| Message ID | 20230426212848.108562-2-W_Armin@gmx.de (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | platform/x86: Allow retrieving the number of WMI object instances | expand |
On Wed, Apr 26, 2023 at 11:28:47PM +0200, Armin Wolf wrote: > Currently, the WMI driver core knows how many instances of a given > WMI object exist, but WMI drivers cannot access this information. > At the same time, some current and upcoming WMI drivers want to > have access to this information. Add wmi_instance_count() and > wmidev_instance_count() to allow WMI drivers to get the number of > WMI object instances. > > Signed-off-by: Armin Wolf <W_Armin@gmx.de> Tested-by: James Seo <james@equiv.tech>
Hi Armin, Thank you for your work on this. On 4/26/23 23:28, Armin Wolf wrote: > Currently, the WMI driver core knows how many instances of a given > WMI object exist, but WMI drivers cannot access this information. > At the same time, some current and upcoming WMI drivers want to > have access to this information. Add wmi_instance_count() and > wmidev_instance_count() to allow WMI drivers to get the number of > WMI object instances. > > Signed-off-by: Armin Wolf <W_Armin@gmx.de> > --- > drivers/platform/x86/wmi.c | 40 ++++++++++++++++++++++++++++++++++++++ > include/linux/acpi.h | 2 ++ > include/linux/wmi.h | 2 ++ > 3 files changed, 44 insertions(+) > > diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c > index c226dd4163a1..7c1a904dec5f 100644 > --- a/drivers/platform/x86/wmi.c > +++ b/drivers/platform/x86/wmi.c > @@ -263,6 +263,46 @@ int set_required_buffer_size(struct wmi_device *wdev, u64 length) > } > EXPORT_SYMBOL_GPL(set_required_buffer_size); > > +/** > + * wmi_instance_count - Get number of WMI object instances > + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba > + * @instance_count: variable to hold the instance count > + * > + * Get the number of WMI object instances. > + * > + * Returns: acpi_status signaling success or error. > + */ > +acpi_status wmi_instance_count(const char *guid_string, u8 *instance_count) > +{ > + struct wmi_block *wblock; > + acpi_status status; > + > + status = find_guid(guid_string, &wblock); > + if (ACPI_FAILURE(status)) > + return status; > + > + *instance_count = wmidev_instance_count(&wblock->dev); > + > + return AE_OK; > +} > +EXPORT_SYMBOL_GPL(wmi_instance_count); I would prefer this to have a normal kernel function prototype which returns -errno rather then returning an acpi_status. E.g. : /** * wmi_instance_count - Get number of WMI object instances * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba * * Get the number of WMI object instances. * * Returns: The number of WMI object instances, 0 if the GUID is not found. */ int wmi_instance_count(const char *guid_string) { struct wmi_block *wblock; acpi_status status; status = find_guid(guid_string, &wblock); if (ACPI_FAILURE(status)) return 0; return wmidev_instance_count(&wblock->dev); } EXPORT_SYMBOL_GPL(wmi_instance_count); This will also allow this to completely replace the get_instance_count() function in dell-wmi-sysman. Note I have just gone with always returning 0 here on error. I guess you could look at the status and return 0 for not-found and -errno for other errors but I don't think any callers will care for the difference, so just always returning 0 seems easier for callers to deal with. As always this is just a suggestion, let me know if you think this is a bad idea. Regards, Hans > + > +/** > + * wmidev_instance_count - Get number of WMI object instances > + * @wdev: A wmi bus device from a driver > + * > + * Get the number of WMI object instances. > + * > + * Returns: Number of WMI object instances. > + */ > +u8 wmidev_instance_count(struct wmi_device *wdev) > +{ > + struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev); > + > + return wblock->gblock.instance_count; > +} > +EXPORT_SYMBOL_GPL(wmidev_instance_count); > + > /** > * wmi_evaluate_method - Evaluate a WMI method (deprecated) > * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index efff750f326d..ab2a4b23e7a3 