Re: [PATCH] Add Lenovo PrivacyGuard feature found in T480s, T490, T490s

Re: [PATCH] Add Lenovo PrivacyGuard feature found in T480s, T490, T490s

[Andy Shevchenko]

On Tue, May 21, 2019 at 3:56 PM Alexander Schremmer
<alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org> wrote:
> I wonder whether you have received my kernel patch, referenced below. It
> might have been caught by the spam filter.

Yes, you may always consult with patchwork [1]. If it's they, it won't be lost.

[1]: https://patchwork.kernel.org/project/platform-driver-x86/list/

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] Add Lenovo PrivacyGuard feature found in T480s, T490, T490s

[Andy Shevchenko]

On Sun, May 19, 2019 at 7:46 PM Alexander Schremmer
<alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org> wrote:
>
> From 6bfe30cae2be3f4fbe9f9990a4e83302569ff7e9 Mon Sep 17 00:00:00 2001
> From: Alexander Schremmer <alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org>
> Date: Sun, 19 May 2019 18:13:05 +0200
> Subject: [PATCH] platform/x86: Add Lenovo ThinkPad PrivacyGuard.
>
> This feature is found optionally in T480s, T490, T490s.
>
> The feature is called lcdshadow and visible via
> /proc/acpi/ibm/lcdshadow.
>
> The ACPI methods \_SB.PCI0.LPCB.EC.HKEY.{GSSS,SSSS,TSSS,CSSS} are
> available in these machines. They get, set, toggle or change the state
> apparently.
>
> The patch was tested on a 5.0 series kernel on a T480s.

While being in my review and testing queue it doesn't produce any
warnings the ABI extension lacks of documentation part.

>
> Signed-off-by: Alexander Schremmer <alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org>
> ---
>  drivers/platform/x86/thinkpad_acpi.c | 108 +++++++++++++++++++++++++++
>  1 file changed, 108 insertions(+)
>
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index 71cfaf26efd1..f2603643b067 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -9729,6 +9729,110 @@ static struct ibm_struct battery_driver_data = {
>         .exit = tpacpi_battery_exit,
>  };
>
> +/*************************************************************************
> + * LCD Shadow subdriver, for the Lenovo PrivacyGuard feature
> + */
> +
> +
> +static int lcdshadow_state;
> +
> +static int lcdshadow_on_off(bool state)
> +{
> +       acpi_handle set_shadow_handle;
> +       int output;
> +
> +       if (ACPI_FAILURE(acpi_get_handle(
> +                                       hkey_handle,
> +                                       "SSSS",
> +                                       &set_shadow_handle))) {
> +               pr_warn("Thinkpad ACPI has no %s interface.\n", "SSSS");
> +               return -EIO;
> +       }
> +
> +       if (!acpi_evalf(set_shadow_handle, &output, NULL, "dd", (int)state))
> +               return -EIO;
> +
> +       lcdshadow_state = state;
> +       return 0;
> +}
> +
> +static int lcdshadow_set(bool on)
> +{
> +       if (lcdshadow_state < 0 || lcdshadow_state == on)
> +               return lcdshadow_state;
> +       return lcdshadow_on_off(on);
> +}
> +
> +static int tpacpi_lcdshadow_init(struct ibm_init_struct *iibm)
> +{
> +       acpi_handle get_shadow_handle;
> +       int output;
> +
> +       if (ACPI_FAILURE(acpi_get_handle(
> +                                       hkey_handle,
> +                                       "GSSS",
> +                                       &get_shadow_handle))) {
> +               lcdshadow_state = -ENODEV;
> +               return 0;
> +       }
> +
> +       if (!acpi_evalf(get_shadow_handle, &output, NULL, "dd", 0))
> +               return -EIO;
> +       if (!(output & 0x10000)) {
> +               lcdshadow_state = -ENODEV;
> +               return 0;
> +       }
> +       lcdshadow_state = output & 0x1;
> +
> +       return 0;
> +}
> +
> +static void lcdshadow_resume(void)
> +{
> +       if (lcdshadow_state >= 0)
> +               lcdshadow_on_off(lcdshadow_state);
> +}
> +
> +static int lcdshadow_read(struct seq_file *m)
> +{
> +       if (lcdshadow_state < 0) {
> +               seq_puts(m, "status:\t\tnot supported\n");
> +       } else {
> +               seq_printf(m, "status:\t\t%d\n", lcdshadow_state);
> +               seq_puts(m, "commands:\t0, 1\n");
> +       }
> +
> +       return 0;
> +}
> +
> +static int lcdshadow_write(char *buf)
> +{
> +       char *cmd;
> +       int state = -1;
> +
> +       if (lcdshadow_state < 0)
> +               return -ENODEV;
> +
> +       while ((cmd = next_cmd(&buf))) {
> +               if (strlencmp(cmd, "0") == 0)
> +                       state = 0;
> +               else if (strlencmp(cmd, "1") == 0)
> +                       state = 1;
> +       }
> +
> +       if (state == -1)
> +               return -EINVAL;
> +
> +       return lcdshadow_set(state);
> +}
> +
> +static struct ibm_struct lcdshadow_driver_data = {
> +       .name = "lcdshadow",
> +       .resume = lcdshadow_resume,
> +       .read = lcdshadow_read,
> +       .write = lcdshadow_write,
> +};
> +
>  /****************************************************************************
>   ****************************************************************************
>   *
> @@ -10210,6 +10314,10 @@ static struct ibm_init_struct ibms_init[] __initdata = {
>                 .init = tpacpi_battery_init,
>                 .data = &battery_driver_data,
>         },
> +       {
> +               .init = tpacpi_lcdshadow_init,
> +               .data = &lcdshadow_driver_data,
> +       },
>  };
>
>  static int __init set_ibm_param(const char *val, const struct kernel_param *kp)
> --
> 2.20.1
>


