diff mbox series

[2/8] HID: usbhid: Make hid_is_usb() non-inline

Message ID 20221222-hid-v1-2-f4a6c35487a5@weissschuh.net
State New
Headers show
Series HID: remove some unneeded exported symbols from hid.h | expand

Commit Message

Thomas Weißschuh Dec. 22, 2022, 5:10 a.m. UTC 
By making hid_is_usb() a non-inline function the lowlevel usbhid driver
does not have to be exported anymore.

Also mark the argument as const as it is not modified.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 drivers/hid/usbhid/hid-core.c | 6 ++++++
 include/linux/hid.h           | 5 +----
 2 files changed, 7 insertions(+), 4 deletions(-)

Comments

Benjamin Tissoires Dec. 22, 2022, 9:12 p.m. UTC | #1 
On Thu, Dec 22, 2022 at 6:16 AM Thomas Weißschuh <linux@weissschuh.net> wrote:
>
> By making hid_is_usb() a non-inline function the lowlevel usbhid driver
> does not have to be exported anymore.
>
> Also mark the argument as const as it is not modified.
>
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> ---
>  drivers/hid/usbhid/hid-core.c | 6 ++++++
>  include/linux/hid.h           | 5 +----
>  2 files changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
> index be4c731aaa65..54b0280d0073 100644
> --- a/drivers/hid/usbhid/hid-core.c
> +++ b/drivers/hid/usbhid/hid-core.c
> @@ -1334,6 +1334,12 @@ struct hid_ll_driver usb_hid_driver = {
>  };
>  EXPORT_SYMBOL_GPL(usb_hid_driver);
>
> +bool hid_is_usb(const struct hid_device *hdev)
> +{
> +       return hdev->ll_driver == &usb_hid_driver;
> +}
> +EXPORT_SYMBOL_GPL(hid_is_usb);
> +
>  static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
>  {
>         struct usb_host_interface *interface = intf->cur_altsetting;
> diff --git a/include/linux/hid.h b/include/linux/hid.h
> index 8677ae38599e..e8400aa78522 100644
> --- a/include/linux/hid.h
> +++ b/include/linux/hid.h
> @@ -864,10 +864,7 @@ static inline bool hid_is_using_ll_driver(struct hid_device *hdev,
>         return hdev->ll_driver == driver;
>  }
>
> -static inline bool hid_is_usb(struct hid_device *hdev)
> -{
> -       return hid_is_using_ll_driver(hdev, &usb_hid_driver);
> -}
> +extern bool hid_is_usb(const struct hid_device *hdev);

The problem here is that CONFIG_USB_HID can be set to either m or n.
In the n case, you'll end up with an undefined symbol, in the m case,
it won't link too if CONFIG_HID is set to Y (and it'll be quite a mess
to call it if the module is not loaded yet).

Cheers,
Benjamin


>
>
>  #define        PM_HINT_FULLON  1<<5
>  #define PM_HINT_NORMAL 1<<1
>
> --
> 2.39.0
>
Thomas Weißschuh Dec. 22, 2022, 9:37 p.m. UTC | #2 
Dec 22, 2022 16:13:06 Benjamin Tissoires <benjamin.tissoires@redhat.com>:

> On Thu, Dec 22, 2022 at 6:16 AM Thomas Weißschuh <linux@weissschuh.net> wrote:
>>
>> By making hid_is_usb() a non-inline function the lowlevel usbhid driver
>> does not have to be exported anymore.
>>
>> Also mark the argument as const as it is not modified.
>>
>> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
>> ---
>> drivers/hid/usbhid/hid-core.c | 6 ++++++
>> include/linux/hid.h           | 5 +----
>> 2 files changed, 7 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
>> index be4c731aaa65..54b0280d0073 100644
>> --- a/drivers/hid/usbhid/hid-core.c
>> +++ b/drivers/hid/usbhid/hid-core.c
>> @@ -1334,6 +1334,12 @@ struct hid_ll_driver usb_hid_driver = {
>> };
>> EXPORT_SYMBOL_GPL(usb_hid_driver);
>>
>> +bool hid_is_usb(const struct hid_device *hdev)
>> +{
>> +       return hdev->ll_driver == &usb_hid_driver;
>> +}
>> +EXPORT_SYMBOL_GPL(hid_is_usb);
>> +
>> static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
>> {
>>         struct usb_host_interface *interface = intf->cur_altsetting;
>> diff --git a/include/linux/hid.h b/include/linux/hid.h
>> index 8677ae38599e..e8400aa78522 100644
>> --- a/include/linux/hid.h
>> +++ b/include/linux/hid.h
>> @@ -864,10 +864,7 @@ static inline bool hid_is_using_ll_driver(struct hid_device *hdev,
>>         return hdev->ll_driver == driver;
>> }
>>
>> -static inline bool hid_is_usb(struct hid_device *hdev)
>> -{
>> -       return hid_is_using_ll_driver(hdev, &usb_hid_driver);
>> -}
>> +extern bool hid_is_usb(const struct hid_device *hdev);
>
> The problem here is that CONFIG_USB_HID can be set to either m or n.
> In the n case, you'll end up with an undefined symbol, in the m case,
> it won't link too if CONFIG_HID is set to Y (and it'll be quite a mess
> to call it if the module is not loaded yet).