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -412,6 +412,8 @@ extern bool acpi_is_pnp_device(struct acpi_device *); > > typedef void (*wmi_notify_handler) (u32 value, void *context); > > +acpi_status wmi_instance_count(const char *guid, u8 *instance_count); > + > extern acpi_status wmi_evaluate_method(const char *guid, u8 instance, > u32 method_id, > const struct acpi_buffer *in, > diff --git a/include/linux/wmi.h b/include/linux/wmi.h > index c1a3bd4e4838..763bd382cf2d 100644 > --- a/include/linux/wmi.h > +++ b/include/linux/wmi.h > @@ -35,6 +35,8 @@ extern acpi_status wmidev_evaluate_method(struct wmi_device *wdev, > extern union acpi_object *wmidev_block_query(struct wmi_device *wdev, > u8 instance); > > +u8 wmidev_instance_count(struct wmi_device *wdev); > + > extern int set_required_buffer_size(struct wmi_device *wdev, u64 length); > > /** > -- > 2.30.2 >
Am 27.04.23 um 11:43 schrieb Hans de Goede: > Hi Armin, > > Thank you for your work on this. > > On 4/26/23 23:28, Armin Wolf wrote: >> Currently, the WMI driver core knows how many instances of a given >> WMI object exist, but WMI drivers cannot access this information. >> At the same time, some current and upcoming WMI drivers want to >> have access to this information. Add wmi_instance_count() and >> wmidev_instance_count() to allow WMI drivers to get the number of >> WMI object instances. >> >> Signed-off-by: Armin Wolf <W_Armin@gmx.de> >> --- >> drivers/platform/x86/wmi.c | 40 ++++++++++++++++++++++++++++++++++++++ >> include/linux/acpi.h | 2 ++ >> include/linux/wmi.h | 2 ++ >> 3 files changed, 44 insertions(+) >> >> diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c >> index c226dd4163a1..7c1a904dec5f 100644 >> --- a/drivers/platform/x86/wmi.c >> +++ b/drivers/platform/x86/wmi.c >> @@ -263,6 +263,46 @@ int set_required_buffer_size(struct wmi_device *wdev, u64 length) >> } >> EXPORT_SYMBOL_GPL(set_required_buffer_size); >> >> +/** >> + * wmi_instance_count - Get number of WMI object instances >> + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba >> + * @instance_count: variable to hold the instance count >> + * >> + * Get the number of WMI object instances. >> + * >> + * Returns: acpi_status signaling success or error. >> + */ >> +acpi_status wmi_instance_count(const char *guid_string, u8 *instance_count) >> +{ >> + struct wmi_block *wblock; >> + acpi_status status; >> + >> + status = find_guid(guid_string, &wblock); >> + if (ACPI_FAILURE(status)) >> + return status; >> + >> + *instance_count = wmidev_instance_count(&wblock->dev); >> + >> + return AE_OK; >> +} >> +EXPORT_SYMBOL_GPL(wmi_instance_count); > I would prefer this to have a normal kernel function prototype > which returns -errno rather then returning an acpi_status. E.g. : > > /** > * wmi_instance_count - Get number of WMI object instances > * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba > * > * Get the number of WMI object instances. > * > * Returns: The number of WMI object instances, 0 if the GUID is not found. > */ > int wmi_instance_count(const char *guid_string) > { > struct wmi_block *wblock; > acpi_status status; > > status = find_guid(guid_string, &wblock); > if (ACPI_FAILURE(status)) > return 0; > > return wmidev_instance_count(&wblock->dev); > } > EXPORT_SYMBOL_GPL(wmi_instance_count); > > This will also allow this to completely replace > the get_instance_count() function in dell-wmi-sysman. > > Note I have just gone with always returning 0 here > on error. I guess you could look at the status and > return 0 for not-found and -errno for other errors > but I don't think any callers will care for the difference, > so just always returning 0 seems easier for callers to > deal with. > > As always this is just a suggestion, let me know if > you think this is a bad idea. > > Regards, > > Hans > I like this idea. Returning a negative errno on error would allow drivers to distinguish between "WMI object not found" and "zero instances found", which might be useful for some drivers. Maybe a function for converting ACPI