Re: [PATCH v3 04/11] platform/x86: asus-wmi: Improve DSTS WMI method ID detection
On Thu, May 9, 2019 at 8:29 PM Yurii Pavlovskyi wrote: > On 08.05.19 15:36, Andy Shevchenko wrote:> On Fri, Apr 19, 2019 at 1:08 PM > Yurii Pavlovskyi > > wrote: > >> int rv; > >> + char *wmi_uid; > > > > Keep them in reversed spruce order. > > What do you mean by that? Do you mean like this? > + char *wmi_uid; > int rv; Yes. > int err; Don't see this in the above, though. > >> +#define ASUS_WMI_METHODID_DSTS 0x53544344 /* Device STatuS > (DCTS) */ > > > > It's not clear from the description what 'C' stands for. > > Is there any specification which describes the difference and actual > > abbreviations? > > > Not that I know of. Daniel had written some research in the previous > version thread regarding where it is used, but as I understand from current > implementation the functional difference is not really there, as it serves > the same purpose as DSTS, just for another hardware. > > On 09.05.19 08:08, Daniel Drake wrote: > > For clarity I think the constants could be renamed as > > ASUS_WMI_METHODID_DCTS and ASUS_WMI_METHODID_DSTS. > > > Agree, that'll be better. Also makes sense, but then fix up capitalization in the comment (perhaps "Device status" would be good in both cases). -- With Best Regards, Andy Shevchenko
Re: [PATCH v3 04/11] platform/x86: asus-wmi: Improve DSTS WMI method ID detection
On 08.05.19 15:36, Andy Shevchenko wrote:> On Fri, Apr 19, 2019 at 1:08 PM Yurii Pavlovskyi > wrote: >> int rv; >> + char *wmi_uid; > > Keep them in reversed spruce order. What do you mean by that? Do you mean like this? + char *wmi_uid; int rv; int err; >> +#define ASUS_WMI_METHODID_DSTS 0x53544344 /* Device STatuS (DCTS) */ > > It's not clear from the description what 'C' stands for. > Is there any specification which describes the difference and actual > abbreviations? > Not that I know of. Daniel had written some research in the previous version thread regarding where it is used, but as I understand from current implementation the functional difference is not really there, as it serves the same purpose as DSTS, just for another hardware. On 09.05.19 08:08, Daniel Drake wrote: > For clarity I think the constants could be renamed as > ASUS_WMI_METHODID_DCTS and ASUS_WMI_METHODID_DSTS. > Agree, that'll be better. Thanks, Yurii
Re: [PATCH v3 04/11] platform/x86: asus-wmi: Improve DSTS WMI method ID detection
> > -#define ASUS_WMI_METHODID_DSTS 0x53544344 /* Device STatuS */ > > -#define ASUS_WMI_METHODID_DSTS20x53545344 /* Device STatuS > > #2*/ > > > +#define ASUS_WMI_METHODID_DSTS 0x53544344 /* Device STatuS (DCTS) > > */ > > It's not clear from the description what 'C' stands for. > Is there any specification which describes the difference and actual > abbreviations? The (recent) spec I have here doesn't mention 0x53544344 (DCTS). However the spec changelog does mention that EEEPC stuff was removed from the spec a while ago. The spec does mention 0x53545344 (DSTS), labelled as "Get device status". For clarity I think the constants could be renamed as ASUS_WMI_METHODID_DCTS and ASUS_WMI_METHODID_DSTS. Daniel
Re: [PATCH v3 04/11] platform/x86: asus-wmi: Improve DSTS WMI method ID detection
On Fri, Apr 19, 2019 at 1:08 PM Yurii Pavlovskyi
wrote:
>
> The DSTS method detection mistakenly selects DCTS instead of DSTS if
> nothing is returned when the method ID is not defined in WMNB. As a result,
> the control of keyboard backlight is not functional for TUF Gaming series
> laptops. Implement another detection method instead.
>
> There is evidence that DCTS is handled by ACPI WMI devices that have _UID
> ASUSWMI, whereas none of the devices without ASUSWMI respond to DCTS and
> DSTS is used instead [1]. To check the _UID a new method is added to wmi.h
> / wmi.c. It returns _UID of the ACPI WMI device that declares WMI object
> with given GUID.
>
> Generally, it is possible that multiple PNP0C14 ACPI devices are present in
> the system as mentioned in the commit message of commit bff431e49ff5
> ("ACPI: WMI: Add ACPI-WMI mapping driver").
>
> Therefore the _UID is checked for given GUID that maps to a specific ACPI
> device, to which it is also mapped by other methods of wmi module.
>
> DSDT examples:
>
> FX505GM:
> Method (WMNB, 3, Serialized)
> { ...
> If ((Local0 == 0x53545344))
> {
> ...
> Return (Zero)
> }
> ...
> // No return
> }
>
> K54C:
> Method (WMNB, 3, Serialized)
> { ...
> If ((Local0 == 0x53545344))
> {
> ...
> Return (0x02)
> }
> ...
> Return (0xFFFE)
> }
>
> [1] https://lkml.org/lkml/2019/4/11/322
Link: ...?
> int rv;
> + char *wmi_uid;
Keep them in reversed spruce order.
> + if (!strcmp(wmi_uid, ASUS_ACPI_UID_ASUSWMI)) {
> + pr_info("Detected ASUSWMI, use DCTS\n");
dev_info()?
> asus->dsts_id = ASUS_WMI_METHODID_DSTS;
> - else
> + } else {
> + pr_info("Detected %s, not ASUSWMI, use DSTS\n", wmi_uid);
Ditto.
> --- a/drivers/platform/x86/wmi.c
> +++ b/drivers/platform/x86/wmi.c
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
This change should go separately.