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] platform/x86: Add Lenovo ThinkPad PrivacyGuard.

[Andy Shevchenko]

On Wed, Jul 10, 2019 at 6:32 PM Alexander Schremmer
<alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org> wrote:
>
> This feature is found optionally in T480s, T490, T490s.
>
> The feature is called lcdshadow and visible via
> /proc/acpi/ibm/lcdshadow.
>
> The ACPI methods \_SB.PCI0.LPCB.EC.HKEY.{GSSS,SSSS,TSSS,CSSS} are
> available in these machines. They get, set, toggle or change the state
> apparently.
>
> The patch was tested on a 5.0 series kernel on a T480s.
>

Thanks for an update!
Unfortunately it doesn't apply since big batch of txt->rst conversion
happened in this cycle. Care to fix and resend?

> Signed-off-by: Alexander Schremmer <alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org>
> ---
>  Documentation/laptops/thinkpad-acpi.txt |  22 +++++
>  drivers/platform/x86/thinkpad_acpi.c    | 112 ++++++++++++++++++++++++
>  2 files changed, 134 insertions(+)
>
> diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
> index 6cced88de6da..3fff4b5b6aab 100644
> --- a/Documentation/laptops/thinkpad-acpi.txt
> +++ b/Documentation/laptops/thinkpad-acpi.txt
> @@ -46,6 +46,7 @@ detailed description):
>         - Fan control and monitoring: fan speed, fan enable/disable
>         - WAN enable and disable
>         - UWB enable and disable
> +       - LCD Shadow (PrivacyGuard) enable and disable
>
>  A compatibility table by model and feature is maintained on the web
>  site, http://ibm-acpi.sf.net/. I appreciate any success or failure
> @@ -1341,6 +1342,27 @@ Sysfs notes:
>         Documentation/rfkill.txt for details.
>
>
> +LCD Shadow control
> +------------------
> +
> +procfs: /proc/acpi/ibm/lcdshadow
> +
> +Some newer T480s and T490s ThinkPads provide a feature called
> +PrivacyGuard. By turning this feature on, the usable vertical and
> +horizontal viewing angles of the LCD can be limited (as if some privacy
> +screen was applied manually in front of the display).
> +
> +procfs notes:
> +
> +The available commands are:
> +
> +       echo '0' >/proc/acpi/ibm/lcdshadow
> +       echo '1' >/proc/acpi/ibm/lcdshadow
> +
> +The first command ensures the best viewing angle and the latter one turns
> +on the feature, restricting the viewing angles.
> +
> +
>  EXPERIMENTAL: UWB
>  -----------------
>
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index 71cfaf26efd1..8907b183b940 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -9729,6 +9729,114 @@ static struct ibm_struct battery_driver_data = {
>         .exit = tpacpi_battery_exit,
>  };
>
> +/*************************************************************************
> + * LCD Shadow subdriver, for the Lenovo PrivacyGuard feature
> + */
> +
> +
> +static int lcdshadow_state;
> +
> +static int lcdshadow_on_off(bool state)
> +{
> +       acpi_handle set_shadow_handle;
> +       int output;
> +
> +       if (ACPI_FAILURE(acpi_get_handle(
> +                                       hkey_handle,
> +                                       "SSSS",
> +                                       &set_shadow_handle))) {
