RE: [PATCH] ELAN touchpad i2c_hid bugs fix

From: Mario.Limonciello
Date: Mon Apr 01 2019 - 17:38:09 EST


> -----Original Message-----
> From: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Sent: Thursday, March 21, 2019 4:48 AM
> To: Kai-Heng Feng; Limonciello, Mario
> Cc: Hans de Goede; Benjamin Tissoires; hotwater438@xxxxxxxxxxxx; Jiri Kosina;
> Stephen Boyd; Sebastian Andrzej Siewior; Dmitry Torokhov; open list:HID CORE
> LAYER; lkml
> Subject: Re: [PATCH] ELAN touchpad i2c_hid bugs fix
>
>
> [EXTERNAL EMAIL]
>
> +Cc: Mario
>
> Mario, do you have any insights about the issue with touchpad on Dell
> system described below?

My apologies, this got lost while I was on vacation.

>
> On Thu, Mar 21, 2019 at 6:08 AM Kai-Heng Feng
> <kai.heng.feng@xxxxxxxxxxxxx> wrote:
> >
> > 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.

Is this pre-production HW? If so, maybe this is a case that we should talk
about custom OSI string to run the ASL differently.

The other option would be to create a new ASL method in FW and from Linux
side a quirk that calls this new ASL method.