On Wednesday, November 21, 2018 11:37:22 AM CET Hans de Goede wrote:
> HI,
>
> On 19-11-18 19:06, Hans de Goede wrote:
> > Many HP AMD based laptops contain an SMB0001 device like this:
> >
> > Device (SMBD)
> > {
> > Name (_HID, "SMB0001") // _HID: Hardware ID
> > Name (_CRS, ResourceTemplate () // _CRS: Current Resource Settings
> > {
> > IO (Decode16,
> > 0x0B20, // Range Minimum
> > 0x0B20, // Range Maximum
> > 0x20, // Alignment
> > 0x20, // Length
> > )
> > IRQ (Level, ActiveLow, Shared, )
> > {7}
> > })
> > }
> >
> > The legacy style IRQ resource here causes acpi_dev_get_irqresource() to
> > be called with legacy=true and this message to show in dmesg:
> > ACPI: IRQ 7 override to edge, high
> >
> > This causes issues when later on the AMD0030 GPIO device gets enumerated:
> >
> > Device (GPIO)
> > {
> > Name (_HID, "AMDI0030") // _HID: Hardware ID
> > Name (_CID, "AMDI0030") // _CID: Compatible ID
> > Name (_UID, Zero) // _UID: Unique ID
> > Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings
> > {
> > Name (RBUF, ResourceTemplate ()
> > {
> > Interrupt (ResourceConsumer, Level, ActiveLow, Shared, ,, )
> > {
> > 0x00000007,
> > }
> > Memory32Fixed (ReadWrite,
> > 0xFED81500, // Address Base
> > 0x00000400, // Address Length
> > )
> > })
> > Return (RBUF) /* \_SB_.GPIO._CRS.RBUF */
> > }
> > }
> >
> > Now acpi_dev_get_irqresource() gets called with legacy=false, but because
> > of the earlier override of the trigger-type acpi_register_gsi() returns
> > -EBUSY (because we try to register the same interrupt with a different
> > trigger-type) and we end up setting IORESOURCE_DISABLED in the flags.
> >
> > The setting of IORESOURCE_DISABLED causes platform_get_irq() to call
> > acpi_irq_get() which is not implemented on x86 and returns -EINVAL.
> > resulting in the following in dmesg:
> >
> > amd_gpio AMDI0030:00: Failed to get gpio IRQ: -22
> > amd_gpio: probe of AMDI0030:00 failed with error -22
> >
> > The SMB0001 is a "virtual" device in the sense that the only way the OS
> > interacts with it is through calling a couple of methods to do SMBus
> > transfers. As such it is weird that it has IO and IRQ resources at all,
> > because the driver for it is not expected to ever access the hardware
> > directly.
> >
> > The Linux driver for the SMB0001 device directly binds to the acpi_device
> > through the acpi_bus, so we do not need to instantiate a platform_device
> > for this ACPI device. This commit adds the SMB0001 HID to the
> > forbidden_id_list, avoiding the instantiating of a platform_device for it.
> > Not instantiating a platform_device means we will no longer call
> > acpi_dev_get_irqresource() for the legacy IRQ resource fixing the probe of
> > the AMDI0030 device failing.
> >
> > BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1644013
> > BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=198715
> > BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199523
> > Reported-by: Lukas Kahnert <openproggerfreak@xxxxxxxxx>
> > Tested-by: Marc <suaefar@xxxxxxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
> > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
>
> A quick status update on this, I've got confirmation from 4 different users
> that this fixes the touchscreen not working on various models AMD based
> HP laptops.
>
> As such it would be nice to get this into 4.20 as a bugfix.
I'm going to queue it up.
Thanks,
Rafael
