Commit f809891e authored by Hans de Goede's avatar Hans de Goede
Browse files

platform/x86: thinkpad_acpi: Register a privacy-screen device 



Register a privacy-screen device on laptops with a privacy-screen,
this exports the PrivacyGuard features to user-space using a
standardized vendor-agnostic sysfs interface. Note the sysfs interface
is read-only.

Registering a privacy-screen device with the new privacy-screen class
code will also allow the GPU driver to get a handle to it and export
the privacy-screen setting as a property on the DRM connector object
for the LCD panel. This DRM connector property is a new standardized
interface which all user-space code should use to query and control
the privacy-screen.

Reviewed-by: default avatarEmil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: default avatarLyude Paul <lyude@redhat.com>
Reviewed-by: default avatarMark Pearson <markpearson@lenovo.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005202322.700909-9-hdegoede@redhat.com
parent e8b7eb66

drivers/platform/x86/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -501,7 +501,9 @@ config THINKPAD_ACPI 
	depends on ACPI_VIDEO || ACPI_VIDEO = n

	depends on BACKLIGHT_CLASS_DEVICE

	depends on I2C

	depends on DRM

	select ACPI_PLATFORM_PROFILE

	select DRM_PRIVACY_SCREEN

	select HWMON

	select NVRAM

	select NEW_LEDS

drivers/platform/x86/thinkpad_acpi.c

+72 −25
Original line number Diff line number Diff line
@@ -73,6 +73,7 @@ 
#include <linux/uaccess.h>

#include <acpi/battery.h>

#include <acpi/video.h>

#include <drm/drm_privacy_screen_driver.h>

#include "dual_accel_detect.h"



/* ThinkPad CMOS commands */
@@ -157,6 +158,7 @@ enum tpacpi_hkey_event_t { 
	TP_HKEY_EV_VOL_UP		= 0x1015, /* Volume up or unmute */

	TP_HKEY_EV_VOL_DOWN		= 0x1016, /* Volume down or unmute */

	TP_HKEY_EV_VOL_MUTE		= 0x1017, /* Mixer output mute */

	TP_HKEY_EV_PRIVACYGUARD_TOGGLE	= 0x130f, /* Toggle priv.guard on/off */



	/* Reasons for waking up from S3/S4 */

	TP_HKEY_EV_WKUP_S3_UNDOCK	= 0x2304, /* undock requested, S3 */
@@ -3889,6 +3891,12 @@ static bool hotkey_notify_extended_hotkey(const u32 hkey) 
{

	unsigned int scancode;



	switch (hkey) {

	case TP_HKEY_EV_PRIVACYGUARD_TOGGLE:

		tpacpi_driver_event(hkey);

		return true;

	}



	/* Extended keycodes start at 0x300 and our offset into the map

	 * TP_ACPI_HOTKEYSCAN_EXTENDED_START. The calculated scancode

	 * will be positive, but might not be in the correct range.
@@ -9819,30 +9827,40 @@ static struct ibm_struct battery_driver_data = { 
 * LCD Shadow subdriver, for the Lenovo PrivacyGuard feature

 */



static struct drm_privacy_screen *lcdshadow_dev;

static acpi_handle lcdshadow_get_handle;

static acpi_handle lcdshadow_set_handle;

static int lcdshadow_state;



static int lcdshadow_on_off(bool state)

static int lcdshadow_set_sw_state(struct drm_privacy_screen *priv,

				  enum drm_privacy_screen_status state)

{

	int output;



	if (WARN_ON(!mutex_is_locked(&priv->lock)))

		return -EIO;



	if (!acpi_evalf(lcdshadow_set_handle, &output, NULL, "dd", (int)state))

		return -EIO;



	lcdshadow_state = state;

	priv->hw_state = priv->sw_state = state;

	return 0;

}



static int lcdshadow_set(bool on)

static void lcdshadow_get_hw_state(struct drm_privacy_screen *priv)

{

	if (lcdshadow_state < 0)

		return lcdshadow_state;

	if (lcdshadow_state == on)

		return 0;

	return lcdshadow_on_off(on);

	int output;



	if (!acpi_evalf(lcdshadow_get_handle, &output, NULL, "dd", 0))

		return;



	priv->hw_state = priv->sw_state = output & 0x1;

