Re: [PATCH] thinkpad_acpi: Add support for X1 Yoga (2016) Tablet Mode

[Lyude Paul <lyude@redhat.com>]

as well, can someone confirm this patch made it to the ibm-acpi-devel
list? When I originally sent this I realized I wasn't subscribed to the
list, so I'm guessing I might need to resend.

On Tue, 2016-10-25 at 18:12 -0400, Lyude wrote:
> For whatever reason, the X1 Yoga doesn't support the normal method of
> querying for tablet mode. Instead of providing the MHKG method under
> the
> hotkey handle, we're instead given the CMMD method under the EC
> handle.
> Values on this handle are either 0x1, laptop mode, or 0x6, tablet
> mode.
> 
> Signed-off-by: Lyude <lyude@redhat.com>
> ---
> So HOPEFULLY I actually did this right. There was some discussion
> here
> previously about supporting this, and it was previously mentioned
> that the IOST
> method was responsible for holding the current tablet status.
> However, it
> really doesn't seem like this is the case:
> 
>     Method (_Q2E, 0, NotSerialized)  // _Qxx: EC Query
>     {
> 	Local0 = \_SB.PCI0.LPC.EC.CMMD
> 	If ((Local0 != 0x00) && (Local0 <= 0x06))
> 	{
> 	    If (Local0 != \PMMD)
> 	    {
> 		\PMMD = Local0
> 		\_SB.PCI0.LPC.EC.HKEY.MHKQ (0x60C0)
> 	    }
> 	}
> 
> 	If ((Local0 == 0x00) || (Local0 >= 0x07))
> 	{
> 	    Local1 = 0x01
> 	}
> 	ElseIf ((Local0 == 0x02) || (Local0 == 0x03))
> 	{
> 	    Local1 = 0x02
> 	}
> 	Else
> 	{
> 	    Local1 = 0x03
> 	}
> 
> 	If (Local1 != \LVMD)
> 	{
> 	    \LVMD = Local1
> 	    Sleep (0x0A)
> 	    \_SB.PCI0.LPC.EC.HKEY.MHKQ (0x60F0)
> 	}
>     }
> 
> IOST seems to be present in the decompiled DSDT from my Yoga, however
> it's
> quite far from the spot that actually sends the 0x60C0 hotkey event.
> Let me
> know if you guys want to verify this against the full decompiled DSDT
> for this
> machine.
> 
>  drivers/platform/x86/thinkpad_acpi.c | 36
> +++++++++++++++++++++++++++++++++---
>  1 file changed, 33 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/platform/x86/thinkpad_acpi.c
> b/drivers/platform/x86/thinkpad_acpi.c
> index b65ce75..8082dc9 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -190,6 +190,9 @@ enum tpacpi_hkey_event_t {
>  	TP_HKEY_EV_LID_OPEN		= 0x5002, /* laptop lid
> opened */
>  	TP_HKEY_EV_TABLET_TABLET	= 0x5009, /* tablet swivel
> up */
>  	TP_HKEY_EV_TABLET_NOTEBOOK	= 0x500a, /* tablet swivel
> down */
> +	TP_HKEY_EV_TABLET_CHANGED	= 0x60c0, /* X1 Yoga
> (2016):
> +						   * enter/leave
> tablet mode
> +						   */
>  	TP_HKEY_EV_PEN_INSERTED		= 0x500b, /* tablet
> pen inserted */
>  	TP_HKEY_EV_PEN_REMOVED		= 0x500c, /* tablet
> pen removed */
>  	TP_HKEY_EV_BRGHT_CHANGED	= 0x5010, /* backlight
> control event */
> @@ -303,6 +306,7 @@ static struct {
>  	u32 hotkey_mask:1;
>  	u32 hotkey_wlsw:1;
>  	u32 hotkey_tablet:1;
> +	u32 hotkey_tablet_cmmd:1;
>  	u32 kbdlight:1;
>  	u32 light:1;
>  	u32 light_status:1;
> @@ -2059,6 +2063,8 @@ static void hotkey_poll_setup(const bool
> may_warn);
>  
>  /* HKEY.MHKG() return bits */
>  #define TP_HOTKEY_TABLET_MASK (1 << 3)
> +/* ThinkPad X1 Yoga (2016) */
> +#define TP_EC_CMMD_TABLET_MODE 0x6
>  
>  static int hotkey_get_wlsw(void)
>  {
> @@ -2083,10 +2089,18 @@ static int hotkey_get_tablet_mode(int
> *status)
>  {
>  	int s;
>  
> -	if (!acpi_evalf(hkey_handle, &s, "MHKG", "d"))
> -		return -EIO;
> +	if (tp_features.hotkey_tablet_cmmd) {
> +		if (!acpi_evalf(ec_handle, &s, "CMMD", "d"))
> +			return -EIO;
> +
> +		*status = (s == TP_EC_CMMD_TABLET_MODE);
> +	} else {
> +		if (!acpi_evalf(hkey_handle, &s, "MHKG", "d"))
> +			return -EIO;
> +
> +		*status = ((s & TP_HOTKEY_TABLET_MASK) != 0);
> +	}
>  
> -	*status = ((s & TP_HOTKEY_TABLET_MASK) != 0);
>  	return 0;
>  }
>  
> @@ -3475,6 +3489,18 @@ static int __init hotkey_init(struct
> ibm_init_struct *iibm)
>  				&dev_attr_hotkey_tablet_mode.attr);
>  	}
>  
> +	/* For X1 Yoga (2016) */
> +	if (!res && acpi_evalf(ec_handle, &status, "CMMD", "qd")) {
> +		tp_features.hotkey_tablet = 1;
> +		tp_features.hotkey_tablet_cmmd = 1;
> +		tabletsw_state = (status == TP_EC_CMMD_TABLET_MODE);
> +
> +		pr_info("Possible tablet mode switch found; ThinkPad
> in %s mode\n",
> +			(tabletsw_state) ? "tablet" : "laptop");
> +		res = add_to_attr_set(hotkey_dev_attributes,
> +				      &dev_attr_hotkey_tablet_mode.a
> ttr);
> +	}
> +
>  	if (!res)
>  		res = register_attr_set_with_sysfs(
>  				hotkey_dev_attributes,
> @@ -3899,6 +3925,10 @@ static bool hotkey_notify_6xxx(const u32 hkey,
>  		*ignore_acpi_ev = true;
>  		return true;
>  
> +	case TP_HKEY_EV_TABLET_CHANGED:
> +		tpacpi_input_send_tabletsw();
> +		break;
> +
>  	default:
>  		pr_warn("unknown possible thermal alarm or keyboard
> event received\n");
>  		known = false;