> +               pr_warn("Thinkpad ACPI has no %s interface.\n", "SSSS");
> +               return -EIO;
> +       }
> +
> +       if (!acpi_evalf(set_shadow_handle, &output, NULL, "dd", (int)state))
> +               return -EIO;
> +
> +       lcdshadow_state = state;
> +       return 0;
> +}
> +
> +static int lcdshadow_set(bool on)
> +{
> +       if (lcdshadow_state < 0)
> +               return lcdshadow_state;
> +       if (lcdshadow_state == on)
> +               return 0;
> +       return lcdshadow_on_off(on);
> +}
> +
> +static int tpacpi_lcdshadow_init(struct ibm_init_struct *iibm)
> +{
> +       acpi_handle get_shadow_handle;
> +       int output;
> +
> +       if (ACPI_FAILURE(acpi_get_handle(
> +                                       hkey_handle,
> +                                       "GSSS",
> +                                       &get_shadow_handle))) {
> +               lcdshadow_state = -ENODEV;
> +               return 0;
> +       }
> +
> +       if (!acpi_evalf(get_shadow_handle, &output, NULL, "dd", 0)) {
> +               lcdshadow_state = -EIO;
> +               return -EIO;
> +       }
> +       if (!(output & 0x10000)) {
> +               lcdshadow_state = -ENODEV;
> +               return 0;
> +       }
> +       lcdshadow_state = output & 0x1;
> +
> +       return 0;
> +}
> +
> +static void lcdshadow_resume(void)
> +{
> +       if (lcdshadow_state >= 0)
> +               lcdshadow_on_off(lcdshadow_state);
> +}
> +
> +static int lcdshadow_read(struct seq_file *m)
> +{
> +       if (lcdshadow_state < 0) {
> +               seq_puts(m, "status:\t\tnot supported\n");
> +       } else {
> +               seq_printf(m, "status:\t\t%d\n", lcdshadow_state);
> +               seq_puts(m, "commands:\t0, 1\n");
> +       }
> +
> +       return 0;
> +}
> +
> +static int lcdshadow_write(char *buf)
> +{
> +       char *cmd;
> +       int state = -1;
> +
> +       if (lcdshadow_state < 0)
> +               return -ENODEV;
> +
> +       while ((cmd = next_cmd(&buf))) {
> +               if (strlencmp(cmd, "0") == 0)
> +                       state = 0;
> +               else if (strlencmp(cmd, "1") == 0)
> +                       state = 1;
> +       }
> +
> +       if (state == -1)
> +               return -EINVAL;
> +
> +       return lcdshadow_set(state);
> +}
> +
> +static struct ibm_struct lcdshadow_driver_data = {
> +       .name = "lcdshadow",
> +       .resume = lcdshadow_resume,
> +       .read = lcdshadow_read,
> +       .write = lcdshadow_write,
> +};
> +
>  /****************************************************************************
>   ****************************************************************************
>   *
> @@ -10210,6 +10318,10 @@ static struct ibm_init_struct ibms_init[] __initdata = {
>                 .init = tpacpi_battery_init,
>                 .data = &battery_driver_data,
>         },
> +       {
> +               .init = tpacpi_lcdshadow_init,
> +               .data = &lcdshadow_driver_data,
> +       },
>  };
>
>  static int __init set_ibm_param(const char *val, const struct kernel_param *kp)
> --
> 2.20.1
>


