[PATCH] ata: intf_platform_ide: add OF bindings

[Peter Mamonov]

Hi, Lucas!

On Thu, 03 Sep 2015 17:46:32 +0200
Lucas Stach <l.stach at pengutronix.de> wrote:

> Hi Peter.
> 
> Sorry, but this patch is wrong. You can't just make up completely
> ad-hoc DT bindings. You are pushing platformdata 1:1 into the DT,
> which is not how the conversion to DT should be done.

Could you clarify your point? My current understanding is that drivers
instantiation from a platform code and from a DT are equal approaches,
which should mirror each other.

> 
> There is also no pre-existing binding for "ata-generic" in the Linux
> kernel which would define any of those properties.
> 
> Most likely your IDE controller is inside some SoC specific block,
> with a specific compatible, which may also handle clocks and other
> required stuff and that one should instantiate the IDE driver if
> needed.

I've got your point. However, drivers/ata/pata_of_platform.c from Linux
also lacks any clock/stuff initialization.

Regards,
Peter


> 
> Regards,
> Lucas
> 
> Am Donnerstag, den 03.09.2015, 16:38 +0300 schrieb Peter Mamonov:
> > Signed-off-by: Peter Mamonov <pmamonov at gmail.com>
> > ---
> >  drivers/ata/intf_platform_ide.c | 35
> > +++++++++++++++++++++++++++++++++-- 1 file changed, 33
> > insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/ata/intf_platform_ide.c
> > b/drivers/ata/intf_platform_ide.c index 0d392d8..f20e0e0 100644
> > --- a/drivers/ata/intf_platform_ide.c
> > +++ b/drivers/ata/intf_platform_ide.c
> > @@ -29,6 +29,7 @@
> >  #include <ata_drive.h>
> >  #include <platform_ide.h>
> >  #include <linux/err.h>
> > +#include <of.h>
> >  
> >  /**
> >   * Setup the register specific addresses for an ATA like divice
> > @@ -85,10 +86,31 @@ static int platform_ide_probe(struct device_d
> > *dev) void *reg_base, *alt_base = NULL;
> >  	struct resource *reg, *alt;
> >  	int mmio = 0;
> > +	struct device_node *dn = dev->device_node;
> > +	u32 tmp32;
> >  
> >  	if (pdata == NULL) {
> > -		dev_err(dev, "No platform data. Cannot
> > continue\n");
> > -		return -EINVAL;
> > +		/* try to get platform data from the device tree */
> > +		if (dn == NULL) {
> > +			dev_err(dev, "No platform data. Cannot
> > continue\n");
> > +			return -EINVAL;
> > +		}
> > +
> > +		pdata = xzalloc(sizeof(struct ide_port_info));
> > +
> > +		if (!pdata) {
> > +			dev_err(dev, "Platform data allocation
> > failed\n");
> > +			return -ENOMEM;
> > +		}
> > +		device_add_data(dev, pdata, sizeof(struct
> > ide_port_info)); +
> > +		if (of_property_read_bool(dn, "dataif-be"))
> > +			pdata->dataif_be = 1;
> > +
> > +		if (of_property_read_u32(dn, "reg-shift", &tmp32)
> > == 0)
> > +			pdata->ioport_shift = (unsigned)tmp32;
> > +
> > +		dev->platform_data = pdata;
> >  	}
> >  
> >  	reg_base = dev_request_mem_region(dev, 0);
> > @@ -136,9 +158,18 @@ static int platform_ide_probe(struct device_d
> > *dev) return rc;
> >  }
> >  
> > +static __maybe_unused struct of_device_id platform_ide_dt_ids[] = {
> > +	{
> > +		.compatible = "ata-generic",
> > +	}, {
> > +		/* sentinel */
> > +	}
> > +};
> > +
> >  static struct driver_d platform_ide_driver = {
> >  	.name   = "ide_intf",
> >  	.probe  = platform_ide_probe,
> > +	.of_compatible = DRV_OF_COMPAT(platform_ide_dt_ids),
> >  };
> >  device_platform_driver(platform_ide_driver);
> >  
>