Shouldn't we already have the same problem with
the symbol usb_hid_driver itself that is defined
right next to the new hid_is_usb()?

Thomas

>>
>> #define        PM_HINT_FULLON  1<<5
>> #define PM_HINT_NORMAL 1<<1
>>
>> --
>> 2.39.0
>>
Benjamin Tissoires Dec. 23, 2022, 7:56 a.m. UTC | #3 
On Thu, Dec 22, 2022 at 10:46 PM Thomas Weißschuh <thomas@t-8ch.de> wrote:
>
>
> Dec 22, 2022 16:13:06 Benjamin Tissoires <benjamin.tissoires@redhat.com>:
>
> > On Thu, Dec 22, 2022 at 6:16 AM Thomas Weißschuh <linux@weissschuh.net> wrote:
> >>
> >> By making hid_is_usb() a non-inline function the lowlevel usbhid driver
> >> does not have to be exported anymore.
> >>
> >> Also mark the argument as const as it is not modified.
> >>
> >> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> >> ---
> >> drivers/hid/usbhid/hid-core.c | 6 ++++++
> >> include/linux/hid.h           | 5 +----
> >> 2 files changed, 7 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
> >> index be4c731aaa65..54b0280d0073 100644
> >> --- a/drivers/hid/usbhid/hid-core.c
> >> +++ b/drivers/hid/usbhid/hid-core.c
> >> @@ -1334,6 +1334,12 @@ struct hid_ll_driver usb_hid_driver = {
> >> };
> >> EXPORT_SYMBOL_GPL(usb_hid_driver);
> >>
> >> +bool hid_is_usb(const struct hid_device *hdev)
> >> +{
> >> +       return hdev->ll_driver == &usb_hid_driver;
> >> +}
> >> +EXPORT_SYMBOL_GPL(hid_is_usb);
> >> +
> >> static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
> >> {
> >>         struct usb_host_interface *interface = intf->cur_altsetting;
> >> diff --git a/include/linux/hid.h b/include/linux/hid.h
> >> index 8677ae38599e..e8400aa78522 100644
> >> --- a/include/linux/hid.h
> >> +++ b/include/linux/hid.h
> >> @@ -864,10 +864,7 @@ static inline bool hid_is_using_ll_driver(struct hid_device *hdev,
> >>         return hdev->ll_driver == driver;
> >> }
> >>
> >> -static inline bool hid_is_usb(struct hid_device *hdev)
> >> -{
> >> -       return hid_is_using_ll_driver(hdev, &usb_hid_driver);
> >> -}
> >> +extern bool hid_is_usb(const struct hid_device *hdev);
> >
> > The problem here is that CONFIG_USB_HID can be set to either m or n.
> > In the n case, you'll end up with an undefined symbol, in the m case,
> > it won't link too if CONFIG_HID is set to Y (and it'll be quite a mess
> > to call it if the module is not loaded yet).
>
> Shouldn't we already have the same problem with
> the symbol usb_hid_driver itself that is defined
> right next to the new hid_is_usb()?

Yeah, sorry, my bad. All of the callers of this function are modules
which depend on CONFIG_USB_HID in the Kconfig, so we should be good.
Sorry for the noise.

I shouldn't do reviews at 10pm :(

Cheers,
Benjamin

>
> Thomas
>
> >>
> >> #define        PM_HINT_FULLON  1<<5
> >> #define PM_HINT_NORMAL 1<<1
> >>
> >> --
> >> 2.39.0
> >>
>
diff mbox series

Patch

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index be4c731aaa65..54b0280d0073 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -1334,6 +1334,12 @@  struct hid_ll_driver usb_hid_driver = {
 };
 EXPORT_SYMBOL_GPL(usb_hid_driver);
 
+bool hid_is_usb(const struct hid_device *hdev)
+{
+	return hdev->ll_driver == &usb_hid_driver;
+}
+EXPORT_SYMBOL_GPL(hid_is_usb);
+
 static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {
 	struct usb_host_interface *interface = intf->cur_altsetting;
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 8677ae38599e..e8400aa78522 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -864,10 +864,7 @@  static inline bool hid_is_using_ll_driver(struct hid_device *hdev,
 	return hdev->ll_driver == driver;
 }
 
-static inline bool hid_is_usb(struct hid_device *hdev)
-{
-	return hid_is_using_ll_driver(hdev, &usb_hid_driver);
-}
+extern bool hid_is_usb(const struct hid_device *hdev);
 
 #define	PM_HINT_FULLON	1<<5
 #define PM_HINT_NORMAL	1<<1