mtd: maps: gpio-addr-flash: fix warnings and make more portable

As reported on lkml, building this module for HIMEM systems spews warnings
about mismatch in pointer types.  Further, we need to use ioremap() in order
to properly access the flash memory on most systems rather than just doing
it directly.
Reported-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/maps/gpio-addr-flash.c

@@ -208,10 +208,14 @@ static int __devinit gpio_flash_probe(struct platform_device *pdev)
 	if (!state)
 		return -ENOMEM;
 
+	/*
+	 * We cast start/end to known types in the boards file, so cast
+	 * away their pointer types here to the known types (gpios->xxx).
+	 */
 	state->gpio_count     = gpios->end;
-	state->gpio_addrs     = (void *)gpios->start;
+	state->gpio_addrs     = (void *)(unsigned long)gpios->start;
 	state->gpio_values    = (void *)(state + 1);
-	state->win_size       = memory->end - memory->start + 1;
+	state->win_size       = resource_size(memory);
 	memset(state->gpio_values, 0xff, arr_size);
 
 	state->map.name       = DRIVER_NAME;
@@ -221,7 +225,7 @@ static int __devinit gpio_flash_probe(struct platform_device *pdev)
 	state->map.copy_to    = gf_copy_to;
 	state->map.bankwidth  = pdata->width;
 	state->map.size       = state->win_size * (1 << state->gpio_count);
-	state->map.virt       = (void __iomem *)memory->start;
+	state->map.virt       = ioremap_nocache(memory->start, state->map.size);
 	state->map.phys       = NO_XIP;
 	state->map.map_priv_1 = (unsigned long)state;