[v2,1/2] platform: Fix device check for surfacepro3_button
diff mbox series

Message ID 20190702003740.75970-2-luzmaximilian@gmail.com
State Superseded
Headers show
Series
  • Support for buttons on newer MS Surface devices
Related show

Commit Message

Maximilian Luz July 2, 2019, 12:37 a.m. UTC
Do not use the surfacepro3_button driver on newer Microsoft Surface
models, only use it on the Surface Pro 3 and 4. Newer models (5th, 6th
and possibly future generations) use the same device as the Surface Pro
4 to represent their volume and power buttons (MSHW0040), but their
acutal implementation is significantly different. This patch ensures
that the surfacepro3_button driver is only used on the Pro 3 and 4
models, allowing a different driver to bind on other models.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
---
 drivers/platform/x86/surfacepro3_button.c | 38 +++++++++++++++++++++++
 1 file changed, 38 insertions(+)

Comments

Chen Yu July 2, 2019, 1:14 a.m. UTC | #1
Hi,
On Tue, Jul 02, 2019 at 02:37:39AM +0200, Maximilian Luz wrote:
> Do not use the surfacepro3_button driver on newer Microsoft Surface
> models, only use it on the Surface Pro 3 and 4. Newer models (5th, 6th
> and possibly future generations) use the same device as the Surface Pro
> 4 to represent their volume and power buttons (MSHW0040), but their
> acutal implementation is significantly different. This patch ensures
> that the surfacepro3_button driver is only used on the Pro 3 and 4
> models, allowing a different driver to bind on other models.
>
This method overall looks ok to me.
> Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
> ---
>  drivers/platform/x86/surfacepro3_button.c | 38 +++++++++++++++++++++++
>  1 file changed, 38 insertions(+)
> 
> diff --git a/drivers/platform/x86/surfacepro3_button.c b/drivers/platform/x86/surfacepro3_button.c
> index 47c6d000465a..0e2c7dfafd9f 100644
> --- a/drivers/platform/x86/surfacepro3_button.c
> +++ b/drivers/platform/x86/surfacepro3_button.c
> @@ -20,6 +20,12 @@
>  #define SURFACE_BUTTON_OBJ_NAME		"VGBI"
>  #define SURFACE_BUTTON_DEVICE_NAME	"Surface Pro 3/4 Buttons"
>  
> +#define MSHW0040_DSM_REVISION		0x01
> +#define MSHW0040_DSM_GET_OMPR		0x02	// get OEM Platform Revision
> +static const guid_t MSHW0040_DSM_UUID =
> +	GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
> +		  0x49, 0x80, 0x35);
> +
>  #define SURFACE_BUTTON_NOTIFY_TABLET_MODE	0xc8
>  
>  #define SURFACE_BUTTON_NOTIFY_PRESS_POWER	0xc6
> @@ -142,6 +148,34 @@ static int surface_button_resume(struct device *dev)
>  }
>  #endif
>  
> +/*
> + * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device
> + * ID (MSHW0040) for the power/volume buttons. Make sure this is the right
> + * device by checking for the _DSM method and OEM Platform Revision.
> + */
> +static int surface_button_check_MSHW0040(struct acpi_device *dev)
> +{
> +	acpi_handle handle = dev->handle;
> +	union acpi_object *result;
> +	u64 oem_platform_rev = 0;
> +
> +	// get OEM platform revision
> +	result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
> +					 MSHW0040_DSM_REVISION,
> +					 MSHW0040_DSM_GET_OMPR,
> +					 NULL, ACPI_TYPE_INTEGER);
> +
Does it mean, only 5th, 6th and newer platforms have OEM platform revision?
3rd/4th will get NULL result? Or the opposite?
> +	if (result) {
> +		oem_platform_rev = result->integer.value;
> +		ACPI_FREE(result);
> +	}
> +
> +	dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev);
> +
> +	return oem_platform_rev == 0 ? 0 : -ENODEV;
if 3rd/4th do not have this oem rev information while 5th/newer have,
why the latter returns NODEV(it actually has this info)?
> +}
> +
> +
>  static int surface_button_add(struct acpi_device *device)
>  {
>  	struct surface_button *button;
> @@ -154,6 +188,10 @@ static int surface_button_add(struct acpi_device *device)
>  	    strlen(SURFACE_BUTTON_OBJ_NAME)))
>  		return -ENODEV;
>  
> +	error = surface_button_check_MSHW0040(device);
> +	if (error)
> +		return error;
> +
ditto, 3rd/4th get error=0?
>  	button = kzalloc(sizeof(struct surface_button), GFP_KERNEL);
>  	if (!button)
>  		return -ENOMEM;
> -- 
> 2.22.0
> 
Best,
Yu
Maximilian Luz July 2, 2019, 1:25 a.m. UTC | #2
On 7/2/19 3:14 AM, Yu Chen wrote:
> On Tue, Jul 02, 2019 at 02:37:39AM +0200, Maximilian Luz wrote:
>> +/*
>> + * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device
>> + * ID (MSHW0040) for the power/volume buttons. Make sure this is the right
>> + * device by checking for the _DSM method and OEM Platform Revision.
>> + */
>> +static int surface_button_check_MSHW0040(struct acpi_device *dev)
>> +{
>> +	acpi_handle handle = dev->handle;
>> +	union acpi_object *result;
>> +	u64 oem_platform_rev = 0;
>> +
>> +	// get OEM platform revision
>> +	result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
>> +					 MSHW0040_DSM_REVISION,
>> +					 MSHW0040_DSM_GET_OMPR,
>> +					 NULL, ACPI_TYPE_INTEGER);
>> +
> Does it mean, only 5th, 6th and newer platforms have OEM platform revision?
> 3rd/4th will get NULL result? Or the opposite?

