pinctrl: ocelot: add ability to be used in a non-mmio configuration

There are a few Ocelot chips that contain pinctrl logic, but can be
controlled externally. Specifically the VSC7511, 7512, 7513 and 7514. In
the externally controlled configurations these registers are not
memory-mapped.

Add support for these non-memory-mapped configurations.
Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20220905162132.2943088-4-colin.foster@in-advantage.com

drivers/pinctrl/pinctrl-ocelot.c

@@ -10,6 +10,7 @@
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/mfd/ocelot.h>
 #include <linux/of_device.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
@@ -1975,7 +1976,6 @@ static int ocelot_pinctrl_probe(struct platform_device *pdev)
 	struct ocelot_pinctrl *info;
 	struct reset_control *reset;
 	struct regmap *pincfg;
-	void __iomem *base;
 	int ret;
 	struct regmap_config regmap_config = {
 		.reg_bits = 32,
@@ -2004,20 +2004,14 @@ static int ocelot_pinctrl_probe(struct platform_device *pdev)
 				     "Failed to get reset\n");
 	reset_control_reset(reset);
 
-	base = devm_ioremap_resource(dev,
-			platform_get_resource(pdev, IORESOURCE_MEM, 0));
-	if (IS_ERR(base))
-		return PTR_ERR(base);
-
 	info->stride = 1 + (info->desc->npins - 1) / 32;
 
 	regmap_config.max_register = OCELOT_GPIO_SD_MAP * info->stride + 15 * 4;
 
-	info->map = devm_regmap_init_mmio(dev, base, &regmap_config);
-	if (IS_ERR(info->map)) {
-		dev_err(dev, "Failed to create regmap\n");
-		return PTR_ERR(info->map);
-	}
+	info->map = ocelot_regmap_from_resource(pdev, 0, &regmap_config);
+	if (IS_ERR(info->map))
+		return dev_err_probe(dev, PTR_ERR(info->map),
+				     "Failed to create regmap\n");
 	dev_set_drvdata(dev, info->map);
 	info->dev = dev;