Re: [PATCH] ELAN touchpad i2c_hid bugs fix

[Kai-Heng Feng]

at 01:18, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:

> On Wed, Mar 20, 2019 at 6:55 PM Kai-Heng Feng
> <kai.heng.feng@xxxxxxxxxxxxx> wrote:
> > at 23:39, Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
> > > On 3/20/19 3:37 PM, Benjamin Tissoires wrote:
>
> > > Benjamin, what I find interesting here is that the BOGUS_IRQ quirk
> > > is also used on Elan devices, I suspect that these Elan devices
> > > likely also need the I2C_HID_QUIRK_FORCE_TRIGGER_FALLING quirk
> > > and then they probably will no longer need the bogus IRQ flag,
> > > if you know about bugreports with an acpidump for any of the devices
> > > needing the bogus IRQ quirk, then I (or you) can check how the IRQ is
> > > declared there, I suspect it will be declared as level-low, just like
> > > with the laptop this patch was written for. And it probably need to
> > > be edge-falling instead of level-low just like this case.
> >
> > First, Iâve already tried using IRQF_TRIGGER_FALLING, unfortunately it
> > doesnât solve the issue for me.
> >
> > I talked to Elan once, and they confirm the correct IRQ trigger is level
> > low. So forcing falling trigger may break other platforms.
>
> As far as I understood Vladislav the quirk he got from Elan as well.

Ok, then this is really weird.

> > Recently we found that Elan touchpad doesnât like GpioInt() from its _CRS.
> > Once the Interrupt() is used instead, the issue goes away.
>
> IIRC i2c core tries to get interrupt from Interrupt() resource and
> then falls back to GpioInt().
> See i2c_acpi_get_info() and i2c_device_probe().

Hereâs its ASL:

    Scope (\_SB.PCI0.I2C4)
    {
        Device (TPD0)
        {
            Name (_ADR, One)  // _ADR: Address
            Name (_HID, "DELL08AE")  // _HID: Hardware ID
            Name (_CID, "PNP0C50" /* HID Protocol Device (I2C bus) */)  // _CID: Compatible ID
            Name (_UID, One)  // _UID: Unique ID
            Name (_S0W, 0x04)  // _S0W: S0 Device Wake State
            Name (SBFB, ResourceTemplate ()
            {
                I2cSerialBusV2 (0x002C, ControllerInitiated, 0x00061A80,
                    AddressingMode7Bit, "\\_SB.PCI0.I2C4",
                    0x00, ResourceConsumer, , Exclusive,
                    )
            })
            Name (SBFG, ResourceTemplate ()
            {
                GpioInt (Level, ActiveLow, ExclusiveAndWake, PullUp, 0x0000,
                    "\\_SB.GPO1", 0x00, ResourceConsumer, ,
                    )
                    {   // Pin list
                        0x0012
                    }
            })
            Name (SBFI, ResourceTemplate ()
            {
                Interrupt (ResourceConsumer, Level, ActiveLow, ExclusiveAndWake, ,, )
                {
                    0x0000003C,
                }
            })
            Method (_INI, 0, NotSerialized)  // _INI: Initialize
            {
            }
            Method (_STA, 0, NotSerialized)  // _STA: Status
            {
                If ((TCPD == One))
                {
                    Return (0x0F)
                }

                Return (Zero)
            }
            Method (_CRS, 0, NotSerialized)  // _CRS: Current Resource Settings
            {
                If ((OSYS < 0x07DC))
                {
                    Return (SBFI) /* \_SB_.PCI0.I2C4.TPD0.SBFI */
                }

                Return (ConcatenateResTemplate (SBFB, SBFG))
            }
            Method (_DSM, 4, NotSerialized)  // _DSM: Device-Specific Method
            {
                If ((Arg0 == ToUUID ("3cdff6f7-4267-4555-ad05-b30a3d8938de") /* HID I2C Device */))
                {
                    If ((Arg2 == Zero))
                    {
                        If ((Arg1 == One))
                        {
                            Return (Buffer (One)
                            {
                                 0x03                                             // .
                            })
                        }
                        Else
                        {
                            Return (Buffer (One)
                            {
                                 0x00                                             // .
                            })
                        }
                    }
                    ElseIf ((Arg2 == One))
                    {
                        Return (0x20)
                    }
                    Else
                    {
                        Return (Buffer (One)
                        {
                             0x00                                             // .
                        })
                    }
                }
                ElseIf ((Arg0 == ToUUID ("ef87eb82-f951-46da-84ec-14871ac6f84b")))
                {
                    If ((Arg2 == Zero))
                    {
                        If ((Arg1 == One))
                        {
                            Return (Buffer (One)
                            {
                                 0x03                                             // .
                            })
                        }
                    }

                    If ((Arg2 == One))
                    {
                        Return (ConcatenateResTemplate (SBFB, SBFG))
                    }

                    Return (Buffer (One)
                    {
                         0x00                                             // .
                    })
                }
                }
                Else
                {
                    Return (Buffer (One)
                    {
                         0x00                                             // .
                    })
                }
            }
        }
    }

Change SBFG to SBFI in its _CRS can workaround the issue.
Is ASL in this form possible to do the flow you described?

Kai-Heng

> > But I am not sure how to patch its DSDT/SSDT in i2c-hid.
>
> --
> With Best Regards,
> Andy Shevchenko