Re: [PATCH 3/3] crypto: inside-secure - Remove #ifdef checks

[Bjorn Helgaas]

On Mon, Sep 30, 2019 at 02:14:35PM +0200, Arnd Bergmann wrote:
> When both PCI and OF are disabled, no drivers are registered, and
> we get some unused-function warnings:
> 
> drivers/crypto/inside-secure/safexcel.c:1221:13: error: unused function 'safexcel_unregister_algorithms' [-Werror,-Wunused-function]
> static void safexcel_unregister_algorithms(struct safexcel_crypto_priv *priv)
> drivers/crypto/inside-secure/safexcel.c:1307:12: error: unused function 'safexcel_probe_generic' [-Werror,-Wunused-function]
> static int safexcel_probe_generic(void *pdev,
> drivers/crypto/inside-secure/safexcel.c:1531:13: error: unused function 'safexcel_hw_reset_rings' [-Werror,-Wunused-function]
> static void safexcel_hw_reset_rings(struct safexcel_crypto_priv *priv)
> 
> It's better to make the compiler see what is going on and remove
> such ifdef checks completely. In case of PCI, this is trivial since
> pci_register_driver() is defined to an empty function that makes the
> compiler subsequently drop all unused code silently.
> 
> The global pcireg_rc/ofreg_rc variables are not actually needed here
> since the driver registration does not fail in ways that would make
> it helpful.
> 
> For CONFIG_OF, an IS_ENABLED() check is still required, since platform
> drivers can exist both with and without it.
> 
> A little change to linux/pci.h is needed to ensure that
> pcim_enable_device() is visible to the driver. Moving the declaration
> outside of ifdef would be sufficient here, but for consistency with the
> rest of the file, adding an inline helper is probably best.
> 
> Fixes: 212ef6f29e5b ("crypto: inside-secure - Fix unused variable warning when CONFIG_PCI=n")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>  drivers/crypto/inside-secure/safexcel.c | 49 ++++++-------------------
>  include/linux/pci.h                     |  1 +
>  2 files changed, 13 insertions(+), 37 deletions(-)
> ... 

> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index f9088c89a534..1a6cf19eac2d 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1686,6 +1686,7 @@ static inline struct pci_dev *pci_get_class(unsigned int class,
>  static inline void pci_set_master(struct pci_dev *dev) { }
>  static inline int pci_enable_device(struct pci_dev *dev) { return -EIO; }
>  static inline void pci_disable_device(struct pci_dev *dev) { }
> +static inline int pcim_enable_device(struct pci_dev *pdev) { return -EIO; }

I would have used "dev" here to match surrounding stubs, but either
way:

Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>	# pci.h

>  static inline int pci_assign_resource(struct pci_dev *dev, int i)
>  { return -EBUSY; }
>  static inline int __pci_register_driver(struct pci_driver *drv,
> -- 
> 2.20.0
>