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] platform/x86: Add Lenovo ThinkPad PrivacyGuard.

[Andy Shevchenko]

On Thu, Aug 22, 2019 at 2:48 PM Alexander Schremmer
<alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org> wrote:
>
> This feature is found optionally in T480s, T490, T490s.
>
> The feature is called lcdshadow and visible via
> /proc/acpi/ibm/lcdshadow.
>
> The ACPI methods \_SB.PCI0.LPCB.EC.HKEY.{GSSS,SSSS,TSSS,CSSS} are
> available in these machines. They get, set, toggle or change the state
> apparently.
>
> The patch was tested on a 5.0 series kernel on a T480s.
>

Pushed to my review and testing queue, thanks!

> Signed-off-by: Alexander Schremmer <alex-y2PnNNZjvYf3t9wD0PK9CA@public.gmane.org>
> ---
>  .../admin-guide/laptops/thinkpad-acpi.rst     |  23 ++++
>  drivers/platform/x86/thinkpad_acpi.c          | 112 ++++++++++++++++++
>  2 files changed, 135 insertions(+)
>
> diff --git a/Documentation/admin-guide/laptops/thinkpad-acpi.rst b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
> index adea0bf2acc5..822907dcc845 100644
> --- a/Documentation/admin-guide/laptops/thinkpad-acpi.rst
> +++ b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
> @@ -49,6 +49,7 @@ detailed description):
>         - Fan control and monitoring: fan speed, fan enable/disable
>         - WAN enable and disable
>         - UWB enable and disable
> +       - LCD Shadow (PrivacyGuard) enable and disable
>
>  A compatibility table by model and feature is maintained on the web
>  site, http://ibm-acpi.sf.net/. I appreciate any success or failure
> @@ -1409,6 +1410,28 @@ Sysfs notes
>         Documentation/driver-api/rfkill.rst for details.
>
>
> +LCD Shadow control
> +------------------
> +
> +procfs: /proc/acpi/ibm/lcdshadow
> +
> +Some newer T480s and T490s ThinkPads provide a feature called
> +PrivacyGuard. By turning this feature on, the usable vertical and
> +horizontal viewing angles of the LCD can be limited (as if some privacy
> +screen was applied manually in front of the display).
> +
> +procfs notes
> +^^^^^^^^^^^^
> +
> +The available commands are::
> +
> +       echo '0' >/proc/acpi/ibm/lcdshadow
> +       echo '1' >/proc/acpi/ibm/lcdshadow
> +
> +The first command ensures the best viewing angle and the latter one turns
> +on the feature, restricting the viewing angles.
> +
> +
>  EXPERIMENTAL: UWB
>  -----------------
>
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index 7bde4640ef34..12bf573c6568 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -9714,6 +9714,114 @@ static struct ibm_struct battery_driver_data = {
>         .exit = tpacpi_battery_exit,
>  };
>
> +/*************************************************************************
> + * LCD Shadow subdriver, for the Lenovo PrivacyGuard feature
> + */
> +
> +
> +static int lcdshadow_state;
> +
> +static int lcdshadow_on_off(bool state)
> +{
> +       acpi_handle set_shadow_handle;
> +       int output;
> +
> +       if (ACPI_FAILURE(acpi_get_handle(
> +                                       hkey_handle,
> +                                       "SSSS",
> +                                       &set_shadow_handle))) {
