Re: [PATCH v2] pata-generic/of: Make probing via device tree non-powerpc-specific

[Rob Herring <robherring2@gmail.com>]

Dave,

On 09/16/2011 11:22 AM, Dave Martin wrote:
> This patch enables device-tree-based probing of the pata-generic
> platform driver across all architectures:
> 
>   * make the pata_of_generic module depend on OF instead of PPC_OF;
>   * supply some missing inclues;
>   * replace endianness-sensitive raw access to device tree data
>     with of_property_read_u32() calls.
> 
> Signed-off-by: Dave Martin <dave.martin@linaro.org>
> ---
> v2: correct sense of the check of_property_read_u32(dn, "pio-mode",
> &pio_mode).  Somehow I posted an old version of this patch, depite
> having already fixed this...
> 
> Tested on ARM Versatile Express, with my soon-to-be-posted device
> tree support patches.
> 
> I'm not in a position to build/test this for powerpc easily --
> if anyone is able to do that, it would be appreciated.
> 
Building just requires getting Codesourcery PPC toolchain...

You also have to be aware that you are enabling this for all OF-enabled
arches which could break with an allyesconfig. So really you need sparc,
x86, mips, and microblaze, but a subset is probably sufficient.

> Grant, does this require similar cleanup to the isp1760 USB hcd driver?
> 
Yes. It really should be merged with pata_platform.c. If you're willing
to combine them, I'll do ppc and sparc builds as I already have those on
my system.

Rob

>  drivers/ata/Kconfig            |    2 +-
>  drivers/ata/pata_of_platform.c |   16 +++++++---------
>  2 files changed, 8 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index 5987e0b..c6ef9d0 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -820,7 +820,7 @@ config PATA_PLATFORM
>  
>  config PATA_OF_PLATFORM
>  	tristate "OpenFirmware platform device PATA support"
> -	depends on PATA_PLATFORM && PPC_OF
> +	depends on PATA_PLATFORM && OF
>  	help
>  	  This option enables support for generic directly connected ATA
>  	  devices commonly found on embedded systems with OpenFirmware
> diff --git a/drivers/ata/pata_of_platform.c b/drivers/ata/pata_of_platform.c
> index f305400..e6e9aa9 100644
> --- a/drivers/ata/pata_of_platform.c
> +++ b/drivers/ata/pata_of_platform.c
> @@ -11,6 +11,9 @@
>  
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
>  #include <linux/of_platform.h>
>  #include <linux/ata_platform.h>
>  
> @@ -21,10 +24,9 @@ static int __devinit pata_of_platform_probe(struct platform_device *ofdev)
>  	struct resource io_res;
>  	struct resource ctl_res;
>  	struct resource irq_res;
> -	unsigned int reg_shift = 0;
> -	int pio_mode = 0;
> +	u32 reg_shift = 0;
> +	u32 pio_mode = 0;
>  	int pio_mask;
> -	const u32 *prop;
>  
>  	ret = of_address_to_resource(dn, 0, &io_res);
>  	if (ret) {
> @@ -55,13 +57,9 @@ static int __devinit pata_of_platform_probe(struct platform_device *ofdev)
>  	else
>  		irq_res.flags = 0;
>  
> -	prop = of_get_property(dn, "reg-shift", NULL);
> -	if (prop)
> -		reg_shift = *prop;
> +	of_property_read_u32(dn, "reg-shift", &reg_shift);
>  
> -	prop = of_get_property(dn, "pio-mode", NULL);
> -	if (prop) {
> -		pio_mode = *prop;
> +	if (!of_property_read_u32(dn, "pio-mode", &pio_mode)) {
>  		if (pio_mode > 6) {
>  			dev_err(&ofdev->dev, "invalid pio-mode\n");
>  			return -EINVAL;