Re: [PATCH 1/9] platform/x86: asus-wmi: add support for 2024 ROG Mini-LED

[Luke Jones]

On Tue, 26 Mar 2024, at 2:47 AM, Ilpo Järvinen wrote:
> On Mon, 25 Mar 2024, Luke D. Jones wrote:
> 
> > Support the 2024 mini-led backlight and adjust the related functions
> > to select the relevant dev-id. Also add `available_mini_led_mode` to the
> > platform sysfs since the available mini-led levels can be different.
> > 
> > Signed-off-by: Luke D. Jones <luke@xxxxxxxxxx>
> > ---
> >  .../ABI/testing/sysfs-platform-asus-wmi       |  8 ++
> >  drivers/platform/x86/asus-wmi.c               | 74 +++++++++++++++++--
> >  include/linux/platform_data/x86/asus-wmi.h    |  1 +
> >  3 files changed, 76 insertions(+), 7 deletions(-)
> > 
> > diff --git a/Documentation/ABI/testing/sysfs-platform-asus-wmi b/Documentation/ABI/testing/sysfs-platform-asus-wmi
> > index 8a7e25bde085..61a745d2476f 100644
> > --- a/Documentation/ABI/testing/sysfs-platform-asus-wmi
> > +++ b/Documentation/ABI/testing/sysfs-platform-asus-wmi
> > @@ -126,6 +126,14 @@ Description:
> >  Change the mini-LED mode:
> >  * 0 - Single-zone,
> >  * 1 - Multi-zone
> > + * 2 - Multi-zone strong (available on newer generation mini-led)
> > +
> > +What: /sys/devices/platform/<platform>/available_mini_led_mode
> > +Date: Jun 2023
> > +KernelVersion: 6.10
> > +Contact: "Luke Jones" <luke@xxxxxxxxxx>
> > +Description:
> > + List the available mini-led modes.
> >  
> >  What: /sys/devices/platform/<platform>/ppt_pl1_spl
> >  Date: Jun 2023
> > diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
> > index 18be35fdb381..54ce0fb26f42 100644
> > --- a/drivers/platform/x86/asus-wmi.c
> > +++ b/drivers/platform/x86/asus-wmi.c
> > @@ -297,6 +297,7 @@ struct asus_wmi {
> >  
> >  bool panel_overdrive_available;
> >  bool mini_led_mode_available;
> > + u32 mini_led_dev_id;
> >  
> >  struct hotplug_slot hotplug_slot;
> >  struct mutex hotplug_lock;
> > @@ -2109,10 +2110,27 @@ static ssize_t mini_led_mode_show(struct device *dev,
> >  struct asus_wmi *asus = dev_get_drvdata(dev);
> >  int result;
> >  
> > - result = asus_wmi_get_devstate_simple(asus, ASUS_WMI_DEVID_MINI_LED_MODE);
> > - if (result < 0)
> > - return result;
> > + result = asus_wmi_get_devstate_simple(asus, asus->mini_led_dev_id);
> >  
> > + /* Remap the mode values to match previous generation mini-led.
> > + * Some BIOSes return -19 instead of 2, which is "mini-LED off", this
> > + * appears to be a  BIOS bug.
> > + */
> > + if (asus->mini_led_dev_id == ASUS_WMI_DEVID_MINI_LED_MODE2) {
> > + switch (result) {
> > + case 0:
> > + result = 1;
> > + break;
> > + case 1:
> > + result = 2;
> > + break;
> > + case 2:
> > + case -19:
> 
> Can you confirm this -19 really does come from BIOS? Because I suspect 
> it's -ENODEV error code from from one of the functions on the driver side
> (which is why I asked you to change it into -ENODEV).

Yes it does. It is rather annoying. What happens in this case is that `2` is written to the WMI endpoint to turn off the MINI-Led feature, this works fine and it is turned off, there are no errors from the write at all - verifying the accepted limits in dsdt also shows it is correct.

However, after that, the read fails once. And only if that `2` was written. `0` and `1` write fine, and read fine also. I hope I've managed to describe and clarify what I'm seeing here.

I'm happy to change -ENODEV. No problem, queued on my todo list.

Cheers,
Luke.