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT, + ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL); + return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; +} + +static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store); + +static ssize_t +acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) { + struct acpi_device *acpi_dev = to_acpi_device(dev); + + return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev)); +} +static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL); + +static ssize_t acpi_device_uid_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + + return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id); +} +static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL); + +static ssize_t acpi_device_adr_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + + return sprintf(buf, "0x%08x\n", + (unsigned int)(acpi_dev->pnp.bus_address)); +} +static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL); + +static ssize_t +acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) { + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL}; + int result; + + result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path); + if (result) + goto end; + + result = sprintf(buf, "%s\n", (char*)path.pointer); + kfree(path.pointer); +end: + return result; +} +static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL); + +/* sysfs file that shows description text from the ACPI _STR method */ +static ssize_t description_show(struct device *dev, + struct device_attribute *attr, + char *buf) { + struct acpi_device *acpi_dev = to_acpi_device(dev); + int result; + + if (acpi_dev->pnp.str_obj == NULL) + return 0; + + /* + * The _STR object contains a Unicode identifier for a device. + * We need to convert to utf-8 so it can be displayed. + */ + result = utf16s_to_utf8s( + (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer, + acpi_dev->pnp.str_obj->buffer.length, + UTF16_LITTLE_ENDIAN, buf, + PAGE_SIZE); + + buf[result++] = '\n'; + + return result; +} +static DEVICE_ATTR(description, 0444, description_show, NULL); + +static ssize_t +acpi_device_sun_show(struct device *dev, struct device_attribute *attr, + char *buf) { + struct acpi_device *acpi_dev = to_acpi_device(dev); + acpi_status status; + unsigned long long sun; + + status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun); + if (ACPI_FAILURE(status)) + return -ENODEV; + + return sprintf(buf, "%llu\n", sun); +} +static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL); + +static ssize_t status_show(struct device *dev, struct device_attribute *attr, + char *buf) { + struct acpi_device *acpi_dev = to_acpi_device(dev); + acpi_status status; + unsigned long long sta; + + status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta); + if (ACPI_FAILURE(status)) + return -ENODEV; + + return sprintf(buf, "%llu\n", sta); +} +static DEVICE_ATTR_RO(status); + +/** + * acpi_device_setup_files - Create sysfs attributes of an ACPI device. + * @dev: ACPI device object. + */ +int acpi_device_setup_files(struct acpi_device *dev) +{ + struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; + acpi_status status; + int result = 0; + + /* + * Devices gotten from FADT don't have a "path" attribute + */ + if (dev->handle) { + result = device_create_file(&dev->dev, &dev_attr_path); + if (result) + goto end; + } + + if (!list_empty(&dev->pnp.ids)) { + result = device_create_file(&dev->dev, &dev_attr_hid); + if (result) + goto end; + + result = device_create_file(&dev->dev, &dev_attr_modalias); + if (result) + goto end; + } + + /* + * If device has _STR, 'description' file is created + */ + if (acpi_has_method(dev->handle, "_STR")) { + status = acpi_evaluate_object(dev->handle, "_STR", + NULL, &buffer); + if (ACPI_FAILURE(status)) + buffer.pointer = NULL; + dev->pnp.str_obj = buffer.pointer; + result = device_create_file(&dev->dev, &dev_attr_description); + if (result) + goto end; + } + + if (dev->pnp.type.bus_address) + result = device_create_file(&dev->dev, &dev_attr_adr); + if (dev->pnp.unique_id) + result = device_create_file(&dev->dev, &dev_attr_uid); + + if (acpi_has_method(dev->handle, "_SUN")) { + result = device_create_file(&dev->dev, &dev_attr_sun); + if (result) + goto end; + } + + if (acpi_has_method(dev->handle, "_STA")) { + result = device_create_file(&dev->dev, &dev_attr_status); + if (result) + goto end; + } + + /* + * If device has _EJ0, 'eject' file is created that is used to trigger + * hot-removal function from userland. + */ + if (acpi_has_method(dev->handle, "_EJ0")) { + result = device_create_file(&dev->dev, &dev_attr_eject); + if (result) + return result; + } + + if (dev->flags.power_manageable) { + result = device_create_file(&dev->dev, &dev_attr_power_state); + if (result) + return result; + + if (dev->power.flags.power_resources) + result = device_create_file(&dev->dev, + &dev_attr_real_power_state); + } + +end: + return result; +} + +/** + * acpi_device_remove_files - Remove sysfs attributes of an ACPI device. + * @dev: ACPI device object. + */ +void acpi_device_remove_files(struct acpi_device *dev) +{ + if (dev->flags.power_manageable) { + device_remove_file(&dev->dev, &dev_attr_power_state); + if (dev->power.flags.power_resources) + device_remove_file(&dev->dev, + &dev_attr_real_power_state); + } + + /* + * If device has _STR, remove 'description' file + */ + if (acpi_has_method(dev->handle, "_STR")) { + kfree(dev->pnp.str_obj); + device_remove_file(&dev->dev, &dev_attr_description); + } + /* + * If device has _EJ0, remove 'eject' file. + */ + if (acpi_has_method(dev->handle, "_EJ0")) + device_remove_file(&dev->dev, &dev_attr_eject); + + if (acpi_has_method(dev->handle, "_SUN")) + device_remove_file(&dev->dev, &dev_attr_sun); + + if (dev->pnp.unique_id) + device_remove_file(&dev->dev, &dev_attr_uid); + if (dev->pnp.type.bus_address) + device_remove_file(&dev->dev, &dev_attr_adr); + device_remove_file(&dev->dev, &dev_attr_modalias); + device_remove_file(&dev->dev, &dev_attr_hid); + if (acpi_has_method(dev->handle, "_STA")) + device_remove_file(&dev->dev, &dev_attr_status); + if (dev->handle) + device_remove_file(&dev->dev, &dev_attr_path); +} |