Re: [PATCH v2 1/1] platform/x86: asus-wmi: disable USB0 hub on ROG Ally before suspend

[Luke Jones <luke@ljones.dev>]

On Mon, Nov 27 2023 at 11:39:09 PM +01:00:00, Hans de Goede 
<hdegoede@redhat.com> wrote:
> Hi,
> 
> On 11/27/23 21:17, Luke Jones wrote:
>> 
>> 
>>  On Mon, Nov 27 2023 at 09:53:13 AM +01:00:00, Hans de Goede 
>> <hdegoede@redhat.com> wrote:
>>>  Hi,
>>> 
>>>  On 11/27/23 00:05, Luke D. Jones wrote:
>>>>   ASUS have worked around an issue in XInput where it doesn't 
>>>> support USB
>>>>   selective suspend, which causes suspend issues in Windows. They 
>>>> worked
>>>>   around this by adjusting the MCU firmware to disable the USB0 
>>>> hub when
>>>>   the screen is switched off during the Microsoft DSM suspend path 
>>>> in ACPI.
>>>> 
>>>>   The issue we have with this however is one of timing - the call 
>>>> the tells
>>>>   the MCU to this isn't able to complete before suspend is done so 
>>>> we call
>>>>   this in a prepare() and add a small msleep() to ensure it is 
>>>> done. This
>>>>   must be done before the screen is switched off to prevent a 
>>>> variety of
>>>>   possible races.
>>>> 
>>>>   Further to this the MCU powersave option must also be disabled 
>>>> as it can
>>>>   cause a number of issues such as:
>>>>   - unreliable resume connection of N-Key
>>>>   - complete loss of N-Key if the power is plugged in while 
>>>> suspended
>>>>   Disabling the powersave option prevents this.
>>>> 
>>>>   Without this the MCU is unable to initialise itself correctly on 
>>>> resume.
>>>> 
>>>>   Signed-off-by: Luke D. Jones <luke@ljones.dev>
>>> 
>>>  Thanks, patch looks good to me, except that all the new lines
>>>  seem to use 4 spaces rather then a tab char as indent.
>> 
>>  Apologies for the previous HTML email.
>>  I must be going mad... are you sure? I've checked the patch file I 
>> submitted. Run checkpatch on it. Checked my email copy, and checked 
>> in lore... I can't see where space chars are?
> 
> So I just checked the copy in patchwork:
> 
> https://patchwork.kernel.org/project/platform-driver-x86/patch/20231126230521.125708-2-luke@ljones.dev/
> 
> and you are rights, no 4 spaces there.
> 
> Where as if you look further down in this reply, where the original
> patch is quoted the 4 spaces are right there, so now I'm wondering
> if maybe my mail client introduced the problem when I was replying ?
> 
> (replies to other patches preserve the tabs just fine).
> 
> So this is weird, but lets just forget about it, just some weird
> glitch ...
> 

Sun flares and cosmic particles.

I'm comfortable with this being merged and doing through stable also. I 
did many many more tests this morning, along with a half dozen other 
people and this solution appears to be the only reliable option. When 
ASUS provide a way to turn off the MCU unplug feature I will update 
with a new patch (and add the TODO).

