diff options
| -rw-r--r-- | drivers/platform/x86/toshiba_haps.c | 265 |
1 files changed, 265 insertions, 0 deletions
diff --git a/drivers/platform/x86/toshiba_haps.c b/drivers/platform/x86/toshiba_haps.c new file mode 100644 index 0000000..65300b6 --- /dev/null +++ b/drivers/platform/x86/toshiba_haps.c @@ -0,0 +1,265 @@ +/* + * Toshiba HDD Active Protection Sensor (HAPS) driver + * + * Copyright (C) 2014 Azael Avalos <coproscefalo@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/acpi.h> + +MODULE_AUTHOR("Azael Avalos <coproscefalo@gmail.com>"); +MODULE_DESCRIPTION("Toshiba HDD Active Protection Sensor"); +MODULE_LICENSE("GPL"); + +struct toshiba_haps_dev { + struct acpi_device *acpi_dev; + + int protection_level; +}; + +static struct toshiba_haps_dev *toshiba_haps; + +/* HAPS functions */ +static int toshiba_haps_reset_protection(acpi_handle handle) +{ + acpi_status status; + + status = acpi_evaluate_object(handle, "RSSS", NULL, NULL); + if (ACPI_FAILURE(status)) { + pr_err("Unable to reset the HDD protection\n"); + return -EIO; + } + + return 0; +} + +static int toshiba_haps_protection_level(acpi_handle handle, int level) +{ + acpi_status status; + + status = acpi_execute_simple_method(handle, "PTLV", level); + if (ACPI_FAILURE(status)) { + pr_err("Error while setting the protection level\n"); + return -EIO; + } + + pr_info("HDD protection level set to: %d\n", level); + + return 0; +} + +/* sysfs files */ +static ssize_t protection_level_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct toshiba_haps_dev *haps = dev_get_drvdata(dev); + + return sprintf(buf, "%i\n", haps->protection_level); +} + +static ssize_t protection_level_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct toshiba_haps_dev *haps = dev_get_drvdata(dev); + int level, ret; + + if (sscanf(buf, "%d", &level) != 1 || level < 0 || level > 3) + return -EINVAL; + + /* Set the sensor level. + * Acceptable levels are: + * 0 - Disabled | 1 - Low | 2 - Medium | 3 - High + */ + ret = toshiba_haps_protection_level(haps->acpi_dev->handle, level); + if (ret != 0) + return ret; + + haps->protection_level = level; + + return count; +} + +static ssize_t reset_protection_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct toshiba_haps_dev *haps = dev_get_drvdata(dev); + int reset, ret; + + if (sscanf(buf, "%d", &reset) != 1 || reset != 1) + return -EINVAL; + + /* Reset the protection interface */ + ret = toshiba_haps_reset_protection(haps->acpi_dev->handle); + if (ret != 0) + return ret; + + return count; +} + +static DEVICE_ATTR(protection_level, S_IRUGO | S_IWUSR, + protection_level_show, protection_level_store); +static DEVICE_ATTR(reset_protection, S_IWUSR, NULL, reset_protection_store); + +static struct attribute *haps_attributes[] = { + &dev_attr_protection_level.attr, + &dev_attr_reset_protection.attr, + NULL, +}; + +static struct attribute_group haps_attr_group = { + .attrs = haps_attributes, +}; + +/* + * ACPI stuff + */ +static void toshiba_haps_notify(struct acpi_device *device, u32 event) +{ + pr_info("Received event: 0x%x", event); + + acpi_bus_generate_netlink_event(device->pnp.device_class, + dev_name(&device->dev), + event, 0); +} + +static int toshiba_haps_remove(struct acpi_device *device) +{ + sysfs_remove_group(&device->dev.kobj, &haps_attr_group); + + if (toshiba_haps) + toshiba_haps = NULL; + + return 0; +} + +/* Helper function */ +static int toshiba_haps_available(acpi_handle handle) +{ + acpi_status status; + u64 hdd_present; + + /* + * A non existent device as well as having (only) + * Solid State Drives can cause the call to fail. + */ + status = acpi_evaluate_integer(handle, "_STA", NULL, + &hdd_present); + if (ACPI_FAILURE(status) || !hdd_present) { + pr_info("HDD protection not available or using SSD\n"); + return 0; + } + + return 1; +} + +static int toshiba_haps_add(struct acpi_device *acpi_dev) +{ + struct toshiba_haps_dev *haps; + int ret; + + if (toshiba_haps) + return -EBUSY; + + if (!toshiba_haps_available(acpi_dev->handle)) + return -ENODEV; + + pr_info("Toshiba HDD Active Protection Sensor device\n"); + + haps = kzalloc(sizeof(struct toshiba_haps_dev), GFP_KERNEL); + if (!haps) + return -ENOMEM; + + haps->acpi_dev = acpi_dev; + haps->protection_level = 2; + acpi_dev->driver_data = haps; + dev_set_drvdata(&acpi_dev->dev, haps); + + /* Set the protection level, currently at level 2 (Medium) */ + ret = toshiba_haps_protection_level(acpi_dev->handle, 2); + if (ret != 0) + return ret; + + ret = sysfs_create_group(&acpi_dev->dev.kobj, &haps_attr_group); + if (ret) + return ret; + + toshiba_haps = haps; + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int toshiba_haps_suspend(struct device *device) +{ + struct toshiba_haps_dev *haps; + int ret; + + haps = acpi_driver_data(to_acpi_device(device)); + + /* Deactivate the protection on suspend */ + ret = toshiba_haps_protection_level(haps->acpi_dev->handle, 0); + + return ret; +} + +static int toshiba_haps_resume(struct device *device) +{ + struct toshiba_haps_dev *haps; + int ret; + + haps = acpi_driver_data(to_acpi_device(device)); + + /* Set the stored protection level */ + ret = toshiba_haps_protection_level(haps->acpi_dev->handle, + haps->protection_level); + + /* Reset the protection on resume */ + ret = toshiba_haps_reset_protection(haps->acpi_dev->handle); + if (ret != 0) + return ret; + + return ret; +} +#endif + +static SIMPLE_DEV_PM_OPS(toshiba_haps_pm, + toshiba_haps_suspend, toshiba_haps_resume); + +static const struct acpi_device_id haps_device_ids[] = { + {"TOS620A", 0}, + {"", 0}, +}; +MODULE_DEVICE_TABLE(acpi, haps_device_ids); + +static struct acpi_driver toshiba_haps_driver = { + .name = "Toshiba HAPS", + .owner = THIS_MODULE, + .ids = haps_device_ids, + .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS, + .ops = { + .add = toshiba_haps_add, + .remove = toshiba_haps_remove, + .notify = toshiba_haps_notify, + }, + .drv.pm = &toshiba_haps_pm, +}; + +module_acpi_driver(toshiba_haps_driver); |
