Re: [PATCH] of: provide of_n_{addr,size}_cells wrappers for !CONFIG_OF

From: Frank Rowand <frowand.list@gmail.com>
To: Arnd Bergmann <arnd@arndb.de>, Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org,
	Grant Likely <grant.likely@linaro.org>,
	Lucas Stach <l.stach@pengutronix.de>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Magnus Damm <damm@opensource.se>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Ben Dooks <ben.dooks@codethink.co.uk>,
	linux-pci@vger.kernel.org, linux-sh@vger.kernel.org,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	Sudeep Holla <sudeep.holla@arm.com>,
	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
	Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
	Alan Tull <atull@opensource.altera.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Richard Fitzgerald <rf@opensource.wolfsonmicro.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] of: provide of_n_{addr,size}_cells wrappers for !CONFIG_OF
Date: Fri, 21 Jul 2017 21:04:51 +0000	[thread overview]
Message-ID: <59726C73.6000000@gmail.com> (raw)
In-Reply-To: <20170721202012.3360244-1-arnd@arndb.de>

On 07/21/17 13:19, Arnd Bergmann wrote:
> The pci-rcar driver is enabled for compile tests, and this has
> now shown that the driver cannot build without CONFIG_OF,
> following the inclusion of f8f2fe7355fb "PCI: rcar: Use new OF
> interrupt mapping when possible":
> 
> ../drivers/pci/host/pcie-rcar.c: In function 'pci_dma_range_parser_init':
> ../drivers/pci/host/pcie-rcar.c:856:2: error: implicit declaration of function 'of_n_addr_cells' [-Werror=implicit-function-declaration]
>   parser->pna = of_n_addr_cells(node);
>   ^
> As pointed out by Ben Dooks and Geert Uytterhoeven, this is actually
> supposed to build fine, which we can achieve if we make the
> declaration of of_irq_parse_and_map_pci conditional on CONFIG_OF
> and provide an empty inline function otherwise, as we do for
> a lot of other of interfaces.
> 
> This lets us build the rcar_pci driver again without CONFIG_OF
> for build testing. All platforms using this driver select OF,
> so this doesn't change anything for the users.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Cc: devicetree@vger.kernel.org
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Grant Likely <grant.likely@linaro.org>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Magnus Damm <damm@opensource.se>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Ben Dooks <ben.dooks@codethink.co.uk>
> Cc: linux-pci@vger.kernel.org
> Cc: linux-sh@vger.kernel.org
> 
> ---
> I originally sent the patch in 2014 when things initially broke
> and then forgot about while it was applied in my randconfig patch
> stack. I sent it again in 2016 without replay.
> 
> It's still broken and I think this is the correct fix.
> ---
>  include/linux/of.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/include/linux/of.h b/include/linux/of.h
> index 4a8a70916237..1efdbe53136c 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -735,6 +735,9 @@ static inline struct device_node *of_get_cpu_node(int cpu,
>  	return NULL;
>  }
>  
> +static inline int of_n_addr_cells(struct device_node *np) { return 0; }
> +static inline int of_n_size_cells(struct device_node *np) { return 0; }
> +
>  static inline int of_property_read_u64(const struct device_node *np,
>  				       const char *propname, u64 *out_value)
>  {
> 

Reviewed-by: Frank Rowand <frank.rowand@sony.com>