> 
> 
> 
>> 
>>> 
>>>  With that fixed you can add my:
>>> 
>>>  Reviewed-by: Hans de Goede <hdegoede@redhat.com>
>>> 
>>>  to the next version.
>>> 
>>>  Regards,
>>> 
>>>  Hans
>>> 
>>> 
>>>>   ---
>>>>    drivers/platform/x86/asus-wmi.c            | 50 
>>>> ++++++++++++++++++++++
>>>>    include/linux/platform_data/x86/asus-wmi.h |  3 ++
>>>>    2 files changed, 53 insertions(+)
>>>> 
>>>>   diff --git a/drivers/platform/x86/asus-wmi.c 
>>>> b/drivers/platform/x86/asus-wmi.c
>>>>   index 6a79f16233ab..4ba33dfebfd4 100644
>>>>   --- a/drivers/platform/x86/asus-wmi.c
>>>>   +++ b/drivers/platform/x86/asus-wmi.c
>>>>   @@ -16,6 +16,7 @@
>>>>    #include <linux/acpi.h>
>>>>    #include <linux/backlight.h>
>>>>    #include <linux/debugfs.h>
>>>>   +#include <linux/delay.h>
>>>>    #include <linux/dmi.h>
>>>>    #include <linux/fb.h>
>>>>    #include <linux/hwmon.h>
>>>>   @@ -132,6 +133,11 @@ module_param(fnlock_default, bool, 0444);
>>>>    #define ASUS_SCREENPAD_BRIGHT_MAX 255
>>>>    #define ASUS_SCREENPAD_BRIGHT_DEFAULT 60
>>>> 
>>>>   +/* Controls the power state of the USB0 hub on ROG Ally which 
>>>> input is on */
>>>>   +#define ASUS_USB0_PWR_EC0_CSEE "\\_SB.PCI0.SBRG.EC0.CSEE"
>>>>   +/* 300ms so far seems to produce a reliable result on AC and 
>>>> battery */
>>>>   +#define ASUS_USB0_PWR_EC0_CSEE_WAIT 300
>>>>   +
>>>>    static const char * const ashs_ids[] = { "ATK4001", "ATK4002", 
>>>> NULL };
>>>> 
>>>>    static int throttle_thermal_policy_write(struct asus_wmi *);
>>>>   @@ -300,6 +306,9 @@ struct asus_wmi {
>>>> 
>>>>        bool fnlock_locked;
>>>> 
>>>>   +    /* The ROG Ally device requires the MCU USB device be 
>>>> disconnected before suspend */
>>>>   +    bool ally_mcu_usb_switch;
>>>>   +
>>>>        struct asus_wmi_debug debug;
>>>> 
>>>>        struct asus_wmi_driver *driver;
>>>>   @@ -4488,6 +4497,8 @@ static int asus_wmi_add(struct 
>>>> platform_device *pdev)
>>>>        asus->nv_temp_tgt_available = asus_wmi_dev_is_present(asus, 
>>>> ASUS_WMI_DEVID_NV_THERM_TARGET);
>>>>        asus->panel_overdrive_available = 
>>>> asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_PANEL_OD);
>>>>        asus->mini_led_mode_available = 
>>>> asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_MINI_LED_MODE);
>>>>   +    asus->ally_mcu_usb_switch = acpi_has_method(NULL, 
>>>> ASUS_USB0_PWR_EC0_CSEE)
>>>>   +                        && dmi_match(DMI_BOARD_NAME, "RC71L");
>>>> 
>>>>        err = fan_boost_mode_check_present(asus);
>>>>        if (err)
>>>>   @@ -4654,6 +4665,43 @@ static int asus_hotk_resume(struct device 
>>>> *device)
>>>>            asus_wmi_fnlock_update(asus);
>>>> 
>>>>        asus_wmi_tablet_mode_get_state(asus);
>>>>   +
>>>>   +    return 0;
>>>>   +}
>>>>   +
>>>>   +static int asus_hotk_resume_early(struct device *device)
>>>>   +{
>>>>   +    struct asus_wmi *asus = dev_get_drvdata(device);
>>>>   +
>>>>   +    if (asus->ally_mcu_usb_switch) {
>>>>   +        if (ACPI_FAILURE(acpi_execute_simple_method(NULL, 
>>>> ASUS_USB0_PWR_EC0_CSEE, 0xB8)))
>>>>   +            dev_err(device, "ROG Ally MCU failed to connect USB 
>>>> dev\n");
>>>>   +        else
>>>>   +            msleep(ASUS_USB0_PWR_EC0_CSEE_WAIT);
>>>>   +    }
>>>>   +    return 0;
>>>>   +}
>>>>   +
>>>>   +static int asus_hotk_prepare(struct device *device)
>>>>   +{
>>>>   +    struct asus_wmi *asus = dev_get_drvdata(device);
>>>>   +    int result, err;
>>>>   +
>>>>   +    if (asus->ally_mcu_usb_switch) {
>>>>   +        /* When powersave is enabled it causes many issues with 
>>>> resume of USB hub */
>>>>   +        result = asus_wmi_get_devstate_simple(asus, 
>>>> ASUS_WMI_DEVID_MCU_POWERSAVE);
>>>>   +        if (result == 1) {
>>>>   +            dev_warn(device, "MCU powersave enabled, disabling 
>>>> to prevent resume issues");
>>>>   +            err = 
>>>> asus_wmi_set_devstate(ASUS_WMI_DEVID_MCU_POWERSAVE, 0, &result);
>>>>   +            if (err || result != 1)
>>>>   +                dev_err(device, "Failed to set MCU powersave 
>>>> mode: %d\n", err);
>>>>   +        }
>>>>   +        /* sleep required to ensure USB0 is disabled before 
>>>> sleep continues */
>>>>   +        if (ACPI_FAILURE(acpi_execute_simple_method(NULL, 
>>>> ASUS_USB0_PWR_EC0_CSEE, 0xB7)))
>>>>   +            dev_err(device, "ROG Ally MCU failed to disconnect 
>>>> USB dev\n");
>>>>   +        else
>>>>   +            msleep(ASUS_USB0_PWR_EC0_CSEE_WAIT);
>>>>   +    }
>>>>        return 0;
>>>>    }
>>>> 
>>>>   @@ -4701,6 +4749,8 @@ static const struct dev_pm_ops asus_pm_ops 
>>>> = {
>>>>        .thaw = asus_hotk_thaw,
>>>>        .restore = asus_hotk_restore,
>>>>        .resume = asus_hotk_resume,
>>>>   +    .resume_early = asus_hotk_resume_early,
>>>>   +    .prepare = asus_hotk_prepare,
>>>>    };
>>>> 
>>>>    /* Registration 
>>>> ***************************************************************/
>>>>   diff --git a/include/linux/platform_data/x86/asus-wmi.h 
>>>> b/include/linux/platform_data/x86/asus-wmi.h
>>>>   index 63e630276499..ab1c7deff118 100644
>>>>   --- a/include/linux/platform_data/x86/asus-wmi.h
>>>>   +++ b/include/linux/platform_data/x86/asus-wmi.h
>>>>   @@ -114,6 +114,9 @@
>>>>    /* Charging mode - 1=Barrel, 2=USB */
>>>>    #define ASUS_WMI_DEVID_CHARGE_MODE    0x0012006C
>>>> 
>>>>   +/* MCU powersave mode */
>>>>   +#define ASUS_WMI_DEVID_MCU_POWERSAVE   0x001200E2
>>>>   +
>>>>    /* epu is connected? 1 == true */
>>>>    #define ASUS_WMI_DEVID_EGPU_CONNECTED    0x00090018
>>>>    /* egpu on/off */
>>> 
>> 
>> 
>