Correct, from my testing (with limited sample size) and AML code: 5th
and 6th generation devices have a non-zero OEM platform revision,
whereas 3rd and 4th gen. devices do not have any (i.e. result will be
NULL).

>> +	if (result) {
>> +		oem_platform_rev = result->integer.value;
>> +		ACPI_FREE(result);
>> +	}
>> +
>> +	dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev);
>> +
>> +	return oem_platform_rev == 0 ? 0 : -ENODEV;
> if 3rd/4th do not have this oem rev information while 5th/newer have,
> why the latter returns NODEV(it actually has this info)?

Since we always expect a non-zero platform revision (for 5th/6th gen.),
we can initialize it to zero and use that as "unknown"/"not available".
So if it can not be determined, we return NODEV.

>> +}

Cheers,
Maximilian
Maximilian Luz July 2, 2019, 1:33 a.m. UTC | #3
On 7/2/19 3:25 AM, Maximilian Luz wrote:
> On 7/2/19 3:14 AM, Yu Chen wrote:
>> On Tue, Jul 02, 2019 at 02:37:39AM +0200, Maximilian Luz wrote:
>>> +/*
>>> + * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device
>>> + * ID (MSHW0040) for the power/volume buttons. Make sure this is the right
>>> + * device by checking for the _DSM method and OEM Platform Revision.
>>> + */
>>> +static int surface_button_check_MSHW0040(struct acpi_device *dev)
>>> +{
>>> +    acpi_handle handle = dev->handle;
>>> +    union acpi_object *result;
>>> +    u64 oem_platform_rev = 0;
>>> +
>>> +    // get OEM platform revision
>>> +    result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
>>> +                     MSHW0040_DSM_REVISION,
>>> +                     MSHW0040_DSM_GET_OMPR,
>>> +                     NULL, ACPI_TYPE_INTEGER);
>>> +
>> Does it mean, only 5th, 6th and newer platforms have OEM platform revision?
>> 3rd/4th will get NULL result? Or the opposite?
> 
> Correct, from my testing (with limited sample size) and AML code: 5th
> and 6th generation devices have a non-zero OEM platform revision,
> whereas 3rd and 4th gen. devices do not have any (i.e. result will be
> NULL).
> 
>>> +    if (result) {
>>> +        oem_platform_rev = result->integer.value;
>>> +        ACPI_FREE(result);
>>> +    }
>>> +
>>> +    dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev);
>>> +
>>> +    return oem_platform_rev == 0 ? 0 : -ENODEV;
>> if 3rd/4th do not have this oem rev information while 5th/newer have,
>> why the latter returns NODEV(it actually has this info)?
> 
> Since we always expect a non-zero platform revision (for 5th/6th gen.),
> we can initialize it to zero and use that as "unknown"/"not available".
> So if it can not be determined, we return NODEV.

Sorry, small mistake here: If it can be determined (i.e. is 5th or 6th
gen.) then we return NODEV. Not the other way around.

Also to clarify on your last question:

On 7/2/19 3:14 AM, Yu Chen wrote:
>>   static int surface_button_add(struct acpi_device *device)
>>   {
>>   	struct surface_button *button;
>> @@ -154,6 +188,10 @@ static int surface_button_add(struct acpi_device *device)
>>   	    strlen(SURFACE_BUTTON_OBJ_NAME)))
>>   		return -ENODEV;
>>   
>> +	error = surface_button_check_MSHW0040(device);
>> +	if (error)
>> +		return error;
>> +
> ditto, 3rd/4th get error=0?

You are correct.