}



static const struct drm_privacy_screen_ops lcdshadow_ops = {

	.set_sw_state = lcdshadow_set_sw_state,

	.get_hw_state = lcdshadow_get_hw_state,

};



static int tpacpi_lcdshadow_init(struct ibm_init_struct *iibm)

{

	acpi_status status1, status2;
@@ -9850,36 +9868,44 @@ static int tpacpi_lcdshadow_init(struct ibm_init_struct *iibm) 


	status1 = acpi_get_handle(hkey_handle, "GSSS", &lcdshadow_get_handle);

	status2 = acpi_get_handle(hkey_handle, "SSSS", &lcdshadow_set_handle);

	if (ACPI_FAILURE(status1) || ACPI_FAILURE(status2)) {

		lcdshadow_state = -ENODEV;

	if (ACPI_FAILURE(status1) || ACPI_FAILURE(status2))

		return 0;

	}



	if (!acpi_evalf(lcdshadow_get_handle, &output, NULL, "dd", 0)) {

		lcdshadow_state = -EIO;

	if (!acpi_evalf(lcdshadow_get_handle, &output, NULL, "dd", 0))

		return -EIO;

	}

	if (!(output & 0x10000)) {

		lcdshadow_state = -ENODEV;



	if (!(output & 0x10000))

		return 0;

	}

	lcdshadow_state = output & 0x1;



	lcdshadow_dev = drm_privacy_screen_register(&tpacpi_pdev->dev,

						    &lcdshadow_ops);

	if (IS_ERR(lcdshadow_dev))

		return PTR_ERR(lcdshadow_dev);



	return 0;

}



static void lcdshadow_exit(void)

{

	drm_privacy_screen_unregister(lcdshadow_dev);

}



static void lcdshadow_resume(void)

{

	if (lcdshadow_state >= 0)

		lcdshadow_on_off(lcdshadow_state);

	if (!lcdshadow_dev)

		return;



	mutex_lock(&lcdshadow_dev->lock);

	lcdshadow_set_sw_state(lcdshadow_dev, lcdshadow_dev->sw_state);

	mutex_unlock(&lcdshadow_dev->lock);

}



static int lcdshadow_read(struct seq_file *m)

{

	if (lcdshadow_state < 0) {

	if (!lcdshadow_dev) {

		seq_puts(m, "status:\t\tnot supported\n");

	} else {

		seq_printf(m, "status:\t\t%d\n", lcdshadow_state);

		seq_printf(m, "status:\t\t%d\n", lcdshadow_dev->hw_state);

		seq_puts(m, "commands:\t0, 1\n");

	}
@@ -9891,7 +9917,7 @@ static int lcdshadow_write(char *buf) 
	char *cmd;

	int res, state = -EINVAL;



	if (lcdshadow_state < 0)

	if (!lcdshadow_dev)

		return -ENODEV;



	while ((cmd = strsep(&buf, ","))) {
@@ -9903,11 +9929,18 @@ static int lcdshadow_write(char *buf) 
	if (state >= 2 || state < 0)

		return -EINVAL;



	return lcdshadow_set(state);

	mutex_lock(&lcdshadow_dev->lock);

	res = lcdshadow_set_sw_state(lcdshadow_dev, state);

	mutex_unlock(&lcdshadow_dev->lock);



	drm_privacy_screen_call_notifier_chain(lcdshadow_dev);



	return res;

}



static struct ibm_struct lcdshadow_driver_data = {

	.name = "lcdshadow",

	.exit = lcdshadow_exit,

	.resume = lcdshadow_resume,

	.read = lcdshadow_read,

	.write = lcdshadow_write,
@@ -10717,6 +10750,20 @@ static void tpacpi_driver_event(const unsigned int hkey_event) 
		if (!atomic_add_unless(&dytc_ignore_event, -1, 0))

			dytc_profile_refresh();

	}



	if (lcdshadow_dev && hkey_event == TP_HKEY_EV_PRIVACYGUARD_TOGGLE) {

		enum drm_privacy_screen_status old_hw_state;

		bool changed;



		mutex_lock(&lcdshadow_dev->lock);

		old_hw_state = lcdshadow_dev->hw_state;

		lcdshadow_get_hw_state(lcdshadow_dev);

		changed = lcdshadow_dev->hw_state != old_hw_state;

		mutex_unlock(&lcdshadow_dev->lock);



		if (changed)

			drm_privacy_screen_call_notifier_chain(lcdshadow_dev);

	}

}



static void hotkey_driver_event(const unsigned int scancode)