From mboxrd@z Thu Jan  1 00:00:00 1970
From: arnd@arndb.de (Arnd Bergmann)
Date: Mon, 19 Oct 2015 15:25:08 +0200
Subject: [PATCH 2/4] vfio: platform: reset: calxedaxgmac: add reset
 function registration
In-Reply-To: <5624ED6A.5030408@linaro.org>
References: <1445184015-24414-1-git-send-email-eric.auger@linaro.org>
 <3829716.dW4OHEgDOa@wuerfel> <5624ED6A.5030408@linaro.org>
Message-ID: <4837895.vpC7yteyEu@wuerfel>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Monday 19 October 2015 15:17:30 Eric Auger wrote:
> Hi Arnd,
> On 10/19/2015 03:04 PM, Arnd Bergmann wrote:
> > On Sunday 18 October 2015 18:00:13 Eric Auger wrote:
> >> diff --git a/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c b/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
> >> index 619dc7d..4f76b17 100644
> >> --- a/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
> >> +++ b/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
> >> @@ -29,8 +29,7 @@
> >>  #define DRIVER_VERSION  "0.1"
> >>  #define DRIVER_AUTHOR   "Eric Auger <eric.auger@linaro.org>"
> >>  #define DRIVER_DESC     "Reset support for Calxeda xgmac vfio platform device"
> >> -
> >> -#define CALXEDAXGMAC_COMPAT "calxeda,hb-xgmac"
> >> +#define COMPAT		"calxeda,hb-xgmac"
> > 
> > Why the rename?
> This define was not used. Since the code is meant to be duplicated from
> one reset module to the other I thought it did not bring any have a
> specialized name

I'd say it would be clearer to remove the macro then, and pass the
string literal in the function call.

> >>  /* XGMAC Register definitions */
> >>  #define XGMAC_CONTROL           0x00000000      /* MAC Configuration */
> >> @@ -80,6 +79,43 @@ int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev)
> >>  }
> >>  EXPORT_SYMBOL_GPL(vfio_platform_calxedaxgmac_reset);
> >>  
> >> +static int __init vfio_platform_calxedaxgmac_init(void)
> >> +{
> >> +	int (*register_reset)(struct module *, char*,
> >> +				vfio_platform_reset_fn_t);
> >> +	int ret;
> >> +
> >> +	register_reset = symbol_get(vfio_platform_register_reset);
> >> +	if (!register_reset)
> >> +		return -EINVAL;
> > 
> > I don't understand what you do the symbol_get() here for.
> > Why not just call that function directly
> the function is implemented in a separate module. This is just to make
> sure the vfio-platform module is loaded, in case the end-user attempts
> to load the reset module without having this latter loaded.

The module loader does all this for you.

	Arnd