> -#define ASUS_WMI_METHODID_DSTS 0x53544344 /* Device STatuS */
> -#define ASUS_WMI_METHODID_DSTS20x53545344 /* Device STatuS
> #2*/
> +#define ASUS_WMI_METHODID_DSTS 0x53544344 /* Device STatuS (DCTS) */
It's not clear from the description what 'C' stands for.
Is there any specification which describes the difference and actual
abbreviations?
> +#define ASUS_WMI_METHODID_DSTS20x53545344 /* Device STatuS
> (DSTS) */
--
With Best Regards,
Andy Shevchenko
[PATCH v3 04/11] platform/x86: asus-wmi: Improve DSTS WMI method ID detection
The DSTS method detection mistakenly selects DCTS instead of DSTS if
nothing is returned when the method ID is not defined in WMNB. As a result,
the control of keyboard backlight is not functional for TUF Gaming series
laptops. Implement another detection method instead.
There is evidence that DCTS is handled by ACPI WMI devices that have _UID
ASUSWMI, whereas none of the devices without ASUSWMI respond to DCTS and
DSTS is used instead [1]. To check the _UID a new method is added to wmi.h
/ wmi.c. It returns _UID of the ACPI WMI device that declares WMI object
with given GUID.
Generally, it is possible that multiple PNP0C14 ACPI devices are present in
the system as mentioned in the commit message of commit bff431e49ff5
("ACPI: WMI: Add ACPI-WMI mapping driver").
Therefore the _UID is checked for given GUID that maps to a specific ACPI
device, to which it is also mapped by other methods of wmi module.
DSDT examples:
FX505GM:
Method (WMNB, 3, Serialized)
{ ...
If ((Local0 == 0x53545344))
{
...
Return (Zero)
}
...
// No return
}
K54C:
Method (WMNB, 3, Serialized)
{ ...
If ((Local0 == 0x53545344))
{
...
Return (0x02)
}
...
Return (0xFFFE)
}
[1] https://lkml.org/lkml/2019/4/11/322
Signed-off-by: Yurii Pavlovskyi
Suggested-by: Daniel Drake
---
drivers/platform/x86/asus-wmi.c| 20 ++--
drivers/platform/x86/wmi.c | 19 +++
include/linux/acpi.h | 1 +
include/linux/platform_data/x86/asus-wmi.h | 4 ++--
4 files changed, 40 insertions(+), 4 deletions(-)
diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index ba04737ece0d..266d0eda5476 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -80,6 +80,8 @@ MODULE_LICENSE("GPL");
#define USB_INTEL_XUSB2PR 0xD0
#define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI 0x9c31
+#define ASUS_ACPI_UID_ASUSWMI "ASUSWMI"
+
static const char * const ashs_ids[] = { "ATK4001", "ATK4002", NULL };
static bool ashs_present(void)
@@ -1847,6 +1849,7 @@ static int asus_wmi_sysfs_init(struct platform_device
*device)
static int asus_wmi_platform_init(struct asus_wmi *asus)
{
int rv;
+ char *wmi_uid;
/* INIT enable hotkeys on some models */
if (!asus_wmi_evaluate_method(ASUS_WMI_METHODID_INIT, 0, 0, ))
@@ -1875,11 +1878,24 @@ static int asus_wmi_platform_init(struct asus_wmi *asus)
* Note, on most Eeepc, there is no way to check if a method exist
* or note, while on notebooks, they returns 0xFFFE on failure,
* but once again, SPEC may probably be used for that kind of things.
+*
+* Additionally at least TUF Gaming series laptops return nothing for
+* unknown methods, so the detection in this way is not possible.
+*
+* There is strong indication that only ACPI WMI devices that have _UID
+* equal to "ASUSWMI" use DCTS whereas those with "ATK" use DSTS.
*/
- if (!asus_wmi_evaluate_method(ASUS_WMI_METHODID_DSTS, 0, 0, NULL))
+ wmi_uid = wmi_get_acpi_device_uid(ASUS_WMI_MGMT_GUID);
+ if (!wmi_uid)
+ return -ENODEV;
+
+ if (!strcmp(wmi_uid, ASUS_ACPI_UID_ASUSWMI)) {
+ pr_info("Detected ASUSWMI, use DCTS\n");
asus->dsts_id = ASUS_WMI_METHODID_DSTS;
- else
+ } else {
+ pr_info("Detected %s, not ASUSWMI, use DSTS\n", wmi_uid);
asus->dsts_id = ASUS_WMI_METHODID_DSTS2;
+ }
/* CWAP allow to define the behavior of the Fn+F2 key,
* this method doesn't seems to be present on Eee PCs */
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
index 7b26b6ccf1a0..b08ffb769cbe 100644
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -635,6 +635,25 @@ bool wmi_has_guid(const char *guid_string)
}
EXPORT_SYMBOL_GPL(wmi_has_guid);
+/**
+ * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID
+ * @guid_string: 36 char string of the form
fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ *
+ * Find the _UID of ACPI device associated with this WMI GUID.
+ *
+ * Return: The ACPI _UID field value or NULL if the WMI GUID was not found
+ */
+char *wmi_get_acpi_device_uid(const char *guid_string)
+{
+ struct wmi_block *wblock = NULL;
+
+ if (!find_guid(guid_string, ))
+ return NULL;
+
+ return acpi_device_uid(wblock->acpi_device);
+}
+EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
+
static struct wmi_block *dev_to_wblock(struct device *dev)
{
return container_of(dev, struct wmi_block, dev.dev);
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index d5dcebd7aad3..d31c7fd66f97 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -376,6 +376,7 @@ extern acpi_status wmi_install_notify_handler(const char
*guid,
extern
