Re: [PATCH] i2c: tegra: Add CONFIG_OF guards for device tree bits

[Sam Ravnborg <sam-uyr5N9Q2VtJg9hUCZPvPmw@public.gmane.org>]

On Fri, Aug 05, 2011 at 03:05:21PM +0800, Axel Lin wrote:
> The device tree bits need to be protected by CONFIG_OF guards.
> This patch fixes below build error with "make tegra_defconfig;make".
> 
>   CC      drivers/i2c/busses/i2c-tegra.o
> drivers/i2c/busses/i2c-tegra.c: In function 'tegra_i2c_probe':
> drivers/i2c/busses/i2c-tegra.c:615: error: implicit declaration of function 'of_get_property'
> drivers/i2c/busses/i2c-tegra.c:616: warning: assignment makes pointer from integer without a cast
> make[3]: *** [drivers/i2c/busses/i2c-tegra.o] Error 1
> make[2]: *** [drivers/i2c/busses] Error 2
> make[1]: *** [drivers/i2c] Error 2
> make: *** [drivers] Error 2
> 
> Signed-off-by: Axel Lin <axel.lin-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> ---
>  drivers/i2c/busses/i2c-tegra.c |    5 ++++-
>  1 files changed, 4 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> index 0c6e840..1bfe85e 100644
> --- a/drivers/i2c/busses/i2c-tegra.c
> +++ b/drivers/i2c/busses/i2c-tegra.c
> @@ -548,7 +548,6 @@ static int tegra_i2c_probe(struct platform_device *pdev)
>  	struct resource *iomem;
>  	struct clk *clk;
>  	struct clk *i2c_clk;
> -	const unsigned int *prop;
>  	void *base;
>  	int irq;
>  	int ret = 0;
> @@ -611,11 +610,15 @@ static int tegra_i2c_probe(struct platform_device *pdev)
>  	if (pdata) {
>  		i2c_dev->bus_clk_rate = pdata->bus_clk_rate;
>  
> +#ifdef CONFIG_OF
>  	} else if (i2c_dev->dev->of_node) {    /* if there is a device tree node ... */
> +		const unsigned int *prop;
> +
>  		prop = of_get_property(i2c_dev->dev->of_node,
>  				"clock-frequency", NULL);
>  		if (prop)
>  			i2c_dev->bus_clk_rate = be32_to_cpup(prop);
> +#endif
>  	}
>  
>  	if (pdev->id == 3)

It would be better to add a dummy implementation of of_get_property() in of.h.
Thus we do not need the ifdeffery and all users benefits from this.

	Sam