errors to POSIX errors already exists, otherwise i will just write one myself. Armin Wolf > >> + >> +/** >> + * wmidev_instance_count - Get number of WMI object instances >> + * @wdev: A wmi bus device from a driver >> + * >> + * Get the number of WMI object instances. >> + * >> + * Returns: Number of WMI object instances. >> + */ >> +u8 wmidev_instance_count(struct wmi_device *wdev) >> +{ >> + struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev); >> + >> + return wblock->gblock.instance_count; >> +} >> +EXPORT_SYMBOL_GPL(wmidev_instance_count); >> + >> /** >> * wmi_evaluate_method - Evaluate a WMI method (deprecated) >> * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba >> diff --git a/include/linux/acpi.h b/include/linux/acpi.h >> index efff750f326d..ab2a4b23e7a3 100644 >> --- a/include/linux/acpi.h >> +++ b/include/linux/acpi.h >> @@ -412,6 +412,8 @@ extern bool acpi_is_pnp_device(struct acpi_device *); >> >> typedef void (*wmi_notify_handler) (u32 value, void *context); >> >> +acpi_status wmi_instance_count(const char *guid, u8 *instance_count); >> + >> extern acpi_status wmi_evaluate_method(const char *guid, u8 instance, >> u32 method_id, >> const struct acpi_buffer *in, >> diff --git a/include/linux/wmi.h b/include/linux/wmi.h >> index c1a3bd4e4838..763bd382cf2d 100644 >> --- a/include/linux/wmi.h >> +++ b/include/linux/wmi.h >> @@ -35,6 +35,8 @@ extern acpi_status wmidev_evaluate_method(struct wmi_device *wdev, >> extern union acpi_object *wmidev_block_query(struct wmi_device *wdev, >> u8 instance); >> >> +u8 wmidev_instance_count(struct wmi_device *wdev); >> + >> extern int set_required_buffer_size(struct wmi_device *wdev, u64 length); >> >> /** >> -- >> 2.30.2 >>
Hi, On 4/27/23 18:26, Armin Wolf wrote: > Am 27.04.23 um 11:43 schrieb Hans de Goede: > >> Hi Armin, >> >> Thank you for your work on this. >> >> On 4/26/23 23:28, Armin Wolf wrote: >>> Currently, the WMI driver core knows how many instances of a given >>> WMI object exist, but WMI drivers cannot access this information. >>> At the same time, some current and upcoming WMI drivers want to >>> have access to this information. Add wmi_instance_count() and >>> wmidev_instance_count() to allow WMI drivers to get the number of >>> WMI object instances. >>> >>> Signed-off-by: Armin Wolf <W_Armin@gmx.de> >>> --- >>> drivers/platform/x86/wmi.c | 40 ++++++++++++++++++++++++++++++++++++++ >>> include/linux/acpi.h | 2 ++ >>> include/linux/wmi.h | 2 ++ >>> 3 files changed, 44 insertions(+) >>> >>> diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c >>> index c226dd4163a1..7c1a904dec5f 100644 >>> --- a/drivers/platform/x86/wmi.c >>> +++ b/drivers/platform/x86/wmi.c >>> @@ -263,6 +263,46 @@ int set_required_buffer_size(struct wmi_device *wdev, u64 length) >>> } >>> EXPORT_SYMBOL_GPL(set_required_buffer_size); >>> >>> +/** >>> + * wmi_instance_count - Get number of WMI object instances >>> + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba >>> + * @instance_count: variable to hold the instance count >>> + * >>> + * Get the number of WMI object instances. >>> + * >>> + * Returns: acpi_status signaling success or error. >>> + */ >>> +acpi_status wmi_instance_count(const char *guid_string, u8 *instance_count) >>> +{ >>> + struct wmi_block *wblock; >>> + acpi_status status; >>> + >>> + status = find_guid(guid_string, &wblock); >>> + if (ACPI_FAILURE(status)) >>> + return status; >>> + >>> + *instance_count = wmidev_instance_count(&wblock->dev); >>> + >>> + return AE_OK; >>> +} >>> +EXPORT_SYMBOL_GPL(wmi_instance_count); >> I would prefer this to have a normal kernel function prototype >> which returns -errno rather then returning an acpi_status. E.g. : >> >> /** >> * wmi_instance_count - Get number of WMI object instances >> * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba >> * >> * Get the number of WMI object instances. >> * >> * Returns: The number of WMI object instances, 0 if the GUID is not found. >> */ >> int wmi_instance_count(const char *guid_string) >> { >> struct wmi_block *wblock; >> acpi_status