> +               pr_warn("Thinkpad ACPI has no %s interface.\n", "SSSS");
> +               return -EIO;
> +       }
> +
> +       if (!acpi_evalf(set_shadow_handle, &output, NULL, "dd", (int)state))
> +               return -EIO;
> +
> +       lcdshadow_state = state;
> +       return 0;
> +}
> +
> +static int lcdshadow_set(bool on)
> +{
> +       if (lcdshadow_state < 0)
> +               return lcdshadow_state;
> +       if (lcdshadow_state == on)
> +               return 0;
> +       return lcdshadow_on_off(on);
> +}
> +
> +static int tpacpi_lcdshadow_init(struct ibm_init_struct *iibm)
> +{
> +       acpi_handle get_shadow_handle;
> +       int output;
> +
> +       if (ACPI_FAILURE(acpi_get_handle(
> +                                       hkey_handle,
> +                                       "GSSS",
> +                                       &get_shadow_handle))) {
> +               lcdshadow_state = -ENODEV;
> +               return 0;
> +       }
> +
> +       if (!acpi_evalf(get_shadow_handle, &output, NULL, "dd", 0)) {
> +               lcdshadow_state = -EIO;
> +               return -EIO;
> +       }
> +       if (!(output & 0x10000)) {
> +               lcdshadow_state = -ENODEV;
> +               return 0;
> +       }
> +       lcdshadow_state = output & 0x1;
> +
> +       return 0;
> +}
> +
> +static void lcdshadow_resume(void)
> +{
> +       if (lcdshadow_state >= 0)
> +               lcdshadow_on_off(lcdshadow_state);
> +}
> +
> +static int lcdshadow_read(struct seq_file *m)
> +{
> +       if (lcdshadow_state < 0) {
> +               seq_puts(m, "status:\t\tnot supported\n");
> +       } else {
> +               seq_printf(m, "status:\t\t%d\n", lcdshadow_state);
> +               seq_puts(m, "commands:\t0, 1\n");
> +       }
> +
> +       return 0;
> +}
> +
> +static int lcdshadow_write(char *buf)
> +{
> +       char *cmd;
> +       int state = -1;
> +
> +       if (lcdshadow_state < 0)
> +               return -ENODEV;
> +
> +       while ((cmd = next_cmd(&buf))) {
> +               if (strlencmp(cmd, "0") == 0)
> +                       state = 0;
> +               else if (strlencmp(cmd, "1") == 0)
> +                       state = 1;
> +       }
> +
> +       if (state == -1)
> +               return -EINVAL;
> +
> +       return lcdshadow_set(state);
> +}
> +
> +static struct ibm_struct lcdshadow_driver_data = {
> +       .name = "lcdshadow",
> +       .resume = lcdshadow_resume,
> +       .read = lcdshadow_read,
> +       .write = lcdshadow_write,
> +};
> +
>  /****************************************************************************
>   ****************************************************************************
>   *
> @@ -10195,6 +10303,10 @@ static struct ibm_init_struct ibms_init[] __initdata = {
>                 .init = tpacpi_battery_init,
>                 .data = &battery_driver_data,
>         },
> +       {
> +               .init = tpacpi_lcdshadow_init,
> +               .data = &lcdshadow_driver_data,
> +       },
>  };
>
>  static int __init set_ibm_param(const char *val, const struct kernel_param *kp)
> --
> 2.20.1
>


--
With Best Regards,
Andy Shevchenko

Re: [PATCH] platform/x86: Add Lenovo ThinkPad PrivacyGuard.

