platform/x86: thinkpad_acpi: Add support to detect hardware damage detection capability. (28c43bdd) · Commits · git / linux-net

Documentation/admin-guide/laptops/thinkpad-acpi.rst

+22 −0

Original line number	Diff line number	Diff line
		@@ -54,6 +54,7 @@ detailed description):
		- Setting keyboard language
		- WWAN Antenna type
		- Auxmac
		- Hardware damage detection capability

		A compatibility table by model and feature is maintained on the web
		site, http://ibm-acpi.sf.net/. I appreciate any success or failure
		@@ -1576,6 +1577,27 @@ percentage level, above which charging will stop.
		The exact semantics of the attributes may be found in
		Documentation/ABI/testing/sysfs-class-power.

		Hardware damage detection capability
		------------------------------------

		sysfs attributes: hwdd_status

		Thinkpads are adding the ability to detect and report hardware damage.
		Add new sysfs interface to identify the damaged device status.
		Initial support is available for the USB-C replaceable connector.

		The command to check device damaged status is::

		cat /sys/devices/platform/thinkpad_acpi/hwdd_status

		This value displays status of device damaged.

		- 0 = Not Damaged
		- 1 = Damaged

		The property is read-only. If feature is not supported then sysfs
		attribute is not created.

		Multiple Commands, Module Parameters
		------------------------------------

drivers/platform/x86/lenovo/thinkpad_acpi.c

+106 −0

Original line number	Diff line number	Diff line
		@@ -36,6 +36,7 @@

		#include <linux/acpi.h>
		#include <linux/backlight.h>
		#include <linux/bitfield.h>
		#include <linux/bitops.h>
		#include <linux/delay.h>
		#include <linux/dmi.h>
		@@ -11080,6 +11081,106 @@ static const struct attribute_group auxmac_attr_group = {
		.attrs = auxmac_attributes,
		};

		/*************************************************************************
		* HWDD subdriver, for the Lenovo Hardware Damage Detection feature.
		*/

		#define HWDD_GET_DMG_USBC 0x80000001
		#define HWDD_GET_CAP 0
		#define HWDD_NOT_SUPPORTED BIT(31)
		#define HWDD_SUPPORT_USBC BIT(0)

		#define PORT_STATUS GENMASK(7, 4)
		#define NUM_PORTS 4

		static bool hwdd_support_available;
		static bool ucdd_supported;

		static int hwdd_command(int command, int *output)
		{
		acpi_handle hwdd_handle;

		if (ACPI_FAILURE(acpi_get_handle(hkey_handle, "HWDD", &hwdd_handle)))
		return -ENODEV;

		if (!acpi_evalf(hwdd_handle, output, NULL, "dd", command))
		return -EIO;

		return 0;
		}

		/* sysfs type-c damage detection capability */
		static ssize_t hwdd_status_show(struct device *dev,
		struct device_attribute *attr,
		char *buf)
		{
		unsigned int damage_status, port_status;
		int err, i;

		if (!ucdd_supported)
		return -ENODEV;

		/* Get USB TYPE-C damage status */
		err = hwdd_command(HWDD_GET_DMG_USBC, &damage_status);
		if (err)
		return err;

		port_status = FIELD_GET(PORT_STATUS, damage_status);
		for (i = 0; i < NUM_PORTS; i++) {
		if (!(damage_status & BIT(i)))
		continue;
		if (port_status & BIT(i))
		return sysfs_emit(buf, "1\n");
		}

		return sysfs_emit(buf, "0\n");
		}
		static DEVICE_ATTR_RO(hwdd_status);

		static struct attribute *hwdd_attributes[] = {
		&dev_attr_hwdd_status.attr,
		NULL
		};

		static umode_t hwdd_attr_is_visible(struct kobject *kobj,
		struct attribute *attr, int n)
		{
		return hwdd_support_available ? attr->mode : 0;
		}

		static const struct attribute_group hwdd_attr_group = {
		.is_visible = hwdd_attr_is_visible,
		.attrs = hwdd_attributes,
		};

		static int tpacpi_hwdd_init(struct ibm_init_struct *iibm)
		{
		int err, output;

		/* Below command checks the HWDD damage capability */
		err = hwdd_command(HWDD_GET_CAP, &output);
		if (err)
		return err;

		if (!(output & HWDD_NOT_SUPPORTED))
		return -ENODEV;

		hwdd_support_available = true;

		/*
		* BIT(0) is assigned to check capability of damage detection is
		* supported for USB Type-C port or not.
		*/
		if (output & HWDD_SUPPORT_USBC)
		ucdd_supported = true;

		return err;
		}

		static struct ibm_struct hwdd_driver_data = {
		.name = "hwdd",
		};

		/* --------------------------------------------------------------------- */

		static struct attribute *tpacpi_driver_attributes[] = {
		@@ -11139,6 +11240,7 @@ static const struct attribute_group *tpacpi_groups[] = {
		&kbdlang_attr_group,
		&dprc_attr_group,
		&auxmac_attr_group,
		&hwdd_attr_group,
		NULL,
		};

		@@ -11752,6 +11854,10 @@ static struct ibm_init_struct ibms_init[] __initdata = {
		.init = auxmac_init,
		.data = &auxmac_data,
		},
		{
		.init = tpacpi_hwdd_init,
		.data = &hwdd_driver_data,
		},
		};

		static int __init set_ibm_param(const char val, const struct kernel_param kp)