status; >> >> status = find_guid(guid_string, &wblock); >> if (ACPI_FAILURE(status)) >> return 0; >> >> return wmidev_instance_count(&wblock->dev); >> } >> EXPORT_SYMBOL_GPL(wmi_instance_count); >> >> This will also allow this to completely replace >> the get_instance_count() function in dell-wmi-sysman. >> >> Note I have just gone with always returning 0 here >> on error. I guess you could look at the status and >> return 0 for not-found and -errno for other errors >> but I don't think any callers will care for the difference, >> so just always returning 0 seems easier for callers to >> deal with. >> >> As always this is just a suggestion, let me know if >> you think this is a bad idea. >> >> Regards, >> >> Hans >> > I like this idea. Returning a negative errno on error would allow drivers to > distinguish between "WMI object not found" and "zero instances found", which > might be useful for some drivers. > > Maybe a function for converting ACPI errors to POSIX errors already exists, > otherwise i will just write one myself. Ok, that sounds good to me. I'm looking forward to a non RFC submission of these changes. Regards, Hans
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index c226dd4163a1..7c1a904dec5f 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -263,6 +263,46 @@ int set_required_buffer_size(struct wmi_device *wdev, u64 length) } EXPORT_SYMBOL_GPL(set_required_buffer_size); +/** + * wmi_instance_count - Get number of WMI object instances + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba + * @instance_count: variable to hold the instance count + * + * Get the number of WMI object instances. + * + * Returns: acpi_status signaling success or error. + */ +acpi_status wmi_instance_count(const char *guid_string, u8 *instance_count) +{ + struct wmi_block *wblock; + acpi_status status; + + status = find_guid(guid_string, &wblock); + if (ACPI_FAILURE(status)) + return status; + + *instance_count = wmidev_instance_count(&wblock->dev); + + return AE_OK; +} +EXPORT_SYMBOL_GPL(wmi_instance_count); + +/** + * wmidev_instance_count - Get number of WMI object instances + * @wdev: A wmi bus device from a driver + * + * Get the number of WMI object instances. + * + * Returns: Number of WMI object instances. + */ +u8 wmidev_instance_count(struct wmi_device *wdev) +{ + struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev); + + return wblock->gblock.instance_count; +} +EXPORT_SYMBOL_GPL(wmidev_instance_count); + /** * wmi_evaluate_method - Evaluate a WMI method (deprecated) * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba diff --git a/include/linux/acpi.h b/include/linux/acpi.h index efff750f326d..ab2a4b23e7a3 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -412,6 +412,8 @@ extern bool acpi_is_pnp_device(struct acpi_device *); typedef void (*wmi_notify_handler) (u32 value, void *context); +acpi_status wmi_instance_count(const char *guid, u8 *instance_count); + extern acpi_status wmi_evaluate_method(const char *guid, u8 instance, u32 method_id, const struct acpi_buffer *in, diff --git a/include/linux/wmi.h b/include/linux/wmi.h index c1a3bd4e4838..763bd382cf2d 100644 --- a/include/linux/wmi.h +++ b/include/linux/wmi.h @@ -35,6 +35,8 @@ extern acpi_status wmidev_evaluate_method(struct wmi_device *wdev, extern union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance); +u8 wmidev_instance_count(struct wmi_device *wdev); + extern int set_required_buffer_size(struct wmi_device *wdev, u64 length); /**
Currently, the WMI driver core knows how many instances of a given WMI object exist, but WMI drivers cannot access this information. At the same time, some current and upcoming WMI drivers want to have access to this information. Add wmi_instance_count() and wmidev_instance_count() to allow WMI drivers to get the number of WMI object instances. Signed-off-by: Armin Wolf <W_Armin@gmx.de> --- drivers/platform/x86/wmi.c | 40 ++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 2 ++ include/linux/wmi.h | 2 ++ 3 files changed, 44 insertions(+) -- 2.30.2