Maximilian
Chen Yu July 2, 2019, 1:57 a.m. UTC | #4
On Tue, Jul 02, 2019 at 03:33:20AM +0200, Maximilian Luz wrote:
> On 7/2/19 3:25 AM, Maximilian Luz wrote:
> > On 7/2/19 3:14 AM, Yu Chen wrote:
> > > On Tue, Jul 02, 2019 at 02:37:39AM +0200, Maximilian Luz wrote:
> > > > +/*
> > > > + * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device
> > > > + * ID (MSHW0040) for the power/volume buttons. Make sure this is the right
> > > > + * device by checking for the _DSM method and OEM Platform Revision.
> > > > + */
> > > > +static int surface_button_check_MSHW0040(struct acpi_device *dev)
> > > > +{
> > > > +    acpi_handle handle = dev->handle;
> > > > +    union acpi_object *result;
> > > > +    u64 oem_platform_rev = 0;
> > > > +
> > > > +    // get OEM platform revision
> > > > +    result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
> > > > +                     MSHW0040_DSM_REVISION,
> > > > +                     MSHW0040_DSM_GET_OMPR,
> > > > +                     NULL, ACPI_TYPE_INTEGER);
> > > > +
> > > Does it mean, only 5th, 6th and newer platforms have OEM platform revision?
> > > 3rd/4th will get NULL result? Or the opposite?
> > 
> > Correct, from my testing (with limited sample size) and AML code: 5th
> > and 6th generation devices have a non-zero OEM platform revision,
> > whereas 3rd and 4th gen. devices do not have any (i.e. result will be
> > NULL).
> > 
> > > > +    if (result) {
> > > > +        oem_platform_rev = result->integer.value;
> > > > +        ACPI_FREE(result);
> > > > +    }
> > > > +
> > > > +    dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev);
> > > > +
> > > > +    return oem_platform_rev == 0 ? 0 : -ENODEV;
> > > if 3rd/4th do not have this oem rev information while 5th/newer have,
> > > why the latter returns NODEV(it actually has this info)?
> > 
> > Since we always expect a non-zero platform revision (for 5th/6th gen.),
> > we can initialize it to zero and use that as "unknown"/"not available".
> > So if it can not be determined, we return NODEV.
> 
> Sorry, small mistake here: If it can be determined (i.e. is 5th or 6th
> gen.) then we return NODEV. Not the other way around.
>
How about using a boolean, according to the function name, if a mshw0040 revison
is detected then returns true other wise false. Other than that,
Acked-by: Chen Yu <yu.c.chen@intel.com>

Best,
Chenyu
> Also to clarify on your last question:
> 
> On 7/2/19 3:14 AM, Yu Chen wrote:
> > >   static int surface_button_add(struct acpi_device *device)
> > >   {
> > >   	struct surface_button *button;
> > > @@ -154,6 +188,10 @@ static int surface_button_add(struct acpi_device *device)
> > >   	    strlen(SURFACE_BUTTON_OBJ_NAME)))
> > >   		return -ENODEV;
> > > +	error = surface_button_check_MSHW0040(device);
> > > +	if (error)
> > > +		return error;
> > > +
> > ditto, 3rd/4th get error=0?
> 
> You are correct.
> 
> Maximilian
Maximilian Luz July 2, 2019, 2:04 a.m. UTC | #5
On 7/2/19 3:57 AM, Yu Chen wrote:
> How about using a boolean, according to the function name, if a mshw0040 revison
> is detected then returns true other wise false. Other than that,
> Acked-by: Chen Yu <yu.c.chen@intel.com>

I can change that if you want me to. Just thought this might be a bit
more flexible in case we ever have to adapt the check for future device
generations.

Thanks,
Maximilian
Andy Shevchenko July 18, 2019, 5:43 p.m. UTC | #6
On Tue, Jul 2, 2019 at 3:38 AM Maximilian Luz <luzmaximilian@gmail.com> wrote:
>
> Do not use the surfacepro3_button driver on newer Microsoft Surface
> models, only use it on the Surface Pro 3 and 4. Newer models (5th, 6th
> and possibly future generations) use the same device as the Surface Pro
> 4 to represent their volume and power buttons (MSHW0040), but their
> acutal implementation is significantly different. This patch ensures
> that the surfacepro3_button driver is only used on the Pro 3 and 4
> models, allowing a different driver to bind on other models.
>

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>

Assuming it will go thru Input subsystem.

> Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
> ---
>  drivers/platform/x86/surfacepro3_button.c | 38 +++++++++++++++++++++++
>  1 file changed, 38 insertions(+)
>
> diff --git a/drivers/platform/x86/surfacepro3_button.c b/drivers/platform/x86/surfacepro3_button.c
> index 47c6d000465a..0e2c7dfafd9f 100644
> --- a/drivers/platform/x86/surfacepro3_button.c
> +++ b/drivers/platform/x86/surfacepro3_button.c
> @@ -20,6 +20,12 @@
>  #define SURFACE_BUTTON_OBJ_NAME                "VGBI"
>  #define SURFACE_BUTTON_DEVICE_NAME     "Surface Pro 3/4 Buttons"
>
> +#define MSHW0040_DSM_REVISION          0x01
> +#define MSHW0040_DSM_GET_OMPR          0x02    // get OEM Platform Revision
> +static const guid_t MSHW0040_DSM_UUID =
> +       GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
> +                 0x49, 0x80, 0x35);
> +
>  #define SURFACE_BUTTON_NOTIFY_TABLET_MODE      0xc8
>
>  #define SURFACE_BUTTON_NOTIFY_PRESS_POWER      0xc6
> @@ -142,6 +148,34 @@ static int surface_button_resume(struct device *dev)
>  }
>  #endif
>
> +/*
> + * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device
> + * ID (MSHW0040) for the power/volume buttons. Make sure this is the right
> + * device by checking for the _DSM method and OEM Platform Revision.
> + */
> +static int surface_button_check_MSHW0040(struct acpi_device *dev)
> +{
> +       acpi_handle handle = dev->handle;
> +       union acpi_object *result;
> +       u64 oem_platform_rev = 0;
> +
> +       // get OEM platform revision
> +       result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
> +                                        MSHW0040_DSM_REVISION,
> +                                        MSHW0040_DSM_GET_OMPR,
> +                                        NULL, ACPI_TYPE_INTEGER);
> +
> +       if (result) {
> +               oem_platform_rev = result->integer.value;
> +               ACPI_FREE(result);
> +       }
> +
> +       dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev);
> +
> +       return oem_platform_rev == 0 ? 0 : -ENODEV;
> +}
> +
> +
>  static int surface_button_add(struct acpi_device *device)
>  {
>         struct surface_button *button;
> @@ -154,6 +188,10 @@ static int surface_button_add(struct acpi_device *device)
>             strlen(SURFACE_BUTTON_OBJ_NAME)))
>                 return -ENODEV;
>
> +       error = surface_button_check_MSHW0040(device);
> +       if (error)
> +               return error;
> +
>         button = kzalloc(sizeof(struct surface_button), GFP_KERNEL);
>         if (!button)
>                 return -ENOMEM;
> --
> 2.22.0
>

Patch
diff mbox series

diff --git a/drivers/platform/x86/surfacepro3_button.c b/drivers/platform/x86/surfacepro3_button.c
index 47c6d000465a..0e2c7dfafd9f 100644
--- a/drivers/platform/x86/surfacepro3_button.c
+++ b/drivers/platform/x86/surfacepro3_button.c
@@ -20,6 +20,12 @@ 
 #define SURFACE_BUTTON_OBJ_NAME		"VGBI"
 #define SURFACE_BUTTON_DEVICE_NAME	"Surface Pro 3/4 Buttons"
 
+#define MSHW0040_DSM_REVISION		0x01
+#define MSHW0040_DSM_GET_OMPR		0x02	// get OEM Platform Revision
+static const guid_t MSHW0040_DSM_UUID =
+	GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
+		  0x49, 0x80, 0x35);
+
 #define SURFACE_BUTTON_NOTIFY_TABLET_MODE	0xc8
 
 #define SURFACE_BUTTON_NOTIFY_PRESS_POWER	0xc6
@@ -142,6 +148,34 @@  static int surface_button_resume(struct device *dev)
 }
 #endif
 
+/*
+ * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device
+ * ID (MSHW0040) for the power/volume buttons. Make sure this is the right
+ * device by checking for the _DSM method and OEM Platform Revision.
+ */
+static int surface_button_check_MSHW0040(struct acpi_device *dev)
+{
+	acpi_handle handle = dev->handle;
+	union acpi_object *result;
+	u64 oem_platform_rev = 0;
+
+	// get OEM platform revision
+	result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
+					 MSHW0040_DSM_REVISION,
+					 MSHW0040_DSM_GET_OMPR,
+					 NULL, ACPI_TYPE_INTEGER);
+
+	if (result) {
+		oem_platform_rev = result->integer.value;
+		ACPI_FREE(result);
+	}
+
+	dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev);
+
+	return oem_platform_rev == 0 ? 0 : -ENODEV;
+}
+
+
 static int surface_button_add(struct acpi_device *device)
 {
 	struct surface_button *button;
@@ -154,6 +188,10 @@  static int surface_button_add(struct acpi_device *device)
 	    strlen(SURFACE_BUTTON_OBJ_NAME)))
 		return -ENODEV;
 
+	error = surface_button_check_MSHW0040(device);
+	if (error)
+		return error;
+
 	button = kzalloc(sizeof(struct surface_button), GFP_KERNEL);
 	if (!button)
 		return -ENOMEM;