[Pali Rohár]

On Thursday 22 August 2019 13:48:33 Alexander Schremmer wrote:
> This feature is found optionally in T480s, T490, T490s.
> 
> The feature is called lcdshadow and visible via
> /proc/acpi/ibm/lcdshadow.
> 
> The ACPI methods \_SB.PCI0.LPCB.EC.HKEY.{GSSS,SSSS,TSSS,CSSS} are
> available in these machines. They get, set, toggle or change the state
> apparently.
> 
> The patch was tested on a 5.0 series kernel on a T480s.
> 
> Signed-off-by: Alexander Schremmer <alex@alexanderweb.de>
> ---
>  .../admin-guide/laptops/thinkpad-acpi.rst     |  23 ++++
>  drivers/platform/x86/thinkpad_acpi.c          | 112 ++++++++++++++++++
>  2 files changed, 135 insertions(+)
> 
> diff --git a/Documentation/admin-guide/laptops/thinkpad-acpi.rst b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
> index adea0bf2acc5..822907dcc845 100644
> --- a/Documentation/admin-guide/laptops/thinkpad-acpi.rst
> +++ b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
> @@ -49,6 +49,7 @@ detailed description):
>  	- Fan control and monitoring: fan speed, fan enable/disable
>  	- WAN enable and disable
>  	- UWB enable and disable
> +	- LCD Shadow (PrivacyGuard) enable and disable
>  
>  A compatibility table by model and feature is maintained on the web
>  site, http://ibm-acpi.sf.net/. I appreciate any success or failure
> @@ -1409,6 +1410,28 @@ Sysfs notes
>  	Documentation/driver-api/rfkill.rst for details.
>  
>  
> +LCD Shadow control
> +------------------
> +
> +procfs: /proc/acpi/ibm/lcdshadow
> +
> +Some newer T480s and T490s ThinkPads provide a feature called
> +PrivacyGuard. By turning this feature on, the usable vertical and
> +horizontal viewing angles of the LCD can be limited (as if some privacy
> +screen was applied manually in front of the display).
> +
> +procfs notes
> +^^^^^^^^^^^^
> +
> +The available commands are::
> +
> +	echo '0' >/proc/acpi/ibm/lcdshadow
> +	echo '1' >/proc/acpi/ibm/lcdshadow
> +
> +The first command ensures the best viewing angle and the latter one turns
> +on the feature, restricting the viewing angles.
> +
> +
>  EXPERIMENTAL: UWB
>  -----------------

Hello! Is not the whole /proc/apci/ibm API for new things obsoleted or deprecated?
And should not rather it use platform driver in /sys/ (class?) namespace?

-- 
Pali Rohár
pali.rohar@gmail.com


_______________________________________________
ibm-acpi-devel mailing list
ibm-acpi-devel@lists.sourceforge.net
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Re: [PATCH] platform/x86: Add Lenovo ThinkPad PrivacyGuard.

[Andy Shevchenko]

On Fri, Oct 25, 2019 at 2:33 PM Pali Rohár <pali.rohar@gmail.com> wrote:
> On Thursday 22 August 2019 13:48:33 Alexander Schremmer wrote:
> > This feature is found optionally in T480s, T490, T490s.
> >
> > The feature is called lcdshadow and visible via
> > /proc/acpi/ibm/lcdshadow.
> >
> > The ACPI methods \_SB.PCI0.LPCB.EC.HKEY.{GSSS,SSSS,TSSS,CSSS} are
> > available in these machines. They get, set, toggle or change the state
> > apparently.
> >
> > The patch was tested on a 5.0 series kernel on a T480s.

> > +     echo '0' >/proc/acpi/ibm/lcdshadow
> > +     echo '1' >/proc/acpi/ibm/lcdshadow

> Hello! Is not the whole /proc/apci/ibm API for new things obsoleted or deprecated?
> And should not rather it use platform driver in /sys/ (class?) namespace?

There is an ongoing discussion about API to this kind of devices
somewhere in GPU mailing lists.
This interface is custom and probably shall never have been appeared.
However no-one prevented this from happening.

-- 
With Best Regards,
Andy Shevchenko


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